After the Mount Pinatubo volcano erupted in 1991, the earth cooled by half a degree Celsius for the next two years.

Should we do something similar, now, on purpose?

The Story in Four Minutes

Nina Grant, Solar Geo Society Ambassador,
PhD Candidate, Rutgers University

There are over a trillion tons of excess CO2 in the atmosphere, and the CDR industry aims to remove a grand total of a billion of those tons over the entire course of the next twenty years. Nina Grant speaks about the implications.

After the Mount Pinatubo volcano erupted in 1991, the earth cooled by half a degree Celsius for the next two years.

Should we do something similar, now, on purpose?

The Story in Four Minutes

Nina Grant, Solar Geo Society Ambassador,
PhD Candidate, Rutgers University

Our Mission:

Solar geo offers hope that we might cool the planet. Understanding the concept simply requires thinking about the difference between trillions, billions, and millions.

There will always be disagreements over the concept of solar geo (short for solar geoengineering). Our mission is for those disagreements to be better grounded in math and science.

The Five-Minute Counterargument

Raymond Pierrehumbert

Physics Professor
Oxford University

Perhaps the world’s most vocal academic physicist criticizing solar geo

If you wish we could solve
climate change some other way,
you’ve found your home. Because we do, too.

THE TEN NUMBERS

The Five CO2 Numbers

The Five Solar Geo Numbers

Neil Degrasse Tyson

2025 Isaac Asimov Memorial Debate
at the
American Museum of Natural History

”The Promises and Pitfalls of Solar Geoengineering”

If you already understand the ten numbers, and would like to learn more, we recommend exploring these sites next:

SCIENTIFIC REFERENCES

© 2025

After the Mount Pinatubo volcano erupted in 1991, the earth cooled by half a degree Celsius for the next two years.

Should we do something similar, now, on purpose?

The Story in Four Minutes

Nina Grant, Solar Geo Society Ambassador,PhD Candidate, Rutgers University

Our Mission:

Solar geo offers hope that we might cool the planet. Understanding the concept simply requires thinking about the difference between trillions, billions, and millions.

There will always be disagreements over the concept of solar geo (short for solar geoengineering). Our mission is for those disagreements to be better grounded in math and science.

The Five-Minute Counterargument

Raymond Pierrehumbert

Physics ProfessorOxford University

Perhaps the world’s most vocal academic physicist criticizing solar geo

If you wish we could solveclimate change some other way,you’ve found your home. Because we do, too.

THE TEN NUMBERS

The Five CO2 Numbers

1. There are over ONE TRILLION TONS of excess CO2 in the atmosphere.

2. That number gets worse every year by another 20 BILLION TONS.

3. That CO2 will remain in the sky for around A THOUSAND years.

4. We could plant trees. But even the most ambitious global ecosystem restoration plans aim for only A FEW BILLION TONS of additional CO2 removal per year.

5. We could build giant vacuum cleaners. But the entire global CO2 removal industry, taken as a whole, aims to draw down its first ONE BILLION TONS over the entire course of the next twenty years.

The Five Solar Geo Numbers

1. In 1991, after the eruption of the Mount Pinatubo volcano, global temperatures cooled by HALF A DEGREE CELSIUS, for the following two years.

2. Mount Pinatubo ejected around 20 MILLION TONS of sulfur dioxide into the stratosphere.

3. Scientists now talk about potentially building special planes to release around 5 MILLION TONS of sulfur dioxide per year, in order to approximately mimic the eruption of Mount Pinatubo.

4. We currently emit around 100 MILLION TONS of sulfur dioxide per year, in the form of air pollution near ground level.

5. Solar Geo will do ZERO to help us with ocean acidification, which is killing marine life, or with air pollution, which is killing five million people a year. Only ending our use of fossil fuels will solve these problems.

Neil Degrasse Tyson

2025 Isaac Asimov Memorial Debateat the American Museum of Natural History

”The Promises and Pitfalls of Solar Geoengineering”

A special note to those who still believe we need to “Keep 1.5 Alive!”

If you already understand the ten numbers, and would like to learn more, we recommend exploring these sites next:

SCIENTIFIC REFERENCES

The Ten Numbers Expanded With Scientific Citations

GRANT PROGRAM

© 2025

Nina Grant, Solar Geo Society Ambassador,
PhD Candidate, Rutgers University

Physics Professor
Oxford University

If you wish we could solve
climate change some other way,
you’ve found your home. Because we do, too.

2025 Isaac Asimov Memorial Debate
at the
American Museum of Natural History