IPCC AR6 Summary for Policymakers

154 views
Skip to first unread message

chris.vivian2

unread,
Aug 9, 2021, 5:48:38 AM8/9/21
to Carbon Dioxide Removal
In the IPCC AR6 Summary for Policymakers published today, see sections D.1.4 to D.1.6 on page 40 where it mentions CDR - https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf

Chris

Robert Cormia

unread,
Aug 9, 2021, 2:32:20 PM8/9/21
to chris.vivian2, Carbon Dioxide Removal
It took decades to get the public's attention about the clear and present danger of climate change, through extreme weather events, historic fires, and sea level rise. CDR is entering the dialog, slowly, it needs to accelerate. Newscasters could add a simple soundbite "net zero emissions and CO2 removal" as strategies, not just "clean energy and electric cars" How do we gain the public's awareness, much less attention, that putting a speed brake on emissions requires CDR, and restoring energy balance (addressing energy imbalance) is our best potential/feasible solution?  

-rdc

On Mon, Aug 9, 2021 at 2:48 AM 'chris.vivian2' via Carbon Dioxide Removal <CarbonDiox...@googlegroups.com> wrote:
In the IPCC AR6 Summary for Policymakers published today, see sections D.1.4 to D.1.6 on page 40 where it mentions CDR - https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf

Chris

--
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email to CarbonDioxideRem...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/d2ad5678-cf60-4af2-8968-3233344509f5n%40googlegroups.com.

Shannon A. Fiume

unread,
Aug 9, 2021, 3:29:41 PM8/9/21
to CarbonDiox...@googlegroups.com

Hi Robert & all,

It's pretty risky at this point to not mention it along side renewables.

Most people equate CDR with CCS thanks to thought pieces in the Conversation and other major intellectual press.

The modeling does show that we need to hit net-zero sharply then continue deeply negative. We'll also need massive outlay of power for nonFF based CDR.

So anyway to slice it, we need Manhattan levels, not just Apollo levels of effort on renewables (THIS DECADE) to have hope of getting CDR in place to remove more to lower emissions (NEXT DECADE).

github.com/hsbay/CDRMEx (look for the workbook in the readme.)

Regards,

~~sa

Robert Tulip

unread,
Aug 11, 2021, 7:16:45 AM8/11/21
to Carbon Dioxide Removal, geoengineering

I thought it was pretty bad that the IPCC report states as its headline B.1 finding that "Global warming of 1.5°C and 2°C will be exceeded during the 21st century unless deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades."

It should rather state "Global warming of 1.5°C and 2°C will be exceeded during the 21st century even if deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades." (my bold)

As the NOAA AGGI report states, CO2 equivalents are now above 500 ppm. Emission reduction, technically defined, only reduces the future addition of GHGs to the system, and does nothing to remove the committed warming from past emissions. Leading scientists (eg Eelco Rohling) think past emissions already commit the planet to 2°C.

Even a major program of carbon conversion, transforming CO2 into useful commodities such as soil and fabric, would do nothing to stop the escalation of extreme weather this decade. Carbon removal is too small and slow, despite having orders of magnitude greater potential cooling impact than decarbonisation of the world economy.

My view is the only immediate solution is to brighten the planet. Albedo enhancement should start by pumping sea water onto the Arctic sea ice in winter to freeze and reduce the summer melt using wind energy (diagram attached). Marine cloud brightening is the next best option, followed by areas that need considerably more impact research such as stratospheric aerosol injection and iron salt aerosol.

It is a disgrace that the IPCC seems to have entirely written off this whole area of response, with no scientific reasoning as to why.

 

I understand that people find climate intervention for planetary restoration a rather mind-boggling idea and would prefer it were not needed. The problem is that extreme weather is steadily getting worse, and cutting emissions through the energy transition can do nothing to stop it. The overall issue is to define a scientific response to climate policy. That means relying on evidence to define the most safe and effective methods to support ongoing climate stability. Sadly AR6 squibbed that challenge.

Much of the public policy relies on other factors as well as science. Notably this is about public perceptions rather than empirical assessment. But that means the climate activist community will no longer be able to use the mantra "the science says" to oppose geoengineering, as Michael Mann and Bill McKibben and others now do.

I think the factors that could change public opinion quite quickly include the idea that immediate action to refreeze the Arctic is essential to maintain stability of main ocean currents. I was very perturbed to see the 
report last week on the slowing down of the AMOC Atlantic Meridional Overturning Circulation and Gulf Stream collapse, with potential disasters for the world economy and ecology.

The linked press report suggested that decarbonising the economy is "the only thing to do" to prevent the AMOC from stopping. That is an absurdly unscientific opinion. It just fails to see that such natural processes require action at orders of magnitude bigger scale than the marginal effect of slowing down how much carbon we add to the air.

If steps were taken to fully refreeze the Arctic Ocean, perhaps with the quid pro quo of including 
transpolar shipping canals through the ice, the scale would be big enough to stop the dangerous looming tipping points of accelerating feedback warming. Alongside AMOC, big problems such as polar methane release, wandering of the jet stream and melting of the Greenland Ice Sheet are also well beyond what decarbonisation can prevent.

I really don't see any downside to such a freezing proposal, which should be an Apollo-type world peace project led by the G20. The climate activist community sees it as enabling a slower transition to renewables, but surely buying time in this way is entirely a good thing if it means we actually stabilise the climate?

 

Robert Tulip

Freezing Arctic Sea Ice with Wind Pumps.png

Nucleation Capital

unread,
Aug 11, 2021, 3:38:31 PM8/11/21
to Robert Tulip, Carbon Dioxide Removal, geoengineering, val...@nucleationcapital.com
Robert,

Just so you are aware, the report released by the IPCC this week is just the IPCC Working Group 1 portion of a much larger three-part report, looking at the Physical bases. The official description is:  "The Working Group I contribution to the Sixth Assessment Report addresses the most up-to-date physical understanding of the climate system and climate change, bringing together the latest advances in climate science, and combining multiple lines of evidence from paleoclimate, observations, process understanding, and global and regional climate simulations."  Even the Summary for Policymakers (SPM) document does not speak to climate policy at all, just a summary of the physical findings. I believe the Sixth Assessment Synthesis Report, due out in September 2022, will have the policy discussion that you are looking for.  See here for the IPCC's full description of the sections and contents of the Sixth Assessment (i.e. the 6th full assessment in 30 years).

Valerie

Valerie Gardner, Managing Partner

Sarnoff, Joshua

unread,
Aug 11, 2021, 8:07:37 PM8/11/21
to Jonathan...@uts.edu.au, geoengineering, Carbon Dioxide Removal

Our fellows’ antivaxx and antimask proclivities are doing that for us already.

 

Josh

 

From: <geoengi...@googlegroups.com> on behalf of Jonathan Marshall <Jonathan...@uts.edu.au>


Reply-To: "jonathan...@uts.edu.au" <Jonathan...@uts.edu.au>
Date: Wednesday, August 11, 2021 at 8:03 PM
To: geoengineering <geoengi...@googlegroups.com>
Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>

Subject: [EXT] Re: [geo] RE: IPCC AR6 Summary for Policymakers

 


Yes it is true that there are levels of population which are unsustainable, but the problem with emissions is the distribution of emissions via population.

It would seem obvious that if we were to focus on lowering populations we should lower those populations which have the greatest ecological and climate impact per head. That is we should lower the populations of the US and Australia etc, first.

We should probably volunteer for elimination.....



________________________________________
From: geoengi...@googlegroups.com <geoengi...@googlegroups.com> on behalf of SALTER Stephen <S.Sa...@ed.ac.uk>
Sent: Thursday, 12 August 2021 7:09 AM
To: cushn...@gmail.com; rtuli...@yahoo.com.au
Cc: Carbon Dioxide Removal; geoengineering
Subject: RE: [geo] RE: IPCC AR6 Summary for Policymakers

Hi All

Behind every root cause is another root cause. The root cause of greenhouse gases is excessive human population. An effective solution to that is uncomfortably topical but would not be well received.

Stephen

From: geoengi...@googlegroups.com <geoengi...@googlegroups.com> On Behalf Of Cush Ngonzo Luwesi
Sent: Wednesday, August 11, 2021 8:30 PM
To: rtuli...@yahoo.com.au
Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>
Subject: Re: [geo] RE: IPCC AR6 Summary for Policymakers

This email was sent to you by someone outside the University.
You should only click on links or attachments if you are certain that the email is genuine and the content is safe.
Dear Robert
I enjoyed pretty much reading your critique on the IPCC AR6 report and the AMOC report. I notices that thèse reports put an emphasis on mitigation and negative emissions as the way to slowing down ice melting and Climate variability. Yet, these arguments seem to be "unscientific" to you because of your take on Solar geoengineering. Yet, many observées think that brightening the marine clouds and spraying aérosols do not solve the very cause of Climate change, which is GHGe. Yet, to D. Hume's point of view, a "scientific" control is the one that Solves causality, meaning a solution that controls or stabilises the causes. What is your take on this? To what science do you refer to in your commenté? Who is fooling who?
Thanks in advance for your feedback.
Regards
Cush

Le mer. 11 août 2021 à 12:16, 'Robert Tulip' via geoengineering <geoengi...@googlegroups.com<mailto:geoengi...@googlegroups.com>> a écrit :
I thought it was pretty bad that the IPCC report<https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf> states as its headline B.1 finding that "Global warming of 1.5°C and 2°C will be exceeded during the 21st century unless deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades."



It should rather state "Global warming of 1.5°C and 2°C will be exceeded during the 21st century even if deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades." (my bold)

As the NOAA AGGI report<https://gml.noaa.gov/aggi/> states, CO2 equivalents are now above 500 ppm. Emission reduction, technically defined, only reduces the future addition of GHGs to the system, and does nothing to remove the committed warming from past emissions. Leading scientists (eg Eelco Rohling) think past emissions already commit the planet to 2°C.



Even a major program of carbon conversion, transforming CO2 into useful commodities such as soil and fabric, would do nothing to stop the escalation of extreme weather this decade. Carbon removal is too small and slow, despite having orders of magnitude greater potential cooling impact than decarbonisation of the world economy.

My view is the only immediate solution is to brighten the planet. Albedo enhancement should start by pumping sea water onto the Arctic sea ice in winter to freeze and reduce the summer melt using wind energy (diagram attached). Marine cloud brightening is the next best option, followed by areas that need considerably more impact research such as stratospheric aerosol injection and iron salt aerosol.

It is a disgrace that the IPCC seems to have entirely written off this whole area of response, with no scientific reasoning as to why.

I understand that people find climate intervention for planetary restoration a rather mind-boggling idea and would prefer it were not needed. The problem is that extreme weather is steadily getting worse, and cutting emissions through the energy transition can do nothing to stop it. The overall issue is to define a scientific response to climate policy. That means relying on evidence to define the most safe and effective methods to support ongoing climate stability. Sadly AR6 squibbed that challenge.

Much of the public policy relies on other factors as well as science. Notably this is about public perceptions rather than empirical assessment. But that means the climate activist community will no longer be able to use the mantra "the science says" to oppose geoengineering, as Michael Mann and Bill McKibben and others now do.

I think the factors that could change public opinion quite quickly include the idea that immediate action to refreeze the Arctic is essential to maintain stability of main ocean currents. I was very perturbed to see the report last week on the slowing down of the AMOC Atlantic Meridional Overturning Circulation<https://www.theguardian.com/environment/2021/aug/05/climate-crisis-scientists-spot-warning-signs-of-gulf-stream-collapse> and Gulf Stream collapse, with potential disasters for the world economy and ecology.



The linked press report suggested that decarbonising the economy is "the only thing to do" to prevent the AMOC from stopping. That is an absurdly unscientific opinion. It just fails to see that such natural processes require action at orders of magnitude bigger scale than the marginal effect of slowing down how much carbon we add to the air.

If steps were taken to fully refreeze the Arctic Ocean, perhaps with the quid pro quo of including transpolar shipping canals <https://en.wikipedia.org/wiki/Transpolar_Sea_Route> through the ice, the scale would be big enough to stop the dangerous looming tipping points of accelerating feedback warming. Alongside AMOC, big problems such as polar methane release, wandering of the jet stream and melting of the Greenland Ice Sheet are also well beyond what decarbonisation can prevent.



I really don't see any downside to such a freezing proposal, which should be an Apollo-type world peace project led by the G20. The climate activist community sees it as enabling a slower transition to renewables, but surely buying time in this way is entirely a good thing if it means we actually stabilise the climate?

Robert Tulip

From: carbondiox...@googlegroups.com<mailto:carbondiox...@googlegroups.com> <carbondiox...@googlegroups.com<mailto:carbondiox...@googlegroups.com>> On Behalf Of Robert Cormia
Sent: Tuesday, 10 August 2021 4:32 AM
To: chris.vivian2 <Chris....@btinternet.com<mailto:Chris....@btinternet.com>>
Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com<mailto:CarbonDiox...@googlegroups.com>>
Subject: Re: [CDR] IPCC AR6 Summary for Policymakers

It took decades to get the public's attention about the clear and present danger of climate change, through extreme weather events, historic fires, and sea level rise. CDR is entering the dialog, slowly, it needs to accelerate. Newscasters could add a simple soundbite "net zero emissions and CO2 removal" as strategies, not just "clean energy and electric cars" How do we gain the public's awareness, much less attention, that putting a speed brake on emissions requires CDR, and restoring energy balance (addressing energy imbalance) is our best potential/feasible solution?

-rdc

On Mon, Aug 9, 2021 at 2:48 AM 'chris.vivian2' via Carbon Dioxide Removal <CarbonDiox...@googlegroups.com<mailto:CarbonDiox...@googlegroups.com>> wrote:
In the IPCC AR6 Summary for Policymakers published today, see sections D.1.4 to D.1.6 on page 40 where it mentions CDR - https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf<https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf>>.

Chris
--
You
received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email to CarbonDioxideRem...@googlegroups.com<mailto:CarbonDioxideRem...@googlegroups.com>.
To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/d2ad5678-cf60-4af2-8968-3233344509f5n%40googlegroups.com<https://groups.google.com/d/msgid/CarbonDioxideRemoval/d2ad5678-cf60-4af2-8968-3233344509f5n%40googlegroups.com?utm_medium=email&utm_source=footer>>.
--
You
received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email to CarbonDioxideRem...@googlegroups.com<mailto:CarbonDioxideRem...@googlegroups.com>.
To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/CA%2B-rYQEG6iTG9qVC3GD-H5n6JdCBP%3Dwe3T24P-%2BUz6BR3E%2BhNg%40mail.gmail.com<https://groups.google.com/d/msgid/CarbonDioxideRemoval/CA%2B-rYQEG6iTG9qVC3GD-H5n6JdCBP%3Dwe3T24P-%2BUz6BR3E%2BhNg%40mail.gmail.com?utm_medium=email&utm_source=footer>>.
--
You
received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com<mailto:geoengineerin...@googlegroups.com>.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/012c01d78ea2%2457f06f20%2407d14d60%24%40yahoo.com.au<https://groups.google.com/d/msgid/geoengineering/012c01d78ea2%2457f06f20%2407d14d60%24%40yahoo.com.au?utm_medium=email&utm_source=footer>>.
--
You
received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com<mailto:geoengineerin...@googlegroups.com>.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAKo_7aqgYHE8Jo3yYZ74XE-_%3DnZMbdBotfnTwr2hWSep97kJQg%40mail.gmail.com<https://groups.google.com/d/msgid/geoengineering/CAKo_7aqgYHE8Jo3yYZ74XE-_%3DnZMbdBotfnTwr2hWSep97kJQg%40mail.gmail.com?utm_medium=email&utm_source=footer>>.
The
University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336.

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com<mailto:geoengineerin...@googlegroups.com>.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/AS8PR05MB79607CFA286D6C9A5196E2C2A7F89%40AS8PR05MB7960.eurprd05.prod.outlook.com<https://groups.google.com/d/msgid/geoengineering/AS8PR05MB79607CFA286D6C9A5196E2C2A7F89%40AS8PR05MB7960.eurprd05.prod.outlook.com?utm_medium=email&utm_source=footer>>.

UTS CRICOS Provider Code: 00099F DISCLAIMER: This email message and any accompanying attachments may contain confidential information. If you are not the intended recipient, do not read, use, disseminate, distribute or copy this message or attachments. If you have received this message in error, please notify the sender immediately and delete this message. Any views expressed in this message are those of the individual sender, except where the sender expressly, and with authority, states them to be the views of the University of Technology Sydney. Before opening any attachments, please check them for viruses and defects. Think. Green. Do. Please consider the environment before printing this email.

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/SYCPR01MB53286E5FA4C7D28DB644865DDBF89%40SYCPR01MB5328.ausprd01.prod.outlook.com.

Michael MacCracken

unread,
Aug 11, 2021, 9:22:52 PM8/11/21
to s.sa...@ed.ac.uk, cushn...@gmail.com, rtuli...@yahoo.com.au, Carbon Dioxide Removal, geoengineering

Actually, on population, back in 2000, the one billion or so in the developed world had us (and still do have us) on a path that would cause disastrous change, just a few decades later. To stop climate this billion was going to have to change its ways.

At the time, the five billion or so in the developed world were a pretty small share of the problem and if they had gone to zero emissions, as noted, the billion would have to have changed--and be doing so now.

Of course, now the six billion in developing world are increasing their emissions, still at a per capita level lower than in the developed world, and even if developed world went to zero emissions, the path they are on would take them to disastrous climate change.

Both developed and developing have to change their ways and choices--we really can't have any emissions and need to get to negative emissions, so it is the choices that all of us have and are making that is the really key issue, and this is true no matter what the population is assuming it stays above a billion or so.

So, not really appropriate to be thinking population is the key issue--it is our choices that need to change, for all of us, no matter the number. Yes, with fewer people it might be a bit easier for the world to change and stretch out the time maybe a decade, but given we are already a couple of decades too late, the focus has to be on the choices and changing them--rapidly.

Mike MacCracken


On 8/11/21 5:09 PM, SALTER Stephen wrote:

Hi All

 

Behind every root cause is another root cause. The root cause of greenhouse gases is excessive human population.  An effective solution to that is uncomfortably topical but would not be well received.

 

Stephen

 

From: geoengi...@googlegroups.com <geoengi...@googlegroups.com> On Behalf Of Cush Ngonzo Luwesi
Sent: Wednesday, August 11, 2021 8:30 PM
To: rtuli...@yahoo.com.au
Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>
Subject: Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

This email was sent to you by someone outside the University.

You should only click on links or attachments if you are certain that the email is genuine and the content is safe.

Dear Robert

I enjoyed pretty much reading your critique on the IPCC AR6 report and the AMOC report. I notices that thèse reports put an emphasis on mitigation and negative emissions as the way to slowing down ice melting and Climate variability. Yet, these arguments seem to be "unscientific" to you because of your take on Solar geoengineering. Yet, many observées think that brightening the marine clouds and spraying aérosols do not solve the very cause of Climate change, which is GHGe. Yet, to D.  Hume's point of view, a "scientific" control is the one that Solves causality, meaning a solution that controls or stabilises the causes. What is your take on this? To what science do you refer to in your commenté? Who is fooling who?

Thanks in advance for your feedback.

Regards

Cush

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/012c01d78ea2%2457f06f20%2407d14d60%24%40yahoo.com.au.

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAKo_7aqgYHE8Jo3yYZ74XE-_%3DnZMbdBotfnTwr2hWSep97kJQg%40mail.gmail.com.

The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336. --
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/AS8PR05MB79607CFA286D6C9A5196E2C2A7F89%40AS8PR05MB7960.eurprd05.prod.outlook.com.

Robert Tulip

unread,
Aug 12, 2021, 4:58:10 AM8/12/21
to cushn...@gmail.com, Carbon Dioxide Removal, geoengineering

Hello Cush

 

As I mentioned, the issue is timeframes. 

 

You are correct that GHGs are the cause of climate change.  That does not mean removing GHGs, let alone just slowing the rate of increase as the AR6 summary implies, is the only possible response.

 

Reducing GHG levels and emissions will take a long time.  Meanwhile we face extreme weather, biodiversity collapse and the risk of various dangerous tipping points. We have a planetary duty to address these crises.

 

Increasing albedo could prevent many effects of warming.  Brightening the pole would do far more to protect the AMOC than GHG removal would.  Higher albedo would bring numerous beneficial flow on effects for planetary stability and security.  It is absurdly stupid that these benefits of a brighter planet are not factored into IPCC calculations on risk, illustrating the dominance of politics over science.

 

Cutting emissions will not protect AMOC on a timescale shorter than a century.  That is far too slow to be relevant to the looming security emergency of a great oceanic disruption.

 

The same issue applies for ice melt, methane release and other phase shifts now occurring.  We need to buy time to ramp up GHG removal by brightening the planet.

 

Regards, Robert

 

From: geoengi...@googlegroups.com <geoengi...@googlegroups.com> On Behalf Of Cush Ngonzo Luwesi
Sent: Thursday, 12 August 2021 5:30 AM
To: rtuli...@yahoo.com.au
Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>
Subject: Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

Dear Robert

I enjoyed pretty much reading your critique on the IPCC AR6 report and the AMOC report. I notices that thèse reports put an emphasis on mitigation and negative emissions as the way to slowing down ice melting and Climate variability. Yet, these arguments seem to be "unscientific" to you because of your take on Solar geoengineering. Yet, many observées think that brightening the marine clouds and spraying aérosols do not solve the very cause of Climate change, which is GHGe. Yet, to D.  Hume's point of view, a "scientific" control is the one that Solves causality, meaning a solution that controls or stabilises the causes. What is your take on this? To what science do you refer to in your commenté? Who is fooling who?

Thanks in advance for your feedback.

Regards

Cush

Le mer. 11 août 2021 à 12:16, 'Robert Tulip' via geoengineering <geoengi...@googlegroups.com> a écrit :

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/012c01d78ea2%2457f06f20%2407d14d60%24%40yahoo.com.au.

--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAKo_7aqgYHE8Jo3yYZ74XE-_%3DnZMbdBotfnTwr2hWSep97kJQg%40mail.gmail.com.

Robert Tulip

unread,
Aug 12, 2021, 5:44:34 AM8/12/21
to Nucleation Capital, Carbon Dioxide Removal, geoengineering, val...@nucleationcapital.com

Hello Valerie

 

You may not have understood my comments.  Sorry if I was not clear. 

 

You state “Even the Summary for Policymakers (SPM) document does not speak to climate policy at all.”   That is not true. Per my first comment, headline B.1 of the SPM implies that only emission reduction can prevent dangerous warming.  That is a climate policy assertion, ruling out the alternative view that preventing dangerous warming requires increased albedo.

 

The complete absence of discussion of albedo from the SPM gives rise to the concern that it will not be addressed in later IPCC reports unless there is significant policy change.

 

Robert

 

From: Nucleation Capital <nucleati...@gmail.com>
Sent: Thursday, 12 August 2021 5:38 AM
To: Robert Tulip <rtuli...@yahoo.com.au>
Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; val...@nucleationcapital.com
Subject: Re: [CDR] RE: IPCC AR6 Summary for Policymakers

 

Robert,

Just so you are aware, the report released by the IPCC this week is just the IPCC Working Group 1 portion of a much larger three-part report, looking at the Physical bases. The official description is:  "The Working Group I contribution to the Sixth Assessment Report addresses the most up-to-date physical understanding of the climate system and climate change, bringing together the latest advances in climate science, and combining multiple lines of evidence from paleoclimate, observations, process understanding, and global and regional climate simulations."  Even the Summary for Policymakers (SPM) document does not speak to climate policy at all, just a summary of the physical findings. I believe the Sixth Assessment Synthesis Report, due out in September 2022, will have the policy discussion that you are looking for.  See here for the IPCC's full description of the sections and contents of the Sixth Assessment (i.e. the 6th full assessment in 30 years).

Valerie


Valerie Gardner, Managing Partner

image001.png

Delton Chen

unread,
Aug 12, 2021, 5:47:19 AM8/12/21
to Robert Tulip, Carbon Dioxide Removal, geoengineering, chris.vivian2, val...@nucleationcapital.com, s.sa...@ed.ac.uk, cushn...@gmail.com
Dear Robert and others,

The theme of this email thread is existentially important, because it refers to a fundamental problem—which is that there are two major physical pathways for climate mitigation: (i) managing the anthropogenic carbon balance with conventional mitigation and carbon dioxide removal (CDR), and (ii) managing the Earth's albedo to reflect radiation back to space (solar radiation management, SRM). These two pathways could be implemented simultaneously as complements, assuming that the approproate technologies are tested and have acceptable downside risks and tradeoffs.

Geo-engineering the Earth's albedo may be necessary and advantageous—depending on how things play out—but there is a major barrier to strong investment in SRM, which is (obviously) that the mainstream political narratives are against SRM for at least one major reason: we do not currently have global "agency" or "capacity" to manage our greenhouse gas emissions (GHGs).
Subsequently, the promotion of SRM is seen as a political risk because it could give polluters the impression that they can continue to pollute (or not reduce their emissions extremely quickly).

What I described above is not new. It's just a quick summary of our predicament.

What I am proposing here is new. I have another interpretation of this situation, which is really quite different to any other interpretation that I have seen in the mainstream press, on social media, or in the scientific literature.

The alternative interpretation is that we are unable to manage our anthropogenic carbon balance because we do not currently have the appropriate policy toolkit for actually being effective at managing the anthropogenic carbon balance. In other words, it is quite possible that the root problem is not the political standoff on climate change—but rather it is the standard economic theory and the standard policy toolkit that are the root problem.

My interpretation (and you can read about it here  https://globalcarbonreward.org/carbon-currency/pricing-theory/ and see Footnote b especially) is that our civilisation is behaving as a complex adaptive system with specific emergent properties. These properties form a biophysical phase-space that describe the health or state of civilisation, in response to CO2 concentrations and avg. temperatures.

The biophysical phase-plane for civilisation is 2D when the earth's albedo is constant (i.e.  the anthropogenic carbon balance is managed in 2D). The 2D phase plane requires two primary controllers, namely carbon taxes (or similar) and carbon rewards—in order to manage the carbon balance. Given that we do not have the carbon reward on the table for discussion, or in play as an international policy, it would appear that we (i.e. humanity) will not be able to manage the anthropogenic carbon balance with any confidence.

If, however, the carbon reward were introduced, it is conceivable that we could gain control over the  anthropogenic carbon balance. If that were to happen in some meaningful way, then the cynical politics over SRM would begin to dissolve and could be replaced with a more objective and scientific understanding of SRM. This is because albedo management (i.e. with SRM) appears to form the 3rd dimension of the biophysical 3D phase space for civilisation's survivability, in relation to GHGs and avg. surface temperature.

The 3D phase space for civilisation needs to be scientifically reviewed and experimentally tested. To do that I will need to find a team of competent physcists (i.e. people who can communicate effectively and like to work in teams). The theory underpinning the 3D biophysical phase space is mostly complete, and it looks promising given that it appears to resolve so many diverse theoretical problems in economics and biology etc.— but it is currently only a hypothesis.

Please contact me if you know any good physcists.

Sincerely
Delton Chen Ph.D.



Kevin Lister

unread,
Aug 12, 2021, 8:01:52 AM8/12/21
to Robert Tulip, Carbon Dioxide Removal, geoengineering
To answer Robert's comments on not seeing a downside to his proposal, and in the immortal intellectual framework of a previous Secretary of Defence:

There are known knowns, these are:


  • If you are dropping wind turbines out of a plane, then best guess is that these would have a maximum power output of 2kW, or thereabouts.  If they successfully land and penetrate the ice and start pumping, and the water forms a volcano shaped dome, with an inclination angle of 0.1 deg, then it will take a approximately 161 days to grow a cone that is 3 meters high at the pump, and it will have a radius of 1.7km. It would then take about 107,000 of these to cover the ice sheet.  That's a lot and probably far more than all the planes of the US strategic deployment force can deliver at the beginning of winter.  Even if this is successful, a significant number will be released from the edge of the ice in summer, say 10%, so approximately 10,000 will float around in the ocean. 

Then there are known unknowns, these are:

  • You do not know the angle that the water will settle on the ice,
  • You do not know what shape the ice will form around the pump, it is likely to be a more complex and irregular doughnut shape. The mathematics behind this is extremely complicated, and after about a year's effort I managed only a partial solution before giving up. 
  • You do not know what effect the continual heat flow from the subsurface water being pumped onto the existing ice surface will have. In extremis, the pumps could cause the ice adjacent to them to melt so all they end up doing is pumping water into water. 
  • Even if there are solutions to all of these, there is the practical engineering matter of establishing the reliability of the pumps, especially when they are to operate in the Arctic winter which is both cold, dark and inaccessible. 

Then there are the unknown unknowns, these are:

  • With the heat flow into the Arctic from the lower latitudes, then getting reliable and consistent ice formation, even in the depths of winter, may no longer be possible. 
  • Ice formed on the surface of existing ice is of a totally different structure to ice naturally formed by freezing downwards from the existing ice. This new ice may have a structure more like glass and be of low albedo, so in the summer it could act as a miniature greenhouse on the existing ice, which is also being warmed from below, thus accelerating the loss of existing ice when it is needed the most.  This would be the worst case scenario. We prevent heat release in the winter and minimise albedo in the summer. 
  • It is now as big an issue to release heat from the planet as it is to stop more heat coming in. Given that the Arctic sea ice is now fatally doomed, an alternative is to accept this and smash up the remaining ice in the winter with icebreakers to allow the most rapid release of heat to space, at an estimated rate ~500W/m^2

This is not to say that we should not increase planetary albedo and find ways to release heat. We clearly must do it. I maintain that the safe temperature rise is less than 0.5degC above baseline, which we passed through in 1980.  But we should be under no illusions that this is going to be simple and absent of scientific and engineering risks.

Finally, and as you point out, carbon removal will be slow. The natural rate of removal is so slow as to not be measurable against CO2 emissions and the paleoclimate records that the AR6 is now taking more notice of indicates it will take about 250k years for CO2 to fall back to safe levels. So, as well as exploring all viable albedo and heat releasing mechanisms, we must immediately and simultaneously find ways to decarbonise. 

Kevin






You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/012c01d78ea2%2457f06f20%2407d14d60%24%40yahoo.com.au.

Bruce Melton -- Austin, Texas

unread,
Aug 12, 2021, 11:41:01 AM8/12/21
to CarbonDiox...@googlegroups.com

I want to recommend Richard Alley's, Two-mile Time Machine (2006) and Wally Broeker's, Fixing Climate 2009, for a simple concept about carrying capacity that relates to climate pollution. These are excellent reads by a couple of our foremost climate and Earth systems scientists that, though approaching classic status by climate change standards, delve deep into fundamentals not common in our climate culture.

The carrying capacity concept that relates to climate pollution comes from both of these authors, not written as a carrying capacity issue, but as a pollution issue that had definitive limits on the welfare and proliferation of our civilization.

One of the earliest carrying capacity issues on Earth was the trees for fuel conundrum. It was overcome as the trees ran out and we adopted peat and coal for fuel. Then as our population grew beyond the boundaries of its limitations from our trees as fuel culture, disease from human sewage began killing millions. Earth's population at the time was about 1 billion. When we learned the diseases were caused by microorganisms in human sewage in the 19th century, haphazardly dumped in ditches from chamber pots or leaking from shallow privies, we changed how we treated human sewage, but it took a while.

Engineers and scientists of the 19th century were scoffed at for generations because their new-fangled ideas about microorganisms and disease, and that we needed to collect our human sewage in pipes and dump it in the river. The momentum of ignorance can be deadly, but us engineers and scientists can create and implement new realities that change that momentum. So, we began to treat human sewage pollution differently, resulting in an increased carrying capacity from this single acute abuse of our biosphere.

Cheers,

B


Bruce Melton PE
Director, Climate Change Now Initiative, 501c3
President, Melton Engineering Services Austin
8103 Kirkham Drive
Austin, Texas 78736
(512)799-7998
ClimateDiscovery.org
MeltonEngineering.com
Face...@Bruce.Melton.395
Inst...@Bruce.C.Melton
The Band Climate Change
Twitter - BruceCMelton1


Clive Elsworth

unread,
Aug 12, 2021, 12:37:44 PM8/12/21
to Bruce Melton -- Austin, Texas, CarbonDiox...@googlegroups.com
Mike

>given we are already a couple of decades too late, the focus has to be on the choices and changing them--rapidly.

That's why I've been jumping up and down for years now about the Stable Salt Reactor - cheaper than gas (because it removes the main hazard of radioactive gases under very high pressures), power on-demand, near zero emissions, tiny physical footprint as well, essentially unlimited fuel supply, and now an 850C version coming in 2028, ideal for making cheap hydrogen.

The problem we have is the 'tragedy of the incumbents' - losers who are good at picking governments. e.g. the UK gov prefers to finance their friends' more expensive, less globally scalable alternative the HTGR, cooled by helium.

But all this is about reducing GHG emissions, one day. The imperative is to provide planetary cooling, and that needs to get much more firmly on the global political radar.

Clive

Dan Galpern

unread,
Aug 12, 2021, 2:54:43 PM8/12/21
to Robert Tulip, Nucleation Capital, Carbon Dioxide Removal, geoengineering, val...@nucleationcapital.com
Aug. 12, 2021

Robert et al,

You are right to highlight the delayed climate response to emissions reductions and negative emissions. 

The full AR 6 WG1 report discusses this in its draft §4.6.3.2 Climate Response to Mitigation by Carbon Dioxide Removal, wherein it rather clumsily observes that "there could be a substantial delay between the initiation of CDR and net CO2 emissions turning negative (van Vuuren et al., 2016), and the time to reach net negative CO2 emissions and the evolution of atmospheric CO2 and climate thereafter would depend on the combined pathways of anthropogenic CO2 emissions, CDR, and natural sinks."

Right after that, the full AR 6 WG1 report does contain a section, namely §4.6.3.3, on Climate Response to Solar Radiation Modification.

The authors there briefly discuss surface albedo enhancements, including "enhancing the albedo of the ocean surface," p. 4-89, and conclude that "the technology does not exist today to increase ocean albedo at large scale." They do denote the proposal to pump seawater on top of the ice surface, describing it as one among several proposed "local intervention methods" and citing to publications in 2017 through 2019. But they conclude that "these methods are subject to large uncertainty concerning their feasibility and effectiveness, and their effects would be largely localized." 4-90.

I don't know of other studies or reports affording more confidence in this method of SRM. Do you?

In any event, I also concur that the serious pursuit of substantial SRM must not in any way delay the critical business of eliminating new and legacy emissions since, as the WG1 report also strongly implies, 4-91, significant SRM makes sense only if accompanied with mitigation and CDR. Otherwise, when SRM is later phased out, large additional warming could not be avoided.

Dan

Daniel M. Galpern, General Counsel & Executive Director
Climate Protection and Restoration Initiative

Michael MacCracken

unread,
Aug 12, 2021, 5:08:34 PM8/12/21
to jha...@berkeley.edu, kevin.li...@gmail.com, Robert Tulip, Carbon Dioxide Removal, geoengineering

Hi John--I've heard arguments both ways on this (e.g., Susan Solomon et al. some years ago in Science; she worked with CO2e and I think used the CO2 decay times, and had a very long tail; I've heard, I think it was, Steve Pacala and Steve Hamburg make the same point you are--namely the fluxes would continue for a while and I think they suggest the CO2 concentration would get pulled down by about 50 ppm) and am wondering what the resolution is on this (I've yet to read the IPCC relevant chapter on this).

Basically, the question is the extent to which these fluxes are driven by the concentration gradient created by the current year's emissions versus by the gradients created by past emissions. For the atmosphere to the wind-mixed upper ocean, the lag time I think is pretty short (1-2 years), but then from the upper ocean to deep ocean may well be based mainly on gradient created by past emissions, so it may persist for a while, but that flux is pretty small, so emissions would need to get below the value of that flux to start to pull things down.

For atmosphere to the terrestrial biosphere, ignoring the return flux due to fire, don't experiments like the FACE studies show that higher CO2 stimulates additional growth for a few years and then starts to tail off, so does not higher uptake stop pretty fast if there is no longer a gradient, etc.

Is there a good well-documented resolution about this where theory and models and observations agree what happens if one basically heads down toward zero emissions by 2050 or so?

Mike MacCracken


On 8/12/21 4:46 PM, John Harte wrote:
Kevin, you write: "Finally, and as you point out, carbon removal will be slow. The natural rate of removal is so slow as to not be measurable against CO2 emissions”.

The current rate of removal of atmospheric carbon dioxide by natural marine and terrestrial processes is about 5 Gt(C)/year, which is about half of current annual anthropogenic emissions. 

That hardly seems to be unmeasurably slow!

Were we to cease emissions today those natural sinks would persist but with diminishing strength in the future as the atmospheric level draws down. The sinks will not get the atmosphere down to a pre-industrial CO2 level of course, but they will nevertheless make a big difference.  

Among the most important things we can do is to stop degrading those natural sinks … protecting them is cheaper, would accomplish more than engineering artificial sinks, and would also provide  numerous co-benefits.  


John Harte
Professor of the Graduate School
Ecosystem Sciences
ERG/ESPM
University of California
Berkeley, CA 94720









--
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email to geoengineerin...@googlegroups.com.

Bruce Melton -- Austin, Texas

unread,
Aug 12, 2021, 8:15:09 PM8/12/21
to CarbonDiox...@googlegroups.com

Olivier Boucher sent me this excellent article earlier this year that has some broad answers about fate of sequestered CO2 as we restore our climate.
(attached) Boucher et al., Reversibility in an Earth System model in response to CO2 concentration changes, Environmental Research Letters, May 9, 2012.

The slow argument is something many of us have made for years; oceans bury CO2 deep, forests sequester for the life of trees...  Reemissions will generally happen as Mike says, once we lower atmospheric CO2 enough that the sequestering reservoirs can vent, but even then those emissions will not be all that meaningful. The reason why is we have to lower atmospheric CO2 down to near 350 ppm to get back to CO2 equilibrium. Hansen's, "Young People's Burden..." says CO2 equilibrium at 350 ppm CO2 is 0.85 C (+/-). By the time we can get to anywhere near 350 ppm, we will have scaled our atmospheric removal infrastructure so large that reemissions of recently sequestered CO2 will be much less than what our infrastructure is capable of addressing. Or if we fail to create this gigascaled infrastructure, we will be rewarded with unrecoverable scenarios.

On natural systems sequestration, I have been filming impacts to natural systems for 14 years. I also volunteered with a small team at Sierra Club writing new climate policies 2019/2020 that included substantial content on natural systems preservation, adaptation, restoration and enhancement. Fundamentally, when we warmed above about 0.5 C, we warmed above the evolutionary boundaries of our Earth systems and they began collapsing. This is a critical piece of knowledge that is lost on most. When a natural systems changes beyond their evolutionary boundary conditions, what happens? The systems must reevolve. This reevolution includes collapse of some sort, fast or slow, fiery or droughty, with loss or reversal of environmental services like GHG sequestration.

I have seen this happening across North America since 2007 with impacts today wildly more extreme, and today we are seeing the science that reflects these collapses:

Permafrost collapse - Natali et al., Large loss of CO2 in winter observed across the northern permafrost region, Nature Climate Change, October 21, 2019.
Amazon collapse - Gatti et al., Amazonia as a carbon source linked to deforestation and climate change, Nature, July 14, 2021.
Canadian Forest Collapse - The State of Canada's Forests, Adapting to Change, Canadian Forest Service, 2020.
(Canada - see also - https://climatediscovery.org/canadas-forests-have-flipped-from-carbon-sink-to-greenhouse-gas-emissions/)

Science is slow and we are now in the rapidly changing phase of climate impacts and certainly degradation is much farther along than the data from the above implies. Our ability to enhance or restore, or even maintain our natural systems environmental services with current warming really needs some deep soul searching.

B


Bruce Melton PE
Director, Climate Change Now Initiative, 501c3
President, Melton Engineering Services Austin
8103 Kirkham Drive
Austin, Texas 78736
(512)799-7998
ClimateDiscovery.org
MeltonEngineering.com
Face...@Bruce.Melton.395
Inst...@Bruce.C.Melton
The Band Climate Change
Twitter - BruceCMelton1


Boucher et al., Reversibility in an Earth System model in response to CO2 concentration changes, Environmental Resaerch Letters, May 9, 2012.pdf

Kevin Lister

unread,
Aug 13, 2021, 5:47:04 AM8/13/21
to John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering
Hi John, I see that Mike has gotten to the answer while I've been drafting my response, but here are some further numbers and positions to support his argument and the point that I was making...... 

Point 1

There is nearly perfect correlation between CO2 concentration and fossil fuel consumption, with R^2=0.9991 from 1965 to 2019. 1965 is when BP started collecting the best reliable set of fossil fuel consumption. The relationship is likely to now be broken with the forest fires and other large scale CO2 releases - I not gotten round to checking. 

image.png

Atmospheric CO2 concentration started rising immediately at the start of the industrial revolution, when emissions were much lower than they are today. So we can be reasonably sure that the straight line relationship above can be extrapolated back to the start of the industrial revolution. Therefore, at best,  the rate of permanent CO2 removal must be constant otherwise the relationship would not be a straight line, and it must be very small otherwise the atmospheric concentrations would not have responded so quickly at the start of the industrial revolution. 

Point 2

From the slope of the line and the high correlation, we can get a reasonable prediction of what change in atmospheric CO2 levels equates to CO2 emissions. We also know that the annual cycle is about 8ppm, so from this we can conclude that approximately 32,059 million tonnes of carbon are absorbed from the atmosphere each summer, but these are emitted back in the winter. So this cycle is in the same order of magnitude that you have suggested, but this is not permanent Carbon storage. Getting carbon deep into the ground where it does not come back up is what we need to do, but this is different from the annual cycle and a much slower process.  From recollection IPCC AR5 gave a figure of 0.2 million tonnes of permanent carbon removal per year, and this concurs with the observations above.

Point 3

The extremely low rate of permanent removal is independently verified in the data from the Vostok Ice Core which shows consistent CO2 removal over the last 4 interglacial cycles. When applying this rate of permanent removal to the 450ppm, we get a 250,000 year time period to return to the upper limits of past CO2 concentrations in interglacial cycles, see graph below:

image.png

 
So, finally.....

I absolutely agree with you that we must protect and enhance natural sinks, but even when doing this, it is unlikely that it will result in a CO2 removal rate that would enable safe levels to be permanently maintained in a time period that is not measurable in hundreds of thousands of years. 

So... 

We need to find reliable albedo enhancement methodologies that we can deploy for the ultra long term and that are quickly able to return temperatures back to those around 1980 when self amplifying feedback mechanisms were first triggered. 


Kevin








On Thu, Aug 12, 2021 at 9:46 PM John Harte <jha...@berkeley.edu> wrote:
Kevin, you write: "Finally, and as you point out, carbon removal will be slow. The natural rate of removal is so slow as to not be measurable against CO2 emissions”.

The current rate of removal of atmospheric carbon dioxide by natural marine and terrestrial processes is about 5 Gt(C)/year, which is about half of current annual anthropogenic emissions. 

That hardly seems to be unmeasurably slow!

Were we to cease emissions today those natural sinks would persist but with diminishing strength in the future as the atmospheric level draws down. The sinks will not get the atmosphere down to a pre-industrial CO2 level of course, but they will nevertheless make a big difference.  

Among the most important things we can do is to stop degrading those natural sinks … protecting them is cheaper, would accomplish more than engineering artificial sinks, and would also provide  numerous co-benefits.  


John Harte
Professor of the Graduate School
Ecosystem Sciences
ERG/ESPM
University of California
Berkeley, CA 94720








On Aug 12, 2021, at 5:01 AM, Kevin Lister <kevin.li...@gmail.com> wrote:

Michael MacCracken

unread,
Aug 13, 2021, 8:48:58 AM8/13/21
to Kevin Lister, John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering

Hi Kevin--On your point 2, I think the amount taken up each season that you have is mistaken. The global concentration change by 8 ppm through the season is only happening in the Northern Hemisphere. And I think in terms of atmospheric loading, the total global loading is roughly 2 GtC per ppm. So, when I do the calculation of what the Mauna Loa 8-10 ppm seasonal variation in the CO2 concentration implies, I get 8-10 GtC/year for the net seasonal greening of the Northern Hemisphere, not the 32 GtC/year that you are getting. Now, my number is for the "net" and the "gross" uptake would be greater as there is decay going on, so perhaps I missed what you were saying.

And if we say the emissions are 10 GtC/year, and then that the airborne fraction is holding steady at about a half (or a bit less), one can divide the emissions by 4 to get the rough increase per year in ppm, so roughly 2.5 ppm/year.

As to how to interpret all of this, these relations are with steadily rising emissions, and the question to get to is what can this tell us when emissions are going down and eventually to zero or negative. Is the near steadiness of the ratios due to the fact that the total concentration is rising compared to preindustrial (and upper to deep ocean flux is likely related to this as deep ocean has 1000 year cycle time) and so that flux will continue for some time, or is the steadiness due to the fact that each year's emissions are rising (which may apply to the terrestrial biosphere uptake as FACE experiments (i.e., field experiments imposing plants to high levels of CO2) tend to saturate in a few years (at least for shrubs, if perhaps not for forests), perhaps being limited by the amount of nutrients and water that can be drawn up to take advantage of the higher CO2 concentration.

I am not an expert on all of this and am assuming some good modeling has been done. I'm just saying I've heard a range of views and would like to understand better as I am pretty wary of just applying rules of thumb we draw mainly from a period of steadily, even exponentially, rising emissions to the situation of declining emissions in a warmer world when we have wildfires and pests tearing ecosystems apart.

Mike

Kevin Lister

unread,
Aug 13, 2021, 1:32:54 PM8/13/21
to John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering
Yes Mike, you are absolutely correct to point out that the cycle at Mauna Loa applies only to the Northern hemisphere. But the Southern hemisphere also has a cycle and the total amount of CO2 absorbed will be the sum of them both. However, I have not compared the magnitude of the Southern hemisphere annual cycle with the Northern, and for simplicity assumed them to be both the same and it irrelevent that they happen in counter phase. The number that I have calculated will effectively be an approximation to the gross annual absorption and so will be removing CO2 that has been emitted by the ecosystem over winter as well as anthropogenic emissions. 

From the relationship between cumulative emissions and CO2 concentration, I use 1 million tonnnes of CO2 emissions gives a rise of CO2 concentration of 7.2642E-05 ppm.  There is a figure in the AR6, so I will need to dig this out to see how it compares. 

Interesting, your comments have encouraged me to look at the numbers in further detail. The first figure I used for the amplitude of the annual cycle was 8.7. However this was the rise and not the drop and I naively assumed these would be the same. The drop in CO2 is 6.12ppm so equating to ~22,000million tonnes of CO2 removal. 

This discrepancy pricked my curiosity further, so I've looked at the annual cycles since 1965 when accurate fossil fuel consumption records began and compared the rises and the falls, and then calculating a corrected annual drop in PPM by adding the expected rise in PPM during the year from emissions, and calculating a corrected rise in PPM by subtracting expect rise in PPM during the year from emissions, see below:

year CO2 cycle drop CO2 rise Annual CO2 emissions expected rise in CO2 due to emissions Corrected drop corrected rise
1965 4.86 6.71 11,194 0.81 5.67 5.90
1966 5.91 6.9 11,709 0.85 6.76 6.05
1967 5.69 6.26 12,068 0.88 6.57 5.38
1968 5.32 7.09 12,726 0.92 6.24 6.17
1969 5.56 6.35 13,519 0.98 6.54 5.37
1970 5.03 5.82 14,269 1.04 6.07 4.78
1971 5.56 6.71 14,766 1.07 6.63 5.64
1972 5.14 7.55 15,468 1.12 6.26 6.43
1973 5.3 6.01 16,315 1.19 6.49 4.82
1974 5.98 6.7 16,229 1.18 7.16 5.52
1975 5.55 6.42 16,249 1.18 6.73 5.24
1976 6.01 8.05 17,129 1.24 7.25 6.81
1977 5.63 6.82 17,676 1.28 6.91 5.54
1978 5.68 6.87 17,978 1.31 6.99 5.56
1979 5.27 7.54 18,556 1.35 6.62 6.19
1980 5.42 6.96 18,389 1.34 6.76 5.62
1981 6.09 7.75 18,152 1.32 7.41 6.43
1982 6.35 7.64 17,977 1.31 7.66 6.33
1983 5.79 7.38 18,144 1.32 7.11 6.06
1984 6.2 7.57 18,811 1.37 7.57 6.20
1985 5.84 7.45 19,173 1.39 7.23 6.06
1986 6.06 7.67 19,508 1.42 7.48 6.25
1987 5.62 7.66 20,109 1.46 7.08 6.20
1988 5.15 6.86 20,771 1.51 6.66 5.35
1989 5.87 7.27 21,166 1.54 7.41 5.73
1990 6.01 7.81 21,290 1.55 7.56 6.26
1991 6.79 7.25 21,280 1.55 8.34 5.70
1992 6.62 7.26 21,354 1.55 8.17 5.71
1993 6.09 7.58 21,419 1.56 7.65 6.02
1994 6.05 8.14 21,653 1.57 7.62 6.57
1995 5.8 7.19 21,896 1.59 7.39 5.60
1996 5.62 7.15 22,527 1.64 7.26 5.51
1997 6.38 9.18 22,741 1.65 8.03 7.53
1998 5.48 6.95 22,793 1.66 7.14 5.29
1999 6.02 6.88 23,116 1.68 7.70 5.20
2000 4.91 6.91 23,668 1.72 6.63 5.19
2001 5.66 7.49 23,982 1.74 7.40 5.75
2002 5.14 7.99 24,502 1.78 6.92 6.21
2003 5.4 7.53 25,716 1.87 7.27 5.66
2004 6.52 8.36 27,044 1.96 8.48 6.40
2005 5.81 8.32 28,142 2.04 7.85 6.28
2006 6.06 7.66 29,019 2.11 8.17 5.55
2007 5.68 7.6 30,048 2.18 7.86 5.42
2008 5.51 7.2 30,337 2.20 7.71 5.00
2009 5.8 8.65 29,719 2.16 7.96 6.49
2010 6.21 7.38 31,058 2.26 8.47 5.12
2011 5.25 7.82 31,978 2.32 7.57 5.50
2012 5.77 8.75 32,317 2.35 8.12 6.40
2013 6.25 8.27 32,800 2.38 8.63 5.89
2014 6.52 8.68 32,845 2.39 8.91 6.29
2015 6.31 10.07 32,804 2.38 8.69 7.69
2016 6.67 8.62 32,914 2.39 9.06 6.23
2017 6.27 7.86 33,243 2.41 8.68 5.45
2018 5.73 9.13 33,891 2.46 8.19 6.67
2019 6.12 8.79 34,169 2.48 8.60 6.31



I then plot the trends of the corrected values, the CO2 annual drops first and the CO2 annual rises second.

image.png

There are a couple of things that are immediately obvious:

  • There is strong correlation between time and annual CO2 removal, with a correlation coefficient of 0.84. thus potentially indicating that the planet is absorbing more CO2 in response to rising atmospheric concentrations.  
  • The high peaks above the trend in 1992 and 2014 coincide with the Mount Pinatubo and Mount Klyichevshoy which I understand was a significant eruption.


image.png

The immediately obvious thing from this are:

  • The peaks rises in 1998 and 2014 which coincide with El Ninos
  • There is no rise in natural emissions that is equivalent to the rise in uptake.

In answer to John's points below:

I am clear on Mike's comments and not in disagreement with them.

I'm not clear on the point you are making in response to Point 1. The conclusion that I draw from the near perfect correlation, and in support of Mike's comment, is that there is no evidence of CO2 being permanently removed from the ecosystem in a climatically significant way or there being unfilled sinks that have the capacity to draw down CO2, however the comparison of the up swing and down swings in the CO2 cycle may offer a slight challenge to this position and may allow a more refined way to quantify what potential may exist and thus quantify the questions that Mike was asking. 

On point 2 - I have addressed this above.

On point 3 - The rates of interest in Vostok data are the recovery rates. As I said previously, these are extremely consistent and when extrapolating from the CO2 levels that we are heading towards, it will take in the order of 250,000 years for CO2 to fall to the safe levels. I am assuming that the same rates of recovery will apply to today which is potentially flawed for the reason that you pointed to of feedback mechanisms being triggered. Thus any CO2 recovery could be even slower. 

Given this data, I cannot see any way that we can rely on CO2 naturally falling to 380ppm in any time soon even in the unlikely event that we are able to get to zero carbon, even with all the protection and enhancement of natural sinks that we can manage. As you say, we need urgent R&D on the cooling technologies. 

In particular the CO2 release to the atmosphere that is evident in the second graph above shows the importance of cooling the planet as a means to stop CO2 rises.

Kevin
 



On Fri, Aug 13, 2021 at 4:06 PM John Harte <jha...@berkeley.edu> wrote:
Kevin, I believe you have misinterpreted Mike’s comment.  He was adding clarity to the fundamental issue, which he simply stated as follows. Is the large carbon sink that we observe in recent years (large in the sense that the observed 5 Gt of carbon removed from the atmosphere each recent year is ~ half of recent annual emissions) driven by each year's emissions or by the amount by which the current atmosphere is out of physical and chemical equilibrium with the current ocean/biosphere.  

Your Point 1.  Under either of the two options above (sink driven by annual emissions versus sink driven by disequilibrium between atm. and ocean/land) you can explain the data you show.
Point 2.  You seem to be confusing the annual photosynthesis/decomposition cycle, which has opposing phase between hemispheres, with the interannual trends. 
Point 3: Relative to the rates of both temperature and CO2 changes in the Vostok record, the rates are much higher in recent decades, invalidating your conclusion.

The models I have seen and worked with suggest that if we zero out emissions today, then a year from now the atmospheric CO2 level will be about 2 to 2.5 ppm lower than it is now.  And that over the next several decades the sink strength will gradually diminish to zero as the atmosphere approaches equilibrium with the oceans and the terrestrial sinks saturate.  We won’t get down to 300 ppm that way, but down to 380 ppm is quite plausible and 350 is possible.
 
Protecting and enhancing these natural sinks, along with rapid transition to clean energy, seems to me to provide the most bang for the buck.  What keeps me up at night is the concern that warming and other anthropogenic activity will trigger feedbacks that wipe out the natural sinks and create new sources. At the same time, R&D on back-up technologies in case the feedbacks kick in also makes sense. 



 

John Harte
Professor of the Graduate School
Ecosystem Sciences
ERG/ESPM
University of California
Berkeley, CA 94720








On Aug 13, 2021, at 2:46 AM, Kevin Lister <kevin.li...@gmail.com> wrote:

Hi John, I see that Mike has gotten to the answer while I've been drafting my response, but here are some further numbers and positions to support his argument and the point that I was making...... 

Point 1

There is nearly perfect correlation between CO2 concentration and fossil fuel consumption, with R^2=0.9991 from 1965 to 2019. 1965 is when BP started collecting the best reliable set of fossil fuel consumption. The relationship is likely to now be broken with the forest fires and other large scale CO2 releases - I not gotten round to checking. 

<image.png>

Atmospheric CO2 concentration started rising immediately at the start of the industrial revolution, when emissions were much lower than they are today. So we can be reasonably sure that the straight line relationship above can be extrapolated back to the start of the industrial revolution. Therefore, at best,  the rate of permanent CO2 removal must be constant otherwise the relationship would not be a straight line, and it must be very small otherwise the atmospheric concentrations would not have responded so quickly at the start of the industrial revolution. 

Point 2

From the slope of the line and the high correlation, we can get a reasonable prediction of what change in atmospheric CO2 levels equates to CO2 emissions. We also know that the annual cycle is about 8ppm, so from this we can conclude that approximately 32,059 million tonnes of carbon are absorbed from the atmosphere each summer, but these are emitted back in the winter. So this cycle is in the same order of magnitude that you have suggested, but this is not permanent Carbon storage. Getting carbon deep into the ground where it does not come back up is what we need to do, but this is different from the annual cycle and a much slower process.  From recollection IPCC AR5 gave a figure of 0.2 million tonnes of permanent carbon removal per year, and this concurs with the observations above.

Point 3

The extremely low rate of permanent removal is independently verified in the data from the Vostok Ice Core which shows consistent CO2 removal over the last 4 interglacial cycles. When applying this rate of permanent removal to the 450ppm, we get a 250,000 year time period to return to the upper limits of past CO2 concentrations in interglacial cycles, see graph below:

Greg Rau

unread,
Aug 13, 2021, 5:04:22 PM8/13/21
to John Harte, Mike MacCracken, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering
Kevin, Assuming your annual pCO2 drops and rises have been accurately corrected for anthro emissions (but you only accounted for fossil emissions and not anthro land use emissions?), I see a significant strenghtening of the CO2 sink(s) and a very modest increase in "natural" emissions:
Inline image

If valid, this says that sinks are strengthening and natural emissions are largely unaffected. This is suprising since warming should be increasing respiration and bio C loss, and reduing seawater CO2 solubility, weakeing sinks. On the other hand increasing air pCO2 will drive more CO2 into undersaturated seawater and will "fertilize" plants. Your data says that the latter factors are dominating, and that significant CO2 loss from bio and ocean C stores has yet to kick in(?)
Greg

James Butler - NOAA Federal

unread,
Aug 13, 2021, 6:45:38 PM8/13/21
to Greg Rau, John Harte, Mike MacCracken, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering
Greg et al.,

Just FYI.  We've been able to measure COS in the atmosphere to help separate photosynthesis from respiration.  Lei Hu et al. just published a paper putting this approach to work just to answer this question on ecosystem uptake and ecosystem respiration.  ( https://www.pnas.org/content/118/33/e2103423118 ).  It's one of our first that digs deep into this question using long-term observations of COS along with CO2.

Jim


James.H.Butler, Director
NOAA Global Monitoring Laboratory
325 Broadway
Boulder CO 80305

Ph: 303-497-6898


Greg Rau

unread,
Aug 13, 2021, 7:19:20 PM8/13/21
to James Butler - NOAA Federal, John Harte, Mike MacCracken, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering
Thanks, Jim. To quote the abstract:
"In spring to midsummer, when GPP is most strongly correlated with soil temperature, our results suggest the warming-induced increases of GPP likely exceeded the increases of ER over the past four decades. In autumn, however, increases of ER were likely greater than GPP due to light limitations on GPP, thereby enhancing autumn net carbon emissions. Both effects have likely contributed to the atmospheric CO2 SCA amplification observed in the ABR."
In contrast, Kevin's analysis says the increase  in seasonal pCO2 amlification has been driven by increasing sinks.  As to which sinks have increased, land bio and/or ocean, may I suggest that the CO2 13C/12C record at Mauna Loa and elsewhere would be useful.   
Regards,
Greg

Michael MacCracken

unread,
Aug 13, 2021, 9:48:12 PM8/13/21
to Greg Rau, John Harte, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering

Hi Greg--For the airborne fraction to be roughly constant as emissions have gone up, indeed there has to be an increased rate of uptake by the land and oceans (though the ratio between the two has shifted a bit). The question is if the increases are due to the overall increase in the CO2 concentration or to the increment being created each year (or over past couple of years, etc.). If it is the former, then one might expect the fluxes (i.e., sinks) to stay up and only go down slowly such that natural processes would pull the CO2 concentration down say 80 ppm out of the 140-150 ppm (so about a half) that we have gone up. If the latter, rather than the bounce-back being half or so, it might be really quite slow. Viewed this way, it would seem to have a factor of 2 or so influence on hos much CDR would be needed to restore the radiative forcing of the early 20th century or so.

Mike

Michael MacCracken

unread,
Aug 13, 2021, 10:07:22 PM8/13/21
to Kevin Lister, John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering

Hi Kevin--Apologies for delayed response--dealing with improving defense of our home against some increasingly drenching thunderstorms we've been having.

On your first paragraph, because there is much less land, especially in the mid-latitudes, in the Southern Hemisphere, the seasonal cycle of CO2 is quite small--as an example, you can see the concentration variation in Australia at https://theconversation.com/southern-hemisphere-joins-north-in-breaching-carbon-dioxide-milestone-59260 . I'm not an expert, but quite likely at least a bit of the small variation may be from the variation in the NH being carried into the SH--and time scale for such spread is of order 6 months. So, there is just very little seasonal variation of CO2 in SH as there is just not much land for seasonal variations in vegetation. This said, there is surely some growth going on--likely mostly steady through the year (on average), but it can't be too much as the SH average concentration is only a bit lower than the NH concentration, and this is due to most sources being in the NH and the time constant for mixing to SH (something like 6-12 months).

I am not sure that the paleo-analog is relevant, but interesting to consider. What the overall record suggests to me is that it takes a lot longer to build up ice sheets than for them to collapse (likely relevant to thinking about Greenland and Antarctic ice sheets--and perhaps an interesting analog for nation building). And temperature cools more slowly than it warms. The CO2 concentration seems pretty well correlated with the temperature in the Vostok core, with a bit of a lag, which would seem roughly consistent with the atmospheric mixing into the ocean as its temperature drops. So, the question is what is determining the slow rate of cooling--with the CO2 lagging a bit, it would not that the CO2 change is controlling the temperature, and instead what is limiting cooling is the time it takes to build up ice sheets and, as some have suggested, the time it takes for what cold meltwater there is to cool the ocean, etc. So, I'm not convinced the rate of CO2 increase determined this way gives insight into how the future CO2 may come down rather than, perhaps, how slow the process of cooling the ocean will be, and as long as the ocean is pretty warm, it is just not clear where the excess CO2 will go (especially given that the overturning circulation slows with warming). So, while I'm hesitant to use the exact long time constant you get, but it sure does seem to indicate that the CO2 concentration going down can really only happen as the ocean cools--and that will take time. This does not rule out some sort of adjustment of the type John Harte is suggesting, but how large it will be is the question that will determine how much CDR has to be done (or perhaps we use SRM to accelerate ocean cooling and this will help pull the CO2 concentration down as well--presuming we've gotten emissions to zero.

Mike

Robert Tulip

unread,
Aug 14, 2021, 1:01:36 AM8/14/21
to John Harte, Carbon Dioxide Removal, geoengineering

Hi John, your points below raise essential questions about the justification for CDR compared to the main current policy focus on net zero through decarbonisation.

 

My understanding, which may be wrong, is that your point 4, about the 5 Gt(C) now removed each year by natural processes, is not relevant to a future net zero scenario

 

The 5 GTC is removed each year mainly because the 10 GTC/y emission increase creates a disequilibrium with the ocean, so most of that extra CO2 is stored as carbonic acid in the sea.  If we stopped adding 10 GTC/y, there would be no forcing for this ongoing increase of ocean acid, and the 5 GTC removal each year would mostly stop as well. 

 

The problem with your argument, as I understand it, is that prior to the emission era the CO2 level was stable at 280 ppm, but your 5 GTC/y natural removal figure implies it should have been falling by 2ppm/y.

 

If we get to net zero just by decarbonising, we will sit at 600 ppm CO2e, given the future GHG emissions to 2050.  In this Gedank, without CDR, there would then be nothing to pull that GHG level down to the Holocene norm.  The ongoing 600 ppm equivalent level will cause rapid sea level rise and other ongoing catastrophes. 

 

So the strategy needs to be immediate planetary brightening to slow down extinction and weather extremes, alongside ramping up CDR, rather than putting all the eggs in the decarbonisation basket. 

 

The IPCC just does not see or acknowledge this logic, let alone refute it.  It is a security and psychology crisis produced by the bullying that creates excessive scientific caution.

 

Net zero has to be seen only as a milestone on the path to massive carbon removals, not as an end in itself.  So the main input to achieving net zero has to be CDR, not decarbonisation, to create the momentum and trajectory to continue toward climate stability and repair.  But before that, the world urgently needs SRM as a tourniquet to stop the patient bleeding to death before we reach the CDR operating table.

 

Robert Tulip

 

From: John Harte <jha...@berkeley.edu>
Sent: Saturday, 14 August 2021 5:32 AM
To: Kevin Lister <kevin.li...@gmail.com>
Cc: Mike MacCracken <mmac...@comcast.net>; Robert Tulip <rtuli...@yahoo.com.au>; Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>
Subject: Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

Kevin, which of the following do you think is (are) incorrect:

 

1.  In recent years annual anthropogenic emissions are approximately 10 Gt(C)/y

2.  Each year, in recent years, the atmospheric level of CO2 increases by approximately 2.5 ppm.

3.  A Gt(C) is equivalent to approximately 2 ppm.

4.  10 - 2*2.5 = 5 Gt(C) removed each year

5.  5/10 is not a tiny, “not measurable” fraction of emitted carbon.

 

 

 

 

 

<image.png>

 

There are a couple of things that are immediately obvious:

 

  • There is strong correlation between time and annual CO2 removal, with a correlation coefficient of 0.84. thus potentially indicating that the planet is absorbing more CO2 in response to rising atmospheric concentrations.  
  • The high peaks above the trend in 1992 and 2014 coincide with the Mount Pinatubo and Mount Klyichevshoy which I understand was a significant eruption.

 

 

<image.png>

Olivier Boucher

unread,
Aug 14, 2021, 4:51:58 AM8/14/21
to Carbon Dioxide Removal
Hello,

I know this is not related to the argument you're having and that everyone (including IPCC) does it, but I think step 5 is inappropriate in the sense that the numerator and the denominator do not relate directly to each other. The denominator is the CO2 emissions in a given year. The numerator is the C sink is essentially a function of the CO2 concentration and its growth rate (see Fig 3 in https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020EF001967), hence it depends on the history of CO2 emissions prior to that given year. Of course mathematically there is nothing wrong in ratioing these two numbers but physically I find this number or its complement, the "airborne fraction", to be a pretty ill defined quantity. It is fine to compare the number and one can make a hand-waiving argument that natural sinks keep up with the emissions (or not) when emissions keep increasing. But it becomes less meaningful when emissions are non-monotonic. If emissions were suddenly halved or doubled, the natural sinks would carry on (they may change a bit because of this dependence on the atmospheric growth rate though I am not sure by how much) and the airborne fraction would be much less or much more. Yet it would not tell us much on the changing efficacy of natural sinks. 

Best,

Olivier 


De: "John Harte" <jha...@berkeley.edu>
À: "Kevin Lister" <kevin.li...@gmail.com>
Cc: "Mike MacCracken" <mmac...@comcast.net>, "Robert Tulip" <rtuli...@yahoo.com.au>, "Carbon Dioxide Removal" <CarbonDiox...@googlegroups.com>, "geoengineering" <geoengi...@googlegroups.com>
Envoyé: Vendredi 13 Août 2021 21:32:23
Objet: Re: [geo] RE: IPCC AR6 Summary for Policymakers

Brian Cady

unread,
Aug 14, 2021, 8:36:23 AM8/14/21
to Olivier Boucher, Carbon Dioxide Removal
Are others as worried as Sam Carana about the quality of IPCC AR6 WG1's work?
Sam Carana responded to IPCC AR6 WG1 thusly:
'
IPCC REPORT: BASELINE STRUGGLE
The Intergovernmental Panel on Climate Change (IPCC) has just released a new report, the Working Group I contribution to the Sixth Assessment Report (AR6). When reading the report, the question comes up: Is the IPCC seeking to downplay the dire situation we're in, again? One of the first issues that comes up is the baseline. The IPCC selects 1850–1900 as a baseline, as it did before (in SR1.5). This isn't pre-industrial. The Paris Agreement calls for pre-industrial as a base.
During 1850 to 1900, more livestock, forest clearing and wood burning resulted in growth in emissions of black carbon, brown carbon, dust, methane and carbon monoxide, which all can temporarily drive up temperatures. Additionally, there was little impact yet of the sulfur aerosols associated with increased fossil fuel burning from 1900. Trends drawn from this base can therefore look flatter than they would have looked if drawn from a genuinely pre-industrial base, or even from the early 1900s as base. The IPCC appears to say that there is only a 50% chance that 1.5°C will be crossed by 2030. Is this a deliberate effort to create the perception that there was enough carbon budget left to be divided among polluters, to let them comfortably keep adding further pollution for another decade or more?
Instead, the IPCC could have concluded that there hasn't been a carbon budget for a long time and that there are indications that the 1.5°C threshold has long been crossed. When calculating the temperature rise through 2020 and going back one century, NASA data show a 1.29°C rise from 1920, which is a conservative figure, i.e. 0.1°C can be added to translate NASA's sea surface temperatures into ocean air temperatures and another 0.1°C can be added for higher polar anomalies. So, that already brings the temperature rise up to about 1.5°C and this isn't the full rise from pre-industrial by a long shot.
The IPCC does mention that from 1750 to 1850–1900 there was a global surface temperature rise of up to 0.3°C, but then excludes this rise, sticking to its selection of 1850-1900 as base. The IPCC also uses seasonally-biased data for the temperature rise before 1750, making it look as if temperatures didn't rise before 1750, whereas it makes sense to add a 0.29C rise for the period from 3480 BC to 1520, and a further 0.2°C for 1520 to 1750.
Adding up the different elements thus gives a total rise from pre-industrial that could be as high as 1.29°C + 0.1°C + 0.1°C + 0.3°C + 0.2°C + 0.29°C = 2.28°C....
'

Curiously,

Brian
-


H simmens

unread,
Aug 14, 2021, 9:11:43 AM8/14/21
to Brian Cady, Olivier Boucher, Carbon Dioxide Removal

Brian,

Should we be worried about what baseline is used or is it 
more relevant to focus on how much higher the temperature will go from the 7.2°C average planetary temperature? 

Or should the focus be on atmospheric CO2 concentrations?

After all the longtime UNFCCC established goal is to stabilize GHG concentrations at a level that would prevent dangerous anthropogenic interference with the climate system. 

Or focus on C02E though I understand the IPCC does not find that to be a particularly useful metric. 

Or is the most important indicator the Earth Energy Imbalance. It is not clear to me why more attention isn’t given to the truly alarming EEI doubling that occurred between 2005 and 2019. 


Much of what I’ve learned about the EEI I’ve gotten from reading James Hansen. 

I’m no scientist and have never been able to truly understand which metric is appropriate for which purpose. 

Herb



Herb Simmens
Author A Climate Vocabulary of the Future
@herbsimmens

On Aug 14, 2021, at 8:36 AM, Brian Cady <brianc...@gmail.com> wrote:



Anton Alferness

unread,
Aug 14, 2021, 11:38:20 AM8/14/21
to H simmens, Brian Cady, Olivier Boucher, Carbon Dioxide Removal
Robert - 

Your line "It is a security and psychology crisis produced by the bullying that creates excessive scientific caution" rings true for me. I have the same observation that I've been troubled by but haven't been able to distill it as well as you have here. I've also been unsure if scientists see it because it's the pond they swim in. Add to that the real likelihood that some in the scientific community may be offended. I've been communicating that one of the problems we have in society is in fact the scientific community (more so the oceanography community), specifically the psychological and operational paradigm of "study, don't touch" which is not how engineers think or operate... combined with the severe and aggressive competitiveness that does not lend itself to collaboration and problem solving. And you are right Robert, this creates excessive caution. How many weeks in a row has there been a new scientific paper published that essentially says "things are worse, faster than previously understood" = ? I'll give you the answer: EVERY SINGLE WEEK for the past 20 years. 

The bright spot with the IPCC report is that for most of the uneducated society, it is a more realistic, more graduated assessment - which they need to hear. 

-Anton 

Robert Tulip

unread,
Aug 14, 2021, 11:47:37 AM8/14/21
to H simmens, Brian Cady, Olivier Boucher, Carbon Dioxide Removal

Thanks Herb for drawing attention to Earth Energy Imbalance as a key climate indicator, with the doubling since 2005.

 

I would like to know if Earth Energy Imbalance credits could work like carbon credits.

 

Could the impact of a climate change initiative on radiative forcing be a better way than carbon emission credits for government subsidy and markets to measure climate effects?

 

Such a shift to the overall planetary heat impact as the basis of value would make cooling action to increase albedo more commercially attractive.

 

That might support action on Sam Carana’s suggestion there hasn't been a carbon budget for a long time and the 1.5°C threshold has long been crossed.

 

Regards, Robert

Kevin Lister

unread,
Aug 14, 2021, 5:12:50 PM8/14/21
to Greg Rau, John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering, olivier...@ipsl.fr, Douglas MacMartin
Hi Greg et al, 


Thanks for your comments, 

These results are not what I expected at the start of this debate!!!

As you say, it looks like the sinks have strengthened and the sources have remained relatively fixed as CO2 concentrations have risen. I am hugely surprised about the strength of the correlation between the strength of the sources and the time (r=0.83), along with an equivalent correlation when CO2 concentration is the independent variable. It might well be that this is a measure of the resilience of the ecosystem and life, even when so much is thrown at it.  I am in the middle of calculating how long this differential in rates would take to return the climate to safe conditions, the first cut being about 8,000 years. However, as warned by John, this may not persist once the full suite of feedback mechanisms have kicked in, and as per the discussion that Mike alluded to on the Vostok Ice core data, there are critical issues related to ocean heat that can diminish the strength of the CO2 sinks. 

This somewhat crude assessment certainly supports the observations that Oliver pointed to in his abstract.  Of note, is that the sources come in surges, driven by El Ninos, and perhaps a real target of any SRM would be to prevent El Ninos happening, or at least to mitigate their effect. 

As Mike and Doug have correctly pointed out, this applies to the Northern hemisphere, contrary to my initial assertion. 

Similar data for the Crozet Islands in the Indian Ocean is below along with equivalent graphs. The southern Hemisphere has a  much reduced annual oscillation, and the rises can be eliminated; neither the rises or the falls are showing any response to changes in CO2 emissions. It's not clear what this is showing, but perhaps it might indicate that terrestrial uptake could be more important as a sink than oceans, but again that is counter to my intuition, and any thoughts on this would be welcomed. 



  fall  rise Expected rise due CO2 emissions corrected drop correct rise
1992 2.56 3.2 1.55 4.11 1.65
1993 1.25 2.4 1.56 2.81 0.84
1994 1.01 2.11 1.57 2.58 0.54
1995 1.62 3.04 1.59 3.21 1.45
1996 1.08 2.46 1.64 2.72 0.82
1997 1.52 1.96 1.65 3.17 0.31
1998 -0.06 3.71 1.66 1.60 2.05
2003 0.36 2.79 1.87 2.23 0.92
2004 0.91 2.54 1.96 2.87 0.58
2005 0.52 2.63 2.04 2.56 0.59
2006 0.41 2.05 2.11 2.52 -0.06
2007 0.28 2.52 2.18 2.46 0.34
2008 0.21 2.02 2.20 2.41 -0.18
2010 0.95 3.13 2.26 3.21 0.87
2011 0.74 2.22 2.32 3.06 -0.10
2012 0.83 3.14 2.35 3.18 0.79
2013 0.61 3.47 2.38 2.99 1.09
2015 0.54 3.07 2.38 2.92 0.69
2016 0.48 3.61 2.39 2.87 1.22
2017 1.27 3.25 2.41 3.68 0.84
2018 0.58 2.9 2.46 3.04 0.44
2019 0.95 3.71 2.48 3.43 1.23


image.png

image.png


On John's email on what I think to be correct and incorrect
1.  In recent years annual anthropogenic emissions are approximately 10 Gt(C)/y - agree
2.  Each year, in recent years, the atmospheric level of CO2 increases by approximately 2.5 ppm - agree
3.  A Gt(C) is equivalent to approximately 2 ppm - agree
4.  10 - 2*2.5 = 5 Gt(C) removed each year - disagree, just because the CO2 is not in the atmosphere, does not mean that it has been removed for the ecosystem, as as per the argument that Mike articulated earlier on the unknown flux of CO2 in the oceans going to the depths. So when CO2 is absorbed by the ocean surface and the biosphere it is primarily in short term storage, so there will be a continual interchange between these reservoirs.  
5.  5/10 is not a tiny, “not measurable” fraction of emitted carbon - as per comments above

With regards,
Kevin

Anton Alferness

unread,
Aug 14, 2021, 5:33:21 PM8/14/21
to Kevin Lister, Greg Rau, John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering, olivier...@ipsl.fr, Douglas MacMartin
Kevin - 

When you say that perhaps El Nino events should be prevented, you are referring to SSTA's, yeah?

Kevin Lister

unread,
Aug 15, 2021, 4:10:30 AM8/15/21
to Anton Alferness, Greg Rau, John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering, olivier...@ipsl.fr, Douglas MacMartin, Stephen Salter
Yes,  El Nino events seem to undo the increase in sink strength. I remember Stephen Salter proposing marine cloud brightening as a way of managing sea surface temperatures as a way of stopping El Ninos.

Jim Baird

unread,
Aug 15, 2021, 12:04:56 PM8/15/21
to Kevin Lister, Anton Alferness, Greg Rau, John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering, olivier...@ipsl.fr, Douglas MacMartin, Stephen Salter

The movement of surface heat below the pycnocline with Thermodynamic Geoengineering amplifies the environmental benefit of the 1998–2013 global warming hiatus that followed the strong El Nino of 1998 15 times over, providing 226 years of global warming respite. 

 

Resplandy et al. used the measurements of atmospheric O2 and CO2 levels as the oceans warm and releases these gases as a proxy for global warming.  By this measure, they found between 1991 and 2016 the ocean gained 1.29 ± 0.20  × 1022 joules of heat/yr, which equates to 410 TW.

They determined about 1.11 ± 0.68 per meg (ppm)/yr of these gases was going into the atmosphere with the concentrations of these gases being 1 part O2 to 1.05 parts CO2.

About .56 ppm of CO2 was therefore added to the atmosphere each year over the course of the study. 

The atmospheric CO2 level as of Aug. 7, 2021 was 415.03 ppm and Aug. 7, 2020 it was 413.04 ppm so, the annual accumulation was 2 ppm. Since 1 ppm  CO2 = 7.81 gigatonne (Gt), about 15.6 Gt of the greenhouse gas went into the atmosphere over the year. The 28% due to surface warming amounted to 4.4 Gt/year, which can be reversed by cooling the surface by converting 7..6% of the heat of warming to work that is performed on land and sending the 92.4% into deep water. From where it returns after 226 years and can be recycled.

 

--

You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email to CarbonDioxideRem...@googlegroups.com.

image001.png
image002.png
image003.png

Douglas MacMartin

unread,
Aug 15, 2021, 3:09:13 PM8/15/21
to SALTER Stephen, Kevin Lister, Anton Alferness, Greg Rau, John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering, olivier...@ipsl.fr

As far as I know, I’m the only one who wrote a paper on this?  (Back in 2009… no idea if the analysis stands the test of time or not!)

 

Nonetheless, while entertaining, would seem unlikely to be any significant benefit in the mean carbon uptake to the extent that it is an oscillation, so damping El Nino’s would also likely damp La Nina’s as well.  (Though I could imagine that there might be some reduction in impacts from reducing extreme ENSO events of either sign.)

 

This seems like a pretty faint and distant tangent to the CDR group though.

 

From: SALTER Stephen <S.Sa...@ed.ac.uk>
Sent: Sunday, August 15, 2021 12:10 PM
To: Kevin Lister <kevin.li...@gmail.com>; Anton Alferness <an...@aquaveticlabs.com>
Cc: Greg Rau <gh...@sbcglobal.net>; John Harte <jha...@berkeley.edu>; Mike MacCracken <mmac...@comcast.net>; Robert Tulip <rtuli...@yahoo.com.au>; Carbon Dioxide Removal <carbondiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; olivier...@ipsl.fr; Douglas MacMartin <dgm...@cornell.edu>

Subject: RE: [CDR] Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

Hi All

Kevin mentioned El Niño events.  The pro El Niño community does not have much political clout so writing messages in Morse code in clouds over an event would be a persuasive and popular demonstration.  I did some calculations about the effort required as part of a note on the Schwartz and Slingo analysis of Twomey.  I am not confident about the assumptions I have used and would be grateful if people could suggest others and also comment on their understanding of the word ‘oscillation’.

If anyone acquires a taste I can send similar calculations for hurricanes, Arctic ice, sea-level rise and Australian bush fires. Apologies to people who already have them.

Stephen

 

From: Kevin Lister <kevin.li...@gmail.com>
Sent: Sunday, August 15, 2021 9:10 AM
To: Anton Alferness <an...@aquaveticlabs.com>

Cc: Greg Rau <gh...@sbcglobal.net>; John Harte <jha...@berkeley.edu>; Mike MacCracken <mmac...@comcast.net>; Robert Tulip <rtuli...@yahoo.com.au>; Carbon Dioxide Removal <carbondiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; olivier...@ipsl.fr; Douglas MacMartin <dgm...@cornell.edu>; SALTER Stephen <S.Sa...@ed.ac.uk>
Subject: Re: [CDR] Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

This email was sent to you by someone outside the University.

You should only click on links or attachments if you are certain that the email is genuine and the content is safe.

Yes,  El Nino events seem to undo the increase in sink strength. I remember Stephen Salter proposing marine cloud brightening as a way of managing sea surface temperatures as a way of stopping El Ninos.

 

 

The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th’ ann an Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336.

erl9_4_045111.pdf

Douglas MacMartin

unread,
Aug 15, 2021, 4:18:51 PM8/15/21
to SALTER Stephen, Kevin Lister, Anton Alferness, Greg Rau, John Harte, Mike MacCracken, Robert Tulip, Carbon Dioxide Removal, geoengineering, olivier...@ipsl.fr
Stephen,

A funny thing about oscillatory systems; If I push my daughter on her swing, she moves further in both directions despite only pushing on one side.

Doug


From: SALTER Stephen <S.Sa...@ed.ac.uk>
Sent: Sunday, August 15, 2021 4:09:16 PM
To: Douglas MacMartin <dgm...@cornell.edu>; Kevin Lister <kevin.li...@gmail.com>; Anton Alferness <an...@aquaveticlabs.com>
Cc: Greg Rau <gh...@sbcglobal.net>; John Harte <jha...@berkeley.edu>; Mike MacCracken <mmac...@comcast.net>; Robert Tulip <rtuli...@yahoo.com.au>; Carbon Dioxide Removal <carbondiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; olivier...@ipsl.fr <olivier...@ipsl.fr>

Subject: RE: [CDR] Re: [geo] RE: IPCC AR6 Summary for Policymakers
 

Doug

Only very stupid fleet controllers would send spray vessels to where there was a La Niña. We can choose where and when.

Stephen

 

 

From: Douglas MacMartin <dgm...@cornell.edu>
Sent: Sunday, August 15, 2021 8:09 PM
To: SALTER Stephen <S.Sa...@ed.ac.uk>; Kevin Lister <kevin.li...@gmail.com>; Anton Alferness <an...@aquaveticlabs.com>
Cc: Greg Rau <gh...@sbcglobal.net>; John Harte <jha...@berkeley.edu>; Mike MacCracken <mmac...@comcast.net>; Robert Tulip <rtuli...@yahoo.com.au>; Carbon Dioxide Removal <carbondiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; olivier...@ipsl.fr
Subject: RE: [CDR] Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

This email was sent to you by someone outside the University.

Robert Tulip

unread,
Aug 16, 2021, 4:18:59 AM8/16/21
to John Harte, Carbon Dioxide Removal, geoengineering

Hello John Harte, thanks for your response to my points.  I am particularly interested in future projections of CO2 equivalents. I am just trying to understand the arithmetic of climate change, and am happy to be corrected if my assumptions or facts are wrong. 

 

I wish the IPCC physical science analysis explained the future trajectory of CO2 equivalents in a more informative way.  CO2e is the key climate metric, as the driver of radiative forcing.  If the AR6 report does explain these integrated measures, I have not seen it and would welcome citations.  I am still reading the technical summary, and have not found good explanation of these key issues.

 

The best graph I have seen on the global trajectory for CO2e is from NOAA – at https://gml.noaa.gov/aggi/aggi.fig4.png. It shows a steep rise to the 2020 level of 504 ppm. On the NOAA figures, by my calculation CO2e will hit 600 ppm in 2048 if the emission rate of the last decade continues, and would peak at 562 ppm under a linear reduction to net zero by 2050.  So I think my statement about sitting at 600 ppm by 2050 is a reasonable scenario, given the distinct unlikeliness of a linear path to zero by then, and the risk that even the net zero path will cause further large scale methane emissions. 

 

How long would CO2e then stay around 600 ppm in a world of rapidly falling emissions?  Your point that the disequilibrium between ocean and atmosphere CO2 operates over longer time than a year means the current 5GtC annual sink would only gradually decline, but also that this decline would be at the direct cost of increased ocean acidification.   

 

Further to your important questions about the future concentration of the atmosphere in that new equilibrium and how fast we will approach it, the problems include whether the world can afford a long period around 600 ppm CO2e, in view of the massive destabilising risks of phase shifts into a hothouse, and whether we need to find better ways to store carbon than as ocean acid, in view of the biodiversity collapse that is already causing.  This is why I see large scale ocean based algae production as central to the long term climate solution.

 

It confused me that NOAA says 66% of warming is from CO2, but the current CO2 level of 415 ppm is 82% of its calculation of CO2e at 504 ppm.  I also don’t understand why carbon accounting uses the 100-year metric of 25 x CO2 for methane warming, when the actual effect of methane in the short term is 100 times worse than CO2.  I would like to know how NOAA calculates its figure of methane share of radiative forcing, which it says has declined since 1979 from 23% to 16.3%.

 

I thought you were a bit harsh in saying that “making incorrect statements about current sinks being immeasurably small, and misunderstanding the disequilibrium processes that govern those sinks, is no way to build a believable case for geoengineering.”  I did not make any such assertions.  If these issues were obvious they would be presented clearly in the WG1 report.    

 

The acidity problem, together with the extreme instability of staying at such a high level of radiative forcing, certainly suggests we should not rely on the ocean sink to gradually remove our emissions.  The case for geoengineering is compelling, firstly to prevent the tipping points that will otherwise occur as a result of the fragile nature of our current situation under relentless forcing, and then as the only way to achieve the ongoing stable regulation of the planetary climate that is required to enable human civilization to flourish.

 

Watching the fall of Kabul last night, I was struck by how people had assumed it would hold for weeks or months, but the pressure of a determined attack led the brittle nature of the government to suddenly shatter.  Climate systems like the Greenland Ice Sheet and Siberian permafrost could have similar fragility and face similar sudden phase shifts.

 

From: John Harte <jha...@berkeley.edu>

Sent: Sunday, 15 August 2021 3:17 AM
To: Robert Tulip <rtuli...@yahoo.com.au>

Cc: Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>
Subject: Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

See below in boldface for responses.

 

John Harte

Professor of the Graduate School

Ecosystem Sciences

ERG/ESPM

University of California

Berkeley, CA 94720

 

On Aug 13, 2021, at 10:01 PM, Robert Tulip <rtuli...@yahoo.com.au> wrote:

 

Hi John, your points below raise essential questions about the justification for CDR compared to the main current policy focus on net zero through decarbonisation.

 

My understanding, which may be wrong, is that your point 4, about the 5 Gt(C) now removed each year by natural processes, is not relevant to a future net zero scenario.  

 

The 5 GTC is removed each year mainly because the 10 GTC/y emission increase creates a disequilibrium with the ocean, so most of that extra CO2 is stored as carbonic acid in the sea.  If we stopped adding 10 GTC/y, there would be no forcing for this ongoing increase of ocean acid, and the 5 GTC removal each year would mostly stop as well.  

 

The magnitude of the disequilibrium is marginally increased because of the emitted 10 Gt(C)/y but the oceans are far more out of equilibrium with the atmosphere, and the deep ocean are far more out of equilibrium with the mixed layer than can be attributed solely to this years emissions. 

 

The problem with your argument, as I understand it, is that prior to the emission era the CO2 level was stable at 280 ppm, but your 5 GTC/y natural removal figure implies it should have been falling by 2ppm/y.

 

That fact is compatible with my argument: in equilibrium there is no sink (other than fluctuations). Indeed, if we now zero out emissions, then subsequently, in some number of decades, we will approach sufficiently close to equilibrium that the removal rate will truly be unmeasurably small.  The real questions are:  what is the future concentration of the atmosphere in that new equilibrium and how fast will we approach it?



 

If we get to net zero just by decarbonising, we will sit at 600 ppm CO2e,

 

No.  The oceans today are not in equilibrium with the today’s atmosphere and the oceans in 2050 will not be in equilibrium with 600 ppm.



given the future GHG emissions to 2050.  In this Gedank, without CDR, there would then be nothing to pull that GHG level down to the Holocene norm.  The ongoing 600 ppm equivalent level will cause rapid sea level rise and other ongoing catastrophes.  

 

So the strategy needs to be immediate planetary brightening to slow down extinction and weather extremes, alongside ramping up CDR, rather than putting all the eggs in the decarbonisation basket.  

 

The IPCC just does not see or acknowledge this logic, let alone refute it.  It is a security and psychology crisis produced by the bullying that creates excessive scientific caution.

 

Net zero has to be seen only as a milestone on the path to massive carbon removals, not as an end in itself.  So the main input to achieving net zero has to be CDR, not decarbonisation, to create the momentum and trajectory to continue toward climate stability and repair.  But before that, the world urgently needs SRM as a tourniquet to stop the patient bleeding to death before we reach the CDR operating table.

 

Where my argument would fail is if, before we transition away from fossil fuels, we unleash huge warming-induced carbon feedbacks from tundra soils, clathrates, wildfires, altered ocean circulation, etc. In that circumstance the natural sinks will be totally overwhelmed and maybe CDR/SRM could at least partially stave off catastrophe.  That is why I favor continuing research on those options. 

 

But making incorrect statements about current sinks being immeasurably small, and misunderstanding the  disequilibrium processes that govern those sinks, is no way to build a believable case for geoengineering.  

Kevin Lister

unread,
Aug 19, 2021, 6:24:21 AM8/19/21
to Michael MacCracken, John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
Hi Mike, 

Likewise apologies for taking the time to reply fully to your email. It's taken a bit of time to read through all the material that this thread has generated and to fully understand the figures emerging as they are quite counter intuitive. 

But in summary, it seems to me that your contention about the slow rate of CO2 sequestration in the event of an ice free planet, where the rate of CO2 removal will be given by the Vostok Ice Core data, is the important point, and this backs John's comments about the rate of CO2 removal becoming much diminished once feedbacks kick in.

I have looked further into the differential between the falls and rises in the CO2 annual cycle, using the figures for CO2 falls corrected for emissions of the earlier post (see also Greg's comments) and have extended the data set to take into account the more recent measurements,  So, using these figures, it seems to me that if CO2 emissions were to crash down to zero by 2050 we would see a slight rise in concentrations first, followed by a steady decline taking about 250 years for CO2 to fall to 300ppm, see graph below.

image.png

But.....

Correlation is not causation - despite the surprisingly  high correlation (Pearson's r = 0.83) between CO2 concentration and the annual fall in emissions, it is not provable that it is CO2 concentrations that  are increasing the sink strength. As per the paper that John attached in his previous post, other factors such as ocean and soil fertilisation could be contributing factors, and these also correlate somewhat with CO2 emissions, as the more industrial activity the more of these factors.  Interestingly, the last data points indicate that we may be at the end of this relationship, but it is too early to tell.  We also do not know what the maximum capacity of the sinks are and so we may find that after a certain reduction of CO2, the rate of removal slows. 

However....

Intergovernmental policy is nowhere near to getting to zero carbon in 2050, and instead the debate is to get to net zero carbon, in which case we will simply maintain the existing high levels of CO2

And......

At the current rate of ice loss in the Arctic, we will be ice free long before CO2 lowers sufficiently to have a beneficial cooling effect, and so the oceans will stagnate and the jet streams will collapse, thus likely limiting any prospect of climatically significant removal of CO2 from the atmosphere. Already there are alarming reports of a weakening of the Gulf Stream and release of large scale CO2 and methane from thawing permafrost. 

Thus, this debate becomes important  because.....

It fully connects SRM with CDR. You and I have both made the case to audiences in the past that SRM is important because a hot planet cannot sequester CO2 as efficiently, but I wonder if that debate is now even more starkly pronounced, such that there is a bifurcation point related to ice conditions, such that with a stable climate we have one CO2 removal regime which is capable of allowing CO2 stabilisation and allowing recovery from the damage that we have done, but once this point is passed, we transition a much slower CO2 removal rate that will take hundreds of thousands of years for stable CO2 levels to be reached as per the Vostok ice core measurement.

In which case the urgency to pursue SRM and cool the planet to safe conditions (less than 0.5degC above the preindustrial baseline) is even more urgent. 

Kevin

Bruce Parker

unread,
Aug 19, 2021, 12:21:47 PM8/19/21
to Kevin Lister, Michael MacCracken, John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

Based on the data from the IPCC 1.5°C Report, it looks like there is a linear relationship between cumulative CO2 emissions (2021-2100) and atmospheric CO2 PPM in 2100:

 

2100 CO2 PPM =0.07688972 * Cum CO2 Emissions + 373.41483927

With  2019 total CO2 emissions at about 42 GTCO2/year, cumulative emissions (from getting to 0 in 30 years starting in 2021)  would be about 630 GTCO2 (=42 * 30 / 2).  So atmospheric CO2PPM would be about 422 PPM in 2100. (Note that the emissions pathway for the scenario where cumulative are 629 GTCO2 is pretty close to an emissions pathway that goes linearly to 0 in 2050 –see attached/enclosed graph)

 

(Data from the AR6 models will likely produce a different equation from the one above, but I would think that it would be in the same “ballpark”.)

 

Bruce Parker

 

===============================================================================

Sample Data from the IPCC 1.5°C Report (Link to "IAMC 1.5°C Scenario Explorer and Data hosted by IIASA")

“Processed” 1.5°C Report data is available at http://www.chesdata.com/co2Budget/IPCC1.5ReportData.xlsx.  Note that the average value for CO2 emissions in 2020 is 40.7.

 

Cum Emissions 2021-2100

PPM (2100)

Temperature Increase

 

Model

Scenario

598

413.2552

1.722546

 

MESSAGEix-GLOBIOM 1.0

CD-LINKS_NPi2020_1000

600

417.2993

1.765153

 

REMIND-MAgPIE 1.7-3.0

PEP_2C_full_goodpractice

600

417.5429

1.83084

 

REMIND 1.7

ADVANCE_2030_WB2C

602

419.2383

1.765829

 

REMIND-MAgPIE 1.7-3.0

PEP_2C_full_eff

602

417.4729

1.614934

 

WITCH-GLOBIOM 4.4

CD-LINKS_NPi2020_1000

603

418.1069

1.604144

 

REMIND-MAgPIE 1.7-3.0

SMP_2C_Sust

604

418.6797

1.766463

 

REMIND-MAgPIE 1.7-3.0

PEP_2C_full_netzero

604

421.1068

1.742483

 

REMIND-MAgPIE 1.7-3.0

SMP_2C_early

606

420.3341

1.787686

 

REMIND-MAgPIE 1.7-3.0

CD-LINKS_NPi2020_1000

607

420.1774

1.819205

 

REMIND 1.7

ADVANCE_2020_WB2C

615

416.2567

1.640914

 

POLES ADVANCE

ADVANCE_2030_WB2C

620

417.2573

1.635425

 

POLES ADVANCE

ADVANCE_2020_WB2C

625

421.1594

1.988915

 

MESSAGE V.3

GEA_Mix_2C_AdvNCO2_PartialDelay2020

629

426.0495

1.734651

 

AIM/CGE 2.1

CD-LINKS_NPi2020_1000

640

423.4639

1.682293

 

AIM/CGE 2.1

EMF33_WB2C_full

643

426.8597

1.913531

 

AIM/CGE 2.1

TERL_2D_LowCarbonTransportPolicy

648

419.8737

1.707089

 

POLES CD-LINKS

CD-LINKS_NPi2020_1000

658

424.8256

1.732615

 

AIM/CGE 2.0

ADVANCE_2020_WB2C

666

423.962

1.795894

 

WITCH-GLOBIOM 4.2

ADVANCE_2020_WB2C

667

422.7235

1.81266

 

WITCH-GLOBIOM 4.2

ADVANCE_2030_WB2C

670

429.1657

1.887814

 

IMAGE 3.0.1

SSP4-26

677

430.5626

1.805355

 

REMIND-MAgPIE 1.7-3.0

EMF33_WB2C_none

684

432.4861

2.050717

 

IEA World Energy Model 2017

Faster Transition Scenario

690

418.6461

1.74994

 

MESSAGE-GLOBIOM 1.0

ADVANCE_2030_WB2C

691

429.0719

1.841933

 

IMAGE 3.0.1

ADVANCE_2020_WB2C

694

426.7583

1.891365

 

AIM/CGE 2.0

SSP5-26

 

 

 

Carbon dioxide emissions from fossil fuels and land use change

https://extinctionrebellion.uk/the-truth/the-emergency/part-1/

Emissions Gap Report 2020

Fossil Fuel Emissions:              36 GTCO2 (other sources)

Land Use Change Emissions    6 GTCO2

Total                                           42 GTCO2

 

https://www.unep.org/emissions-gap-report-2020

 

Fossil Fuel Emissions:              36.44 GTCO2 (other sources)

Land Use Change Emissions    6.6  GTCO2

Total                                           43.04 GTCO2

https://www.statista.com/statistics/276629/global-co2-emissions/

image001.png
image002.png
image003.png
image005.jpg
image008.png
image006.jpg

Michael MacCracken

unread,
Aug 19, 2021, 1:37:37 PM8/19/21
to Kevin Lister, John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

Hi Kevin--Somewhere in an earlier IPCC report (and likely surely elsewhere--perhaps in one of Hansen's papers) there is a CO2 decay equation that has a term (I think mostly exponential decay terms) that is based on the time constants for mixing from the atmosphere into each of the other reservoirs, so into the upper ocean, the deep ocean, the sediments and similarly for the terrestrial biosphere. It might be useful to find that equation and then do the type of evaluation you've done for the seasonal cycle (etc.) and then to explore variations in the time constants included that would reflect such effects as slow down of the ocean circulation, changes in ocean pH, etc.

What bothers me in your analysis is thinking one will go back to something preindustrial (so 300 ppm) as fast as you are indicating. Basically the decline occurs as the amount of CO2 not in sediments mixes through multiple different reservoirs and then is very slowly converted into sediments. What the use of fossil fuels has done is to increase the total amount of CO2 circulating through the various exchanging reservoirs and so, as the increased total amount of CO2 is redistributed among all the parts of the system, I don't think it is appropriate to be thinking about the system in terms of a single decay process and I don't think the concentration will get down to the level at which it was when there was a lower total amount distributed among the reservoirs--that would only occur until all of the fossil fuel CO2 increment is taken up into the sediments, etc.--and that will be a very slow process. This is not to say that the system won't get most of the way there over millennia due to the mixing and new equilibrium distribution that would be established, but full recovery is way, way out there.

Mike

Michael MacCracken

unread,
Aug 19, 2021, 4:20:00 PM8/19/21
to Hawkins, David, Kevin Lister, John Harte, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

Hi David--The question is what "significant" means (as a function of time)? So, the pre-industrial atmosphere had of order 600 GtC, there were about 600 GtC is aboveground biomass and perhaps twice that in the ground, and something like 30,000 GtC in the oceans (only several percent of that in the ocean's mixed layer. So, we've added of order 500 GtC from fossil fuels, so the question is how that will eventually redistribute. Of course there is then also the potential that warming will release carbon in permafrost and hydrates (I'm not sure which of the two pools you would put that in) that would need to be redistributed. And then there is the potential for climate change to alter the ratios and transfer rates (slow ocean overturning and perhaps ocean biological sink as well as affect above-ground biomass/ below-ground biomass, conversions, etc.). Lots of complications, although none really matter unless the nations of the world really get to near NetZero.

I recall a 1981 meeting that the new (then) DOE manager Fred Koomanoff of their CO2/climate program convened, and in this meeting he asked about uncertainties in the carbon budget. As I recall, George Woodwell viewed them as large because his calculations were suggesting that the deforestation source was larger or comparable to the fossil fuel source, whereas Wally Broecker, based on his conclusions from ocean chemistry analyses, said they were only 5%. Wally's comment prompted Koomanoff to then ask why the DOE program was spending 90% of its funds on a 5% uncertainty? With emissions at the time increasing a few percent per year, Wally was right that the other terms in the carbon budget would not have much effect if that trend continued--what he omitted to say, however, was that if one headed down toward zero emissions, the uncertainty he would have given would have been much larger, which is why so much was being spent on this part of the budget at that time--and despite all the research since, getting a good handle on what will happen if we rapidly or slowly get to NetZero and start up CDR while at the same time global warming heats up the various carbon pools still poses a challenge. I think we certainly have to be planning with respect to impacts and the need for CDR with the expectation that the perturbation to the CO2 concentration that has been created will remain as an important influence on the Earth's energy budget for quite some time. If for some reasons that are not now clear, the concentration does come back down fairly quickly, we can cheer mightily, but planning based on that optimistic outcome would seem to be quite risky.

Mike

On 8/19/21 2:26 PM, Hawkins, David wrote:

Important point Mike.

On our planet there are  basically two pools of carbon: loosely, the biosphere and the lithosphere.  Exchanges between the sub-pools of the biosphere (air, land, vegetation, water) make up the (comparatively) fast carbon cycle;  exchanges between the lithosphere and the biosphere were, prior to the advent of the fossil fuel age, part of the (very) slow carbon cycle. 

As you note, the equilibrium content of carbon in the atmosphere, as a component of the biosphere, is a function of the total amount of carbon in the biosphere.  Since our use of fossil fuels has transferred an enormous amount of carbon from the lithosphere to the biosphere, the prudent assumption for planning purposes is that once we stop adding carbon and reach a new equilibrium, the equilibrium carbon content of the atmosphere will be significantly higher than pre-industrial levels for a long time (longer than all existing human institutions and developed settlements). 

David

 

From: Geoengineering <geoengi...@googlegroups.com> on behalf of Mike MacCracken <mmac...@comcast.net>


Reply-To: Mike MacCracken <mmac...@comcast.net>
Date: Thursday, August 19, 2021 at 1:37 PM
To: Kevin Lister <kevin.li...@gmail.com>

Cc: John Harte <jha...@berkeley.edu>, Robert Tulip <rtuli...@yahoo.com.au>, Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>, Geoengineering <geoengi...@googlegroups.com>, "gh...@sbcglobal.net" <gh...@sbcglobal.net>
Subject: Re: [CDR] Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

Hi Kevin--Somewhere in an earlier IPCC report (and likely surely elsewhere--perhaps in one of Hansen's papers) there is a CO2 decay equation that has a term (I think mostly exponential decay terms) that is based on the time constants for mixing from the atmosphere into each of the other reservoirs, so into the upper ocean, the deep ocean, the sediments and similarly for the terrestrial biosphere. It might be useful to find that equation and then do the type of evaluation you've done for the seasonal cycle (etc.) and then to explore variations in the time constants included that would reflect such effects as slow down of the ocean circulation, changes in ocean pH, etc.

What bothers me in your analysis is thinking one will go back to something preindustrial (so 300 ppm) as fast as you are indicating. Basically the decline occurs as the amount of CO2 not in sediments mixes through multiple different reservoirs and then is very slowly converted into sediments. What the use of fossil fuels has done is to increase the total amount of CO2 circulating through the various exchanging reservoirs and so, as the increased total amount of CO2 is redistributed among all the parts of the system, I don't think it is appropriate to be thinking about the system in terms of a single decay process and I don't think the concentration will get down to the level at which it was when there was a lower total amount distributed among the reservoirs--that would only occur until all of the fossil fuel CO2 increment is taken up into the sediments, etc.--and that will be a very slow process. This is not to say that the system won't get most of the way there over millennia due to the mixing and new equilibrium distribution that would be established, but full recovery is way, way out there.

Mike

On 8/19/21 6:24 AM, Kevin Lister wrote:

Hi Mike, 

 

Likewise apologies for taking the time to reply fully to your email. It's taken a bit of time to read through all the material that this thread has generated and to fully understand the figures emerging as they are quite counter intuitive. 

 

But in summary, it seems to me that your contention about the slow rate of CO2 sequestration in the event of an ice free planet, where the rate of CO2 removal will be given by the Vostok Ice Core data, is the important point, and this backs John's comments about the rate of CO2 removal becoming much diminished once feedbacks kick in.

 

I have looked further into the differential between the falls and rises in the CO2 annual cycle, using the figures for CO2 falls corrected for emissions of the earlier post (see also Greg's comments) and have extended the data set to take into account the more recent measurements,  So, using these figures, it seems to me that if CO2 emissions were to crash down to zero by 2050 we would see a slight rise in concentrations first, followed by a steady decline taking about 250 years for CO2 to fall to 300ppm, see graph below.

 

 

There are a couple of things that are immediately obvious:

 

  • There is strong correlation between time and annual CO2 removal, with a correlation coefficient of 0.84. thus potentially indicating that the planet is absorbing more CO2 in response to rising atmospheric concentrations.  
  • The high peaks above the trend in 1992 and 2014 coincide with the Mount Pinatubo and Mount Klyichevshoy which I understand was a significant eruption.

 

 

Michael MacCracken

unread,
Aug 19, 2021, 10:29:28 PM8/19/21
to John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

Hi John--I agree that a few ppm per year for a decade would be very quick and important. I was basically thinking a century or two would be quickly.

Best, Mike

On 8/19/21 5:19 PM, John Harte wrote:
Mike, you wrote:”If for some reasons that are not now clear, the concentration does come back down fairly quickly, we can cheer mightily”

How quickly is “fairly  quickly”?

The physics and chemistry of C redistribution between the atmosphere, the mixed layer, and the deep ocean suggest the following: if we zeroed out emissions today, with an atmospheric CO2 concentration of 412 ppm, then a year from now the concentration will be around 410 ppm. In other words the current sink strength of ~ 2 ppm/y will mostly persist during that coming year. And another year later, we can expect to see around 408 ppm.  This won’t keep up, however,  because, the driving force behind the sink, the disequilibrium between atmosphere and the rest of the biosphere, will shrink over time as the atmospheric CO2 level draws down.  And as the Revelle factor informs us, we will not, even in millenia, return to the old quasi-equilibrium (atm. conc. of ~ 280 ppm).  I don’t know whether to call this drawdown “quick” or not, but a couple of ppm every year for even just a decade seems to me to be significant.

All bets are off if huge new sources of C to the atmosphere from massive forest fires, Arctic soil feedbacks, seafloor clathrates and other catastrophic feedbacks from the warming we have already caused, are unleashed. Or if we hugely alter ocean circulation patterns so that mixed-layer ocean mixing with the deep ocean stalls.  I will "cheer mightily” if we escape those catastrophes. I will say "physics works" if the sink continues to operate as I describe above. 

One other caveat to the above: while the largest sink leads to the oceans, the net terrestrial sink is also important and far harder to make projections about.  Particularly with land use practices, as well as climate change, now strongly influencing it.
<image001.png>
 
But.....
 
Correlation is not causation - despite the surprisingly  high correlation (Pearson's r = 0.83) between CO2 concentration and the annual fall in emissions, it is not provable that it is CO2 concentrations that  are increasing the sink strength. As per the paper that John attached in his previous post, other factors such as ocean and soil fertilisation could be contributing factors, and these also correlate somewhat with CO2 emissions, as the more industrial activity the more of these factors.  Interestingly, the last data points indicate that we may be at the end of this relationship, but it is too early to tell.  We also do not know what the maximum capacity of the sinks are and so we may find that after a certain reduction of CO2, the rate of removal slows. 
 
However....
 
Intergovernmental policy is nowhere near to getting to zero carbon in 2050, and instead the debate is to get to net zero carbon, in which case we will simply maintain the existing high levels of CO2
 
And......
 
At the current rate of ice loss in the Arctic, we will be ice free long before CO2 lowers sufficiently to have a beneficial cooling effect, and so the oceans will stagnate and the jet streams will collapse, thus likely limiting any prospect of climatically significant removal of CO2 from the atmosphere. Already there are alarming reports of a weakening of the Gulf Stream and release of large scale CO2 and methane from thawing permafrost. 
 
Thus, this debate becomes important  because.....
 
It fully connects SRM with CDR. You and I have both made the case to audiences in the past that SRM is important because a hot planet cannot sequester CO2 as efficiently, but I wonder if that debate is now even more starkly pronounced, such that there is a bifurcation point related to ice conditions, such that with a stable climate we have one CO2 removal regime which is capable of allowing CO2 stabilisation and allowing recovery from the damage that we have done, but once this point is passed, we transition a much slower CO2 removal rate that will take hundreds of thousands of years for stable CO2 levels to be reached as per the Vostok ice core measurement.
 
In which case the urgency to pursue SRM and cool the planet to safe conditions (less than 0.5degC above the preindustrial baseline) is even more urgent. 
 
Kevin
 
 
 
On Sat, Aug 14, 2021 at 3:07 AM Michael MacCracken <mmac...@comcast.net> wrote:

Hi Kevin--Apologies for delayed response--dealing with improving defense of our home against some increasingly drenching thunderstorms we've been having.

On your first paragraph, because there is much less land, especially in the mid-latitudes, in the Southern Hemisphere, the seasonal cycle of CO2 is quite small--as an example, you can see the concentration variation in Australia athttps://theconversation.com/southern-hemisphere-joins-north-in-breaching-carbon-dioxide-milestone-59260 . I'm not an expert, but quite likely at least a bit of the small variation may be from the variation in the NH being carried into the SH--and time scale for such spread is of order 6 months. So, there is just very little seasonal variation of CO2 in SH as there is just not much land for seasonal variations in vegetation. This said, there is surely some growth going on--likely mostly steady through the year (on average), but it can't be too much as the SH average concentration is only a bit lower than the NH concentration, and this is due to most sources being in the NH and the time constant for mixing to SH (something like 6-12 months).

<image002.png>
 
There are a couple of things that are immediately obvious:
 
  • There is strong correlation between time and annual CO2 removal, with a correlation coefficient of 0.84. thus potentially indicating that the planet is absorbing more CO2 in response to rising atmospheric concentrations.  
  • The high peaks above the trend in 1992 and 2014 coincide with the Mount Pinatubo and Mount Klyichevshoy which I understand was a significant eruption.
 
 
<image003.png>
In the IPCC AR6 Summary for Policymakers published today, see sections D.1.4 to D.1.6 on page 40 where it mentions CDR -https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf

Chris

-- 
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email toCarbonDioxideRem...@googlegroups.com.
-- 
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email toCarbonDioxideRem...@googlegroups.com.
 
-- 
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email togeoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/012c01d78ea2%2457f06f20%2407d14d60%24%40yahoo.com.au.
 
-- 
You received this message because you are subscribed to the Google Groups "geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email togeoengineerin...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAE%3DUiezcG6_KoUsZMQN4jGfV1MA4EEVmmn_L_%2BHjqq3P6bok1g%40mail.gmail.com.
-- 
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email toCarbonDioxideRem...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/CAE%3DUiewCh1Mdi4ndVRqN1GFGNgbRMXQFbsrqrBKTma2da0chZA%40mail.gmail.com.

Anton Alferness

unread,
Aug 19, 2021, 11:17:10 PM8/19/21
to Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
John Harte - 

I appreciate your input, thanks. Economists say predictions are difficult, especially about the future. 

This nonlinear system that humanity is still learning about is obviously exceptionally difficult to predict (#truestory). But I want to ask about your statement of "All bets are off if huge new sources of C to the atmosphere from massive forest fires, Arctic soil feedbacks, etc..."   <- are those not already in play, albeit early stage? Or what constitutes "huge" in your view? And isn't 'huge' best understood in the context of time? Huge can mean a certain volume all at once or an equivalent volume over X number of years, yeah? I ask because one of the things I think all human beings benefit and also suffer from is a tolerance for small change in the near term while in the mid term (human time scale) seem / feel less significant but are not (frogs in pot or me getting fatter than I used to be 10 years ago...). 

The reason this is a point of contention for me (how we collectively, on average, view the likelihood of x, y or z events shaping out as the future unfolds is because governments and the general public (including finance people) take in these "predictions" (quasi-useful as they are) as data points which inform their decision making. And I for one am not interested in watching more scientists continue to underestimate the climate condition and trajectory as a means of escaping "alarmism" labeling or to avoid the pushback from their conservative peers, without inquiry. 

Speaking of tolerance... I appreciate your tolerance of me asking for clarity.

Best,
-Anton  

Anton Alferness

unread,
Aug 20, 2021, 5:08:29 PM8/20/21
to John Harte, Michael MacCracken, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
Got it, thanks John - much appreciated!




On Fri, Aug 20, 2021 at 10:08 AM John Harte <jha...@berkeley.edu> wrote:
That’s a good question.  In this context I take a pragmatic view of the meaning of “huge”.  We are experiencing very damaging forest fires, we are losing the kelp "forests” of the seas, and a warming climate has also caused the release of carbon dioxide and methane from soils to the atmosphere.  Indeed, my 30-year field observations and experiments in the CO Rockies have documented that this soil-carbon-climate feedback is occurring in one kind of ecosystem, but the phenomenon is widespread). So, yes, you are correct; the feedbacks are already kicking in.  

But remember, the consequences of these already-occurring feedbacks are accounted for in the global carbon budget measurements.  Thus the current net carbon sink strength of ~ 5 Gt(C)/y (that’s C, not CO2) already reflects those existing feedback processes.  “Huge” to me means big enough to erase most or all of, or even reverse, the existing substantial sink.  If our current net sink turns into a net source, say of comparable or greater magnitude, then zeroing out fossil fuel use will not suffice to prevent truly catastrophic warming.   

Greg Rau

unread,
Aug 21, 2021, 1:35:52 AM8/21/21
to Anton Alferness, Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
As for how fast air CO2 falls after anthro emissions are turned off, the paper I usually refer to is 
Archer et al 2009 https://www.annualreviews.org/doi/abs/10.1146/annurev.earth.031208.100206:
image.png
And AR5 had some versions of this:
image.png
image.png
AR6 no doubt repeats or updates these. The point is that it takes a long time, say 50-100kyrs, to get back to pre-industrial CO2 levels, 
barring enhanced CDR.
Greg




--
Greg H. Rau, Ph.D.
Senior Research Scientist
Institute of Marine Sciences
Univer. California, Santa Cruz
https://www.researchgate.net/profile/Greg_Rau
Co-founder and manager, the Carbon Dioxide Removal Google group
Co-founder and CTO, Planetary Hydrogen, Inc.
510 582 5578

Tom Goreau

unread,
Aug 21, 2021, 7:04:12 AM8/21/21
to Greg Rau, Anton Alferness, Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

Since the excess CO2 remains for many thousands of years (as expected, because even in a world with no feedbacks or biology, the CO2 pulse takes 1500 years just to circulate through the ocean and back to the atmosphere), why are some people claiming global warming will stop completely when net zero is reached?

 

Thomas J. F. Goreau, PhD
President, Global Coral Reef Alliance

Chief Scientist, Blue Regeneration SL
President, Biorock Technology Inc.

Technical Advisor, Blue Guardians Programme, SIDS DOCK

37 Pleasant Street, Cambridge, MA 02139

gor...@globalcoral.org
www.globalcoral.org
Skype: tomgoreau
Tel: (1) 617-864-4226 (leave message)

 

Books:

Geotherapy: Innovative Methods of Soil Fertility Restoration, Carbon Sequestration, and Reversing CO2 Increase

http://www.crcpress.com/product/isbn/9781466595392

 

Innovative Methods of Marine Ecosystem Restoration

http://www.crcpress.com/product/isbn/9781466557734

 

No one can change the past, everybody can change the future

 

 

 

From: 'Greg Rau' via Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>


Reply-To: Greg Rau <gr...@ucsc.edu>
Date: Saturday, August 21, 2021 at 1:36 AM
To: Anton Alferness <an...@aquaveticlabs.com>

Cc: Michael MacCracken <mmac...@comcast.net>, John Harte <jha...@berkeley.edu>, "Hawkins, David" <dhaw...@nrdc.org>, Kevin Lister <kevin.li...@gmail.com>, Robert Tulip <rtuli...@yahoo.com.au>, Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>, geoengineering <geoengi...@googlegroups.com>, Greg Rau <gh...@sbcglobal.net>
Subject: Re: [CDR] Re: [geo] RE: IPCC AR6 Summary for Policymakers

 

As for how fast air CO2 falls after anthro emissions are turned off, the paper I usually refer to is 

And AR5 had some versions of this:

Govindasamy Bala

unread,
Aug 21, 2021, 7:47:26 AM8/21/21
to Tom Goreau, Greg Rau, Anton Alferness, Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
The warming is nearly linearly proportional to cumulative carbon emissions. This relationship takes into account the fraction of CO2 that remains
in the atmosphere. Thus, if net emissions are zero at some point in time and beyond, the cumulative emissions are zero and consequently, 
the additional warming is zero



--
With Best Wishes,

-------------------------------------------------------------------
G. Bala
Professor
Center for Atmospheric and Oceanic Sciences
Indian Institute of Science
Bangalore - 560 012
India

Tel: +91 80 2293 3428; +91 80 2293 2505
Fax: +91 80 2360 0865; +91 80 2293 3425
Email: gb...@iisc.ac.in; bala.gov@gmail.com
Web:http://dccc.iisc.ac.in/dr_govindasamy_bala_profile.html
-------------------------------------------------------------------

Michael MacCracken

unread,
Aug 21, 2021, 10:54:40 AM8/21/21
to Govindasamy Bala, Tom Goreau, Greg Rau, Anton Alferness, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

I sense that there are two different interpretations being given to "global warming"--

If we do get to Net-Zero, then, more or less near the same time, there will not be any more warming.

This does not mean that the increase in temperature since preindustrial (often also referred to as global warming) will go away, only that it won't get much bigger (well, except for long feedbacks like ice sheets deteriorating, and so one), and will hopefully start to decline.

Pretty clearly great care needs to be very precise in terms and avoid jargon.

Mike MacCracken

Govindasamy Bala

unread,
Aug 21, 2021, 11:10:43 AM8/21/21
to Michael MacCracken, Tom Goreau, Greg Rau, Anton Alferness, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
A good latest reference that shows that the additional warming is little after emissions stop: 
In Chapter 4 of the AR6 report, Fig. 4.39 shows that the zero-emission commitment (ZEC) is close to zero. 
Bala

image.png

Tom Goreau

unread,
Aug 21, 2021, 4:59:49 PM8/21/21
to Charles H. Greene, Greg Rau, Anton Alferness, Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau

Thanks, that’s exactly my point, around 93% of the planetary heat has been absorbed by the Ocean, and that will come back around in a couple thousand years.

 

Thomas J. F. Goreau, PhD
President, Global Coral Reef Alliance

Chief Scientist, Blue Regeneration SL
President, Biorock Technology Inc.

Technical Advisor, Blue Guardians Programme, SIDS DOCK

37 Pleasant Street, Cambridge, MA 02139

gor...@globalcoral.org
www.globalcoral.org
Skype: tomgoreau
Tel: (1) 617-864-4226 (leave message)

 

Books:

Geotherapy: Innovative Methods of Soil Fertility Restoration, Carbon Sequestration, and Reversing CO2 Increase

http://www.crcpress.com/product/isbn/9781466595392

 

Innovative Methods of Marine Ecosystem Restoration

http://www.crcpress.com/product/isbn/9781466557734

 

No one can change the past, everybody can change the future

 

 

 

From: "Charles H. Greene" <ch...@cornell.edu>
Date: Saturday, August 21, 2021 at 3:24 PM
To: Tom Goreau <gor...@globalcoral.org>
Cc: Greg Rau <gr...@ucsc.edu>, Anton Alferness <an...@aquaveticlabs.com>, Michael MacCracken <mmac...@comcast.net>, John Harte <jha...@berkeley.edu>, "Hawkins, David" <dhaw...@nrdc.org>, Kevin Lister <kevin.li...@gmail.com>, Robert Tulip <rtuli...@yahoo.com.au>, Carbon Dioxide Removal <CarbonDiox...@googlegroups.com>, geoengineering <geoengi...@googlegroups.com>, Greg Rau <gh...@sbcglobal.net>
Subject: Re: [CDR] [geo] RE: IPCC AR6 Summary for Policymakers

 

Hi Tom:

 

It’s the heat disequilibrium between the surface ocean and atmosphere at the time we reach net zero that will determine any warming in the pipeline during the coming decades.

 

Chuck Greene

 

Ocean Visions Leadership Team
https://www.oceanvisions.org




<image001.png>

And AR5 had some versions of this:

<image002.png>

<image003.png>

-- 
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.

To unsubscribe from this group and stop receiving emails from it, send an email toCarbonDioxideRem...@googlegroups.com.


 

-- 

Greg H. Rau, Ph.D.

Senior Research Scientist
Institute of Marine Sciences
Univer. California, Santa Cruz
https://www.researchgate.net/profile/Greg_Rau
Co-founder and manager, the Carbon Dioxide Removal Google group
Co-founder and CTO, Planetary Hydrogen, Inc.
510 582 5578

-- 
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.

To unsubscribe from this group and stop receiving emails from it, send an email toCarbonDioxideRem...@googlegroups.com.

-- 
You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group.
To unsubscribe from this group and stop receiving emails from it, send an email to 
CarbonDioxideRem...@googlegroups.com

Anton Alferness

unread,
Aug 22, 2021, 5:43:41 PM8/22/21
to Tom Goreau, Charles H. Greene, Greg Rau, Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
Charles - 

Do you mean that if we reach net zero (pick a date) and we don't have triggered feedback sources outpacing sinks - then the 
time between the date of net zero and the date 1,xxx years later when the heat imbalance equilibrates we will have no additional heat energy being trapped? 

Or do you think that the GHG heat trapping will continue post net zero because we may be pulling down 25Gt while putting up 25Gt (crossfade point) 
and then the natural sinks (if still active in the same way at that time) will be chewing through 2-3ppm annually? 

If we're at 380ppm when we achieve net zero, don't we still have more years of heat trapping and thus increased heat imbalance (not including the 
already absorbed-by-the-ocean heat energy)? 

Isn't ppm the key driver of heat trapping or is the disequilibrium of heat energy driven by other factors? 

Net zero, correct me if I'm wrong, is not the cow bell that once rung begins the of decreasing warming, just the decreasing of ppm, 
because for some double digit number of years we'll still have high ppm post the net zero moment - and each year in that period will produce a heat imbalance. 

The amount of GHG in the atmosphere is the driver of trapping heat energy, right? What am I missing? 

-Anton


Anton Alferness

unread,
Aug 22, 2021, 6:15:52 PM8/22/21
to Tom Goreau, Charles H. Greene, Greg Rau, Michael MacCracken, John Harte, Hawkins, David, Kevin Lister, Robert Tulip, Carbon Dioxide Removal, geoengineering, Greg Rau
Ah, nevermind. I solved my own confusion. I thought there was a lag in the heat intake / radiation equilibrium process. 

So then if a high percentage of the absorbed ocean heat content comes out during a slow reduction from a high ppm state to a lower ppm state, we might have an increase in warming with reducing ppm. 
Reply all
Reply to author
Forward
0 new messages