> Dear Colleagues, > > Thank you again to all who have signed! > > *We now have 30 signatures and just need 12 more to achieve our goal of 42* > (see p. 7): > https://docs.google.com/document/d/1-ylFDVmw362TQmKxmmH1_NTlw7k-RHMS/edit?usp=sharing&ouid=116465941111195452408&rtpof=true&sd=true > > Please consider signing if you haven't yet! The sooner we get to our goal > the sooner this will be submitted and (hopefully) published. > > Best, > Ron and Mike > > On Mon, Feb 16, 2026 at 5:14 PM Ron Baiman <[email protected]> wrote: > >> Dear Colleagues, >> >> I've been encouraged to send out this motivational blurb and invitation >> to sign the HPAC "Open Letter in Support of Applied-Science Testing and >> Piloting of Near-term Global Climate Cooling Approaches" again. >> >> Our goal is 42 signatures (to match Siegert et al. 2025) and we currently >> have 15 (see p. 7 of letter), so need 27 more. >> >> Thank you! >> >> Best, >> Ron >> >> >> >> >> >> ---------- Forwarded message --------- >> From: Ron Baiman <[email protected]> >> Date: Tue, Feb 10, 2026 at 12:41 PM >> Subject: Invitation to co-sign an open letter supporting applied-science >> testing and piloting of near-term global climate cooling >> >> Dear Colleagues, >> >> >> >> We invite you to join us in signing this: Open Letter in Support of >> Applied-Science Testing and Piloting of Near-term Global Climate Cooling >> Approaches: ( >> https://docs.google.com/document/d/1-ylFDVmw362TQmKxmmH1_NTlw7k-RHMS/edit?usp=sharing&ouid=116465941111195452408&rtpof=true&sd=true) >> in >> which we stress that if we're going to start "shaving the peak" in >> 2030-2050, as many global climate model geoengineering simulations assume, >> *we >> need to start working on this now,* *or, at least, as soon as possible* >> . >> >> >> >> As many of you know we have been working on this letter for many months. >> During this time it has undergone numerous revisions in response to >> extensive feedback from numerous colleagues - some among the current >> signatories and some not. We believe at this point that further editing has >> reached a point of diminishing returns and that it is time to move forward >> on garnering further support in advance of (hopeful) publication. >> >> >> >> We think that this letter could be an important component of the >> political effort to open the Overton Window that we and our near allies >> have expanded to include general support for geoengineering "research," but >> that continues to be firmly shut on the issue of "piloting." The following >> quote, for example, is from the September 2023 Executive Summary of the >> Climate Overshoot Commission ( >> https://www.overshootcommission.org/_files/ugd/0c3b70_bab3b3c1cd394745b387a594c9a68e2b.pdf >> ): >> >> "Countries should adopt a moratorium on the deployment of solar radiation >> modification and large-scale outdoor experiments that would carry risk of >> significant transboundary harm, while expanding research, and pursuing >> international governance dialogues." >> >> >> >> We disagree with this formulation as it appears to fail to take into >> account the ever larger catastrophic climate events that will happen if >> cooling efforts are not initiated in the very near future. Both "large >> outdoor" applied-science testing and piloting of near-term global >> climate cooling approaches need to start now in order to be implemented in >> the 2030s at the latest. >> >> >> >> Most of you are likely familiar with the general HPAC position in favor >> of urgent climate cooling being implemented as a complementary approach to >> more aggressive efforts to cut emissions of CO2 and CH4, increase >> resilience, and initiate efforts to build up Carbon Dioxide Removal.. We >> believe that our open letter sharpens our call for a credible comprehensive >> approach to controlling climate change and clarifies the practical >> implications of the need for adding urgent near-term global cooling to the >> active set of policy options. >> >> >> >> With the global temperature increase poised to speed past the >> aspirational goal of the Paris Accord, we are asking for your signature in >> support of countering voices that see efforts to augment and complement >> emissions reduction with carefully research cooling influences as more >> risky than continuing toward projected global warming of 2 to even 3°C or >> more of global warming, as argued, for example, in Siegert et al. (2025), >> who asserted that >> >> "… further research into these [geoengineering] techniques would not be >> an effective use of limited time and resources.” [brackets ours]. >> >> >> >> Finally, this letter is part of a parallel effort by HPAC’s Steering >> Circle to transmit a position paper with a similar message to IPCC >> delegations in advance of COP-31, for which, needless to say, broad support >> for this letter would be helpful. >> >> >> >> We encourage you to consider co-signing this letter if you agree with the >> need to augment COP’s mitigation-focused approach that, while essential to >> reduce peak warming, is proving insufficient to meet the goals of the Paris >> Accord, much less pull the world back from likely exceeding an increasing >> number of irreversible tipping points. >> >> >> >> To indicate your concurrence, please send a note to Ron Baiman at >> *[email protected] >> <[email protected]>* (also copying Michael MacCracken at >> [email protected]). Please include your name as you would like it to >> appear and your affiliation(s), including other affiliations than just >> HPAC. >> >> >> >> Thank you, >> >> >> >> Best, >> >> Ron and Mike >> >> >> >> For the Co-Signers >> >> >> -- >> Healthy Planet Action Coalition <http://www.healthyplanetaction.org> >> YouTube Channel >> <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> >> @HPACoalition (Bluesky and Twitter/X) >> SAI Deployment and Risks to Human Civilization: The Question is No Longer >> If, but How, When, Where, and by Whom? >> <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> >> 2025 Baiman, MacCracken and Slater. AGU Poster >> On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: >> What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> >> Addressing the Urgent Need for Direct Climate Cooling: Rationale and >> Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> >> Baiman et al. 2024. *Oxford Open Climate Change* >> An Open Letter to the IMO Supporting Maritime Transport that Cools the >> Atmosphere While Preserving Air Quality Benefits >> <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et >> al. 2024. *Oxford Open Climate Change* >> >> >> -- >> Healthy Planet Action Coalition <http://www.healthyplanetaction.org> >> YouTube Channel >> <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> >> @HPACoalition (Bluesky and Twitter/X) >> SAI Deployment and Risks to Human Civilization: The Question is No Longer >> If, but How, When, Where, and by Whom? >> <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> >> 2025 Baiman, MacCracken and Slater. AGU Poster >> On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: >> What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> >> Addressing the Urgent Need for Direct Climate Cooling: Rationale and >> Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> >> Baiman et al. 2024. *Oxford Open Climate Change* >> An Open Letter to the IMO Supporting Maritime Transport that Cools the >> Atmosphere While Preserving Air Quality Benefits >> <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et >> al. 2024. *Oxford Open Climate Change* >> > > > -- > Healthy Planet Action Coalition <http://www.healthyplanetaction.org> > YouTube Channel <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> > @HPACoalition (Bluesky and Twitter/X) > SAI Deployment and Risks to Human Civilization: The Question is No Longer > If, but How, When, Where, and by Whom? > <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> > 2025 Baiman, MacCracken and Slater. AGU Poster > On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: > What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> > Addressing the Urgent Need for Direct Climate Cooling: Rationale and > Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> > Baiman et al. 2024. *Oxford Open Climate Change* > An Open Letter to the IMO Supporting Maritime Transport that Cools the > Atmosphere While Preserving Air Quality Benefits > <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et > al. 2024. *Oxford Open Climate Change* >
-- Healthy Planet Action Coalition <http://www.healthyplanetaction.org> YouTube Channel <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> @HPACoalition (Bluesky and Twitter/X) SAI Deployment and Risks to Human Civilization: The Question is No Longer If, but How, When, Where, and by Whom? <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> 2025 Baiman, MacCracken and Slater. AGU Poster On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> Addressing the Urgent Need for Direct Climate Cooling: Rationale and Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> Baiman et al. 2024. *Oxford Open Climate Change* An Open Letter to the IMO Supporting Maritime Transport that Cools the Atmosphere While Preserving Air Quality Benefits <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et al. 2024. *Oxford Open Climate Change* -- Healthy Planet Action Coalition <http://www.healthyplanetaction.org> YouTube Channel <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> @HPACoalition (Bluesky and Twitter/X) SAI Deployment and Risks to Human Civilization: The Question is No Longer If, but How, When, Where, and by Whom? <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> 2025 Baiman, MacCracken and Slater. AGU Poster On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> Addressing the Urgent Need for Direct Climate Cooling: Rationale and Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> Baiman et al. 2024. *Oxford Open Climate Change* An Open Letter to the IMO Supporting Maritime Transport that Cools the Atmosphere While Preserving Air Quality Benefits <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et al. 2024. *Oxford Open Climate Change* -- Healthy Planet Action Coalition <http://www.healthyplanetaction.org> YouTube Channel <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> @HPACoalition (Bluesky and Twitter/X) SAI Deployment and Risks to Human Civilization: The Question is No Longer If, but How, When, Where, and by Whom? <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> 2025 Baiman, MacCracken and Slater. AGU Poster On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> Addressing the Urgent Need for Direct Climate Cooling: Rationale and Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> Baiman et al. 2024. *Oxford Open Climate Change* An Open Letter to the IMO Supporting Maritime Transport that Cools the Atmosphere While Preserving Air Quality Benefits <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et al. 2024. *Oxford Open Climate Change* -- Healthy Planet Action Coalition <http://www.healthyplanetaction.org> YouTube Channel <https://www.youtube.com/channel/UCdt5vatByfyg-Pm9Vu6ahZg> @HPACoalition (Bluesky and Twitter/X) SAI Deployment and Risks to Human Civilization: The Question is No Longer If, but How, When, Where, and by Whom? <https://drive.google.com/file/d/1hvklktEZSciny9JnuMaU4Jn6_2pRN8w6/view?usp=sharing> 2025 Baiman, MacCracken and Slater. AGU Poster On-line Conference_The Global Heating Emergency:_Preventing 2.0C by 2040: What's the Plan? <https://www.youtube.com/watch?v=AmAnfVCGVeI> Addressing the Urgent Need for Direct Climate Cooling: Rationale and Options <https://academic.oup.com/oocc/article/4/1/kgae014/7731760> Baiman et al. 2024. *Oxford Open Climate Change* An Open Letter to the IMO Supporting Maritime Transport that Cools the Atmosphere While Preserving Air Quality Benefits <https://academic.oup.com/oocc/article/4/1/kgae008/7706251>. Baiman et al. 2024. *Oxford Open Climate Change* -- 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 [email protected]. To view this discussion visit https://groups.google.com/d/msgid/geoengineering/CAPhUB9BRKtjyBoP9TQRG5pxF83dKWNQ3T7%3DX5oLMgwMVLrM_mg%40mail.gmail.com.
