Ken Caldeira

@kencaldeira.com

19K followers 3.6K following 1.5K posts

Mostly mentoring a group of postdocs at Stanford.
Senior Scientist at Gates Ventures.
climate / energy / etc
https://sustainablesolutions.stanford.edu/people/ken-caldeira

Posts imperfectly represent the views of my former self and not my employer. .. more

Videos

Kenneth Caldeira is an American atmospheric scientist. His areas of research include ocean acidification, climate effects of trees, intentional climate modification, interactions in the global carbon cycle/climate system, and sustainable energy. .. more

Environmental science 45%

Geography 15%

Posts Replies Media Videos

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Ken Caldeira @kencaldeira.com · Nov 18

Folks, I am really appreciative of people who have followed me and added me to their starter packs.

I post about climate science, energy system transition, and related issues.

I try to restrain myself to information and questions, and try to avoid unseemly opining in public.

Ken Caldeira @kencaldeira.com · 8h

It was about power and money all along.

Ken Caldeira @kencaldeira.com · 13h

Did you follow the link?

Ken Caldeira @kencaldeira.com · 13h

Epstein

Ken Caldeira @kencaldeira.com · 13h

Shockingly, according to polls, 42% of Americans approve of our felonious pedophile-in-chief.

I think this means that 42% of Americans are ignorant and get whatever news they get from Fox News, Newsmax, etc, and their echo-chamber friends and social media feeds.

www.nytimes.com/interactive/...

Poll showing President Trump with a 42% approval rating.

https://www.nytimes.com/interactive/polls/donald-trump-approval-rating-polls.html

Ken Caldeira @kencaldeira.com · 15h

Kavanaugh stops

Ken Caldeira @kencaldeira.com · 15h

Let's talk about anything other than the Epstein files.

www.theguardian.com/us-news/2026...

US congressmen ask judge to appoint official to force release of all Epstein files

Democrat Ro Khanna and Republican Thomas Massie seek to compel justice department to release full set of files

www.theguardian.com

Ken Caldeira @kencaldeira.com · 15h

Where are the Republicans denouncing Musk's calls for "white solidarity" and support for statements like "if white men become a minority, we will be slaughtered".

[crickets]

people.com/elon-musk-sh...

Musk quote-tweeting on X with a 100% "If White men become a minority, we will be slaughtered. Remember, if non-Whites openly hate White men while White men hold a collective majority, then they will be 1000x times more hostile and cruel when t..."

Ken Caldeira @kencaldeira.com · 16h

Where are the Republicans saying that you cannot disparage an entire ethnic group based on what some individuals have done?

[crickets]

The Republicans know no shame.

www.theguardian.com/us-news/2025...

Trump calls Somali immigrants ‘garbage’ as US reportedly targets Minnesota community

US president’s xenophobic rant comes amid reports of ramped-up deportation efforts in Ilhan Omar’s district

www.theguardian.com

Ken Caldeira @kencaldeira.com · 16h

The Republican Party has become an overtly racist party.

They are done with the "dog whistles" that only their neo-Nazi supporters can hear.

Now they are saying it out loud to all of us.

www.nytimes.com/2026/01/11/u...

Trump Says Civil Rights Led to White People Being ‘Very Badly Treated’

www.nytimes.com

Ken Caldeira @kencaldeira.com · 16h

Coral reef accumulation rates are probably on the order of 1% of anthropogenic CO2 emissions.

Our study was about the effect of atmospheric CO2 on coral reefs, not the effect of coral reefs on atmospheric CO2.

The effect of coral reefs on atmospheric CO2 is negligible on the century time scale.

Reposted by Ken Caldeira

Guardian US @us.theguardian.com · 17h

President’s memo stating US ‘shall withdraw’ from UNFCCC marks first time any country has tried to exit the agreement

Trump’s move to pull US from key UN climate treaty may be illegal, experts say

www.theguardian.com

The New York Times @nytimes.com · 18h

Breaking News: The EPA will stop considering lives saved when setting pollution limits and instead calculate only the cost to businesses.

E.P.A. to Stop Considering Lives Saved by Limiting Air Pollution

In a reversal, the agency plans to calculate only the cost to industry when setting pollution limits, and not the monetary value of saving human lives, documents show.

nyti.ms

Ken Caldeira @kencaldeira.com · 1d

I would have guessed the "global center" or "global centre" would have been several thousands of km down in Earth's core, but apparently there are quite a few global centers up here on Earth's surface.

www.google.com/search?q=Global+Center

www.google.com/search?q=Global+Centre

Google Search

www.google.com

Ken Caldeira @kencaldeira.com · 1d

Have you seen "In the Loop"?

A great satire from 2009 on the run-up to the Iraq War.

BBC Films etc so not a major Hollywood production, but very funny.

www.imdb.com/title/tt1226...

In the Loop (2009) ⭐ 7.4 | Comedy

1h 46m | Not Rated

www.imdb.com

Ken Caldeira @kencaldeira.com · 1d

Be careful.

They might shoot first and ask questions later.

Ken Caldeira @kencaldeira.com · 1d

Of course you are right that increased net coral calcification removes alkalinity from seawater, driving co2 to the atmosphere.

Of course the initial NaOH addition has the opposite effect.

Ken Caldeira @kencaldeira.com · 2d

Yes, that was our conclusion.

The increase in net calcification was independent of the net calcification indicating that the mechanism was decreased dissolution in under saturated microenvironments.

Ken Caldeira @kencaldeira.com · 2d

This post was connected to this thread, but I blocked someone who was making many annoying unfounded assumptions.

bsky.app/profile/kenc...

Blocking and muting freely is a way to improve the quality of your BlueSky feed. I recommend it highly.

Feel free to block me if you find me too annoying.

Ken Caldeira @kencaldeira.com · 2d

We reported on a much smaller alkalinity addition experiment back in 2016, when we found that alkalinity addition accelerated coral reef calcification.

As in this experiment, we too added sodium hydroxide.

(1/2)

www.nytimes.com/2026/01/08/m...

The Scientists Making Antacids for the Sea to Help Counter Global Warming

www.nytimes.com

Ken Caldeira @kencaldeira.com · 2d

Here is from Elizabeth Kolbert in The New Yorker in 2006:

www.newyorker.com/magazine/200...

Caldeira said that he had recently gone to Washington to brief some members of Congress. “I was asked, ‘What is the appropriate stabilization target for atmospheric CO2?” he recalled. “And I said, Well, I think it’s inappropriate to think in terms of stabilization targets. I think we should think in terms of emissions targets.’ And they said, ‘O.K., what’s the appropriate emissions target?’ And I said, ‘Zero.’

“If you’re talking about mugging little old ladies, you don’t say, ‘What’s our target for the rate of mugging little old ladies?’ You say, ‘Mugging little old ladies is bad, and we’re going to try to eliminate it.’ You recognize you might not be a hundred per cent successful, but your goal is to eliminate the mugging of little old ladies. And I think we need to eventually come around to looking at carbondioxide emissions the same way.”

Ken Caldeira @kencaldeira.com · 2d

Here is what I was writing in 2008: agupubs.onlinelibrary.wiley.com/doi/full/10....

Stabilizing climate requires near‐zero emissions

Current international climate mitigation efforts aim to stabilize levels of greenhouse gases in the atmosphere. However, human-induced climate warming will continue for many centuries, even after atm...

agupubs.onlinelibrary.wiley.com

Ken Caldeira @kencaldeira.com · 2d

My experience in that experiment made me extremely skeptical that ocean alkalinity addition was a plausibly a feasible and positive response to the climate problem.

@valentenya.bsky.social, I think you may be making a lot of unfounded assumptions.

Ken Caldeira @kencaldeira.com · 2d

We were demonstrating adverse consequences of ocean acidification on coral reefs.

Ken Caldeira @kencaldeira.com · 2d

"Here was buried

Thomas Jefferson

Author of the Declaration of American Independence

of the Statute of Virginia for religious freedom

& Father of the University of Virginia"

www.monticello.org/research-edu...

Jefferson's Grave and Tombstone

Jefferson left instructions for the building of his tombstone, which included listing what he considered his three greatest achievements and an obelisk design.

www.monticello.org

Ken Caldeira @kencaldeira.com · 2d

Here is a link to our paper:

www.nature.com/articles/nat...

We developed elegant methods to detect the biological response.

This was the first time that I know of where the biological response to a chemical perturbation in the ocean was measured in the absence of artificial confinement.

2/2

a, Map of Australia and aerial photograph of One Tree Reef with the study area denoted by an orange square. The map, sourced under Creative Commons CC0, is freely available for commercial use. Use of the photograph was permitted under an Educational license from the University of Sydney. b, c, Cross-sections of the reef along the yellow line are shown for high (b) and low (c) tides, demonstrating the unidirectional flow from the upper lagoon (First Lagoon), over the reef flat study area, and into the lower lagoon (Third Lagoon) during low tide. d, Schematic of the study area (to scale) indicating the positioning of the transects and sampling locations (blue circles).

https://www.nature.com/articles/nature17155/figures/1

Ken Caldeira @kencaldeira.com · 2d

The Scientists Making Antacids for the Sea to Help Counter Global Warming

www.nytimes.com

Ken Caldeira @kencaldeira.com · 2d

Trump really doesn't want you to be talking about his role in the Epstein files.

Speaker Mike Johnson said Trump was an informant for the FBI.

Informants typically provide information as part of a non-prosecution agreement.

Nick (derogatory) ✨ @slothropsmap.bsky.social · 2d

I think we’re at the Rubicon.

Who knows, of course, but it feels like what happens over the next few weeks will define the rest of our lives.

Trump 'orders US army chiefs to draw up plan to invade Greenland'

Donald Trump has ordered his special forces commanders to draw up a plan for the invasion of Greenland - but is being resisted by senior military figures, The Mail on Sunday has learned.

www.dailymail.co.uk

Reposted by Richard S.J. Tol, Ken Caldeira, Michael A. Clemens , and 4 more Richard S.J. Tol, Ken Caldeira, Michael A. Clemens, Rosemary A. Joyce, Daniel W. Drezner, Simon Lester, Nathan P. Kalmoe

Nick (derogatory) ✨ @slothropsmap.bsky.social · 2d

I think we’re at the Rubicon.

Who knows, of course, but it feels like what happens over the next few weeks will define the rest of our lives.

Trump 'orders US army chiefs to draw up plan to invade Greenland'

Donald Trump has ordered his special forces commanders to draw up a plan for the invasion of Greenland - but is being resisted by senior military figures, The Mail on Sunday has learned.

www.dailymail.co.uk

Ken Caldeira @kencaldeira.com · 2d

49.1% of the US population is male, and 58% identify as non-Hispanic white, so white men are already a minority in the US, making up 28.5% of the population.

But, maybe women don't count.

(Globally, white males are ~4% of the population, yet they seem a bit over-represented in positions of power.)