Hi Herb--And yet Elon Musk et al. shoot big rockets through the stratosphere with an increasing pace, not to mention the sort of ballistic missiles that North Korea and Houtis are firing, etc. This fear of the slippery slope hangs on and on while the lowering cost of renewable energy continues to reverse the original argument.
Mike
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On Mar 18, 2024, at 1:07 PM, Clive Elsworth <Cl...@endorphinsoftware.co.uk> wrote:
I agree with both of you (Alan and Robbin)
Perhaps a trusted messenger might be Sabine Hossenfelder?
In this video Sabine says climate scientists are probably guilty of confirmation bias on equilibrium climate sensitivity: https://youtu.be/uEZ9HFlqzms
In this one she says climate engineering is a bad idea, but it’s probably going to happen anyway because it’s the cheapest solution: https://youtu.be/MZiEcx0F_CM However she only mentions SAI, and a method of removing water vapour from the stratosphere, which would make almost no difference.
She appears unaware of MCB, and the many other proposals listed on the NOAC website.
Does anyone have access to Sabine?
Clive
From: healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com> On Behalf Of Robin Collins
Sent: Monday, March 18, 2024 3:40 PM
To: Alan Kerstein <alan.k...@gmail.com>
Cc: H simmens <hsim...@gmail.com>; Michael MacCracken <mmac...@comcast.net>; Planetary Restoration <planetary-...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; healthy-planet-action-coalition <healthy-planet-...@googlegroups.com>
Subject: Re: [HPAC] Harvard has halted its long-planned atmospheric geoengineering experiment | MIT Technology Review
If we are still asking the question we need to talk to them directly, frankly, to understand. So far everything I’ve read suggests 1. they don’t think human geo-measures will work (even if they are unwilling to test to see) and/or because the human track record is abysmal; 2. they think these measures will divert from decarbonization; 3. They think decarbonization is sufficient.
All these lead to the same point: #3.
That’s the one to focus on.
Robin
On Mon, Mar 18, 2024 at 11:26 AM Alan Kerstein <alan.k...@gmail.com> wrote:
Dear Herb,
Is it plausible that the opponents of DCC are cognizant of the present danger and the urgency of action? Personally I don’t think so. Would opposition soften if they better understood the situation. I think it’s at least possible, perhaps likely.
Before a doctor advises a patient to go through chemotherapy that will almost kill them, the doctor confronts the patient with the prognosis. (Of course, DCC will not do anything like ‘almost kill’ the planet, but that seems to be the mentality out there.) Sorry for repeating myself, but the circumstances call for hammering away at the prognosis until opposition to DCC softens, setting aside advocacy of DCC until then. This must be done by trusted messengers, who are few and far between these days. The needed steps go from scientific luminaries like James Hansen to trusted messengers to the general public and other stakeholders.
That said, I agree about the need for the NGO that you suggest, but it needs to be cagey regarding its public pronouncements.
Regards,
Alan
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Oswald,
It’s fine in theory to say “All we have to do is remove the GHG which cause Global Warming” but few people believe it can be scaled up fast enough to avoid tipping points, worsening climatic effects etc. How do you think it can be done fast enough?
Best wishes
Chris.
From: 'Oswald Petersen' via Healthy Planet Action Coalition (HPAC) <healthy-planet-...@googlegroups.com>
Sent: Thursday, March 21, 2024 2:10 PM
To: 'Robin Collins' <robin.w...@gmail.com>; 'Sev Clarke' <sevc...@icloud.com>
Cc: 'Alan Kerstein' <alan.k...@gmail.com>; 'Clive Elsworth' <Cl...@endorphinsoftware.co.uk>; 'Herb Simmens' <hsim...@gmail.com>; 'Mike MacCracken' <mmac...@comcast.net>; 'Planetary Restoration' <planetary-...@googlegroups.com>; 'geoengineering' <geoengi...@googlegroups.com>; 'healthy-planet-action-coalition' <healthy-planet-...@googlegroups.com>
Subject: AW: [prag] [HPAC] Harvard has halted its long-planned atmospheric geoengineering experiment | MIT Technology Review
Hi Robin,
we do not need SRM. All we have to do is remove the GHG which cause Global Warming. It is safe, natural and much more efficient than SRM (any variety),
Regards
Oswald Petersen
Atmospheric Methane Removal AG
Lärchenstr. 5
CH-8280 Kreuzlingen
Tel: +41-71-6887514
Mob: +49-177-2734245
Von: healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com> Im Auftrag von Robin Collins
Gesendet: Donnerstag, 21. März 2024 14:01
An: Sev Clarke <sevc...@icloud.com>
Cc: Alan Kerstein <alan.k...@gmail.com>; Clive Elsworth <Cl...@endorphinsoftware.co.uk>; Herb Simmens <hsim...@gmail.com>; Mike MacCracken <mmac...@comcast.net>; Planetary Restoration <planetary-...@googlegroups.com>; geoengineering <geoengi...@googlegroups.com>; healthy-planet-action-coalition <healthy-planet-...@googlegroups.com>
Betreff: Re: [prag] [HPAC] Harvard has halted its long-planned atmospheric geoengineering experiment | MIT Technology Review
I think Herb’s question directed at a core of environmentalists is key:
Is there a point when the climate worsens so much more* that you would support the deployment of cooling if shown to be reasonably safe and effective?
*Note: this can mean too late.
I have raised the same question and I think the answer is that unambiguous critics of SRM methods (“anti-human interventionists”) see the question as a trap, and therefore it “shouldn’t” be answered.
The only rational response to the question is, of course: a resounding Yes. But if you acknowledge that possibility, then you must deny the arguments against testing SRM. And you also have to believe (or pretend) that decarbonization-only IS sufficient, on track, and that the evidence is available to show this. If the evidence points in the opposite direction, then — to stick with your ideology — you must deny, refute or hide it. This is why the problem is now ideological and very dangerous if it spreads into governance. (UNEA!)
I agree with Sev that the publication of the paper (and more of them) will be very important (although I disagree with a MCB-only approach.) I wonder if the publication will be blocked?
We need bullet-proof publications to point to, to build the case in public and government circles. We need a breakthrough or two.
Robin
On Mon, Mar 18, 2024 at 6:45 PM Sev Clarke <sevc...@icloud.com> wrote:
Herb,
Grandiose solutions and strategies are appropriate only for those who can command grandiose resources. We do not. Having our DCC paper published in the Oxford Open Climate Change journal would be a good start; and persuading research organisations (following more the community consultative lead of the Great Barrier Reef MCB experiment, rather than that of SCoPEx/SAI) to model, experiment with, and publish the results from, our many proposed climate solutions would give the article both intellectual and possibly public & political support/funding. Many such experiments and modelling do not require international governance and approval if done in the confines of the EEZ waters of one or more nation states. Successful experiments, followed by gated trials, seem to me to provide our best chance of gaining widespread support for further, cautious deployment. Learning by doing should allow us to minimise any adverse effects whilst maximising the net benefit.
Sev
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On Mar 21, 2024, at 12:26 PM, Alan Gadian <alang...@gmail.com> wrote:
On 21 Mar 2024, at 17:09, Clive Elsworth <Cl...@endorphinsoftware.co.uk> wrote:AlanNo need to apologise. Your message needs to be repeated over and over until it sinks in.As to the concern that MCB benefits some and not others, stratocumulus clouds seem to form at least 25% of the time over most of the ocean. See map on p12: https://atmos.uw.edu/~robwood/teaching/535/StratusStratocumulus_Wood_July22.pdfIs that a correct interpretation?That is the basis on which we are proposing the placement of cheap, remotely controllable aerosol dispersal buoys in many ocean areas. That way meteorologists will have maximum control over which areas of ocean to brighten stratocumulus clouds in, and when. That seems to us the best way to produce the most favourable weather patterns. Obviously it’s controversial, but once water vapour takes over as the main warming agent we must hope that good sense will prevail.Buoys can easily produce nano-sized ammonium chloride salt particles by mixing low concentrations of ammonia and HCl gases in the air. It should also be easy to control particle size by varying flowrates and concentrations.Ammonium chloride is a food additive, hygroscopic like NaCl, and is no more toxic than NaCl. Dispersing low concentration ammonia and HCl over remote ocean areas poses essentially no risk to any lifeforms.Do you see any flaws?Clive
Dear Alan et al.--While I agree with the
discussion on the importance of water vapor feedback, I must
disagree with you that SAI will destroy much of the ozone layer.
That does not happen with large volcanic eruptions, so why do
you think that SAI, done thoughtfully, "will destroy much of the
ozone layer"? If we really get mitigation going, including
especially of the short-lived species and our aim is to get back
to under 1 C, we would need to basically increase the global
albedo by about 1% (so the equivalent of about half of a CO2
doubling), which is a good bit less than has happened with large
volcanic injections. There have been a good number of
simulations done, including models with stratospheric ozone
chemistry, and I don't think these show serious effect on ozone
layer and they do push climate back toward the average
conditions when conditions were cooler, so sort of within the
boundaries of typical variability and far
from the conditions without such intervention.
While MCB is interesting, it is going to be a real challenge to do well given the variability of the weather and of the levels of CCN in various locations, etc., plus in creating regional cool spots, there is the potential (even likelihood) that there will be regional effects on the atmospheric circulation, etc. (after all, El Nino and La Nina events that change regional energy balance have clear, but varying, downstream effects on weather, including on precipitation). I'm all for reducing energy uptake by the ocean, which is where 90+% of the trapped heat ends up, but I would expect there to be both beneficial and adverse changes occurring due to the gradients created. It would be interesting to explore this potential by seeking understanding of the effects on circulation and weather that the sulfate aerosol loading, so a mostly regional effect, has had and is having--so when it was concentrated over the eastern US across the Atlantic to Europe during the 20th century and now mostly in south and east Asia--has anyone done such studies (so ensemble set of runs with sulfate layer in and out, etc.)?
As I've made the point elsewhere, it seems to me
the primary global cooling effort would be most readily
implemented with global SAI (and I think the modeling results
suggest that injections in upper mid-latitudes yields the
smoothest latitudinal response) and then focus the MCB efforts
on dealing with the most intractable impacts, such as the very
warm waters contributing to the most intense tropical cyclones,
high latitude temperature amplification, warming ocean waters
contributing to melting of ice shelves and glacial stream faces,
areas that might be facing persistent drought, and so on. I just
think that getting just the right amount of CCN increase in the
changing set of appropriate locations and conditions around the
world will be a very difficult logistical challenge both to
determine and to implement. Thus, my sense is that SAI
complemented by MCB makes the most sense (the interesting
criticism I've heard is that aggressively attacking the enhanced
methane concentration with iron salt aerosols might be an
alternative to SAI as the baseline intervention--I don't yet
know enough about this idea to consider it a viable,
cost-effective alternative).
Best, Mike MacCracken
PS--I would note that in that it is not clear to
me that the increase in water vapor pressure is determined by
the increase in global average temperature rather than by, for
example, the average increase in temperature over the ocean.
Also, the average temperature increase in low latitudes, which
are mostly ocean, is a good bit less than the global average
increase, and much less than the temperature increase in the
Arctic that helps to raise up the global average temperature
increase. And I think what matters in terms of the strength of
the water vapor feedback is the increase in absolute
humidity--so the temperature increase is greatest where the
increase in absolute humidity per degree is the lowest, and
lowest where the increase in absolute humidity per degree is
greatest. Now, these nuances really don't matter as we are
headed to 3 C and even higher, but I'd suggest we do need to
keep them in mind. I'd also note that while the temperature
increase is lowest in low latitudes where most of the additional
trapped energy goes into evaporation, everything that goes up
has to come down and so this has been leading to greater
likelihood of very intense precipitation even though the
temperature increase is not so much.
.Hi Herb,
Alan Gadian is quite right. The Clausius-Clapeyron equation is indisputable! And the capture of radiated heat by water vapour also fully established many decades ago. The argument about avoided overheating has been that increased anthropogenic GHG emissions cause water vapour pressure in the atmosphere to increase as ocean surface temperatures rise, but reversing the process is very different. This result is a very large hysteresis in reversing the temperature rise. Completely eliminating GHG levels is impractical and in any case will not significantly reduce atmospheric temperatures in a reasonable time. Thank you Alan. This is the strongest argument for preparing for large scale MCB.And of course for deep and rapid emissions reduction. Or, at the current rate we are cooked. And James Lovelock would be proved right.
This must be mainstreamed!
Best,
Dave King
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Dear Oswald--For the benefit of others in the discussion, what my follow-ups with you suggested was that the real key to quickly getting the temperature reductions that you are talking about would be iron aerosol injection to bring the methane concentration down to its preindustrial level. As I indicated, I'm not an expert on such chemistry, but the key seems to be having the iron aerosol be the catalyst for this happening and happening quite rapidly for each bit of iron salt aerosol injected (so a thousand or more methane molecules destroyed before the iron aerosol molecule falls or is rained out). That the iron falling out into the ocean might promote some additional CO2 uptake was nice, but not really the key to the short-term drop in temperature. And for longest life of the iron salt aerosol, injecting it into the free troposphere above the boundary layer was the place to put it.
The other aspects of the plan focused on long-term efforts to bring the CO2 down by, for example, ocean fertilization, which is a bit more speculative and, if done with nutrients from land, might well deplete land fertility by sinking a lot of nutrients into the ocean, something that could be avoided if one brought nutrients up from deeper in the ocean by wave pumping of similar renewable approach.
Focusing on the iron salt aerosol component of the
effort that you describe, so there would be the initial efforts
to bring down the CH4 concentration to of order 700 ppb, and
then the need for an ongoing effort to offset the methane
emissions that are coming off each year and sustaining the
present methane concentration that is nearing 2000 ppb. With the
new methane detecting satellite, the expectation is that there
will be a lot of learning about the sources and the potential
for addressing the issue through emissions reductions versus the
need for deploying iron salt aerosols.
Have there been global atmospheric chemistry simulations of the iron aerosol injection proposal that you have made, indicating whether there might be other consequences from the methane reductions? Presumably, location of the injections does not make much difference as atmospheric mixing will tend to pretty quickly fill any hole that is created--is this correct? What sort of testing has been done of iron aerosol injections?
Mike MacCracken
Dear Chris,
well, it’s the same as with SAI, nobody believes that either.
That’s why I keep repeating the message like a mantra. We CAN remove enough CH4 and CO2 to stop GW. Because apparently nobody is willing and able to read the pdfs I attached recently to almost all my emails in this forum (enclosed again) we have now created a website to get the message across.
You can find it here:
With the GeoRestoration Action Plan we can cool the climate within 20 years by 0.5 to 1.0 °C. That’s sufficient to avert the worst scenarios.
If, as you say, nobody believes it, could one of those non-believers please explain why? This would be most interesting for us.
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Hi Alan--It would have been helpful if that paper provided a bit more information. So, they define the boundary of their ozone hole as the area inside the 220 Dobson Unit (DU) boundary--and this is for total column ozone. They then say the effect of this eruption is mainly at the end of the ozone hole and enlarges it, which sort of implies the effect of 12 DU reduction they talk about is in the region where the total column ozone is about 220 DU, so about a 5% reduction in the total ozone column around the edge of the ozone hole at that time. Now, they do talk about 50% reductions, etc., but is at the particular level of the volcanic debris and, as I read it, not in the total column ozone.
Also, I'd note this paper was for an even in 1991, in the 30+ years since then the stratospheric concentrations of chlorofluorocarbons have gone down and so I think the ozone hole has been closing so not as vulnerable when the modeling was done.
Now, this does not mean there should be no concern when large volcanic injections occur--they can have large effects (it is interesting that the paper does not talk about the consequences of the much larger Pinatubo eruption on the ozone hole--perhaps because by the time the aerosol reached that latitude, it was so spread out the effect was less than the effect of a good bit smaller volcanic eruption right at the edge of the ozone hole at just the right season for there to be an effect). The particular volcanic eruption injected roughly as much S all at one time and one place as early SAI would have spread out over the globe and the year, which is I would assume is the reason that the SAI effect on the ozone layer is generally found to be low in the various simulations that have been done.
So, yes, the issue should be looked at, and I
think this has been done and the effect is not considered a
significant issue (e.g., see
https://acp.copernicus.org/articles/22/4557/2022/)
Best, Mike
Dear Andrew,
Re. Geoengineering
Geoengineering, the large-scale manipulation of a specific process central to controlling Earth’s climate for the purpose of obtaining a specific benefit.
Geoengineering | Definitions, Examples, & Technologies | Britannica
Our subject here is clearly a GeoEngineering subject. If you want to make the GeoEngineering group solely a Solar GeoEngineering group, please call it Solar GeoEngineering.
Re. Dispersion
The process we use for dispersion is called sublimation. We use the jet-engine for the purpose. The result is ultra-fine particles under 100 nm. No drone can do this.
Regards
Oswald Petersen
Atmospheric Methane Removal AG
Lärchenstr. 5
CH-8280 Kreuzlingen
Tel: +41-71-6887514
Mob: +49-177-2734245
Von: Andrew Lockley <andrew....@gmail.com>
Gesendet: Freitag, 22. März 2024 08:25
An: Oswald Petersen <oswald....@hispeed.ch>
Cc: Michael MacCracken <mmac...@comcast.net>; healthy-planet-action-coalition <healthy-planet-...@googlegroups.com>
Betreff: Re: AW: [prag] [HPAC] Harvard has halted its long-planned atmospheric geoengineering experiment | MIT Technology Review
Chaps, this is seemingly nothing to do with the geoengineering Google group. Please stop cc us.
The ISA aerosol can be dispersed with small drones for a lot less than 20m. A test project with existing equipment would be around 100k (I've been in supplier discussions for an MCB project) Pls see my recent paper on drones, noting this considers solids. https://iopscience.iop.org/article/10.1088/2515-7620/ad2f71
Your biggest issue is aerosol size. You can't assume high levels of surface reactivity in large aerosols; most of your material is isolated in the centre of the particle. So you need to concentrate on dispersing extraordinarily fine powders or sprays.
I'm also unclear what altitude you need. Surely stratospheric dispersal would avoid particle rain out? There's a lot of methane in the atmosphere - 2000 ppb, ie 6Gt - so you have to inject a great deal of ISA to meaningfully clean it out, even with the high leverage you offer below (roughly 1 Mt for a one off, or 50ktpa for continuous). You'll have much longer aerosol lifetimes in the stratosphere. However, you also need to consider optical effects on SW / LW radiation. Alternatively, you can apply surface coatings to bare rock faces. If water isn't required then the Atacama desert or Antarctic dry valleys would be an option.
Andrew
On Fri, 22 Mar 2024, 06:34 'Oswald Petersen' via Healthy Planet Action Coalition (HPAC), <healthy-planet-...@googlegroups.com> wrote:
Dear Mike,
Thanks!
I completely agree with all you say. We treat benefits from OIF and MCB (the particles are also CCN) as freebies, benefits unknown in their efficiency. Bringing down methane levels alone would actually be sufficient to avert GW spiralling into the nevernever.
So let us concentrate on CH4. As you say, there are a number of variables which influence the efficiency, and all our efforts in the last two years did indeed concentrate on that efficiency. The most important parameters are:
- Height of dispersal point.
- Location of dispersal point
- Time of dispersal e.g. windspeed, weather conditions.
- Size of particles
- Dispersion method
We have recently changed our dispersion technology from high, ocean-based steel-towers to planes. Those planes have jet-engines which we use for the dispersal of FeCl3 particles. Because of their speed and power jets are the best dispersion tool imaginable. Moving the dispersion point guarantees a large air room to be filled, plus, of course, planes are able to adapt their flight altitude to current weather conditions, which makes the model completely scalable. Today I wonder why it took us so long to understand this, but… there you go…
With this dispersion technology we can basically decide ourselves what concentration of ISA we want on the ground. From our expert in toxicology we know that all concentrations below 1 ppm are harmless. Actually FeCl3 is quite harmless, non-toxic, so there is nothing to fear from that side. We work with much higher concentrations in our lab on a daily basis. The only small problem it poses is the fact that in its fluid state it is corrosive, but I am quite rusty anyway 😊
Back to the point: We think that we can keep the particles afloat for 14 days and more, which would give us the needed time to oxidise around 10.000 CH4 molecules per FeCL3 molecule. So that’s fine in theory.
What we really need is modelling. We are desperately looking for some university which can do the modelling. We have great experts here in Switzerland (e.g. Ulrike Lohmann at ETH), but they declined / ignored our letters up to now. Can you help ? Or anybody?
We would love to do a field test but still have to find 20 Million USD somewhere to buy and modify a plane for our needs. However I think this will be doable…
This is, in a nutshell, where we stand today.
Thanks again
Oswald Petersen
Atmospheric Methane Removal AG
Lärchenstr. 5
CH-8280 Kreuzlingen
Tel: +41-71-6887514
Mob: +49-177-2734245
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Andrew
Part of the problem is that some interventions do more than one thing. For example, Iron Salt Aerosol and other Climate Catalyst Aerosols:
So, should posts on this type of intervention be banned from both the CDR and SRM groups, or allowed in both?
Clive
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Hi Andrew,
there is no need to get cross with me, I willingly oblige, that’s easy.
My recommendation remains the same: Call your group something that reflects its content, then you will get a better targeting automatically. If the content is solar geoengineering, name it that way. If that was the case, AMR has no interest in that group, and we can easily forfeit the venue.
BTW methane removal is neither SRM nor CDR… but that’s just a sidekick…
Hi Adrian--Thanks, I was just drawing result from that paper.
Mike
The boundary of the ozone hole is not at 220 DU, it is at 252 DU, as determined by the NASA ER-2 during AAOE in 1987, see M H Proffitt et al, A chemical definition of the boundary of the ozone hole, J. Geophysical. Res. 1989, 94, 11437-11448. The in situ edge measured by the ER-2 coincided with 252 DU contour of the TOMS column observations, as measured from Punta Arenas. There was a statistical average 10 degree latitude mixing zone centered at the edge. The 220 DU was used by the NASA GSFC team analysing the TOMS data; it is unnecessarily tight. The 1994 ASHOE-MAESA mission from Christchurch, NZ, also saw unequivocal evidence of exchange at the edge of the vortex as measured by observed wind speeds, see Q J R Meteorol Soc, 1997,123, 1-69.
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