RE: PRAG meeting and SLR: Satellite images reveal dramatic loss of global wetlands over past two decades

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SALTER Stephen

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Jun 16, 2022, 5:46:02 AM6/16/22
to John Nissen, Planetary Restoration, Shaun Fitzgerald, geoengi...@googlegroups.com

Hi All

John Nissen writes below that marine cloud brightening is not so scalable as cloud coverage is limited.

Below is a table from Jones Haywood and Boucher of the UK  Hadley Centre in the Journal of Geophysical Research 2009 showing 0.97 watts per square metre of cooling, about half the warming problem, could come from treating just 3.3% of the earth’s surface. This used the same spray regions all the year round but vessel mobility would allow us to track the movement of the best regions.

 

 

Charlson and Lovelock in Nature 326 pp 655-661, 1987 say that low but not high-level clouds cover 18% of the oceans.

I have sent some of you the attached calculations about sea level rise and would be grateful if you could suggest other input assumptions. Marine cloud brightening has the advantage of regional and seasonal control with high-frequency and low phase-lag.

 

Stephen

 

 

From: planetary-...@googlegroups.com <planetary-...@googlegroups.com> On Behalf Of John Nissen
Sent: Thursday, June 16, 2022 2:04 AM
To: Planetary Restoration <planetary-...@googlegroups.com>; Shaun Fitzgerald <sd...@cam.ac.uk>
Subject: PRAG meeting and SLR: Satellite images reveal dramatic loss of global wetlands over past two decades

 

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 Hi everyone, 

 

I'm in Canada for the next week without access to zoom so next Monday's meeting is cancelled.

 

I've had a chance to do a lot of reading and this paper (1) mentions the huge impact of sea level rise:

 

More than 1 billion people now live in low-elevation coastal areas globally.

 

The Greenland Ice Sheet could give us a sudden SLR of half a metre or more if glacier avalanches are triggered by dammed internal lake collapse or earthquake. To reduce this risk and the risk from growing extremes of weather/climate the Arctic must be cooled as quickly as possible.

 

Powerful intervention is mandatory. Stratospheric Aerosol Injection north of 50N is our best bet. It would be wonderful if the CCRC could endorse this strategy while SAI still has a good chance of success. Urgency cannot be overstated. 

 

(MCB is not so scalable as cloud to brighten is limited.  Using both SAI and MCB might be ideal, if MCB can be deployed quickly enough at strength.  SAI has an advantage of the blanket cooling while MCB might provide more specific cooling where it helps.)

 

We need a campaign to recognise that SAI can be deployed extremely safely, mimicking a high latitude volcano such that ozone hole is not significantly affected and winter warming avoided. 

 

The solution to the immediate climate emergency is so simple yet so far from being accepted let alone implemented - it's crazy.

 

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Sea level rise 5.pdf

Renaud de RICHTER

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Jun 16, 2022, 9:22:09 AM6/16/22
to Stephen Salter, John Nissen, Planetary Restoration, Shaun Fitzgerald, geoengi...@googlegroups.com
Don't forget also Ahlm, L., Jones, A., Stjern, C. W., Muri, H., Kravitz, B., & Kristjánsson, J. E. (2017). Marine cloud brightening–as effective without clouds. Atmospheric Chemistry and Physics, 17(21), 13071-13087.  https://acp.copernicus.org/articles/17/13071/2017/

Sulfates from ships (and from fossil fuels power plants) are also effective without clouds!

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SALTER Stephen

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Jun 16, 2022, 10:07:37 AM6/16/22
to Renaud de RICHTER, John Nissen, Planetary Restoration, Shaun Fitzgerald, geoengi...@googlegroups.com

Renaud

I think that the reason for good cooling from spray under clear skies is that they were taking a long term average and spray under clear skies has longer to spread and a longer life.  Double the drop number means a bit over 5% more reflectivity.   Because of this log term in Twomey we want the low dose over a wide area that we get if we spray under clear skies.  It is even better if we spray just after rain which has cleaned the air which will eventually get to somewhere with a high enough relative humidity. We are not in a hurry.

Stephen

Oeste

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Jun 16, 2022, 10:29:12 AM6/16/22
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Hi Renaud

Many thanks for this paper. It gives us references that also ISA probably produces this direct aerosol effect. Probably a little bit less because of the yellow-white ISA coloration. Within low humidity dry environments where no condensation can occure the ISA particles are also in a shrunk condition hence its color becomes lighter than in the expanded conditions at high humidity.

Franz

Alan Gadian

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Jun 16, 2022, 10:43:59 AM6/16/22
to Stephen Salter, Renaud de RICHTER, John Nissen, Planetary Restoration, Shaun D Fitzgerald, geoengi...@googlegroups.com
Dear Renaud and Stephen,

Truth often gets lost in the story.  If you believe the climate models (which I have concerns about),  but are the basis of the ICCP6 results, the simulations of MCB can easily provide 4W/m^2 cooling with < 10% of the clouds, (only the stratocumulus).  If you seed more, you can induce an ice age, so says the climate models.  If you look at the cloud models for small scale regions (resolution 20m which I strongly believe are correct), the increases in the albedo match the climate model values.  There are side effects for all  interventions.  Please don’t ignore the fact that we use NWP rather models everyday and they do work.   Stratospheric Sulphur has been shown to work, with other very significant side effects and inability to switch off.  The aerosol would reach polar stratosphuric regions within ~ 4 weeks.  

The weather is global.  The atmosphere’s role is solely to take heat from the equator to the pole.  With just MCB seeding any one of the three main sub-tropical stratocumulus cloud decks would affect the WHOLE planet, not just a region.  The biggest signal would be in the polar regions. This is often forgotten when discussing climate.  With a reduced AMOC, Western Europe will cool, but the ramifications around the globe are huge.

My personal view that a combination of measures may well be required; relying on one seems foolhardy as each has limitations. The consequences of MCB are global and one has to understand planetary meteorology to appreciate this.  

The CCRA3 report (June 2021) is a far better assessment (in my opinion) than the IPPC6 WG1 report (July 2021)which is “concensusly” bland. The draft ONR document for the UK  https://www.onr.org.uk/consultations/2021/external-hazards/ns-tast-gd-013-annex-3.pdf is a far more accurate assessment in my opinion and makes stark reading - but then I would say that as I was a co-author . Ukraine has shown that world leaders are incapable of realising the consequence of their actions. One suspects climate change is not on the radar at all, but being ready when is does hot will be significant. 

Alan
 
Alan Gadian



On 16 Jun 2022, at 15:07, SALTER Stephen <S.Sa...@ed.ac.uk> wrote:

Renaud
I think that the reason for good cooling from spray under clear skies is that they were taking a long term average and spray under clear skies has longer to spread and a longer life.  Double the drop number means a bit over 5% more reflectivity.   Because of this log term in Twomey we want the low dose over a wide area that we get if we spray under clear skies.  It is even better if we spray just after rain which has cleaned the air which will eventually get to somewhere with a high enough relative humidity. We are not in a hurry.
Stephen
 
 
From: Renaud de RICHTER <renaud.d...@gmail.com> 
Sent: Thursday, June 16, 2022 2:22 PM
To: SALTER Stephen <S.Sa...@ed.ac.uk>
Cc: John Nissen <johnnis...@gmail.com>; Planetary Restoration <planetary-...@googlegroups.com>; Shaun Fitzgerald <sd...@cam.ac.uk>; geoengi...@googlegroups.com
Subject: Re: [geo] RE: PRAG meeting and SLR: Satellite images reveal dramatic loss of global wetlands over past two decades
 
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.
Don't forget also Ahlm, L., Jones, A., Stjern, C. W., Muri, H., Kravitz, B., & Kristjánsson, J. E. (2017). Marine cloud brightening–as effective without clouds. Atmospheric Chemistry and Physics, 17(21), 13071-13087.  https://acp.copernicus.org/articles/17/13071/2017/
 
Sulfates from ships (and from fossil fuels power plants) are also effective without clouds!
 
Le jeu. 16 juin 2022 à 11:46, SALTER Stephen <S.Sa...@ed.ac.uk> a écrit :
Hi All
John Nissen writes below that marine cloud brightening is not so scalable as cloud coverage is limited.
Below is a table from Jones Haywood and Boucher of the UK  Hadley Centre in the Journal of Geophysical Research 2009 showing 0.97 watts per square metre of cooling, about half the warming problem, could come from treating just 3.3% of the earth’s surface. This used the same spray regions all the year round but vessel mobility would allow us to track the movement of the best regions.
 
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Veli Albert Kallio

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Jun 16, 2022, 1:34:42 PM6/16/22
to Stephen Salter, alang...@gmail.com, Renaud de RICHTER, John Nissen, Planetary Restoration, Shaun D Fitzgerald, geoengi...@googlegroups.com
Hi Alan,

Did you say it seriously, that we could induce a new ice age.

I simply do not believe that. I think models are skewed for too little rather than too much considering long term background forcings already in place (as CO2 stays in air for circa 1000 years).

New Scientists just published yesterday a pretty damning graphics showing it almost impossible to stay within +1.5C rise.

Albert

From: geoengi...@googlegroups.com <geoengi...@googlegroups.com> on behalf of Alan Gadian <alang...@gmail.com>
Sent: 16 June 2022 15:43
To: Stephen Salter <s.sa...@ed.ac.uk>
Cc: Renaud de RICHTER <renaud.d...@gmail.com>; John Nissen <johnnis...@gmail.com>; Planetary Restoration <planetary-...@googlegroups.com>; Shaun D Fitzgerald <sd...@cam.ac.uk>; geoengi...@googlegroups.com <geoengi...@googlegroups.com>
Subject: Re: [geo] PRAG meeting and SLR: Satellite images reveal dramatic loss of global wetlands over past two decades
 

Alan Gadian

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Jun 16, 2022, 2:16:16 PM6/16/22
to Veli Albert Kallio, Stephen Salter, Renaud de RICHTER, John Nissen, Planetary Restoration, Shaun D Fitzgerald, geoengi...@googlegroups.com
Dear Veli,

Ummm.  If you seeded the whole oceans in the subtopics, then the paper ( Latham 2008 i think) shows the model predicts up to 10% increase in  albedo.  Seeding in storm tracks is totally irrelevant. I am not sure i agree with the magnitude 10% but  that is what Hadgem produced. Cloud albedo is a critical factor.  The hadgem climate model used to have a twin ICTZ .  when albedo was changed ( Haywood et al.) for the namibia cloud deck , a single ICTZ, as reality , was produced. 

So Parkes paper on meridional heat transfer and the original Latham papers give 1/2 a petawatt difference in polar heat flow.  The oceans don’t react quickly ( my theory) and the warmer sub article waters radiate to space so the model suggests ( if you believe it) quite a rapid response - decades . 

So yes , the model bright the ice down to iceland plus! 

We are well past 1.5C in extremes, and pretty convinced by earlier 2050 if not 2035, ice free North pole in September ( < 15 % broken ice) .   Totally impossible and expecting 3C by 2080 

cheers 
Alan 


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Alan Gadian, UK.
Tel: +44 / 0  775 451 9009 
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On 16 Jun 2022, at 18:33, Veli Albert Kallio <albert...@hotmail.com> wrote:


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