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Christopher Callahan

@ccallahan45.bsky.social
3K followers 348 following 47 posts

climate scientist: extreme heat, health, attribution, climate in the courts. heat wave is two words. iuclimateandsociety.com

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Reposted by Christopher Callahan
New York Times Opinion @nytopinion.nytimes.com · 11/10/2026
"The age of accountability for the fossil fuel industry has just begun and has a bright future," Jeff Goodell writes. "The reason for that is the emergence of a powerful field of climate science known as attribution science." nyti.ms/4jcT2XS
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Christopher Callahan @ccallahan45.bsky.social · 11/10/2026
The Once and Future King!
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Reposted by Christopher Callahan
Eric Roston @eroston.bsky.social · 08/10/2026
El Niñissimo! www.bloomberg.com/news/article...
The Current El Niño Is Already Stronger Than Past Events
Sea surface temperature in the eastern tropical Pacific region monitored for El Nino activity

Chart shows Jan-Dec lines for the 1991-2020 average, 1997, 2015, 2023 and 2026, which flies way high above all the others in a kind of supernatural way. Y-axis is temperature in C, ranging from 30 down to 25.
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Christopher Callahan @ccallahan45.bsky.social · 08/10/2026
US committing national scientific suicide
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Reposted by Christopher Callahan
lauren @lauren.rotatingsandwiches.com · 08/10/2026
me: I dunno, I still like the guys on the team but I'm sympathetic to the argument seeing the Dodgers win in the playoffs every year is boring (braves fans start doing the chop) me: General McPherson I summon and bind thee to these boys' bats. Claim your vengeance
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Carl T. Bergstrom @carlbergstrom.com · 07/10/2026
Terry Tao @teorth.bsky.social: Indiscriminate brute-force application of AI to mathematics is depleting the field of good questions without renewing this resource or providing commensurate value. OpenAI: We hear you. Here's a .zip file with 377 hasty AI solutions to important open problems.
nytimes.com
OpenAI Releases Findings on 377 Math Problems, Further Roiling Field (Gift Article)
After a previous solution angered mathematicians, the company characterized the new release as being more responsive to concerns about A.I. disrupting research.
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Chris Hayes @chrislhayes.bsky.social · 07/10/2026
No AI for kids. Full stop.
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Christopher Callahan @ccallahan45.bsky.social · 07/10/2026
Well I wasn’t a fan of that either…But here, it’ll be harder to see the poster you want without bumping into people looking at the poster next to it. The hall is crowded enough to begin with. As with the talks, presenters are asked to work with less and less “space” (literally and figuratively)
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Christopher Callahan @ccallahan45.bsky.social · 07/10/2026
Sorry to the organizers who work really hard but this sucks
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Dan Garisto @dangaristo.bsky.social · 06/10/2026
NEW: In March the White House released an FY27 budget request that zeroed out the National Science Foundation's directorate of Social, Behavioral and Economic Sciences (SBE). For months it was unclear what would happen. Now, with FY26 over, the damage to SBE is coming to light. My reporting:
science.org
‘Complete devastation’: How NSF gutted its social sciences research
Agency body that funds sociology, linguistics, and archaeology studies in U.S. gave 90% fewer new grants this year
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Daniel Swain @weatherwest.bsky.social · 06/10/2026
Just did some number crunching using latest (Oct 1) ECMWF seasonal data, and I must say that I've never seen such high predictive confidence in a very wet California winter. This is a truly extraordinary forecast amid a record-strength El Niño event. [Thread: please read to end.]
Model-relative sea surface temperature anomalies for November 2026–January 2027. The supplied grid is displayed without added smoothing or coastal filling. Beige marks land and gray marks missing ocean values. The main colour scale spans -2 to +10°F, with white at zero. Hot pink marks anomalies above +10°F. This map does not establish an operational ENSO category.
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Christopher Callahan @ccallahan45.bsky.social · 06/10/2026
"Attribution science...helps us see a storm or a heat wave or a flood not as an act of a god or the whim of Mother Nature, but as a disaster that has been knowingly shaped or intensified by particular human actions." great piece by @jeffgoodell.bsky.social today www.nytimes.com/2026/10/06/o...
nytimes.com
Opinion | The Science That Has Oil Companies Running Scared
However the U.S. Supreme Court rules, the work of holding oil companies accountable for climate change has a bright future.
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Christopher Callahan @ccallahan45.bsky.social · 06/10/2026
"Attribution science...helps us see a storm or a heat wave or a flood not as an act of a god or the whim of Mother Nature, but as a disaster that has been knowingly shaped or intensified by particular human actions." great piece by @jeffgoodell.bsky.social today www.nytimes.com/2026/10/06/o...
nytimes.com
Opinion | The Science That Has Oil Companies Running Scared
However the U.S. Supreme Court rules, the work of holding oil companies accountable for climate change has a bright future.
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Christopher Callahan @ccallahan45.bsky.social · 06/10/2026
She has a song called Never Look Away which might be my favorite track of all time
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Bread @jacobreaded.bsky.social · 05/10/2026
Alternative phrasing:
Crying wojak: no you have to understand this is a very complicated system There are too many uncontrolled variables. we must accept certain downsides. 

Chad: Every road death is preventable
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Josh Gondelman @joshgondelman.bsky.social · 05/10/2026
I do not mean to single out LeBron James, but it feels completely bizarre to me that an active player is allowed to promote "prediction markets" but would get banned for life for using that service to bet ten dollars on their own team to win a game.
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Mark Histed @markhisted.org · 03/10/2026
Killed. NSF’s SBE was killed, in violation of law. The President does not have the power to choose to kill programs at a whim by defunding them. The imperial presidency was a mistake and we are in a separation of powers constitutional crisis.
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Erin J. Wamsley 🧠📈😴 @wamsleylab.bsky.social · 03/10/2026
The fiscal year is over. The dying Social, Behavioral, and Economic division of NSF ended up awarding 90 total grants this year, as opposed to ~700-800 in recent past years. Source: grantwitness.org/nsf/analyses...
The graph shows the cumulative number of awards made by month across this fiscal year, as compared to the last 6 fiscal years. The line for this year is total flat until June, but then finally gets up to 91 by October. In prior years the increase starts building earlier and ends on average in the 700-800 range (with variability, last year was only between 400-500).
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Mark Copelovitch @mcopelov.bsky.social · 03/10/2026
~Approximately no one in the general public knows because the leaders of the R1 research universities - whose budgets, programs, & personnel are entirely or significantly dependent on federal funding - have been totally absent from the public square in explaining & collectively protesting this.
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Christopher Callahan @ccallahan45.bsky.social · 02/10/2026
some have even compared this to the question of the meaning of life... www.nature.com/articles/s41...
nature.com
The question of life, the universe and event attribution - Nature Climate Change
Weather and climate service providers around the world are looking to issue assessments of the human role in recent extreme weather events. For this attribution to be of value, it is important that vu...
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Christopher Callahan @ccallahan45.bsky.social · 02/10/2026
great question tbh! One reason why I don’t work on hurricanes that much :) Storyline attribution studies often just try to quantify intensity change and say unconditional probability is not relevant/a separate question. But that may be unsatisfying for some settings/applications…
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Christopher Callahan @ccallahan45.bsky.social · 02/10/2026
“The patient is very sick, very vain, and almost unbelievably stupid; his heirs and viziers are loose throughout the world, trying to take as much as they can before any of the institutions notionally charged with stopping this sort of thing bestir themselves to mildly inconvenience that predation.”
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Adam Becker @adambecker.bsky.social · 01/10/2026
165 years ago TODAY, Charles Darwin had a normal one. "I am very poorly today & very stupid & hate everybody & everything. One lives only to make blunders.— I am going to write a little Book for Murray on orchids & today I hate them worse than everything…" I think about this letter a lot.
darwinproject.ac.uk
To Charles Lyell   1 October [1861] | Darwin Correspondence Project
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Elizabeth Lopatto @lopatto.bsky.social · 02/10/2026
Judith Butler Apology Form
Date:
Reason for behavior:
( ) The media convinced me that feminism was solved in the 1980s
( ) I miss not thinking about gender
( ) I was jealous of their nonbinary swag
( ) I never actually read their work
( ) I didn't realize how much of society is built on gender
( ) Mercury was in retrograde
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( ) I will hereby respect Judith Butler and I will NOT talk down on the best feminist thinker of our lifetimes
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Christopher Callahan @ccallahan45.bsky.social · 01/10/2026
the point about damage functions is just to say that because damage functions generally depend on event intensity and not frequency, they provide a basis for preferring intensity approaches over frequency ones if impact attribution is the goal
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Christopher Callahan @ccallahan45.bsky.social · 01/10/2026
oh sure, i agree - and at least my corner of the community has totally moved from using frequency-change approaches for impact attribution precisely for this reason. totally reasonable to think through the implications, but I would basically only ever use intensity approaches for this type of calc
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Christopher Callahan @ccallahan45.bsky.social · 01/10/2026
yes, nice paper - this is why it's important to have a credible damage function that directly relates event intensity to an impact of interest, and then attribute that intensity. storyline-type attribution is particularly good for this. we explore this more here: www.pnas.org/doi/10.1073/...
pnas.org
Quantifying the contributions of climate change and adaptation to mortality from unprecedented extreme heat events | PNAS
Understanding the mortality effects of the most extreme heat events is central to climate change risk analysis and adaptation decision-making. Accu...
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Christopher Callahan @ccallahan45.bsky.social · 30/09/2026
A very fitting and timely episode, as conservative forces are once again gearing up to steal the emails of scientists (including mine) to help avoid accountability for climate change impacts www.politico.com/news/2026/09...
politico.com
Inside the anti-climate campaign against researchers
A POLITICO investigation reveals more than 100 open records requests demanding documents from climate scientists nationwide.
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Reposted by Christopher Callahan
Ed BooOOooOOmila @edburmila.bsky.social · 30/09/2026
[SENATOR ERIC SCHMITT]: So you’re telling me under oath that you’ve never spoken with a bestselling author who is insane [JACK SMITH]: No [SCHMITT]: WELL THEN *unveils poster* please explain this picture of you with Naomi Wolf! [SMITH]: That is Naomi Klein sir
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Christopher Callahan @ccallahan45.bsky.social · 30/09/2026
Does this look similar if you do it for Nino3 instead of 3.4?
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Andrew Dessler @andrewdessler.com · 29/09/2026
Merchants of Doubt are going after extreme event attribution www.politico.com/news/2026/09...
politico.com
Inside the anti-climate campaign against researchers
A POLITICO investigation reveals more than 100 open records requests demanding documents from climate scientists nationwide.
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Reposted by Christopher Callahan
David Ho @davidho.bsky.social · 29/09/2026
Congratulations to my friend @hollyjeanbuck.bsky.social for being a 2026 MacArthur Fellow. I always knew she was a genius and this confirms it. 🥳
macfound.org
Holly Jean Buck
Investigating the social, ethical, and political dimensions of climate and energy policies and emerging technologies.
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Jessica Ellis @baddestmamajama.bsky.social · 29/09/2026
I have separated the art from the artist and am now whipping the art to stiff peaks, after which I will gently fold it into the artist before baking at 350 til golden and puffed
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Chelsea Harvey @chelseaeharvey.bsky.social · 28/09/2026
NEW - Conservative orgs are filing records requests by the dozens at public universities, demanding documents from climate researchers. @lesleyclark.bsky.social @corbinhiar.bsky.social & I have uncovered more than 100 requests, a campaign targets/allies say is an effort to derail climate litigation
politico.com
Inside the anti-climate campaign against researchers
A POLITICO investigation reveals more than 100 open records requests demanding documents from climate scientists nationwide.
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Lawrence Hurley @lawrencehurley.bsky.social · 28/09/2026
Major u-turn from Justice Alito as Supreme Court reveals he will no longer participate in the big climate change case being argued next week. Previously, the court told NBC News there was no reason for him to step aside despite his earlier recusal in same case.
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Marc Alessi @marc-alessi.bsky.social · 28/09/2026
New Commentary out in Nature Climate Action: we now live in a fundamentally different climate system due to the burning of fossil fuels. Because of this, any extreme weather event now occurs in a changed climate and is influenced by fossil fuel-driven climate change to some degree.
nature.com
The next phase of climate attribution - npj Climate Action
Attribution science has transformed our understanding of how anthropogenic emissions shape extreme weather events, yet the field remains constrained by repeatedly demonstrating anthropogenic influence...
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Bob Kopp @bobkopp.net · 26/09/2026
The literature about changes in nor’easters due to climate change is clear about two things: 1) more intense precipitation due to a warmer atmosphere, and 2) more extensive coastal flooding due to higher sea levels
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Christopher Callahan @ccallahan45.bsky.social · 25/09/2026
they also have another brother who not-so-subtly suggested that people over 75 should be euthanized
why i hope to die at 75
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Christopher Callahan @ccallahan45.bsky.social · 25/09/2026
in fairness i believe this is ari emanuel not rahm. though i am sure rahm is no less of a freak
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Christopher Callahan @ccallahan45.bsky.social · 25/09/2026
both coffin flop and the ghost of christmas way future are the hardest i have laughed in months
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Christopher Callahan @ccallahan45.bsky.social · 25/09/2026
NYT best TV list didn't include Slings and Arrows. completely illegitimate exercise
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Justin S. Mankin @jsmankin.bsky.social · 25/09/2026
"Pricing El Niño is not the same as preventing its loss of life. Yet, many of those acting on its forecasts are using them to move money, not people, out of harm’s way." My editorial for Science on why hedging El Niño is not the same as adapting to it: www.science.org/eprint/DU6FR...
science.org
Hedging El Niño isn’t the same as adapting to it
Record-setting warm waters slosh eastward across the tropical Pacific, forming El Niño. This recurrent climate pattern reconfigures severe weather worldwide, and with it, the global economy. Scientist...
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Christopher Callahan @ccallahan45.bsky.social · 25/09/2026
sorry this is not material to your point but we JUST started watching ITYSL and i finally ... get it
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David_j_roth @davidjroth.bsky.social · 24/09/2026
It's too depressing and obnoxious to write about, but virtually all of the doomy/horny AI hyperventilating is transparently displaced anxiety about our fucked climate and political situation. Even rich idiots know it's bad and being permitted to get worse. They're trying to write their own ending.
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samuel mehr @mehr.nz · 23/09/2026
after some in-depth discussions with my lab and also drawing on conversations on here, we've edited our new policy on AI usage in my lab feel free to adapt or re-use with attribution, or to reply to tell me how awful this policy is lol
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Dr. Jeff Masters @drjeffmasters.bsky.social · 22/09/2026
A classic El Niño impact: below-average monsoon rains in India. We're seeing a -15% deficit this year. India's top 5 rainfall deficit years all were during El Niño: 1877: -33% 1899: -29% 1918: -25% 1972: -24% 2009: -22% During moderate El Niño conditions in summer 2015, the deficit was -14%.
indiatoday.in
10 days left: Monsoon almost over, India's rain deficit at 15%, recovery bleak
India's southwest monsoon is entering its final phase with a 15 per cent rainfall deficit still in place. With withdrawal set to begin over parts of northwest India, the window for any meaningful reco...
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Henry Farrell @himself.bsky.social · 22/09/2026
www.programmablemutter.com/p/machine-go... what it says on the package
programmablemutter.com
Machine god metaphors eat your brain
There are other ways of thinking about AI
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Bob Kopp @bobkopp.net · 22/09/2026
NEW PAPER: In a new paper, jointly published in @agu.org Earth's Future & @ametsoc.org BAMS, and co-led by Melissa Kenney, @costasamaras.com and me, 175 authors outline priorities to guide the future of scientific assessments of climate change in the United States. 🧵
doi.org
Research Priorities for Robust Climate Assessments in the United States
A network of climate assessments plays a critical role in synthesizing the state of science to support evidence-based decision-making To support future U.S. and sub-national climate assessments, ...
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Steven (with a PH) @sjksalisbury.bsky.social · 20/09/2026
Christening a baby is nothing like christening a ship. I know that now. Once again I can only apologise.
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Philip Bump @pbump.com · 19/09/2026
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