Nostr notes by Zeke Hausfather

It will happily tell you the last there presidents and when they ...

2026-10-28T18:22:06Z

In reply to nevent1q…9nmg
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It will happily tell you the last there presidents and when they were elected, but only breaks when you specifically ask about 2020. Come on @Google, do better.

Google has specifically prevented its AI tool from telling users ...

2026-10-28T18:21:59Z

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)

This year's El Niño continues its climb into uncharted ...

2026-10-06T22:33:18Z

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).

I often see people claim that because clean energy sources like ...

2026-10-03T21:27:22Z

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:

I had a long (and fun) conversation with Nate Hagens about this ...

2026-09-30T16:14:11Z

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! https://youtu.be/_QtEETGsCw0?is=MFqMAIIP-ALqVduD

I have a new piece out in Nature today on the record-breaking ...

2026-09-22T17:40:19Z

I have a new piece out in Nature today on the record-breaking 2026/2027 El Niño, what impacts we should expect, and how governments can prepare. The Niño3.4 region is currently running more than 1C hotter than any prior event on record, and we remain months away from the peak https://www.nature.com/articles/d41586-026-02939-x

The August Niño3.4 numbers (ONI) came in at ~2.6C, a tad lower ...

2026-09-05T17:31:10Z

The August Niño3.4 numbers (ONI) came in at ~2.6C, a tad lower than most models predicted as temperatures largely stalled. This will likely change next week with some strong westerly wind bursts, but the trajectory may lead to a slight downward revision in September model runs.

Here is the RONI version of the plot: ...

2026-08-09T20:32:39Z

In reply to nevent1q…thht
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Here is the RONI version of the plot:

The August NMME runs are now in (though CFSv2 and CanSIPS have ...

2026-08-09T20:32:33Z

The August NMME runs are now in (though CFSv2 and CanSIPS have already been updated), and continue the trend of each month showing yet-higher model forecasts of an unprecedented El Nino by the end of the year:

The rise in Niño 3.4 region sea surface temperatures over the ...

2026-08-05T21:14:50Z

The rise in Niño 3.4 region sea surface temperatures over the past few weeks has been nothing short of astonishing.

We are now hotter than any days during the 1997/1998 super El Niño event, and we are still many months from the peak.

I'm not sure folks have realized just how crazy the second ...

2026-08-02T19:27:52Z

I'm not sure folks have realized just how crazy the second half of 2026 and 2027 will be for global temperatures – on the back of a record-smashing El Niño event. Here is my latest estimate of where both years will end up compared to global temperatures since 1850.

Both CanSIPS models have the relative Oceanic Nino Index (RONI) ...

2026-07-31T14:47:49Z

In reply to nevent1q…0pvf
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Both CanSIPS models have the relative Oceanic Nino Index (RONI) also well into record territory:

2026 El Niño models continue their inexorable march upwards. ...

2026-07-31T14:47:43Z

2026 El Niño models continue their inexorable march upwards. CanSIPS (which used to be among the cooler ones!) released their August runs today, and now show a Nov/Dec peak of 3.6C (CanESM5) and 4.2C (GEM-NEMO).

For reference, the prior record El Niño peaked at 2.8C.

The claim that "pink elephants cannot fly" is not an ...

2026-07-24T02:17:17Z

The claim that "pink elephants cannot fly" is not an evidence-based claim because studies have not ruled out the possibility that pink elephants can fly. 🙄

A recent viral graph found fewer days in the contiguous US above ...

2026-07-22T14:50:23Z

A recent viral graph found fewer days in the contiguous US above 95F/100F/105F today than in the 1930s.

But the graph is misleading – it fails to correct for changing measurement times and techniques, and overstates regional warmth. I take a deep dive at The Climate Brink: https://www.theclimatebrink.com/p/hot-days-cold-thermometers

For more details and figures (and details what this means for ...

2026-07-13T15:21:17Z

In reply to nevent1q…c8rr
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For more details and figures (and details what this means for 2026 and 2027 global temperatures), check out the full article over at The Climate Brink: https://www.theclimatebrink.com/p/the-strongest-el-nino-ever

One important caveat: the models have never been verified in this ...

2026-07-13T15:21:11Z

In reply to nevent1q…5c0h
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One important caveat: the models have never been verified in this territory. They have real, demonstrated skill at this lead time for ordinary events, but no ensemble has ever forecast a 3.5C El Niño because one has never happened.

We are both figuratively and literally in uncharted waters.

The model forecasts have become increasingly bullish on a super ...

2026-07-13T15:21:02Z

In reply to nevent1q…gs39
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The model forecasts have become increasingly bullish on a super strong El Niño as each new month has come in – and as we have firmly moved out of the "spring predictability barrier" that makes forecasting historically challenging earlier in the year.

If we instead look at the new relative oceanic niño index (RONI) ...

2026-07-13T15:20:53Z

In reply to nevent1q…sn6t
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If we instead look at the new relative oceanic niño index (RONI) that subtracts out warming across the tropical oceans, 11 of 14 models predict a record strong 2026/2027 El Niño event, with odds of a record sitting around 77%.

Currently 13 out of 14 dynamical models expect a record setting ...

2026-07-13T15:20:42Z

In reply to nevent1q…qexx
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Currently 13 out of 14 dynamical models expect a record setting event based on the Niño 3.4 region sea surface temperature anomalies (ONI), with overall odds of a record sitting at 91% across all 667 model ensemble members.

The 2026/2027 El Niño event has already grown faster than any ...

2026-07-13T15:20:36Z

In reply to nevent1q…fhu5
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The 2026/2027 El Niño event has already grown faster than any prior events (at least on an ONI basis). Here its observed and projected future evolution compared to the strongest prior El Niño events in recorded history.

With all the July model runs now in, it is very likely that 2026 ...

2026-07-13T15:20:30Z

With all the July model runs now in, it is very likely that 2026 will see the largest El Niño event since records began in the late 1800s – and potentially by a truly mind-blowing margin. The median estimate is now 3.6C, roughly 0.8C hotter than the prior record (2.75C).

https://www.theclimatebrink.com/p/the-strongest-el-nino-ever

There are some more technical quibbles: capacity shouldn't be ...

2026-07-11T22:25:21Z

In reply to nevent1q…7ckm
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There are some more technical quibbles: capacity shouldn't be compared with generation (e.g. 1 GW of solar is not the same as one GW of nuclear, its only 20-25% of the actual generation). Australia has done many things right but still has higher electricity prices on average than the US.

Many communities are banning new clean energy due to land use and ...

2026-07-11T22:25:15Z

In reply to nevent1q…z6l6
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Many communities are banning new clean energy due to land use and ideological concerns, and we both need to reform rules and do a better job of community engagement to address real concerns.

Similarly, the biggest barrier to near-term expansion of solar ...

2026-07-11T22:25:09Z

In reply to nevent1q…0tmc
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Similarly, the biggest barrier to near-term expansion of solar and other clean energy is less cost and more permitting and supporting infrastructure like transmission. Transmission in particular is a key unblocker for a high renewable grid and we are building less of it today than a decade ago.

While I agree with Bill that the fossil fuel lobby paid for a lot ...

2026-07-11T22:25:03Z

In reply to nevent1q…2x2w
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While I agree with Bill that the fossil fuel lobby paid for a lot of climate denial in previous decades, I see ideological opposition to clean energy (and climate action) as a much bigger barrier to progress today than fossil lobbyists.

I worry a bit that being too optimistic about progress to-date ...

2026-07-11T22:24:57Z

In reply to nevent1q…6van
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I worry a bit that being too optimistic about progress to-date will distract us from how much still needs to be done – and the important role of policy support and continued innovation. We are picking the proverbial low hanging fruits today, and the road to net-zero emissions remains long!

There are also sectors of the economy that will be harder to ...

2026-07-11T22:24:52Z

In reply to nevent1q…pxx8
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There are also sectors of the economy that will be harder to decarbonize, like industrial heat, cement, aviation, and agriculture, where renewable-powered approaches are generally not cost-competitive today (but there is a lot of innovation happening).

Most serious energy systems modelers see solar, wind, and ...

2026-07-11T22:24:46Z

In reply to nevent1q…xlsu
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Most serious energy systems modelers see solar, wind, and batteries representing the majority of generation in a net-zero world, but also see an important role for clean firm generation like enhanced geothermal, nuclear, and (potentially) gas with CCS.

Similarly, many places have big seasonal differences in ...

2026-07-11T22:24:41Z

In reply to nevent1q…3s05
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Similarly, many places have big seasonal differences in generation. In California where I live we get half as much solar generation in the winter compared to the summer. Seasonal storage is still quite expensive.

Solar can do a lot to displace daytime fossil fuel use, and ...

2026-07-11T22:24:34Z

In reply to nevent1q…qh4z
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Solar can do a lot to displace daytime fossil fuel use, and batteries can help it push into the evening, but solar + storage is not necessarily cheaper than gas in the US today. We shouldn't oversell how much folks electricity prices will decline near-term with renewables.

First, while I agree that the dramatic cost declines that ...

2026-07-11T22:24:28Z

In reply to nevent1q…las9
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First, while I agree that the dramatic cost declines that we've seen in solar and batteries over the past 15 years are a goddamn miracle, I'm a bit worried about folks underestimating how easy hard decarbonization will be in practice.

I enjoyed listening to Bill McKibben on Ezra Klein's show ...

2026-07-11T22:24:23Z

I enjoyed listening to Bill McKibben on Ezra Klein's show this week. Its refreshing to hear a strong case for a future of clean energy abundance and highlight a lot of positive energy trends.

That being said, there are a few points where I'd add some nuance to Bill's arguments.

Why is AC so rare in much of Europe? Well, until recently it ...

2026-07-10T16:27:25Z

Why is AC so rare in much of Europe? Well, until recently it simply wasn't hot enough to need it. Here is the average number of days above 30C (86F) for major cities over time:

Heat pumps are air conditioners. And air conditioners are ...

2026-06-26T17:30:00Z

Heat pumps are air conditioners. And air conditioners are (unidirectional) heat pumps. Opposing access to AC for ostensibly "climate" reasons is shortsighted, as they are a key adaptation technology to prevent suffering even while we continue to work to reduce emissions.

The world has warmed by around 1.4C since 1850. It took 148 years ...

2026-06-12T22:47:45Z

The world has warmed by around 1.4C since 1850.

It took 148 years for the first half of that warming to occur, and just 27 years for the second half!

Global CO2 emissions have plateaued since 2013, leading to a ...

2026-06-09T16:24:11Z

Global CO2 emissions have plateaued since 2013, leading to a slower growth in atmospheric CO2 than would have otherwise been the case. In a new analysis at The Climate Brink, I've taken look at what would have happened if emissions had continued to grow: https://www.theclimatebrink.com/p/plateauing-co2-emissions-have-slowed

March 2026 was the 4th warmest March on record for the ...

2026-04-02T15:10:59Z

March 2026 was the 4th warmest March on record for the planet's surface in the ERA5 dataset, coming in at 1.48C above preindustrial levels.

The new 2025 Global Carbon Budget finds that fossil fuel ...

2025-11-13T03:29:07Z

The new 2025 Global Carbon Budget finds that fossil fuel emissions will reach a new high in 2025. Total CO2 emissions (including land use) remain flat at 2024 levels.

While the land sink is up from 2024, carbon sinks are weakening: https://www.carbonbrief.org/analysis-fossil-fuel-co2-emissions-to-set-new-record-in-2025-as-land-sink-recovers/

In a UN speech today, President Trump said that "all of these ...

2025-09-23T17:02:14Z

In a UN speech today, President Trump said that "all of these [climate] predictions were wrong".

Back in 2019 I led a research effort to digitize old climate model projections and assess how well they did. Turns out they got future warming pretty spot on!

With only four months of the year still to report, I estimate ...

2025-09-07T15:01:32Z

In reply to nevent1q…28h5
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With only four months of the year still to report, I estimate that 2025 will be either the second (~33% chance) or third (~66% chance) warmest year on record. There is effectively zero chance that it will set a new record or be lower than the third warmest at this point.

August 2025 was the third warmest August on record after 2023 and ...

2025-09-07T15:01:26Z

August 2025 was the third warmest August on record after 2023 and 2024 at approximately 1.3C above preindustrial levels.

This continues a string of recent months a bit cooler than the exceptional 2023/2024 temperatures but warmer than any prior years.

Proud to be part of an effort by 85 scientists from around the ...

2025-09-02T17:29:07Z

Proud to be part of an effort by 85 scientists from around the world to respond to a misleading DOE climate science report last month.

The fact that our rebuttal is more than 3x the length of the DOE report is a good example of Brandolini's Law in action... https://sites.google.com/tamu.edu/doeresponse/home

Its only the high end warming outcomes of >4C that have become ...

2025-07-29T21:04:42Z

In reply to nevent1q…5a5m
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Its only the high end warming outcomes of >4C that have become increasingly unlikely as the world has moved toward lower emissions scenarios. The wide range of climate sensitivity and carbon cycle feedbacks still makes it impossible to rule out up to 4C: https://journals.sagepub.com/doi/10.1177/29768659241304854

Specifically, in our paper we argue that RCP4.5 or RCP6.0 are ...

2025-07-29T21:04:35Z

In reply to nevent1q…a76u
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Specifically, in our paper we argue that RCP4.5 or RCP6.0 are more realistic representations of 2100 warming under current policy than the increasingly implausible RCP8.5 scenario. But the lower of those two – RCP4.5 – gives a 2100 warming range of 1.8C to 4C!

The EPA cited my paper in their argument against the endangerment ...

2025-07-29T21:04:30Z

The EPA cited my paper in their argument against the endangerment finding today. However, their point is completely backwards: my paper actually supports the EPA's 2009 range of 1.8C to 4C warming by 2100. https://www.nature.com/articles/d41586-020-00177-3

"If you don’t worry about it now, it’s too late later on. ...

2025-07-11T16:27:06Z

In reply to nevent1q…ymvh
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"If you don’t worry about it now, it’s too late later on. [..]We are passing down extremely grave problems for our children, when the time to solve the problems is now"

Check out Sagan's 1985 congressional testimony on climate change here: https://www.youtube.com/watch?v=Wp-WiNXH6hI

Sagan really got the fundimental challenge of longer-term ...

2025-07-11T16:27:00Z

In reply to nevent1q…u9zn
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Sagan really got the fundimental challenge of longer-term problems like climate:

"Because the effects occupy more than a human generation, there is a tendency to say that they are not our problem — of course, then they are nobody’s problem..."

"The power of human beings to control and change the ...

2025-07-11T16:26:55Z

"The power of human beings to control and change the environment is growing as our technology grows. At present, we clearly have reached the stage where we are capable to make significant changes in the global climate."

-Carl Sagan, 1985

This comparsion in the NYTimes today is pretty stark. China is ...

2025-06-30T22:45:35Z

This comparsion in the NYTimes today is pretty stark. China is racing ahead to be a high-tech exporter of 21st century technologies, while the US is doubling down on being a petro-state exporting the technologies of the 19th century: https://www.nytimes.com/interactive/2025/06/30/climate/china-clean-energy-power.html

Is global warming accelerating? Over at The Climate Brink I argue ...

2025-06-30T17:06:37Z

Is global warming accelerating? Over at The Climate Brink I argue that the consilience of evidence from surface temperatures, climate models, forcing changes, ocean heat content, and earth energy imbalance all point toward yes: https://www.theclimatebrink.com/p/the-great-acceleration-debate

To put it another way, it takes the approach of actively ...

2025-06-28T15:23:52Z

In reply to nevent1q…ejdx
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To put it another way, it takes the approach of actively penalizing the technologies of the 21st century and subsidizing the technologies of the 19th century. As solar, batteries, and electrification are rapidly adopted by the rest of the world, we are stepping backwards.

The latest version of the Senate's BBB is a death sentence ...

2025-06-28T15:23:46Z

The latest version of the Senate's BBB is a death sentence for US energy leadership and a giant gift to China.

It eliminates tax cuts for solar that have been around since 2005, adds a new tax on solar after 2027, and creates a new direct subsidy for coal.

These 70% declines in Chinese SO2 emissions have occurred as the ...

2025-06-10T15:55:49Z

In reply to nevent1q…xdwy
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These 70% declines in Chinese SO2 emissions have occurred as the national government has brought in a series of air-pollution measures. These declines have added around 0.06C to global warming since 2006, or approximately 12% of the around 0.5C warming the world experienced between 2007 and 2024.

Clean air rules are driving a rapid decline in sulphur emissions ...

2025-06-10T15:55:43Z

In reply to nevent1q…ywsp
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Clean air rules are driving a rapid decline in sulphur emissions around the world. Global sulphur dioxide (SO2) emissions have fallen by around 40% since the mid‑2000s. Chinese SO2 emissions have fallen by more than 70% during that period.

There is around half a degree of warming today that is ...

2025-06-10T15:55:37Z

In reply to nevent1q…pkmn
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There is around half a degree of warming today that is “hidden” by aerosols. Without the cooling from sulphate and other aerosols, today’s global temperature would already be close to 2C above pre‑industrial levels, rather than the approximately 1.4C the world is currently experiencing.

Aerosols also have a substantial impact on human health, with ...

2025-06-10T15:55:31Z

In reply to nevent1q…ctcq
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Aerosols also have a substantial impact on human health, with poor outdoor air quality from particulate matter contributing to millions of premature deaths. Efforts to improve air quality around the world in recent decades have reduced aerosol emissions, bringing widespread benefits for health.

Human-caused emissions of aerosols – tiny, light‑scattering ...

2025-06-10T15:55:25Z

In reply to nevent1q…zf3c
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Human-caused emissions of aerosols – tiny, light‑scattering particles produced mainly by burning fossil fuels – have long acted as an invisible brake on global warming. This is largely because they absorb or reflect incoming sunlight and influence the formation and brightness of clouds.

I just published an explainer on aerosols and their role in the ...

2025-06-10T15:55:20Z

I just published an explainer on aerosols and their role in the climate that I've been working on for the past few months! It includes both how aerosols work, how emissions have changed, and how thats driven recent warming: https://www.carbonbrief.org/explainer-how-human-caused-aerosols-are-masking-global-warming/

Join us at 11 AM Eastern (8 AM Pacific) for a live Q&A and ...

2025-05-12T16:49:45Z

Join us at 11 AM Eastern (8 AM Pacific) for a live Q&A and the release of the Berkeley Earth April 2025 global temperature report: https://us02web.zoom.us/webinar/register/WN_k47CNFd5Q4aw6xJ13ptHFg#/registration

Large volcanic eruptions have a major climate cooling effect. But ...

2025-05-09T16:25:59Z

Large volcanic eruptions have a major climate cooling effect. But the eruptions we've had in the past 170 years have been relatively mild compared to those in the more distant past.

Here are climate model simulations of major eruptions since 1750 using FaIR:

it is.

2025-04-10T23:09:16Z

In reply to nevent1q…y5yg
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it is.

Here is how daily global temperatures have changed since the ...

2025-04-10T17:41:22Z

Here is how daily global temperatures have changed since the preindustrial (1850-1900) period in the Copernicus/ECMWF ERA5 dataset, with data through two days ago (April 8th):

Whenever I post about climate, skeptical folks inevitable respond ...

2025-03-24T19:26:01Z

Whenever I post about climate, skeptical folks inevitable respond with this graph. So I decided to do something radical: actually read the underling scientific paper and ask the authors.

As it turns out, it actually says the opposite of what skeptics claim: https://www.theclimatebrink.com/p/climate-skeptics-have-new-favorite

This record was unusual because it occurred during La Niña ...

2025-02-11T17:49:41Z

In reply to nevent1q…aape
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This record was unusual because it occurred during La Niña conditions, which have historically resulted in lower global January temperatures. January 2025 really stands out as anomalous compared to other La Niña years:

We've released the Berkeley Earth temperature update for ...

2025-02-11T17:49:36Z

We've released the Berkeley Earth temperature update for January 2025: https://berkeleyearth.org/january-2025-temperature-update/

It was the warmest January on record at 1.64C above preindustrial levels, and 0.09°C above the prior record set in 2024.

It is both the case that the 2% of the planet that is it United ...

2025-01-21T06:34:22Z

It is both the case that the 2% of the planet that is it United States is remarkably frigid at the moment, and that the world as a whole is at record-warm levels for this day of the year:

Scientists developed the first climate models in the late 1960s ...

2025-01-12T19:31:46Z

Scientists developed the first climate models in the late 1960s (for which the Nobel Prize in physics was recently awarded!).

How have these models held up against what happened in the real world after they were published? Surprisingly well, it turns out:

Great (and scary) visualization of 2024 daily temperatures ...

2025-01-10T18:30:35Z

Great (and scary) visualization of 2024 daily temperatures compared to prior years by the BBC today. Evocative of the iconic Joy Division album cover from 1979: https://www.bbc.com/news/articles/cd7575x8yq5o

A new perspective in Nature Climate Change argues that the ...

2024-12-04T18:48:03Z

A new perspective in Nature Climate Change argues that the discourse around climate tipping points risks "oversimplifying the diverse dynamics of complex natural and human systems and for conveying urgency without fostering a meaningful basis for climate action." https://www.nature.com/articles/s41558-024-02196-8

With ten months of the year now in, 2024 will be the warmest year ...

2024-12-02T23:35:42Z

In reply to nevent1q…te6f
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With ten months of the year now in, 2024 will be the warmest year on record in the ERA5 dataset, at around 1.59C (with a 95% confidence interval of 1.57C to 1.61C given uncertainty in December temperatures).

November 2024 was the second warming November on record in the ...

2024-12-02T23:35:36Z

November 2024 was the second warming November on record in the Copernicus ERA5 dataset, at 1.62C above preindustrial levels. It was second only to November 2023, which was 1.75C above preindustrial.

Has global warming accelerated in recent decades? If we look at ...

2024-12-01T16:44:19Z

Has global warming accelerated in recent decades? If we look at the rate of warming between 1970 and 2008 and extend it through present, we see that almost all years since 2015 are above the previous trend.

So what is the takeaway here? The weirdest aspect of the ...

2024-11-25T17:25:03Z

In reply to nevent1q…d8lh
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So what is the takeaway here? The weirdest aspect of the 2023/2024 El Niño event remains its early rise in global temperatures, occurring months before the peak of El Niño conditions. The persistence of high temperatures has been unusual, but the coming months will tell us just how unusual it is.

However, if we include more moderate El Nino events, there is one ...

2024-11-25T17:24:56Z

In reply to nevent1q…67pt
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However, if we include more moderate El Nino events, there is one in 1958 that saw a spike in global temperatures 12 months after the event peaked that is not too far off from what we are seeing today:

In a new post over at The Climate Brink I take an in-depth look ...

2024-11-25T17:24:50Z

In a new post over at The Climate Brink I take an in-depth look at how "weird" the recent El Nino event was. Compared to prior strong events, global surface temperatures rose earlier and high temperatures have persisted for longer: https://www.theclimatebrink.com/p/how-unusual-is-current-post-el-nino

Gavin Schmidt (@ClimateOfGavin) and I have a guest essay in ...

2024-11-13T17:41:45Z

Gavin Schmidt (@ClimateOfGavin) and I have a guest essay in today's New York Times about the exceptional and not fully explained recent global temperatures, and climate science can become more "operational" to address these questions: https://www.nytimes.com/2024/11/13/opinion/climate-change-heat-planet.html

yes, as far as we can tell: ...

2024-11-12T19:18:10Z

In reply to nevent1q…nmgg
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yes, as far as we can tell: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2021RG000757

As Glen notes, "The world has failed at 1.5°C, but this does ...

2024-11-12T17:59:23Z

In reply to nevent1q…q7sq
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As Glen notes, "The world has failed at 1.5°C, but this does not mean the world has failed. While crossing 1.5°C is a disappointing milestone, it does give the opportunity to reframe the problem. Staying aligned with the Paris Agreement ‘well below 2°C’ ambition is still very possible."

Is limiting the temperature increase to 1.5°C still possible? ...

2024-11-12T17:59:17Z

Is limiting the temperature increase to 1.5°C still possible? Yes, but only in a model.

Some new commentary by Glen Peters (@Peters_Glen) provides a fitting swan-song for our now-unachievable ambition: https://journals.sagepub.com/doi/10.1177/29768659241293218

For more details, see my write-up of the new paper over at The ...

2024-11-11T15:02:57Z

In reply to nevent1q…ah9v
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For more details, see my write-up of the new paper over at The Climate Brink: https://www.theclimatebrink.com/p/durability-of-carbon-dioxide-removal

But the science is clear: if we want to stabilize global ...

2024-11-11T15:02:52Z

In reply to nevent1q…45qa
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But the science is clear: if we want to stabilize global temperatures, only permanent removals (>1,000 years) can credibly neutralize ongoing emissions from fossil fuels, and it is important that our net-zero systems reflect this physical reality.

That said, less durable solutions still have a role to play. ...

2024-11-11T15:02:47Z

In reply to nevent1q…g4tx
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That said, less durable solutions still have a role to play. Temporary removals such as afforestation/reforestation can counterbalance land use emissions, and temporary reductions of warming have real value in minimizing peak temperatures.

Our new paper provides further evidence that credible net-zero ...

2024-11-11T15:02:41Z

In reply to nevent1q…hedz
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Our new paper provides further evidence that credible net-zero commitments require a like-for-like approach: https://www.annualreviews.org/content/journals/10.1146/annurev-environ-112320-105050.

Given 100,000-year+ atmospheric lifetime fossil CO2, it can only be credibly neutralized by permanent carbon removal.

If CDR only has a durability of 100 years (e.g. much of the CDR ...

2024-11-11T15:02:35Z

In reply to nevent1q…9yv0
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If CDR only has a durability of 100 years (e.g. much of the CDR market today), it would result in 1.1C more warming by 2500 in a scenario that otherwise stabilizes warming below 2C. CDR with a >1000-year durability is required to stabilize global temperatures.

In the study, published today in Nature Communications, we ...

2024-11-11T15:02:25Z

In reply to nevent1q…6u9n
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In the study, published today in Nature Communications, we simulate the climate impact of 6 GtCO2 of residual CO2 emissions at the point of net-zero (the typical value in scenarios examined in the recent IPCC report) under different durability assumptions.

We need carbon removal in addition to deep emissions reductions ...

2024-11-11T15:02:14Z

We need carbon removal in addition to deep emissions reductions to get to net-zero. But as we show in a new study the durability of removals is key to ensure net-zero actually stabilizes global temperatures and meets our climate goals: https://www.nature.com/articles/s43247-024-01808-7

Climate change is one of the defining challenges of the 21st ...

2024-10-30T17:29:31Z

Climate change is one of the defining challenges of the 21st century. While individual actions can reduce impacts, gov't policy will play a big role to make clean energy cheap and widespread.

The most important climate action you can take today is to vote.

2024 is now virtually certain to be the warmest year on record, ...

2024-10-28T15:20:01Z

In reply to nevent1q…z7kp
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2024 is now virtually certain to be the warmest year on record, and will be above 1.5C in most surface temperature datasets, including Copernicus/ECMWF's ERA5 shown here:

Here is the latest projection of where October 2024 will end up, ...

2024-10-28T15:19:54Z

In reply to nevent1q…5yr2
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Here is the latest projection of where October 2024 will end up, based on data for the first 26 days of the month:

Daily global surface temperatures have been trending upward over ...

2024-10-28T15:19:46Z

Daily global surface temperatures have been trending upward over the past month, and are now back in record territory for the first time since early September.

While October is very unlikely to set a new record, it will be close to what we saw in 2023.

New UNEP emissions gap report highlights a "massive gap ...

2024-10-24T15:24:20Z

New UNEP emissions gap report highlights a "massive gap between rhetoric and reality" and calls for a "quantum leap" in ambition to deliver Paris goals, as the world is way off-track today.

I cover the details over at @CarbonBrief: https://www.carbonbrief.org/unep-new-climate-pledges-need-quantum-leap-in-ambition-to-deliver-paris-goals/

Enhanced weathering is a promising technology to permanently ...

2024-10-16T15:26:57Z

Enhanced weathering is a promising technology to permanently remove CO2 from the atmosphere, improve soil pH, agricultural yields, and reduce N2O emissions, but is challenging to verify.

After a year of work involving 50 scientist, we have a firm roadmap for verification: https://cascadeclimate.org/blog/foundations-for-carbon-removal-quantification-in-erw-deployments

With 9 months of the year now behind us, 2024 is virtually ...

2024-10-02T20:31:55Z

In reply to nevent1q…tquf
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With 9 months of the year now behind us, 2024 is virtually certain to beat 2023 as the warmest year on record:

September 2024 started out roughly as warm as 2023, but while ...

2024-10-02T20:31:46Z

In reply to nevent1q…f7l6
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September 2024 started out roughly as warm as 2023, but while last year saw a massive spike in temperatures after the first week of the month up to ~1.8C, 2024 remained more consistently around 1.5C:

Here is how this month compares to all the other months in recent ...

2024-10-02T20:31:24Z

In reply to nevent1q…dfyz
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Here is how this month compares to all the other months in recent years. Global temperature anomalies have fallen a bit since the start of the year, but have remained stubbornly around 1.5C above preindustrial levels ever since May 2024.

September 2024 was the second warmest September on record, coming ...

2024-10-02T20:30:54Z

September 2024 was the second warmest September on record, coming in just above 1.5C relative to preindustrial levels in the Copernicus/ECMWF ERA5 dataset.

It was a ~0.3C warmer than any September prior to 2023 (which set an extraordinary high bar):

One year after the Patrick Brown hullabaloo, Grist has a nuanced ...

2024-10-01T22:15:49Z

One year after the Patrick Brown hullabaloo, Grist has a nuanced profile covering the event and its aftermath: https://grist.org/science/patrick-brown-profile-climate-scientist-criticized-study/

Since the 1950s, there has been a strong increase in heavy ...

2024-09-30T22:18:07Z

In reply to nevent1q…lrh4
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Since the 1950s, there has been a strong increase in heavy precipitation across the contiguous US, with the largest increases in Northeast, Midwest, and Southeast. These changes have contributed to increases in river and stream flooding in these regions. https://nca2023.globalchange.gov/chapter/2/

As we noted in the US 5th National Climate Assessment: "There ...

2024-09-30T22:18:01Z

As we noted in the US 5th National Climate Assessment:

"There is robust evidence that human-caused warming has contributed to increases in the frequency and severity of the heaviest precipitation events across nearly 70% of the US."