Andrew Williams
@andrewilwilliams.bsky.social
Postdoc at UC San Diego | physics of climate 🌤️ 🌍 | PhD Oxford | views my own | he/him
andrewilwilliams.github.io
andrewilwilliams.github.io
The day-to-day confusion of a European living in the US
November 7, 2025 at 5:17 PM
The day-to-day confusion of a European living in the US
Reposted by Andrew Williams
Running a Global Ocean Model on a $300 Chromebook - A MOM6 Case Study: 🌊🧪 ocean2climate.org/2025/10/31/s...
Simulating the AMOC with MOM6 on a $307.97 Chromebook Plus … and also learning Python
For several years, I have been trying to find time and energy to learn GFDL’s Modular Ocean Model version 6 (MOM6), and Python program language. Finally, I have the time and energy to do so. …
ocean2climate.org
October 31, 2025 at 2:58 PM
Running a Global Ocean Model on a $300 Chromebook - A MOM6 Case Study: 🌊🧪 ocean2climate.org/2025/10/31/s...
Great to be here ☺️
Great to have @andrewilwilliams.bsky.social give the ATMO @tamuatmo.bsky.social Dept. seminar. Fantastic talk!
October 30, 2025 at 1:04 PM
Great to be here ☺️
Reposted by Andrew Williams
The idea that we somehow understand, or are likely to do so in the near future, even remotely how to dial in a particular magnitude of surface temperature change -- let alone rainfall -- is just not realistic (that's me being nice). 2/2
October 26, 2025 at 5:58 PM
The idea that we somehow understand, or are likely to do so in the near future, even remotely how to dial in a particular magnitude of surface temperature change -- let alone rainfall -- is just not realistic (that's me being nice). 2/2
Amen. Current climate models are not up to the task of predicting country-scale climate change, so the idea that we can build confidence in regional SRM effects using these same models has always seemed ridiculous to me.
My issue with SRM, leaving aside the equity and governance issues (which are IMO insurmountable), is that most (all?) of the research on SRM is based in models which struggle to agree on how even relatively recent volcanic events (our only albeit quite imperfect analog) affect surface climate. 1/2
October 26, 2025 at 7:27 PM
Amen. Current climate models are not up to the task of predicting country-scale climate change, so the idea that we can build confidence in regional SRM effects using these same models has always seemed ridiculous to me.
Reposted by Andrew Williams
New Global Tipping Points report from Lenton et al is out.
I haven't had a chance to digest all of it, but reading through the summary recommendations, it strikes me that the concept of 'tipping points' is needed for for very few of them --
I haven't had a chance to digest all of it, but reading through the summary recommendations, it strikes me that the concept of 'tipping points' is needed for for very few of them --
Global Tipping Points | understanding risks & their potential impact
Harmful tipping points in the natural world threaten humanity by disrupting life support systems and societal stability.
global-tipping-points.org
October 13, 2025 at 2:32 PM
New Global Tipping Points report from Lenton et al is out.
I haven't had a chance to digest all of it, but reading through the summary recommendations, it strikes me that the concept of 'tipping points' is needed for for very few of them --
I haven't had a chance to digest all of it, but reading through the summary recommendations, it strikes me that the concept of 'tipping points' is needed for for very few of them --
Reposted by Andrew Williams
Today my @nytimes.com colleagues and I are launching a new series called Lost Science. We interview US scientists who can no longer discover something new about our world, thanks to this year‘s cuts. Here is my first interview with a scientist who studied bees and fires. Gift link: nyti.ms/3IWXbiE
nyti.ms
October 8, 2025 at 11:29 PM
Today my @nytimes.com colleagues and I are launching a new series called Lost Science. We interview US scientists who can no longer discover something new about our world, thanks to this year‘s cuts. Here is my first interview with a scientist who studied bees and fires. Gift link: nyti.ms/3IWXbiE
Reposted by Andrew Williams
my takeaway from climate week nyc is that "climate storytelling" is a little too much "we must reimagine our deepest souls in relationship to mother nature and the moral abyss of the polycrisis into which we must now stare" and not enough "ok but get a heat pump"
September 28, 2025 at 6:52 PM
my takeaway from climate week nyc is that "climate storytelling" is a little too much "we must reimagine our deepest souls in relationship to mother nature and the moral abyss of the polycrisis into which we must now stare" and not enough "ok but get a heat pump"
Reposted by Andrew Williams
We’re advertising a PhD studentship for folks with good knowledge of Caribbean culture and society, with background in geography, human geography, humanities or interdisciplinary geosciences as part of our @leverhulme.ac.uk funded ‘volcanic histories’ project
October 7, 2025 at 6:54 AM
We’re advertising a PhD studentship for folks with good knowledge of Caribbean culture and society, with background in geography, human geography, humanities or interdisciplinary geosciences as part of our @leverhulme.ac.uk funded ‘volcanic histories’ project
Reposted by Andrew Williams
Workers keep dying from heat. Data from inside their bodies shows why. - The Washington Post. apple.news/AgzyHXvVjTEW...
Workers keep dying from heat. Data from inside their bodies shows why. — The Washington Post
Nearly half of Florida farmworkers’ bodies reached dangerous temperatures in one study — but short breaks pulled them back from the danger zone.
apple.news
October 4, 2025 at 1:30 AM
Workers keep dying from heat. Data from inside their bodies shows why. - The Washington Post. apple.news/AgzyHXvVjTEW...
Reposted by Andrew Williams
The Univ. of Nebraska’s Dept. of Earth and Atmospheric Sciences has established a webpage soliciting the community’s help in saving their program. Their hearing in front of campus admin is next Friday, Oct 10th. Please consider sharing why they’re essential!
eas.unl.edu/save-earth-a...
eas.unl.edu/save-earth-a...
Save Earth and Atmospheric Sciences! | Department of Earth and Atmospheric Sciences | Nebraska
The University of Nebraska-Lincoln is proposing to close the Department of Earth & Atmospheric Sciences (EAS) as part of its budget reduction plan. We strongly oppose this plan. EAS conducts research ...
eas.unl.edu
September 30, 2025 at 5:06 AM
The Univ. of Nebraska’s Dept. of Earth and Atmospheric Sciences has established a webpage soliciting the community’s help in saving their program. Their hearing in front of campus admin is next Friday, Oct 10th. Please consider sharing why they’re essential!
eas.unl.edu/save-earth-a...
eas.unl.edu/save-earth-a...
Reposted by Andrew Williams
Reposted by Andrew Williams
There's a really nice explanation (with clear graphics) in this @quantamagazine.bsky.social article of why most molecules in the atmosphere (oxygen & nitrogen) don't act as greenhouse gases, but a lot of the far less numerous ones (like carbon dioxide and methane) do. A great teaching aid :)
The Quantum Mechanics of Greenhouse Gases | Quanta Magazine
Earth’s radiation can send some molecules spinning or vibrating, which is what makes them greenhouse gases. This infographic explains how relatively few heat-trapping molecules can have a planetary ef...
www.quantamagazine.org
September 26, 2025 at 9:24 AM
There's a really nice explanation (with clear graphics) in this @quantamagazine.bsky.social article of why most molecules in the atmosphere (oxygen & nitrogen) don't act as greenhouse gases, but a lot of the far less numerous ones (like carbon dioxide and methane) do. A great teaching aid :)
Reposted by Andrew Williams
The GRFP announcement from NSF cuts out an entire cohort of 2nd year students from consideration, without warning. This is so deeply unfair that it warrants a formal protest from the scientific community. If someone wants to work with me to craft an open letter and solicit signatures, LMK.
New: After a long wait, the GRFP solicitation is live! Deadlines have been extended to early November, so applicants have a bit over a month to submit. www.nsf.gov/funding/oppo...
NSF Graduate Research Fellowship Program (GRFP)
www.nsf.gov
September 26, 2025 at 5:10 PM
The GRFP announcement from NSF cuts out an entire cohort of 2nd year students from consideration, without warning. This is so deeply unfair that it warrants a formal protest from the scientific community. If someone wants to work with me to craft an open letter and solicit signatures, LMK.
Reposted by Andrew Williams
I wrote a short piece on the debate about the future of climate modeling: Should we pool resources to do km-scale "masterpiece" runs or focus on using ML to build data-driven models that can still do large ensembles? 1/3
September 25, 2025 at 8:22 PM
I wrote a short piece on the debate about the future of climate modeling: Should we pool resources to do km-scale "masterpiece" runs or focus on using ML to build data-driven models that can still do large ensembles? 1/3
Reposted by Andrew Williams
this is sooooooo f'ing sweet. every time Sec. Chris Wright lies about the DOE Climate Working Group report, reporters cite our response.
September 26, 2025 at 12:22 AM
this is sooooooo f'ing sweet. every time Sec. Chris Wright lies about the DOE Climate Working Group report, reporters cite our response.
Reposted by Andrew Williams
New paper out. In which we helped the folks at the Allen Institute for AI (AI2) show that their climate emulator does a good (though not perfect) job at reproducing E3SMs' response to different SST boundary conditions.
1/
agupubs.onlinelibrary.wiley.com/doi/full/10....
1/
agupubs.onlinelibrary.wiley.com/doi/full/10....
Applying the ACE2 Emulator to SST Green's Functions for the E3SMv3 Global Atmosphere Model
The Ai2 Climate Emulator broadly captures the top-of-atmosphere (TOA) radiative response to local sea surface temperature (SST) anomalies ACE and EAMv3's global TOA radiation sensitivity to all S...
agupubs.onlinelibrary.wiley.com
September 25, 2025 at 5:30 PM
New paper out. In which we helped the folks at the Allen Institute for AI (AI2) show that their climate emulator does a good (though not perfect) job at reproducing E3SMs' response to different SST boundary conditions.
1/
agupubs.onlinelibrary.wiley.com/doi/full/10....
1/
agupubs.onlinelibrary.wiley.com/doi/full/10....
Reposted by Andrew Williams
interesting - More extreme Indian monsoon rainfall in El Niño summers www.science.org/doi/10.1126/...
More extreme Indian monsoon rainfall in El Niño summers
Extreme rainfall during the Indian summer monsoon can be destructive and deadly to the world’s third-largest economy and most populous country. Although El Niño events in the equatorial Pacific are kn...
www.science.org
September 23, 2025 at 4:21 PM
interesting - More extreme Indian monsoon rainfall in El Niño summers www.science.org/doi/10.1126/...
Reposted by Andrew Williams
Sorry, but disagree with @hausfath.bsky.social here. You open Pandora's box, you ain't closing it again. We've already seen with Paris that well intentioned international agreements do not translate into physical reality and SRM governance is a much harder problem. Zero is the only safe level. /1
I have a new @nytimes.com guest essay w/ @davidkeith.bsky.social about sunlight reflection. We note its not a solution for climate change and at best a band aid to treat systems, and suggest if its ever done it should only be to replace the cooling from air pollution today:
Opinion | A Responsible Way to Cool the Planet
A small, carefully scaled geoengineering program could compensate for the loss of cooling as we eliminate sulfur pollution.
www.nytimes.com
September 21, 2025 at 4:25 PM
Sorry, but disagree with @hausfath.bsky.social here. You open Pandora's box, you ain't closing it again. We've already seen with Paris that well intentioned international agreements do not translate into physical reality and SRM governance is a much harder problem. Zero is the only safe level. /1
Reposted by Andrew Williams
Verbatim: "White House spokeswoman Abigail Jackson described Mr Swain as a "longtime Democrat donor who has spent hundreds of dollars supporting liberal politicians, including loser Kamala Harris, with radical climate policies that the American people have repeatedly rejected."
Indeed. Earlier this summer, the White House did this to me, as a scientific expert source in media, and issued a formal statement regarding my personal campaign contribution history in an attempt to discredit my commentary on wildfire, climate, and federal policy. Yet more alarm bells ringing...
I had this exact same experience this morning. Same reporter as Heidi.
This is *not* normal.
I have spoken to the press on these issues for two decades. No government official has ever demanded to know my identity in order to give a comment on a story.
This is *not* normal.
I have spoken to the press on these issues for two decades. No government official has ever demanded to know my identity in order to give a comment on a story.
September 19, 2025 at 5:16 PM
Verbatim: "White House spokeswoman Abigail Jackson described Mr Swain as a "longtime Democrat donor who has spent hundreds of dollars supporting liberal politicians, including loser Kamala Harris, with radical climate policies that the American people have repeatedly rejected."
Reposted by Andrew Williams
Last week at the Italy–France border: moist valley air rising and forming near-surface clouds, while a higher cloud layer (with a cloud base of around 3,500 metres) tries to grow by convection, but fails to reach the rain stage. Beautiful!
September 15, 2025 at 6:32 AM
Last week at the Italy–France border: moist valley air rising and forming near-surface clouds, while a higher cloud layer (with a cloud base of around 3,500 metres) tries to grow by convection, but fails to reach the rain stage. Beautiful!
Reposted by Andrew Williams
EXCITING NEWS!
The Climate.us page has officially launched.
Here you will be able to read more about us, our plan, updates, see what real people are saying, view our news coverage, and of course find ways to take action.
We look forward to your continued support.
The Climate.us page has officially launched.
Here you will be able to read more about us, our plan, updates, see what real people are saying, view our news coverage, and of course find ways to take action.
We look forward to your continued support.
September 4, 2025 at 3:13 PM
EXCITING NEWS!
The Climate.us page has officially launched.
Here you will be able to read more about us, our plan, updates, see what real people are saying, view our news coverage, and of course find ways to take action.
We look forward to your continued support.
The Climate.us page has officially launched.
Here you will be able to read more about us, our plan, updates, see what real people are saying, view our news coverage, and of course find ways to take action.
We look forward to your continued support.
Reposted by Andrew Williams
I'm not sure many folks realize just how persistent the warming from CO2 is.
Here is a set of 1000-year climate model runs (using FaIR) simulating one year of CO2 emissions (40 gigatons in 2020); a millennia later the world has not cooled back down!
Here is a set of 1000-year climate model runs (using FaIR) simulating one year of CO2 emissions (40 gigatons in 2020); a millennia later the world has not cooled back down!
September 4, 2025 at 10:48 PM
I'm not sure many folks realize just how persistent the warming from CO2 is.
Here is a set of 1000-year climate model runs (using FaIR) simulating one year of CO2 emissions (40 gigatons in 2020); a millennia later the world has not cooled back down!
Here is a set of 1000-year climate model runs (using FaIR) simulating one year of CO2 emissions (40 gigatons in 2020); a millennia later the world has not cooled back down!
Reposted by Andrew Williams
nice article from Nadir Jeevanjee (is he on bluesky?) about predictions climate models got right. successful predictions are the gold standard of science.
5 forecasts early climate models got right – the evidence is all around you
theconversation.com/5-forecasts-...
5 forecasts early climate models got right – the evidence is all around you
theconversation.com/5-forecasts-...
5 forecasts early climate models got right – the evidence is all around you
From rising global temperatures to the fast-warming Arctic, early climate models predicted the changes half a century ago.
theconversation.com
September 4, 2025 at 1:07 AM
nice article from Nadir Jeevanjee (is he on bluesky?) about predictions climate models got right. successful predictions are the gold standard of science.
5 forecasts early climate models got right – the evidence is all around you
theconversation.com/5-forecasts-...
5 forecasts early climate models got right – the evidence is all around you
theconversation.com/5-forecasts-...
Reposted by Andrew Williams
I’m increasingly confident that these quotes are fully and intentionally fabricated, having searched extensively in both reports.
The quotes are framed to suggest that the IPCC *concluded* that natural variability undermines attribution of anthropogenic climate change.
FYI: It does not.
The quotes are framed to suggest that the IPCC *concluded* that natural variability undermines attribution of anthropogenic climate change.
FYI: It does not.
Made up quotes in the DOE CWG report?
In Ch8, authors claim to quote IPCC AR5 and AR6 summary statements suggesting difficulty attributing climate change due to decadal variability.
I suspected out-of-context, but I can't find the quotes (or anything like them) *at all*.
Anyone know any better?
In Ch8, authors claim to quote IPCC AR5 and AR6 summary statements suggesting difficulty attributing climate change due to decadal variability.
I suspected out-of-context, but I can't find the quotes (or anything like them) *at all*.
Anyone know any better?
August 30, 2025 at 7:57 AM
I’m increasingly confident that these quotes are fully and intentionally fabricated, having searched extensively in both reports.
The quotes are framed to suggest that the IPCC *concluded* that natural variability undermines attribution of anthropogenic climate change.
FYI: It does not.
The quotes are framed to suggest that the IPCC *concluded* that natural variability undermines attribution of anthropogenic climate change.
FYI: It does not.