Zeke Hausfather
Climate scientist and energy systems analyst; writes The Climate Brink with Andrew Dessler and leads climate research at Stripe.
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What they believe
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There is a risk that off-grid gas generators will become locked in over long periods of time while the rest of the electricity generation system decarbonizes.
There is a real risk that off-grid gas generators become locked in over long periods of time while the rest of the electricity generation system decarbonizes.
theclimatebrink.comSaid 26 Oct 2026This on korrents
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There is a consilience of evidence that leads to the conclusion that current warming acceleration is likely real.
But as I’ve noted, there is a consilience of evidence that leads us to conclude that this time acceleration is likely real, even if it remains just short of statistically significant in surface temperature records.
theclimatebrink.comSaid 19 Oct 2026This on korrents
The bold line is korrents’ wording; the quote is theirs. These 2: what they wrote before what they said aloud, one per source, newest first.
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As its own page →Hiding
4 November
3 November
2 November
28 October
26 October
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Their words
There is a real risk that off-grid gas generators become locked in over long periods of time while the rest of the electricity generation system decarbonizes.
24 October
21 October
19 October
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korrents.com
There is a consilience of evidence that leads to the conclusion that current warming acceleration is likely real.Their words
But as I’ve noted, there is a consilience of evidence that leads us to conclude that this time acceleration is likely real, even if it remains just short of statistically significant in surface temperature records.
15 October
12 October
- Bluesky
- NewsletterThe strongest El Niño in a thousand years?
- Bluesky
10 October
6 October
5 October
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Their words
Many countries have already seen their power sector emissions decline, the world as a whole appears to now be on the cusp of absolute declines in electricity sector emissions.
3 October
28 September
22 September
From one piece My new NYT op-ed on climate change risk 2 beliefs · theclimatebrink.com
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Their words
The global land (where, its worth noting, we all happen to live) is warming around 50% faster than the world as a whole, and has already passed 2C.
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Their words
By 2150 we have a 77% chance of being above 3C, a ~30% chance of being above 4C, and a 6% of more than 5C warming.
28 August
From one piece What we can and cannot say about climate change and the Nepal disaster 3 beliefs · theclimatebrink.com
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Their words
But the existence of old events tells us nothing about whether the odds are changing, and heat waves happened in 1900 too (just less frequently).
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korrents.com
What drives glacial hazard risk is the rate of change in ice and permafrost, not the total amount of ice present.Their words
Rather, what drives risks is how fast the ice and the frozen ground beneath the ice are changing.
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Their words
A rapidly warming climate and retreating glaciers are increasing risks of these sorts of events in the region, whether or not we can ultimately attribute this particular event.
5 August
From one piece The real energy use of agentic AI 3 beliefs · theclimatebrink.com
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Their words
Unlike aviation, this is an end-use we already know how to decarbonize.
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Their words
Which is why the lever that actually matters most is the carbon intensity of the electricity.
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Their words
This is the Jevons paradox in action: making compute cheaper per token in turn tends to lead to greater levels of AI use.
30 July
From one piece Why Hansen may end up being right about 2026 2 beliefs · theclimatebrink.com
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Their words
it tells you that a single warm year, or even two, cannot distinguish between "very rapid acceleration driven by aerosols and high sensitivity" and "the trend and more modest acceleration plus a very strong El Niño."
Why Hansen may end up being right about 2026theclimatebrink.com
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Their words
I'd personally give a central estimate closer to 3.5C than Hansen's ~4.5C
Why Hansen may end up being right about 2026theclimatebrink.com
22 July
From one piece Hot days, cold thermometers 2 beliefs · theclimatebrink.com
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korrents.com
The US warming trend since 1970 is consistent across raw, adjusted, satellite, and surface temperature datasetsTheir words
The overall US warming trend (around 0.5F per decade since 1970 in max, min, and mean temperatures) is robust in every dataset, raw or adjusted, satellite or surface.
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Their words
A record set during an ecological disaster in one part of the country is not evidence that the whole country, much less the planet, was hotter.
17 July
13 July
Nothing matches.
Beliefs
Korrents What they believe 27 beliefs — each backed by an exact quote.
Each is a — compiled by korrents.com, not by them: the one-line wordings are korrents', the quotes are theirs.
Recent
There is a risk that off-grid gas generators will become locked in over long periods of time while the rest of the electricity generation system decarbonizes.
There is a real risk that off-grid gas generators become locked in over long periods of time while the rest of the electricity generation system decarbonizes.
Off-grid data centers have 60-80% higher emissions Said 26 Oct 2026
There is a consilience of evidence that leads to the conclusion that current warming acceleration is likely real.
But as I’ve noted, there is a consilience of evidence that leads us to conclude that this time acceleration is likely real, even if it remains just short of statistically significant in surface temperature records.
How not to detect warming acceleration Said 19 Oct 2026
Global electricity sector emissions may be on the cusp of absolute declines.
Many countries have already seen their power sector emissions decline, the world as a whole appears to now be on the cusp of absolute declines in electricity sector emissions.
The world without solar and wind? Said 5 Oct 2026
Show 24 more
There is a 77% chance of global warming exceeding 3C by 2150 under current policies.
By 2150 we have a 77% chance of being above 3C, a ~30% chance of being above 4C, and a 6% of more than 5C warming.
My new NYT op-ed on climate change risk Said 22 Sept 2026
The global land surface is warming approximately 50% faster than the global average.
The global land (where, its worth noting, we all happen to live) is warming around 50% faster than the world as a whole, and has already passed 2C.
My new NYT op-ed on climate change risk Said 22 Sept 2026
A warming climate and retreating glaciers are raising the risk of Himalayan ice-and-rock collapses regardless of whether any single event can be attributed to it.
A rapidly warming climate and retreating glaciers are increasing risks of these sorts of events in the region, whether or not we can ultimately attribute this particular event.
What we can and cannot say about climate change and the Nepal disaster Said 28 Aug 2026
What drives glacial hazard risk is the rate of change in ice and permafrost, not the total amount of ice present.
Rather, what drives risks is how fast the ice and the frozen ground beneath the ice are changing.
What we can and cannot say about climate change and the Nepal disaster Said 28 Aug 2026
The historical occurrence of extreme natural events does not by itself show whether their odds have changed over time.
But the existence of old events tells us nothing about whether the odds are changing, and heat waves happened in 1900 too (just less frequently).
What we can and cannot say about climate change and the Nepal disaster Said 28 Aug 2026
Making AI compute cheaper per token drives enough extra usage that total AI energy consumption rises rather than falls (a Jevons paradox effect).
This is the Jevons paradox in action: making compute cheaper per token in turn tends to lead to greater levels of AI use.
The real energy use of agentic AI Said 5 Aug 2026
The carbon intensity of the electricity grid, not compute efficiency, is the lever that matters most for AI's climate impact.
Which is why the lever that actually matters most is the carbon intensity of the electricity.
The real energy use of agentic AI Said 5 Aug 2026
AI's energy use is an easier end-use to decarbonize than aviation.
Unlike aviation, this is an end-use we already know how to decarbonize.
The real energy use of agentic AI Said 5 Aug 2026
Earth's equilibrium climate sensitivity to doubled CO2 is closer to 3.5°C than 4.5°C
I'd personally give a central estimate closer to 3.5C than Hansen's ~4.5C
Why Hansen may end up being right about 2026 Said 30 Jul 2026
One or two record-warm years cannot distinguish rapid aerosol-driven acceleration in warming from a strong El Niño riding on the existing trend
it tells you that a single warm year, or even two, cannot distinguish between "very rapid acceleration driven by aerosols and high sensitivity" and "the trend and more modest acceleration plus a very strong El Niño."
Why Hansen may end up being right about 2026 Said 30 Jul 2026
A regional climate extreme set during an ecological disaster is not evidence that the whole country or planet was hotter
A record set during an ecological disaster in one part of the country is not evidence that the whole country, much less the planet, was hotter.
Hot days, cold thermometers Said 22 Jul 2026
The US warming trend since 1970 is consistent across raw, adjusted, satellite, and surface temperature datasets
The overall US warming trend (around 0.5F per decade since 1970 in max, min, and mean temperatures) is robust in every dataset, raw or adjusted, satellite or surface.
Hot days, cold thermometers Said 22 Jul 2026
Raw, unhomogenized daily temperature records understate modern extreme heat because of historical instrument and observation-time changes
Third, raw daily data is the wrong tool for this question. Time of observation changes and the 1980s switch to MMTS sensors both suppress modern hot day counts relative to the past, and the raw and homogenized series diverge almost exactly when the instrument transition happened.
Hot days, cold thermometers Said 22 Jul 2026
Fuel buildup from forest mismanagement cannot occur in forests that were never actively managed
You cannot have a fuel-buildup from forest mismanagement in a forest you were never managing.
Canada's boreal wildfires aren't just bad forest management Said 17 Jul 2026
Local fuel treatments protect communities but cannot reduce total wildfire area across the remote boreal
Fuel management is valuable around communities, but is essentially useless across the remote boreal.
Canada's boreal wildfires aren't just bad forest management Said 17 Jul 2026
Warmer air dries out vegetation and dead fuel, priming landscapes to burn more easily
warmer air is exponentially "thirstier" (saturation vapor pressure rises ~7% per degree), so it pulls moisture out of live vegetation and dead fuels alike, priming the landscape to burn.
Canada's boreal wildfires aren't just bad forest management Said 17 Jul 2026
El Niño events typically peak near the end of the calendar year, between November and January.
El Niño almost always peaks near the end of the calendar year - typically between November and January, occasionally as early as October
The Strongest El Niño Ever Said 13 Jul 2026
A strong El Niño's peak warming effect on global surface temperature shows up three to five months later, landing in the following year.
global temperature lags ENSO by around three to five months, most of this event's warming will land in 2027, which is now shaping up to be a genuinely alarming year and the warmest on record by a sizable margin.
The Strongest El Niño Ever Said 13 Jul 2026
Strong agreement among forecast models does not by itself mean those models are skillful.
Model agreement this strong is unusual, though I'd note that agreement is not the same thing as skill as I discuss later on.
The Strongest El Niño Ever Said 13 Jul 2026
Cutting sulfur air pollution is now unmasking greenhouse-gas warming that aerosols had been offsetting.
As air quality regulations cut sulfur emissions, warming from greenhouse gases is being unmasked.
What drove the early 20th century warming? Said 9 Jul 2026
Since 1970, greenhouse gases explain essentially all observed global warming, with natural forcings and internal variability playing a negligible role.
since 1970, natural forcings have been roughly flat, internal variability averages out over the longer period, and greenhouse gases explain essentially all of the observed warming.
What drove the early 20th century warming? Said 9 Jul 2026
Atmospheric CO2 concentration is a lagging indicator of emissions trends, not a leading one.
Either way, atmospheric CO2 is better seen as a lagging rather than leading indicator of changes in emissions, as it is harder to see the effects of emissions reductions on concentrations over shorter time periods.
Plateauing CO2 emissions have slowed atmospheric growth Said 9 Jun 2026
Atmospheric CO2 concentrations will keep rising until global emissions are cut to less than half of current levels.
But broadly speaking we expect atmospheric CO2 to keep growing until we cut emissions pretty substantially (e.g. to <50% of current levels).
Plateauing CO2 emissions have slowed atmospheric growth Said 9 Jun 2026
Carbon sinks will weaken as the world warms, reducing how much CO2 they can absorb.
That being said, we still expect some weakening of carbon sinks in a warmer world - something we have started to see in the data.
Plateauing CO2 emissions have slowed atmospheric growth Said 9 Jun 2026
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Where they publish
Newsletter The Climate Brink The newsletter he writes with Andrew Dessler. Has a feed; the card shows only his own posts.
Two climate scientists working through what the latest data actually says — warming rates, model performance, what a given policy would and would not do.
Recent
- Off-grid data centers have 60-80% higher emissions 26 Oct 2026 A rush to power is leading data centers to install the least efficient and leakiest types of fossil gas generators rather than connecting to the grid
- How not to detect warming acceleration 19 Oct 2026 A new paper finding significant acceleration uses an inappropriate test with high false-positive rates
- The strongest El Niño in a thousand years? 12 Oct 2026 Tree rings and corals both put the biggest modern El Niños at or near the top of the past millennium, and this year’s event is on track to land well above them.
Show 9 more
- The world without solar and wind? 5 Oct 2026 Clean energy does not simply “add to” global energy use; it displaces fossil sources that would otherwise get built.
- The impacts of this year’s record-shattering El Niño 28 Sept 2026 El Niño will drive severe drought from Indonesia to the Southern Africa and northern South America, with wetter winters from the US Gulf Coast to Southern South America.
- My new NYT op-ed on climate change risk 22 Sept 2026 We’ve made real progress bending down the curve of emissions, but risks remain far too high for complacency
- What we can and cannot say about climate change and the Nepal disaster 28 Aug 2026 Formal attribution is premature, but the collapse happened on a rapidly warming mountain in a valley losing its ice
- The real energy use of agentic AI 5 Aug 2026 Agents use about 600x more energy than simple AI prompts
- Why Hansen may end up being right about 2026 30 Jul 2026 Whether 2026 sets a new record is increasingly likely to be a spit decision between different groups
- Hot days, cold thermometers 22 Jul 2026 Why a viral graph on US days above 95F is misleading and overstates regional warmth
- Canada's boreal wildfires aren't just bad forest management 17 Jul 2026 Higher fire season temperatures are strongly correlated with increased area burned
- The Strongest El Niño Ever 13 Jul 2026 With all the July runs in, dynamical models give a ~90% chance of a record-setting event
Link verified 20 Sept 2026. Recent items update automatically from the channel.
Bluesky @zekehausfather.com Their Bluesky account.
Recent
- Join me live tomorrow at 3 PM UK time for an “ask me anything” on my recent State of the Climate Q3 2026 update over at Carbon Brief: 4 Nov 2026
- With William Nordhaus' recent passing the field of climate economics has lost one of its giants. Nordhaus published in 1977 what was at the time a rather bold projection: the the world would warm by 1.2C by the year 2026. In reality it warmed by 1.1C. 3 Nov 2026
- October 2026 was the warmest October on record in Copernicus' ERA5 dataset, coming in at 1.75C above preindustrial levels. 2 Nov 2026
Show 17 more
- Google has specifically prevented its AI tool from telling users who won the 2020 presidential election, even though it happily tells us that Trump won in 2016 and 2024. This sort of political intervention into LLM responses is deeply problematic. (h/t to Charles Mann) 28 Oct 2026
- In the rush to build data centers, companies are starting to use their own off grid gas generators. This results in much higher emissions – 60% to 80% – compared with using their local electricity grid and risks locking in longer-term fossil dependence. 26 Oct 2026 theclimatebrink.com
- Great discussion with Olya Irzak on just how high the methane leakage may be from off-grid data centers powered by low-efficiency reciprocating gas engines. Another reason to ensure that if data centers are built, they are on the grid! 24 Oct 2026
- Join us tomorrow at 8 AM Pacific for the Berkeley Earth monthly press briefing. You can register here: 21 Oct 2026 us02web.zoom.us
- While there is increasingly strong evidence that global warming is accelerating, we need to be careful about how we detect it. Unfortunately a newly published paper on the topic makes a number of mistakes in it approach, as I discuss over at The Climate Brink: 19 Oct 2026
- Electric vehicle adoption is accelerating worldwide – but not in the United States: 15 Oct 2026
- Will this year's record-shattering El Niño event be the strongest in a millennium? In a new piece over at The Climate Brink I review the paleoclimate literature from tree rings and corals and argue that may well turn out to be the case: 12 Oct 2026
- There is a certain irony in spending $276 million on political “free speech”. 12 Oct 2026
- The October runs for dynamical El Niño models are now all out, and its a mixed bag. Some revise the event downward, some upward, but on average its still expected to peak at ~4C, albeit with the peak more likely to occur in December than November: 10 Oct 2026
- This year's El Niño continues its climb into uncharted waters; Niño3.4 region anomalies are now at a 3.4C above normal (how fitting!), higher than any prior El Niño event on record. September monthly Niño3.4 anomalies also set a record at 2.9C (beating 2015 and 1877's 2.75C). 6 Oct 2026
- I often see people argue that clean energy is not reducing emissions, because it just adds to rather than replaces fossil fuels. This argument is deeply misguided – clean energy built since 2005 has displaced 23 billion tons. I dive in over at The Climate Brink: 5 Oct 2026
- I often see people claim that because clean energy sources like solar, wind, or nuclear are manufactured using fossil fuels their emissions are high. But thats absolutely not the case: even accounting for full lifecycle emissions they are vastly better than burning coal or gas: 3 Oct 2026
- September 2026 was the second warmest September on record (after 2023's "gobsmackingly bananas" month), coming in at 1.63C above preindustrial levels in the ERA5 dataset. 2 Oct 2026
- Confused by all the debate about the new permitting reform bill? Here is a quick cheat-sheet of the most important provisions, and their likely impact on emissions: 30 Sept 2026
- The biggest barrier to emissions reductions is increasingly our inability to quickly build clean energy: solar, geothermal, wind, nuclear, transmission, battery storage, etc. Projects are held back by a thicket of regulations and reviews. 30 Sept 2026
- I had a long (and fun) conversation with Nate Hagens about this year’s El Niño, future emissions scenarios, climate uncertainty, mitigation, and a whole slew of other topics. Check it out! 30 Sept 2026
- Awesome to see @hollyjeanbuck.bsky.social get recognized with a MacArthur Foundation ‘Genius Grant’ today! 29 Sept 2026 macfound.org
Link verified 23 Sept 2026. Recent items update automatically from the channel.
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