What *actually* works — right here, right now — to address climate change? Here you go. This is the result of thousands of hours of painstaking research and analysis from the Project Drawdown team.

Gutted to hear of the passing of V. “Ram” Ramaswamy, who had led NOAA's influential climate lab, GFDL, since 2008. He had a truly American success story and lasting legacy. May his memory be a blessing to his friends and family.

Musk says not a single person has died due to him axing USAID. Sadly, part of my job involves tracking aid spending. So here’s a thread with just some of the people who lost their lives because of USAID cuts

any space weather experts with opinions on helioengineering? www.science.org/content/arti...

Europeans need to normalize an air conditioner culture quickly.

Obviously…

I don’t have strong opinions about how much money individuals should have, but elevating innovator to god status, with tremendous cultural and political leverage, is an enormous mistake. Especially as these are often some of the worst people. www.ft.com/content/77af...

Court blocks Trump/GOP/Project 2025 effort to dismantle NCAR: www.courtlistener.com/docket/72496...

It’s truly astonishing to see how comprehensively the US government is tearing down every part of the system that has made it up until now a world-leading power in science, research, and technological development. The entire world will suffer from this wanton destruction.

1/ I disagree a bit, but likely circle back to same conclusion as Katharine. SSPs are socioeconomic stories, not forcing scenarios. They become forcing trajectories when run through IAMs that integrate a bunch of assumptions with climate/energy/land systems to generate emissions scenarios.

In response to recent misinformation about the use of scenarios in IPCC reports: the IPCC does not conduct its own research, run models or make measurements. The IPCC’s role is to assess the available scientific, peer-reviewed literature relevant to climate change: www.ipcc.ch/2026/05/20/i...

No one is angry (in fact it’s good). The only story is a weird self-scripted narrative about the evils of climate science + highly inorganic & manufactured propaganda efforts to overstate importance & wake up a “skeptic” movement that hasn’t had anything useful to say in 20 years

This is a quick summary of the latest CMIP process. It is a complex beast and a consensus project so there are always things that you’ll agree with and those that you might not. 1/

My stab at today's radiative forcing vs. CMIP5/CMIP6 scenarios. "Observed" (at least as of 2024) doesn't quite exceed the highest scenarios that I've seen in other versions, partly due to anchoring scenarios to "obs" at 2005 (for RCPs) or 2014 (for SSPs). Not sure if that's the most sensible thing.

Worth saying in scenarioMIP that CH4 doesn’t increase much more in M, inc a lot in HL (and causes higher forcing than H until later in century) & higher C emissions correlated with less aerosol declines. There’s some degree of independence in these things, though, so not crazy to exceed M’s 6.5 W/m2

Two things can be true: • RCP8.5 was never a realistic "business as usual" scenario • The world has made real progress bending the emissions curve down Glen Peters, Piers Forster, and I explain in a new article: www.theclimatebrink.... 1/11

This is a good thread. I’d add that the word “plausible” has been doing a lot of work in recent days. Carbon emissions can go to zero tomorrow. This isn’t very “plausible” but there’s no rule of physics against it nor anything wrong with a scenario mapping out its consequences 1/

All projections are wrong, some are useful. Also the UN hasn’t done anything.

1/2 The KNMI in fact does not “rely” on 8.5, instead emphasizing the need to bracket extreme cases, and differentiate emissions from warming outcomes. www.knmi.nl/over-het-knm... www.knmi.nl/kennis-en-da...

I'm happy to share my new paper, in which I explore early Venus as a climate puzzle: how rotation, obliquity, eccentricity and a fainter young Sun shaped insolation and seasonal forcing before its greenhouse end state. link.springer.com/article/10.1...

While the usuals are overhyping the not new result that RCP8.5 is implausible this century, many things are on the table beyond 2100 and allowing for carbon cycle feedbacks. Fossil fuels use and reserves are uncertain. The climate story is still tied to human decisions.

climate-bsky...this figure from IPCC AR5 (fig9.42) showed no correlation between CMIP5 absolute global mean temperature and climate sensitivity. Has anyone made such a plot for CMIP6?

One aspect of climate modeling that is not intuitive to the public is how it’s actually very far from “all or nothing.” This is quite important for the usefulness of the endeavor and for constructing model hierarchies 1/

Planets: Earth, Venus, Titan, Jupiter, Saturn, Uranus, Neptune, Europa, Enceladus All other “moons” are in tiers. Io in tier 1. The Moon in tier 2 Kuiper Belt object: Pluto and many others Asteroids: Mercury, Mars

Hold on. We the taxpayers are going to pay companies $900 million, which is more than 6x what we spend on wind power R&D, to NOT build wind power at a time when electricity prices are spiking and we need more clean power?

Comedy show went well. The audience learned a little about planetary energy balance, the habitable zone, why we have oxygen in the air, the slow carbon cycle, and why Venus is cheap real estate on Zillow.

Does this mean the NASA budget cuts will be much smaller than advertised?

On today’s Earth Day, there’s much to celebrate, but not the vast industrial respiration project, in which humans consume oxygen to return CO₂ to the atmosphere from ancient, long-buried organic carbon, the very burial that helped give us the oxygen we breathe.

Some simple truths about methane vs. CO2. I've said this before, in various ways, in various peer reviewed papers, but I keep repeating it with variations hoping the message will get through somehow. (1) CO2 accumulates in the atmosphere. If you introduce a new CO2 emission source into the system

Former NASA climate scientist, now Senior Scientist at Project Drawdown, Dr. Kate Marvel, has a fantastic piece in the New York Times today. This is a must-read if you care about science, the planet, and the future. www.nytimes.com/2026/04/08/o...

I'm with Katie, Artemis isn't very scientifically interesting, but if it can boost interest & support for NASA science (which is just a fraction of the budget) I'm all for lots of pictures of eclipses. Maybe if DOGE came around after Artemis, funds wouldn't be spent on an empty building in NYC...

In PHM the radiative forcing in the next few decades is some -20 W/m2 (not sure how long the Sun keeps dimming). think you’d need to devote lots of resources to manufacture some sort of lab GHG that plugged up atmospheric windows while you try to figure out astrophage. 1/

No thick atmosphere around TRAPPIST-1 b and c from JWST thermal phase curves www.nature.com/articles/s41...

1/2 These comparison photos have been pretty popular over the last few days, I think to imply something about the dirtiness of the planet. Putting aside that the difference is due to photographic reasons and nightside viewing, etc, the Earth has less air pollution now and this is a good thing.

I was happy for the Southern-Hemisphere folks fo a minute that they finally had their moment of triumph, only for it to be grabbed again.

It must be amazing to be one of the few humans to see a solar eclipse, except with Earth doing the obscuring (from Orion spacecraft's window). I'm no photographer, but it seems impressive to grab the moon-lit nightside of Earth of this quality.

I love these views. It's hidden how fast they accelerate by the cameras tracking them, but they're going 10,000 mph only 5 and a half minutes after launch. And it still takes 6 days to get the moon. Space is big.

Don’t know what that molecule is but I wonder if ²H₂O (D₂O) or HDO can shed light on an ancient lunar magma ocean, and even speculative very early thin lunar atmospheres (e.g. www.sciencedirect.com/science/arti...). Some NASA GISS work explored this agupubs.onlinelibrary.wiley.com/doi/full/10....

I imagine this will always be the case. CH4 work is a lot of pipe tightening, leak fixing, landfill capping, and bovine digestive optimization. CO2 work is replacing the machinery of modern life without crashing the economy. Hard to do everything w mixed incentives & metrics that mix their effects.

Okay folks I've responded to the data center heat island paper. It is the worst study on AI and the environment I've ever read, by far. Thank you to @beijingpalmer.bsky.social for flagging. blog.andymasley.com/p/data-cente...

It’s simple. Focusing on CH4 is like obsessing over the noise of a concert but continuing to go work in heavy machinery at a construction site, with no earplugs, for most of your life. Or staying inside on a high air pollution day but smoking for decades. It’s great, but rather beside the point.

But under-discussed in the “thresholds” discourse is that it’s much different if one crosses some mark for 10 years than 1000 years.

For those in NYC, I'll be doing a bit about habitability at the Caveat comedy venue on April 25 www.caveat.nyc/events/nerd-...

The response of the forced climate system is remarkably simple.

Project Hail Mary is one of my favorite books, and a pretty good movie (though I have quibbles) but a key premise is that space-bacteria Astrophage "sees" CO2 spectral signatures in Venus' dense CO2 atmosphere, which it travels to for breeding. Although, it would see missing light, not extra light.

1/Some disagreements with this & Jim Hansen's post on the runaway greenhouse jimehansen.substack.com/p/runaway-cl...: 1) feedback math f=1 not necessarily runaway, it just means you need more terms in a Taylor series, a linear expansion isn't enough. It's just a local picture of the energy balance.

I know these were incredibly difficult samples to get and measurements to make and correct and I admire many of those involved, but I'm skeptical of the new low Pliocene CO2 values published today, especially in light of the boron CO2 proxy (not to mention a warmer-than-today Pliocene)

Interesting stuff. I also don't understand Eric Wolff's commentary about the ocean driving things on 10-100kyr+ timescales. The oceans don't have internal dynamics that evolve on those timescales.

OK, this is wild. In September 2023, geophysicists across the world started monitoring a very odd signal coming from the ground under them. It was picked up in the Arctic. And Antarctica. It was detected everywhere, every 90 seconds, as regular as a metronome, for *nine days*. What the HELL? 1/

As a rare climate scientist working in Silicon Valley, I've been drinking from the AI firehose a lot more than my peers. I thought it would be helpful to lay out my experiences of both the promise and pitfalls of using AI to accelerate scientific research: