Want to know how to reverse global warming?

[Metta W Spencer]

Hi, HPAC Friends!

 

I have a list of 45 proposed ways of reversing global warming. How many of them might actually help?

 

I don’t know, but I’d like to.

Would you?

 

It should be easy to get the basics by doing a few hours of study, so I am inviting some friends to get together to discuss the main proposals.

 

I picked twenty of the most familiar suggestions and hope you’ll join me for an hour in five consecutive weeks to appraise them. In the final meeting we’ll write up our consensus and post our conversation as a video on Substack for the benefit of others. 

 

I hope you’ll participate, for free. I’d love to see you again. Whether you intend to register or not, just join me this time on Wednesday, March 25 at 4 pm Toronto (Eastern) time here: https://zoom.us/j/9108970203. (Yes, so soon!)

 

I asked AI to write some pithy summaries to inform our conversations. Attached you’ll find two files to read before our Wednesday meeting. Usually, these homework assignments will take about half an hour before each meeting. 

[Brian Cady]

Hi Metta Spencer, 

I like the idea of reviewing all the methods for how to do what so needs doing.

I've seen wonderful graphs in which each  proposals has a box, with an area related to how much reversal that method can accomplish, and width according to its cost, with height on the graph corresponding to benefit per cost, all sequenced to show how much we can accomplish with a set amount of funding.

I will try to find an example, and am interested in this work.

Brian

-

For more from Brian, please see:
http://hopefulvision.blogspot.com

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Also, I hope you’ll fill out a survey before the first meeting and again after the last one, to learn how the deliberations affect our opinions. The poll is here: https://projectsavetheworld.substack.com/p/opinion-survey-about-climate-solutions

 

To see other details about the Inquiry, here’s a link on Substack which includes a way to register, if you care to do so now: https://projectsavetheworld.substack.com/p/today-join-the-climate-crisis-public. If you miss a meeting, you can watch the video of what you missed, read that homework assignment, and be ready to join us next time.

 

Warmly, 

Metta

Or you can call me at 1-416-789-2294 or email me at mspe...@web.net.

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[Brian Cady]

Here's an example graph using this technique:

https://rmi.org/how-to-save-money-for-all-americans-efficiency/

Brian

-

For more from Brian, please see:
http://hopefulvision.blogspot.com

[John Ure]

Thank you Metta for your two papers. I would like to share with everyone a paper in support of The Proposal for International Climate Finance which specifically argues for an independent International Green Bank (IGB). The idea has been broached before as I am learning and I hope to collaborate with at least one of those advocates during the course of 2026. The paper An International Green Bank can be downloaded here: https://johnure.net/2026/02/13/an-international-green-bank/ 

I would be delighted with feedback

Within the word limits of Linkedin I today also posted this https://www.linkedin.com/feed/update/urn:li:activity:7442068256879902720/?originTrackingId=2c%2FYqy2iRg2i3WfkQ2ojlQ%3D%3D which addresses the WMO warning of the inbalance referred to in your paper.

Best regards

John Ure

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[H simmens]

Hi Metta,

Did you consider using the Project Drawdown analysis of dozens of potential Climate Remedies as a basis for your discussions? 

Here is a link below to the relevant page showing their analysis of a whole range of climate actions many of which are also covered in your list. 

These analyses were developed through intensive and extensive scientific and technical review. 

That said I’m personally dismayed at the superficial and extremely biased analysis they’ve made of solar radiation management. They have embraced every possible argument against it - while making no effort to analyze its benefits. 

(I raised support for SRM to their Executive Director a couple of years ago on social media and was immediately blocked!) 

Herb

Herb Simmens

Author  of A Climate Vocabulary of the Future

“A wonderful achievement, a SciencePoem, an Inspiration, a Prophecy, also hilarious, Dive in and see"

 Kim Stanley Robinson

@herbsimmens

On Mar 24, 2026, at 11:10 AM, John Ure <ure....@gmail.com> wrote:



To view this discussion visit https://groups.google.com/d/msgid/healthy-planet-action-coalition/CADX3Ag4D94vgZQw4DQLYCPQdxTTsdFg8rD%2BZw7e2TryHrqDFLw%40mail.gmail.com.

[Tom Goreau]

The Drawdown study is very useful and quite far reaching, though not complete.

 

However each method is presented by its own proponents, who sometimes have tunnel vision about the virtues of their own pet solution and blinkers about other solutions.

 

So some estimates may be exaggerated, and others underestimated or missing.

 

From: healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com> on behalf of H simmens <hsim...@gmail.com>
Date: Tuesday, March 24, 2026 at 11:32
To: John Ure <ure....@gmail.com>
Cc: Metta W Spencer <mspe...@web.net>, healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com>
Subject: Re: [HPAC] Want to know how to reverse global warming?

Hi Metta,

 

Did you consider using the Project Drawdown analysis of dozens of potential Climate Remedies as a basis for your discussions? 

 

Here is a link below to the relevant page showing their analysis of a whole range of climate actions many of which are also covered in your list. 

 

These analyses were developed through intensive and extensive scientific and technical review. 

 

That said I’m personally dismayed at the superficial and extremely biased analysis they’ve made of solar radiation management. They have embraced every possible argument against it - while making no effort to analyze its benefits. 

 

(I raised support for SRM to their Executive Director a couple of years ago on social media and was immediately blocked!) 

 

Drawdown® Explorer drawdown.org

 

To view this discussion visit https://groups.google.com/d/msgid/healthy-planet-action-coalition/3719EAE8-96D0-46A6-9EE8-EAB5EF5B2A02%40gmail.com.

[Brian Cady]

I've found a better example of this type of graph, called a Marimekko chart, by using perplexity.ai, which states:

"You're thinking of a Marginal Abatement Cost Curve (MACC)—also called a cost supply curve or Marimekko chart with variable-width bars. RMI has used these extensively in energy and climate reports.

What It Shows

Marginal Abatement Cost Curve

Each box/bar represents a solution or measure, with:

• Height = cost per unit of result (e.g., $/ton CO₂ reduced, ¢/kWh saved)

• Width = total potential impact (e.g., tons of CO₂ abated, kWh saved)

• Area = total cost (or savings) of implementing that solution

• Left-to-right order = cheapest/most cost-effective → most expensive

Boxes below the zero line actually save money (negative cost); those above cost money."

Brian

-

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[John Dixon]

Tom may be correct.  It would be great to do a systematic update.

 

Another interesting aspect was that it included serious consideration of nature based/biological solutions whereas recent narratives have shifted towards engineering solutions.

 

I wished I would have had the time to disaggregate the value/impacts by the major land use systems of the world, because the values and impacts of the options play our quite differently for populations in coastal/maritime regions to mountain ranges to deserts.

 

John

To view this discussion visit https://groups.google.com/d/msgid/healthy-planet-action-coalition/SA1PR13MB5005CDD4FC79FF3A47B2B9A6DD48A%40SA1PR13MB5005.namprd13.prod.outlook.com.

[Metta W Spencer]

Not tomorrow.  Today!

M

On Mar 24, 2026, at 11:37 AM, Tom Goreau <gor...@globalcoral.org> wrote:

The Drawdown study is very useful and quite far reaching, though not complete.

 

However each method is presented by its own proponents, who sometimes have tunnel vision about the virtues of their own pet solution and blinkers about other solutions.

 

So some estimates may be exaggerated, and others underestimated or missing.

 

From: healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com> on behalf of H simmens <hsim...@gmail.com>
Date: Tuesday, March 24, 2026 at 11:32
To: John Ure <ure....@gmail.com>
Cc: Metta W Spencer <mspe...@web.net>, healthy-planet-...@googlegroups.com <healthy-planet-...@googlegroups.com>
Subject: Re: [HPAC] Want to know how to reverse global warming?

Hi Metta,

 

Did you consider using the Project Drawdown analysis of dozens of potential Climate Remedies as a basis for your discussions? 

 

Here is a link below to the relevant page showing their analysis of a whole range of climate actions many of which are also covered in your list. 

 

These analyses were developed through intensive and extensive scientific and technical review. 

 

That said I’m personally dismayed at the superficial and extremely biased analysis they’ve made of solar radiation management. They have embraced every possible argument against it - while making no effort to analyze its benefits. 

 

(I raised support for SRM to their Executive Director a couple of years ago on social media and was immediately blocked!) 

 

<DrawdownExplorer_TitleCard_1200x630_01_0.jpg>

Drawdown® Explorer drawdown.org

 

[Ron Baiman]

Thank you Metta! 

If this would be of interest, I'd be glad to discuss the 4-8 methods that could likely or potentially provide significant near-term cooling in our "Open Letter in Support of Applied-Science Testing and Piloting of Near-term Global Climate Cooling Approaches" submitted to Oxford Open Climate Change, and currently under review , see table 1 on p. 12 here:

https://docs.google.com/document/d/1-ylFDVmw362TQmKxmmH1_NTlw7k-RHMS/edit?usp=sharing&ouid=116465941111195452408&rtpof=true&sd=true

Best,

Ron

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Also, I hope you’ll fill out a survey before the first meeting and again after the last one, to learn how the deliberations affect our opinions. The poll is here: https://projectsavetheworld.substack.com/p/opinion-survey-about-climate-solutions

 

To see other details about the Inquiry, here’s a link on Substack which includes a way to register, if you care to do so now: https://projectsavetheworld.substack.com/p/today-join-the-climate-crisis-public. If you miss a meeting, you can watch the video of what you missed, read that homework assignment, and be ready to join us next time.

 

Warmly, 

Metta

Or you can call me at 1-416-789-2294 or email me at mspe...@web.net.

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[John Nissen]

Hi Brian,

This graph is all about the CO2 side of things, which can slow global warming but not reverse it.  Only SRM has a chance to lower global temperatures. To reverse climate change, refreezing the Arctic is a priority above global cooling. And only SAI has the cooling power to refreeze the Arctic. 

Cheers John 

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