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Robinson Meyer:
[1:26] Hi, I’m Robinson Meyer, the founding executive editor of Heatmap News. It is Friday, March 20. Earlier this month, China released the draft outline of its next five-year plan, which sets out the country’s development pathway for 2026 to 2030. The plan is a big deal. China remains the world’s number one climate polluter, but its greenhouse gas emissions have been flat or declining for the past two years, depending on how you count. Its clean energy industry, and particularly its electric vehicle industry, is now the envy of the developed world. At the same time, as we’ve covered on this show, China has re-embraced coal in the past five years as part of an energy security push that has kept its emissions from falling as fast as they otherwise might have. In particular, the country has built these huge, new, and unbelievably carbon-intensive facilities that convert coal into petrochemicals. These are somewhat, frankly, duplicative factories within the country that were meant to protect China if the global oil trade were to ever shut down or suffer some kind of crisis. And while these factories might have been built to give the country some leverage over Taiwan and the United States, they’re coming in handy now given the current global energy crisis caused by the closure of the Strait of Hormuz.
Robinson Meyer:
[2:38] Given all of that context, I think the five-year plan doesn’t lean into clean energy as much as some might have hoped. In the new outline, China says it wants to keep expanding the massive clean energy bases in the country’s interior. These are huge rural areas that are connected to its coastal cities by huge long-distance transmission lines. China’s made it very easy to build wind and solar power there. The new plan also says China should build what it calls a quote, new type power system, unquote, which would incorporate variable wind and solar, smart grids, batteries, large-scale long-distance transmission.
Robinson Meyer:
[3:13] China wants to build 100 gigawatts of offshore wind capacity and another 100 gigawatts of pumped hydro storage. It thinks it will add 10 gigawatts per year of new nuclear capacity along the coast, which is actually a bit of a slowdown. The new five-year plan, though, doesn’t say a lot about coal. And while it calls for promoting the peaking of coal and oil consumption, that’s actually a bit of a walkback compared to what the country was saying in 2021. As you’ll hear, China’s also revised how it accounts for its carbon emissions in ways that are pretty politically convenient and may allow the country to hit Paris Agreement goals that it wasn’t on track to meet.
Robinson Meyer:
[3:50] So there’s a lot to talk about here. It’s a very important document. It helps us understand where the world’s biggest air polluter thinks it’s going in the next five years. It also helps us understand the direction of the global energy industry over the next five years, given that China is both the number one consumer of fossil fuels globally and also the number one producer of clean energy. And here to talk about it today, I am joined by one of the world’s greatest experts on Chinese emissions outside of China.
Robinson Meyer:
[4:17] Lauri Myllyvirta is the lead analyst and co-founder of the Centre for Research on Energy and Clean Air, which is an independent research organization headquartered in Finland. It produces some of the most respected and cited independent assessments of China’s greenhouse gas emissions. I’ll say ’s work and the center’s work is behind a lot of the headlines you’ll see about China’s falling emissions, about its carbon intensity, about its energy future. If you ever see like a news story at the New York Times or the BBC or heat map about the direction of China’s emissions, actually, the Centre for Research on Clean Air’s assessments are probably somewhere in there. We had a great conversation with Lauri last year on Shift Key, so I’m excited to welcome back to the podcast. This time, we get into the new five-year plan, what actually drives China’s energy policy, and whether China is keeping the climate promises that it’s made. We also talk about what the closure of the Strait of Hormuz and this new global energy crisis could mean for China. It is always good to talk to Lauri. I had a lot of fun with him. This time, let’s go to that conversation now. All of this and more. It’s all coming up today on Shift Key. Lauri Myllyvirta, welcome to Shift Key.
Lauri Myllyvirta:
[5:27] Thanks so much. Thanks for having me.
Robinson Meyer:
[5:29] So China recently released its new five-year plan. Looking at this plan through the point of view of global decarbonization, was the plan good or bad news?
Lauri Myllyvirta:
[5:40] I think it was very much expected with a few surprises, but overall, it’s really a continuation of the theme of pursuing an ambitious build-out of clean energy industries, manufacturing, technological development, and overall building the basis for a decarbonized power system. There was one quite specific bit of that news, which was that China had been falling quite badly behind on its carbon intensity targets, which are the key targets that China has set under the Paris Agreement for 2030. And so there was a question of how is the country going to get back on track? And the answer is that they did that by revising the numbers to date rather than by setting a stronger target for the next five years to make up for what had seemed like a shortfall before the new numbers came out.
Robinson Meyer:
[6:44] When we look at these goals, it seems like sometimes they’re linear extensions of trends that are already in place. They’re goals that would be very hard to miss because in some cases, the concrete’s already being poured for the scale of nuclear buildout, for instance, that the planet imagines or the production capacity already exists to make the scale of solar panels, for instance, that would need to be installed. But it also does seem that these goals do serve as useful targets for the Chinese economy, for Chinese local and provincial planners, how does the five-year plan kind of trickle down into actual economic outcomes and how does it shape them?
Lauri Myllyvirta:
[7:23] Right. That is a very good question. A lot of that is soft signals about priorities rather than hard numbers, especially when we’re talking about this top-level plan. So this is the draft of the outline of the five-year plan that we’re talking about right now. So this will inform five-year plans for the provinces. This will inform five-year plans for all the different sectors prepared by different ministries, prepared by state-owned enterprises, and so on. And during the five-year period, these priorities inform financing, lending decisions, and a whole host of other decisions around the country. And again, this is much more about the soft signals. Also, if a specific technology gets a mention that it’s to be vigorously promoted, then that just tells you, like tells every banker in the country that when there’s a loan application on your desk for this specific tech, then you should
Lauri Myllyvirta:
[8:29] view it more favorably, and so on. So in that sense, those signals do trickle down in a lot of ways. And so then if you think about some of the technologies that did get such a mention in the five-year plan, so that would be, for example, green fuels, synthetic fuels made with green electricity. And so that’s something that this five-year plan signals is going to start happening a lot faster than was previously anticipated so the standard way to think about the clean energy transition is that you first build as much clean power as the grid will take get the grid very clean and then only after that you start to think about how do you convert that clean electricity into fuels to replace those bits of fossil fuel use that can’t be electrified but this is starting to happen a lot faster and it reflects a couple of different things so one of them is concerns about how fast you can reform and overhaul the grid to be able to take as much clean power as is being built at the moment. And the other one is shifting priorities. So more focus on replacing imported oil and gas because of the energy security concerns. So for both of these reasons, it makes sense to start building up this industry.
Robinson Meyer:
[9:49] When you were last on the show, we were talking about the rise of the coal to chemicals industry in China. And in some ways, it seems quite prophetic because of what’s now happened with Hormuz. And we can talk about that in a second. But what does the plan suggest about China’s goals for the coal industry And does the plan suggest that Chinese leaders understand the coal industry to be in secular decline? Or do they see it as like a core part of the energy security package for the country?
Lauri Myllyvirta:
[10:18] There’s very little about coal in this five-year plan document. So obviously, there will be a coal industry five-year plan and a chemical industry five-year plan and so on. Later on, What is more notable is what isn’t there on coal. Xi Jinping had said earlier in 2021 that China would, during this five-year period that’s now starting, would gradually reduce coal consumption.
Lauri Myllyvirta:
[10:46] And that line is not there. It’s been replaced by promoting the peak of coal consumption. And there was also a bit of nuance on that because this line came out already in the autumn from the central committee of the communist party and the official news agency ran a Q&A piece on what that means before the conference where the five-year plan was to be adopted and they explained that what it actually means is that coal consumption should reach a plateau in 2027 and coal consumption in the power industry, so coal-fired power generation and coal consumption in the chemical industry, so coal-to-chemicals would continue to grow beyond this 2027 peak date. So the idea is that coal consumption would be reduced in the other sectors, other heavy industry sectors and so on. But the current downtrend in coal-fired power generation would turn into another period of growth and coal consumption in the coal to chemicals industry would continue to grow rapidly.
Robinson Meyer:
[11:59] So interesting. And also it kind of turns on the fact that my understanding, part of what’s happening here is that these phrases kind of circulate at the highest level and she may say them or another kind of national leader may say them and then they assume a kind of totemic quality, but sometimes their deeper Talmudic meaning needs to be spelled out by a lower entity that says exactly kind of what this totemic phrase is supposed to mean.
Lauri Myllyvirta:
[12:27] Yeah, absolutely. But one thing that has happened is that ministries seem to have a lot less leeway to interpret and take these things further. When something has been announced by President Xi personally as the timeline for carbon peaking and so on has been, then it’s very hard for lower level officials to make tweaks to that. And I think that the low ambition for clean energy in the plan signals this overall. So basically, if you take the clean energy targets in the plan at face value, they would mean significantly slowing down, significantly reducing the amount of clean energy that is added every year, which I don’t think the policymakers really want or anticipate. But the plans have to maintain this storyline that emissions have been growing but they haven’t for the past two years but so they will go back into growth and then only start peaking towards 2030 because that’s the official timeline.
Robinson Meyer:
[13:35] There’s a lot of excitement online, and I think in some parts of, let’s say, like the Western or international left, about China establishing a new kind of global energy regime, and that China’s claim to some kind of global leadership status or quasi-hegemony is premised on its clean energy industry, on its batteries, on its EVs. Do China’s leaders seem to embrace that vision as represented in this plan or other recent rhetoric from them?
Lauri Myllyvirta:
[14:05] They have increasingly started to do that. So China’s leaders have been very cautious of claiming any kind of leadership. There was, in fact, a major debate about this about five years back. Can China claim to be a leader and have been very conscious of the-
Robinson Meyer:
[14:23] In climate change or globally and politically?
Lauri Myllyvirta:
[14:26] Exactly. And so then the line that they landed on in 2020 was that China is a major contributor to the global effort on climate, but it’s a leader on building ecological civilization.
Lauri Myllyvirta:
[14:41] Which is a project that obviously China can own and define. But so the whole point here is that China’s leaders have been very aware of the expectations that they would set by claiming leadership and have been wary of doing that. But so in 2025, China’s diplomats and even Xi Jinping himself started to emphasize China’s role as a supplier of clean tech to the rest of the world and started to embrace that message. And that’s a significant reimagining of China’s role in the world. And I do think there is some truth to China creating a new paradigm. So So this approach that I called supply-side climate policy, so making clean energy, solar, energy storage, electric vehicles, so competitive, so affordable, that they become the preferred way for a lot of developing and emerging countries to pursue modernization, industrialization, growth, and an alternative to the fossil fuel-based path of pursuing those things. And this message of pro-growth, clean energy has obviously a lot of appeal in countries that want to develop and industrialize.
Robinson Meyer:
[16:07] I guess what I’m asking is, it sounds like China’s leaders are both talking about China as a global leader or global contributor to climate action, but also maybe not leaning into it in the same way in this five-year plan outline as much as they could have. And or they talk about scaling up clean energy but they also talk about scaling up lots of other technologies needed for this kind of primary goal of energy security such as the coal to chemicals industry or the coal industry or the green fuels industry can you just like walk through that tension a bit between energy security and climate change what do china’s leaders emphasize more And when China’s leaders kind of imagine, to the extent we can get into this, obviously, but like when China’s leaders imagine a future global security regime in which China plays a larger role, do they see these clean energy technologies as essential to that new order? Or do they see energy security kind of coming first and the clean energy technologies are a tool to achieve that energy security? But so is the coal to chemicals industry, this enormously carbon intensive and often duplicative industry that China seems to have spun up entirely for energy security reasons.
Lauri Myllyvirta:
[17:25] For sure, I think there are both synergies and tensions very clearly. So one thing is electrification very clearly hits both targets at the same time. So electrification enables the industrial sector, building sector, transport sector to become ... And much less carbon intensive because electricity keeps getting cleaner, the fuels don’t. But it’s also something that the coal industry likes because it enables coal-fired power plants to supply more to those sectors instead of oil and gas. So then the coal industry was very heavily promoting this line that coal-fired power generation can keep growing while emissions peak and start to decline. And electrification is also the enabler of that. And of course, clean energy is a part of China’s domestic energy portfolio. Very clearly, they have very strong domestic supply chains for solar, for wind, for nuclear, for batteries, for all the key technologies. So it’s very much something that is secure domestic energy in every sense. But then the tension is with coal-fired power generation, which also overall China imports about 10% of the coal that it uses.
Lauri Myllyvirta:
[18:48] But for some provinces, it’s a lot more, especially on the coast. And so there has been tension here. So the long-term plan has been to move the coal industry inland, where it can use domestic coal. It’s very hard for Chinese coal mines far inland to compete with imported coal on the coast. But so then during the previous five years, many of the coastal provinces built very large amounts of new coal-fired power plants because of concerns about another aspect of energy security, which is whether you have enough capacity to meet electricity demand during times of peak demand. And that increased the structural reliance on imported coal. So just as any other policymakers, they’re juggling multiple emergencies and perceived emergencies and priorities at the same time and making a lot of compromises, some of them short term and so on.
Robinson Meyer:
[21:17] So let’s get into this question about the Chinese emissions target. So China, I think, has a reputation internationally for always meeting its emission targets and for setting emissions targets that it can hit. And when it’s sometimes conservative in its targets, there’s a sense that, OK, well, it is being conservative, but that’s because it’s very focused on setting targets that it can hit. But it sounds like in the run up to this report, it became clear that China was not going to hit its 2030 target under the Paris Agreement. And so As you write, it basically revised its own accounting metric. Can you just describe what happened there and how it was able to change its accounting midstream, basically?
Lauri Myllyvirta:
[22:02] I’ll start with what is known. China has been reporting on reduction in carbon intensity. Carbon intensity is the amount of CO2 per unit of GDP. And so if emissions stay flat, GDP goes up by 5%, carbon intensity falls by a bit less than 5% in a year.
Robinson Meyer:
[22:21] My understanding, and maybe this is wrong, is that up until 2030, the bulk of its emissions targets under the Paris Agreement, its nationally determined contributions are phrased in the terms of carbon intensity, not in the terms of like, here’s what our national emissions target is going to be. They were primarily talking about our big target is reducing the carbon intensity of our economy, rather than hitting some kind of tons per year goal that the U.S. and Europe and a lot of other countries adopted.
Lauri Myllyvirta:
[22:50] For sure. So for 2020 and 2030, China has had a few different targets, but the one that is most closely related to emissions, and in that sense, the cornerstone target is carbon intensity. And so until 2020, China was overachieving that target. But then during the COVID and Zero COVID period, China went through very ...
Lauri Myllyvirta:
[23:18] energy-intensity, a period of very energy-intensive and carbon-intensive period of growth with the service industries and other less energy-intensive industries were obviously not doing great. So that meant that carbon intensity started falling much more slowly, CO2 emissions grew faster during that period, at least according to the numbers that China had reported. So they had been reporting carbon intensity reductions every year. And if you take the numbers from 2021 to 2025 they add up to a reduction of about 12% in China’s carbon intensity over that five-year period and the target was 18% and that’s what they needed to get on track to or stay on track to the 2030 carbon intensity target and so that means that if you have a shortfall of six percentage points during these five years then the target for the next five years becomes very demanding.
Lauri Myllyvirta:
[24:18] But so then along comes this new five year plan. And it says that we achieved a reduction of 17.7% instead of the 12-point-something percent. So that is a huge revision. If you rephrase that in emission terms, it means that earlier China had said that their emissions over this five year period had increased about 13% in absolute terms. And now they say the increase was only 6%. So half of the emission growth disappeared. So this is what we know for a fact. The less clear part is what is this revision based on?
Lauri Myllyvirta:
[24:59] The only indication of that is the latest annual report that discloses this carbon intensity reduction had a footnote saying that carbon intensity means carbon emissions per unit of GDP from energy activities and industrial processes. Whereas earlier, there had been no definition. But if you work with China’s numbers, the only way to make the earlier numbers add is that it’s only CO2 emissions from fossil fuels. So they included industrial processes and quite clearly excluded so-called non-energy use of energy, of fossil fuels, which means fossil fuels being used as a feedstock for producing things like plastics or fertilizer or whatnot. And so the big question here is non-energy use went up massively over the five-year period. We know that that’s all the culture chemicals and oil-based petrochemicals growth which has been massive but.
Lauri Myllyvirta:
[26:05] Did the amount of carbon that is stored in the products from this industry really increase so much that it justifies this massive revision to the numbers? And I’ve been trying to calculate that in a number of different ways, and I don’t think there’s a way to make this up. So especially with coal-based chemical production, much less than half of the carbon in the coal ends up in the products and the less ends up as process emissions from the coal to chemicals process. And so I think the most likely explanation here is that there are major gaps in the process emissions data from this industry and those process emissions are substantially underreported. But this is, again, this is just my best attempt at parsing the picture together from very partial information. So the really important thing is to push for and get clarification on this revision and what it means for the integrity of China’s carbon accounting for the future.
Robinson Meyer:
[27:16] How does this fit with other information that we have about Chinese emissions? Because my sense was that outside assessments of Chinese emissions, like yours, for instance, show that China’s greenhouse gas emissions have plateaued over the past two years. So how does that fit in with these carbon intensity data?
Lauri Myllyvirta:
[27:36] So my estimates and those by others such as global carbon projects have shown a plateauing of emissions starting from early 2024, but this is about the period from 2020 to 2025. And those other assessments, as well as China’s earlier annual reporting, showed a very sharp increase from 2020 to 2023. One thing that I want to just point out is that I think for most people, if you hear 2020 being used as the base year, you assume that was a massive dip because of COVID, but it was not the case in China. In China, CO2 emissions increased year on year in 2020.
Robinson Meyer:
[28:18] What it sounds like you’re describing very diplomatically is China misrepresenting or not fully reporting its emissions and air pollution data for politically convenient reasons. I remember there was some of this back during the days of, say, like, really bad Beijing air pollution. But have we seen China distort and or misrepresent or kind of edit its own carbon accounting in climate pollution data before?
Lauri Myllyvirta:
[28:48] Not in this way. So there was, in fact, there was a big revision to coal consumption data, a decade ago, but that was to correct earlier underreporting. And it was a massive increase in reported numbers back then. So there have been adjustments. And I try to be balanced about this because on one hand, we do want process emissions to be included. We do want accounting that is truthful and with the massive increase in non-energy use of fossil fuels you know i can see see that this change is something that you would want to make that just the earlier calculation of how much carbon is contained in all the fossil fuels that you used that was getting out of date because of the massive non-energy use but i’m working with very partial information parsing it together. So I just don’t want to say that I can say with 100% certainty that it’s wrong. But clearly, it was a very politically convenient revision. So yeah, that’s just one to lay out this full picture.
Robinson Meyer:
[29:56] I mean, I guess the kind of broader question is like, China has a reputation for setting these very conservative climate targets, and then meeting them.
Lauri Myllyvirta:
[30:04] Yeah, well, so one thing that’s important to point out is that they did not claim that they met it to the dot. So a very small, small shortfall, but still a shortfall compared with the target.
Robinson Meyer:
[30:16] Well, I guess my kind of question here is that they have this reputation for always meeting the fairly conservative climate targets they set. And I think to some degree, this allows China to play to a different standard than other countries, which are really encouraged to set very ambitious climate targets, and then maybe not judged as harshly when they don’t meet them. But it’s always kind of characterizes the run up to UN events is that there’s a lot of elicitations of lots of countries to set very, very ambitious targets. And then when China comes out with a not so ambitious target. To some degree, they have the world’s largest clean energy industry. And so people are inclined to be merciful anyway. But the sense is, well, China always sets these very conservative targets, but then it meets them. And that and it attaches a high level of international credibility to its ability to meet these targets. Is that … does this episode, which I realize is a singular episode, but does it suggest that like that is no longer a good way to understand China’s emissions targets or that that system could be breaking down and China’s leadership is willing to sacrifice emissions targets for the sake of energy security? Because it sounds like a lot of this emerges from the coal to chemicals industry, the kind of demand for domestic energy security and secure domestic production and feedstock inputs.
Lauri Myllyvirta:
[31:33] And one thing that’s very clear is that there was no last-minute push to make up for the shortfall.
Lauri Myllyvirta:
[31:43] So, well, of course, you could say that maybe the major clean energy build-out could be seen as that. But comparing with earlier, back in 2010, China, in fact, missed its energy intensity goal. And there was a very strong last minute push to reduce energy intensity and get as close to the target as possible and then in 2017 China was badly off track to the ambitious air quality targets that had been set for that year in the first national air pollution action plan and there was a very aggressive campaign especially on small-scale coal use that in fact succeeded in meeting those targets but that episode especially gave a very bad name to these what are known as campaign style efforts to meet targets because what happened was that a lot of small-scale coal stoves and boilers were eliminated and the infrastructure to replace them with gas fired heating was not there when the winter started so a lot of people were very very cold for some time and that really rightfully put those kinds of measures out of favor but so then back in.
Lauri Myllyvirta:
[33:06] 2022 or 2023, there was the midway review of the five-year plan. And it said that carbon intensity is badly off track. The state council issued an action plan to get back on track and it didn’t have a whole lot of traction. It didn’t even set annual targets that would have enabled the country to get back on track and so on. So yeah, certainly during this five-year period, Maybe there has been a sense that because of COVID and whatnot, it was a force majeure situation, but there hasn’t been an emphasis on meeting those targets, to be sure.
Robinson Meyer:
[33:44] So we’ll release this episode tomorrow. We don’t know exactly what’s going to happen in the next 24 hours in Iran. But when we’re recording this, the Strait of Hormuz remains closed and basically the world has lost 20% of global oil capacity and a fair amount of global liquefied natural gas capacity, as well as many, many chemical inputs and other chemical commodities, including fertilizer and aluminum. How has China, a lot of the oil that comes out of the Strait of Hormuz goes to Asia and specifically goes to China. And the price effects of the loss of that oil are global, but the actual supply constraints are going to first hit Asia. How has China responded to the Strait of Hormuz closure so far?
Lauri Myllyvirta:
[34:27] So the main thing that China has done is ban the exports of refined oil products. The country has massive reserves, massive inventories of oil and somewhat regulated fuel prices. They’re indexed to global prices with a bit of discretion. And so that at least delays the way that global prices filter to Chinese fuel prices and it gives the policymakers control over that. So in that sense, if this ends up being a relatively temporary situation, I think the Chinese market could be fairly sheltered from it. But of course, there’s the economic impact, for example, on those chemical industries.
Lauri Myllyvirta:
[35:15] Overall, I think this kind of a crisis is exactly what Chinese planners have had in their minds for a long time. And so there was a refocusing on energy security during Trump’s first term. There was a speech by Li Keqiang, the then premier in 2019, where he brought energy security very strongly back to the frame. And that was, far as anyone can tell, that was because of the perception of a much more hostile geopolitical environment. And because of that, the risk of the Straits of Malacca. So the other strait that much of the oil to China passes through being blocked. So everything that has happened in the past months is very much validating and reinforcing the energy security approach that Chinese planners have taken. The other event that I think is significant in that was the seizure of Russian flag tankers in high seas on the Atlantic by the U.S.
Robinson Meyer:
[36:18] This is what happened a few weeks after the Venezuela invasion, right? The U.S. Pursued these Russian-flagged tankers carrying, I think, Venezuelan oil. Out of the Gulf of Mexico into basically the open Atlantic Ocean and ultimately did board them. And there was some question about whether they were Russian-flagged at the beginning of the pursuit. At the beginning of the pursuit, but they were Russian-flagged by the end of the pursuit, but it represented kind of the U.S. Navy’s willingness to interdict, you know, seaborne fossil fuels.
Lauri Myllyvirta:
[36:47] Exactly. So all of this is going to reinforce the approach of reducing reliance on seaborne fossil fuels. And of course, things like seeing tankers hit by cheap drones, and so on.
Lauri Myllyvirta:
[37:01] I think anyone who buys seaborne fuels should be paying attention. And I’m sure Chinese planners are.
Robinson Meyer:
[37:07] It seems to me that when you look at the kind of whole picture, what emerges is that you can understand basically, a lot of Chinese energy policy, I’m not going to say all of it, but you You can understand a lot of Chinese energy policy at the absolute highest level out of anxiety about the seaborne fossil fuel trade and anxiety about domestic air pollution in big cities. Follow those trends. You get a big inland coal industry, you get a willingness to rely on coal, you get a willingness to electrify, you also get, of course, these huge clean energy industry. Am I kind of right to draw the lines from those two points? Absolutely.
Lauri Myllyvirta:
[37:47] So the third one that I would add is, I think there has been a very clear, longstanding determination that clean energy technologies are a key part of the technological and an economic and energy future. And so wanting to make sure that China has technological leadership, market leadership in those technologies has been one long-running thread in this as well. But I think most of the misunderstandings about China’s energy policy just comes from wanting to force it into a mold that fits some kind of an argument that people are making about things other than China. So you want China to be the clean energy champion, a global savior that you can put on a podium or want them to be the bad guys who always lie and always can be used as to say that it doesn’t matter what we do because China is always going to be doing something terrible. So if you try to approach things from one of those perspectives and try to make sense of it, then of course they don’t make sense. But if you make an effort exactly as you did to think about what are the actual motivations and aims, then surprisingly a lot of things start to make sense.
Robinson Meyer:
[38:58] It kind of all falls into place. I mean, what do you think that Western countries in Europe and North America can learn from the Chinese approach? Because it seems to me that the U.S., certainly the Biden administration’s approach to climate policy would have been very different if it followed a more Chinese-style approach. I think the same is true of the European Green Deal. But it also seems to me that goals that Western liberals in the kind of broadest sense attached to climate policy would not. Be as achievable if we adopted this same security-minded approach. It would be a much more paranoid world uh you are yourself a european so like how do you understand what we should learn as a west to the degree that that’s a useful category from China versus what do you think is kind of worth discarding or you hope that China eventually could move past.
Lauri Myllyvirta:
[39:54] That’s a great question. Of course the China system is special in a lot of ways but some of the policies that have been used to to roll out clean energy are very smart and could work just as well in many other systems. So if you think about this layout of the gigantic clean energy bases that China has in the western and northern
Lauri Myllyvirta:
[40:17] deserts, abandoned coal mines, offshore wind, all of these things designating large areas where, permitting is made easy, where land conflicts are less, and planning transmission and planning clean energy at an enormous scale around those make a lot of sense. And then on the other side, the rod of distributed solar, China used a model of whole county solar. So the idea is that you have a district or a county that sets a target of X% of rooftops covered by solar. And then you do centralized procurement, centralized contracting with the grid operator. And that drives down costs by quite a bit when you can just have a bunch of installers who are working their way from one building to the next and so on but it also creates this effect of we know that the most important predictor of whether people put on a solar panel is whether their neighbor has one EVs as well so the point is that i think people look too much at the differences between the Chinese system and other systems of government and dismiss those things where China has innovated and come up with ways to overcome obstacles that are exactly the same in other places in the world.
Robinson Meyer:
[41:42] When China does something like declare a clean energy base in a rural area or set a country, a province-wide target for solar, that’s also a domestic industrial policy. And China has a very big domestic solar industry, has a very big domestic manufacturing industry in basically all industries. And so when it sets a target or when it eases permitting, the domestic political economy is like very friendly to it. It strikes me because it has manufacturers who are always looking for a place to put their manufactured goods, to sell their manufactured goods. And I guess my question is like, how much of Chinese clean energy policy or how much of these beneficial policies, I’m fixating on the differences, as you said, I shouldn’t do, but I’m going to do it, is like how much of what it’s able to do in terms of deployment is downstream of its consumer market and manufacturing base. And is that something we should learn from too? I mean, should we, should Europe or North America be trying to encourage some, a much larger manufacturing sector than maybe we have now because while it could be kind of globally duplicative, it actually allows for a lot of implementation and infrastructure level policy and expertise to build up that then helps you when you’re kind of structuring the engineering of a society or the infrastructure in a society.
Lauri Myllyvirta:
[43:03] I’m all for policies that diversify the supply of clean energy technologies and that strengthen the political economy as well. I think that’s certainly a big factor. And that is a factor in China. So for example, provinces do have the motivation to deploy very clear in the EV industry that it’s been the provinces even more than the central government creating whole markets for their car manufacturers and so on but at the same time if you look at europe we have the biggest wind industry winter wind power manufacturing industry in the non-chinese market and that hasn’t meant that we’ve done very well in in deploying wind with with underperformed and that we have a big very significant auto industry but we’ve certainly failed to transform that for the age of electricity.
Lauri Myllyvirta:
[44:00] So it doesn’t always translate that way. Arguably, we’ve been a lot better at deploying solar where there’s less of a European manufacturing base. But so I do think that if we do get those policies in place, that will help. And also, I do want to remind people that there are significant manufacturers of cleantech outside of China, whether it’s Japanese and Korean battery makers or European producers of wind turbines, heat pumps, air frisers, so on. So the first step is making sure that those producers are able to stay in business and expand and have a strong market. And we are also a significant and a surplus producer of EVs and so on. And then the next step is thinking about the harder questions like solar where China does have a very significant role.
Robinson Meyer:
[44:54] When we talk about these massive clean industrial bases, or I was just thinking when we talk about those, because there’s this, we’ll stick it in the show notes, but there’s this amazing map in your post about the five-year plan, which shows the areas where China is trying to encourage clean energy in the country’s interior. And then these giant arrows kind of representing its high voltage grid, where it’s going to move this energy to the cities, generating cheap energy in the rural interior and sending it to cities is very GDP maximizing. It’s very pro-city. How much of the policies that we like or that are kind of praised internationally by an international audience arise from maybe a system that is much more willing to... Adopt, let’s say, policy that’s good for cities and urban areas, or that relies on a system that kind of is willing to uplift urban agglomerations and urbanization, as opposed to say, I think of the U.S. example here as the kind of classic counterexample where rural areas have far more power in our political system than cities do.
Lauri Myllyvirta:
[46:03] Now, right, I would actually say that that pull is the other way around. So there is a big regional economic policy component to moving all kinds of industries, often extractive industries, coal, wind, solar, into the west and into the north. So because the coastal urban areas are the ones that pulled ahead of the rest of the country economically. And even these long distance transmission lines, of course, they’re sold as it helps reduce air pollution in the east and so on but it’s really the coastal provinces don’t like these they have to be pushed into accepting this supply of electricity because they would rather generate within the province to grab that bit of gdp and tax revenue and everything else from that production so yeah the central government policy on this is more focused on spreading the economic gains towards the interior and the less well-off places.
Robinson Meyer:
[47:09] Wow, that’s so interesting. Okay, we have to leave it there. But Lauri Myllyvirta, thanks so much for joining us here on Schipski, and we’ll talk again soon.
Lauri Myllyvirta:
[47:17] Thank you so much.
Robinson Meyer:
[47:22] That will do it for us today. If you enjoyed this episode of Shift Key, please leave us a review on your favorite podcast app or just send this episode to a friend who you think might enjoy it. You can find me on BlueSky, LinkedIn, X, basically any social network. There’s only one of me so far, so you can find me there. We’ll be back next week with a new episode of Shift Key. Enjoy your weekend. Until then, Shift Key is a production of Heatmap News. Our editors are Jillian Goodman and Nico Lauricella. Multimedia editing and audio engineering is by Jacob Lambert and by Nick Woodbury. Our music is by Adam Kromelow. Thanks so much for listening. See you next week.
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On copper prices, nuclear’s jellyfish woes, and Leo DiCaprio’s Chilean NIMBYism
Current conditions: The death toll from Colombia’s earthquake has risen beyond 250 • A severe thunderstorm flipped a car in Columbus, Ohio, as a large system swept across the Midwest • A partial solar eclipse is set to occur the Northeast.

David Crowley, a moderate Democrat and local official in Milwaukee, narrowly defeated Francesca Hong, a leftist state lawmaker and former ramen chef, in the Democratic gubernatorial primary in Wisconsin last night. The race marked one of the most significant tests of Democratic voters’ willingness to elect a member of the ascendant Democratic Socialists of America, now the most popular socialist group in U.S. history. Her campaign promised to make childcare and school lunches free, repeal anti-union laws, and give renters more protections against eviction. She also pitched what she called her “control-alt-delete” plan to eliminate tax credits for data centers and put a statewide moratorium on permits for new artificial intelligence facilities.
Ahead of Tuesday’s primary, the AI developers Vantage, Oracle, and OpenAI announced a $60,000 community investment in Port Washington, which my colleague Jael Holzman described as “the most controversial data center development area in the state.”
Just last week, the Trump administration agreed to pay the energy giant RWE more than $1.2 billion to abandon an offshore wind project, the latest in a series of deals in which taxpayers hand over billions to not receive new sources of clean electricity they badly need. On Tuesday, Senators Alex Padilla, the California Democrat, and Angus King, the independent from Maine, introduced a bill that would give companies that reject Trump’s payouts an expedited route to more development. “The Trump Administration is doing everything it can to kill California’s offshore wind future, handing energy companies billions of taxpayer dollars to walk away from projects that would have powered millions of homes,” Padilla said in a press release. “This bill makes sure their destructive approach doesn’t waste what’s already been invested so we can get these leases back to work, create the jobs Trump killed, and keep energy bills low for working families instead of letting his war on renewables cost Californians even more.”
The bill has one potential flaw, other than the fact that Republicans are unlikely to pass it and President Donald Trump is even less likely to sign it. That, as my colleague Robinson Meyer wrote this week, is that the roughly $4 billion in payouts so far went to projects that were “already dead or dying.” The money spent, in other words, is “for nothing.”
Please read the following two sentences in the tone of the famous scene of Tony Soprano defending Christopher Columbus: In this newsletter, Ea-nāṣir, the Mesopotamian copper merchant from Bronze Age-era Ur whose stone-carved complaints about a subpar metal shipment remain readable millennia later, is a hero. End of story! Why, you might ask? Because we are once again living through an age where copper, the basic building block of all things electric, is in high demand. Copper soared back to within half a cent of its record high Tuesday of nearly $14,000 per metric ton after an outage at a major smelter in Indonesia rattled global prices, Mining.com reported.
The fight over North America’s only major cobalt refinery, meanwhile, is heating up. The mining giant Glencore made a bid for control of Sherritt International, which has taken a beating from U.S. sanctions due to its 50% stake in Moa, a joint venture with the Cuban government. The joint venture’s assets include the Canadian refinery and Moa nickel-cobalt mine in Cuba. The Glencore-backed consortium is up against Gillon Capital, the family office of Ray Washburne, a Republican fundraiser and former Trump official, according to the Financial Times.
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Weeks after Europe’s latest heat wave forced inland nuclear stations to pare down output for lack of cooling water in the continent’s rivers, a “massive influx” of jellyfish has forced France’s EDF to shut down three units at its Gravelines nuclear station and cut power from a fourth. That’s taken at least 3.2 gigawatts of capacity offline, Bloomberg reported, right as temperatures are expected to surpass 104 degrees Fahrenheit in the coming days. The unusually hot temperatures off France’s shores have encouraged jellyfish populations to “bloom,” clogging the pumping stations through which coastal nuclear plants like Gravelines pull in cooling water.
In Egypt, meanwhile, construction crews working on the country’s first nuclear station hit a critical milestone. The containment vessel for the Russian-designed El Dabaa plant’s first unit is nearly completed, according to World Nuclear News.
Digging deep enough into the bedrock around New York City to tap into lava-hot rocks for electricity production is probably still years away, despite the progress that next-generation geothermal companies such as Fervo Energy have recently made. But thermal networks that maintain a steady environment year-round by circulating air at a constant temperature are increasingly popular ways for New Yorkers in private homes outside the city to stay warm in winter and cool in summer. Now the city itself is seeing whether a large-scale version could work for the subway system and municipal buildings. A study is set to begin soon into whether a thermal energy network could be built along subway routes to capture, store, and redirect excess heat that accumulates in the Brooklyn Bridge-City Hall and Chambers Street station complex to municipal buildings above ground. “Radiant cooling technology will absorb heat from the subway platforms and transfer it to geothermal boreholes drilled beneath Chambers Street,” reporter Carlo Cariaga wrote for Think Geo Energy. “This excess heat will then be stored underground until it can be used for supply to nearby municipal buildings during winter.” The contract for the feasibility study is due to be awarded in the fall, with work scheduled to start in early 2027.
“It seems like it’s a good place to test geothermal solutions because it sounds like there is a part of the tracks that isn’t being used, so they don’t have to stop service,” Jack Klein, the citizen researcher who conducted his own gonzo Subway heat study last year, told my colleague Jeva Lange this week.
Leonardo DiCaprio has long been a major donor to environmental causes. But rarely has the actor taken as clear a stance against green development if it comes at any ecological cost as this. On Tuesday, Bloomberg reported that the Oscar winner had told his nearly 60 million Instagram followers that fewer than 1,000 Pehuenche spiny-chest frogs remain in the wild, and that construction of the proposed Chile-Argentina transmission line threatens the amphibians’ habitat. “Conservationists are not asking for the transmission project to be stopped,” the celebrity wrote in the post over the weekend. “They are asking for it to be built where it does not put a Critically Endangered species at even greater risk.”
Rob checks in on this season’s supercharged ocean temperatures with climate researcher Zeke Hausfather.
Every few years, the Pacific Ocean’s surface waters become especially warm near the equator, a climatic phenomenon known as El Niño.
El Niño is a normal part of the climate system, but even in a normal year, it can trigger extreme weather around the world. Forecasters are worried that the current El Niño — which just began a few weeks ago — is going to be anything but normal. Models suggest that we could soon see the hottest El Niño ever measured, with unpredictable and catastrophic effects for ecosystems and societies around the world.
What does that mean? And why does this El Niño look so bad? On this episode of Shift Key, Rob is joined by Zeke Hausfather, a climate research lead at Stripe and a research scientist at Berkeley Earth. They discuss what forecast models are saying about this El Niño, why it gives us a glance at the future, and whether climate change itself is accelerating.
Shift Key is hosted by Robinson Meyer, the founding executive editor of Heatmap News.
Subscribe to “Shift Key” and find this episode on Apple Podcasts, Spotify, Amazon, or wherever you get your podcasts.
You can also add the show’s RSS feed to your podcast app to follow us directly.
Here is an excerpt from their conversation:
Robinson Meyer: How much, at this point, are we in an El Niño that is record-breaking? Like, how much do we see in observations, physical observations of the ocean or the atmosphere and the rest of the climate system, and how much do we think from the models that it is going to get even hotter?
Zeke Hausfather: So the way that we track the strength of an El Niño — there’s a few different ways to track it. But the most common one is from this particular region of the tropical Pacific called the Niño 3.4 region, which is sort of like about a third of the way into the Pacific off the coast of Chile, right around the equator. And that’s where this tongue of warm water forms during El Niño events. That’s sort of the characteristic signal of El Niños. And temperatures in that region, as of today, are at 2.8 degrees centigrade above normal, normal meaning the average of the last 30 years. So it’s sort of a sliding window that tries to remove some of the human-caused warming.
Robinson Meyer: Are we comparing temperatures from that region to another region? Or they’re just in that region two or more degrees above normal?
Zeke Hausfather: So it’s a good question. The traditional way that El Niño has been defined is to just compare that region to itself, but with a 30-year moving average applied to remove the effects of human-caused warming. There is another metric that was introduced by NOAA last year called the Relative El Niño Index, which is a variant where you sort of subtract out the average over the tropical ocean as a whole from that region, so you’re looking at the difference between that region and the rest of the tropics.
There’s pros and cons of that approach. Arguably, it removes the human warming signal a bit better, but it also can overly penalize really strong El Niño events that reach outside of that region because they start warming the whole tropics. So anyway, the details are technical, but the point on the observations is that we’re already seeing a very strong event occurring there today. You know, temperatures as of today, when we’re recording, August 10, are 2.8C above normal. To put that in perspective, the strongest ever anomalies we’ve recorded, at least daily in the satellite record since the 1980 or so, were in 2015, 2016, and those were about 3.1 degrees above normal. And so as of today, by itself, it would be the third strongest El Niño signal ever recorded in that region.
But what’s different is that El Niño almost always peaks near the end of the year. So if you look at all the El Niño events on record, there’s been one or two that have peaked in October, but the vast majority peak in November or December, and a couple as late as January. It’s a very persistent pattern of these events. And so the fact that it’s only the beginning of August now and we’re already at this extremely high level, we’re essentially running two to three months ahead of any other El Niño on record in terms of how quickly it’s developing, which is one of the reasons why we’re increasingly convinced that this is going to be a record-setting event. It’s going to blow any event we’ve seen previously out of the water. And if you look at the latest models that came out this morning, actually, it’s good timing. They’re predicting a peak of around 4C in the Niño 3.4 region, which will be, you know, more than a degree above the previous record and could end up being the strongest El Niño in 500 or 1,000 years. We don’t have great proxy estimates going back, but, it certainly is something well outside of anything we’ve seen since records began in 1850.
Robinson Meyer: The swimmer Katie Ledecky swims a race sometimes in the Olympics and she’ll be out swimming and then behind her there’s a computer-generated line which is the current world record, and she’s way out in front of the current world record, and you’re watching her and then she does she turns around in the pool and then the world record is behind her. That is the current El Niño. This is the Katie Ledecky-style El Niño.
You can find a full transcript of the episode here.
Mentioned:
NOAA’s El Niño page and the relative El Niño index
An Assessment of Earth's Climate Sensitivity Using Multiple Lines of Evidence, the 2020 paper where Zeke was a coauthor
Zeke’s blog post on AI emissions: The real energy use of agentic AI
John Bistline’s post on AI emissions at Watershed
Heatmap’s coverage of AI emissions: A New Guesstimate for Corporate AI Emissions
This episode of Shift Key is sponsored by ...
Discover the Yale Clean and Equitable Energy Development online certificate program at the Yale Center for Business and the Environment. In this fully online, 5-month program, you’ll learn from leading experts, develop practical skills, and grow a powerful network. Visit cbey.yale.edu to learn more and apply.
Music for Shift Key is by Adam Kromelow.
This transcript has been automatically generated.
Subscribe to “Shift Key” and find this episode on Apple Podcasts, Spotify, Amazon, or wherever you get your podcasts.
You can also add the show’s RSS feed to your podcast app to follow us directly.
Robinson Meyer:
Hello, it’s Wednesday, August 12, and the Pacific Ocean is officially in El Niño. According to the National Oceanic and Atmospheric Administration, sea surface temperatures in the key region of the Pacific are now above average, and the agency expects they’ll remain that way through early spring 2027. Now, even a normal El Niño can be a big deal. They can cause very wet winters in California, huge rainfall events in South America, and droughts or even famines in parts of Africa and Asia.
Robinson Meyer:
But if you’ve been paying attention, you know that this El Niño seems like it’s not going to be normal. It seems like it will be a super El Niño. Forecasters are now warning we could see the largest El Niño in years or decades, if not in a century or more. The last time we had a super El Niño event in 2015 and 2016, it caused almost $4 trillion in global economic damages. This one now seems like it could be even bigger. So I wanted to learn more about what might be coming down the pike, why we think this El Niño, even though it hasn’t happened yet, or has only just begun, could be so big and what it could all mean. And we have a great guest. Zeke Hausfather is a climate research lead at Stripe and a research scientist at Berkeley Earth. He’s also an IPCC author. He’s a climate scientist with a strong interest in observational temperature records, climate modeling, mitigation and emission scenarios, and carbon removal. He’s kind of working on all sides of the climate problem at the same time, which is why I always enjoy talking to him. And I can’t believe we’ve never had him on Shift Key before. On this show, we talk about why we think this El Niño will be so big, why it will be a kind of preview of sorts of the climate of the 2030s, and whether climate change now seems to be accelerating and getting worse. I’m Robinson Meyer, the founding executive editor of Heatmap News, and it’s all coming up on Shift Key. Zeke Hausfather, welcome to Shift Key.
Zeke Hausfather:
Thanks, Rob. Great to be on.
Robinson Meyer:
One reason I always enjoy talking to you is because you’re at this nexus of, let’s say, climate science and the physical systems and physical processes that happen in the world and mitigation and carbon removal and decarbonization and the various processes we need to master to tackle climate change. You’ve been tracking recently a particularly worrying set of developments around this year’s El Niño. And I think over the past few weeks, it’s gone from something watching you write and share what the models are saying, what we can know about the coming El Niño, has gone from making me think that it was, oh, that’s kind of interesting to, wow, this is a massive story that’s unfolding in front of us that’s going to shape this. Not only the next year of how we talk about weather and climate, but really the coming year of global events. So I want to just start by asking you, what do we know about this year’s coming Monster El Niño, as it has recently been described? And how has it developed over the past few weeks and months?
Zeke Hausfather:
Yeah, so it’s funny you call it a Monster El Niño. We’ve traditionally said super El Niño but this is going to be so far beyond a super El Niño if the models are right that we sort of need a new term for it i prefer monster to godzilla El Niño which is the other one thrown around but in terms of this year’s El Niño so we knew an El Niño was coming by late 2025 but we didn’t know how strong and so there’s a set of different dynamical models this year some of them are actual climate models some of them are you know more simple sort of adapted weather models But there’s about 14 or so different groups around the world that publish these sort of dynamical models of El Niño behavior. And so we knew that there was something in the pipeline. But at least initially, you know, circa January, February, it looked like it would be a pretty moderate event, you know, something maybe akin to... What we saw in 2010 may be enough by itself to drive a record warm year. And we’ll talk about the relationship later between El Niño and global temperatures, but not something that would be record setting by any stretch of the imagination. But by April or so of this year, we really started getting a big shift in the models. Back then, they showed something that could potentially tie 2015-2016 as the strongest El Niño event on record. Actually tie both 2015-2016 and the sort of storied El Niño of 1877-1878,
Zeke Hausfather:
Which is a particularly disastrous event in the early part of the record. But with every month that has come since, the models have been projecting higher and higher and higher estimates for this El Niño event. And the observations have been consistently overshooting what the models previously had projected. So, it’s not just the models that are going up, the observations are also skyrocketing and leaving the previous model projections in the dust. And there’s this thing in El Niño forecasting called the spring predictability barrier, which essentially is the fact that we’re just not very accurate at predicting El Niño during the spring. And so for a while there, everyone was kind of debating, like, is this another, you know, because there have been some historical cases where particularly individual models have gotten things really wrong in the spring. They’ve said the super strong El Niño event is coming, and it never came for one reason or another. The westerly wind bursts didn’t happen, or there’s changing patterns of circulation that led to the El Niño not developing. But now we’re well out of the spring predictability barrier, right? And we’ve seen observations already go into record territories. In fact, as of today, we are currently in the third strongest El Niño event ever recorded, maybe fourth if you go back to the 1800s.
Robinson Meyer:
Well, this actually gets to a key follow-up, which is how much at this point are we in an El Niño that is record-breaking? Like how much do we see in observations, physical observations of the ocean or the atmosphere and the rest of the climate system? And how much do we think from the models that it is going to get even hotter?
Zeke Hausfather:
So the way that we track the strength of an El Niño, there’s a few different ways to track it. But the most common one is from this particular region of the tropical Pacific called the Nino 3.4 region, which is sort of like about a third of the way into the Pacific off the coast of Chile, right around the equator. And that’s where this sort of tongue of warm water forms during El Niño events. That’s sort of the characteristic signal of El Niños. And temperatures in that region, as of today, are at 2.8 degrees centigrade above normal, normal meaning the average of the last 30 years. So it’s sort of a sliding window that tries to remove some of the human-caused warming.
Robinson Meyer:
Are we comparing temperatures from that region to another region, or they’re just in that region two or more degrees above normal?
Zeke Hausfather:
So it’s a good question. The traditional way that El Niño has been defined is to just compare that region to itself, but with a sort of 30-year moving average applied to remove the effects of human-caused warming. There is another metric that was introduced by NOAA last year called the relative El Niño index, which is a variant where you sort of subtract out the average over the tropical ocean as a whole from that region. So you’re sort of looking at the difference between that region and the rest of the tropics. There’s pros and cons of that approach. Arguably, it removes the human warming signal a bit better, but it also can overly penalize really strong El Niño events. That reach outside of that region because they start warming the whole tropics. So anyway, the details are technical, but the point on the observations is that we’re already seeing a very strong event occurring there today. You know, temperatures as of today, when we’re recording, August 10, are 2.8C above normal. To put that in perspective, the strongest ever anomalies we’ve recorded, at least daily in the satellite record since the 1980 or so, were in 2015, 2016 …
Zeke Hausfather:
And those were about 3.1 degrees above normal. And so as of today, by itself, it would be the third strongest El Niño signal ever recorded in that region. But what’s different is that El Niño almost always peaks near the end of the year. So if you look at all the El Niño events on record, you know, there’s been one or two that have peaked in October, but the vast majority peak in November or December and a couple as late as January. You know, it’s a very persistent pattern of these events. And so the fact that it’s only the beginning of August now and we’re already at this extremely high level, we’re essentially running two to three months ahead of any other El Niño on record in terms of how quickly it’s developing. Which is one of the reasons why we’re increasingly convinced that this is going to be a record setting event. It’s going to blow, you know, any event we’ve seen previously out of the water. And if you look at the latest models that came out this morning, actually, it’s good timing. They’re predicting a peak of around 4C in the Niño 3.4 region, which will be, you know, more than a degree above the previous record and could end up being the strongest El Niño in, you know, 500 or a thousand years. We don’t have great proxy estimates going back, but, you know, it certainly is something well outside of anything we’ve seen since records began in 1850.
Robinson Meyer:
The swimmer Katie Ledecky swims a race sometimes in the Olympics and she’ll be out swimming and then behind her there’s like a there’s a computer generated line which is the current world record and she’s way out in front of the current world record and you’re watching her and then she does she turns around in the pool and then the world record is behind her that is the current El Niño this is the Katie Ledecky style El Niño. This seems like as good a juncture as any to ask what physically is an El Niño? We talk about it as an event. We talk about it as a kind of phenomenon that can develop within the global climate system. I think people know that it has to do with the temperature of the Pacific, but what actually is physically happening on the planet when an El Niño occurs?
Zeke Hausfather:
So El Niño is a natural phenomenon. There is arguably some contribution of climate change to El Niño intensity and frequency, but it’s a topic that’s pretty heavily debated and we can talk about that in more detail later. But El Niño itself happens every three to seven years. It’s got a sister event called La Nina, which is essentially the inverse of it, which is unusually cold temperatures in the tropical Pacific instead of warm temperatures. And El Niño is driven by a combination of wind and currents. You have what we call westerly wind bursts that are changing the ocean mixing behavior in the Pacific. And so during an El Niño event, effectively the ocean takes up less heat, and so the atmosphere ends up being warmer, or the ocean even releases some heat. During La Niña, which is the inverse, the ocean, the deeper ocean, I should say, takes up more heat, And so the surface is cool. And so interestingly enough, during strong El Niño events, you tend to have a smaller increase or even in some extreme cases, a loss of ocean heat content, whereas the surface temperatures where we all live end up being much warmer. And so, you know, this isn’t necessarily something that is being caused by humans, but it’s happening on top of human driven warming. And a lot of the year to year variability in global temperatures, which many folks are familiar with looking at, are driven by the sort of El Niño-La Niña cycle.
Robinson Meyer:
What is driving this shift within the model? If the models believe that it’s going to be very warm, then it seems like there are probably signals within the physical system that are pushing them to believe the sea surface will get even hotter than it is right now. And so what are those signals that they seem to be responding to as we understand them?
Zeke Hausfather:
So there’s a couple factors going on here, right? One is, as I mentioned earlier, observations are persistently running above what previous model runs predicted. So observations themselves of the El Niño region sea surface temperatures are persistently running above. Driving projections for a strong event. But we are not just measuring sea surface temperatures. We are also measuring meteorological conditions that are favorable to the sort of westerly wind bursts that drive growing El Niño strength. And we’re modeling and observing what’s happening in the ocean below the surface. And so there we see this sort of pulse of warm water coming from the Western Pacific into the Eastern Pacific and moving up toward the surface. And that warm water is quite warm. You know, some regions are nine degrees centigrade above normal in sort of the deeper ocean temperatures. And that’ll emerge at the surface off the coast of Chile and then spread out across the El Niño tongue into the sort of eastern and central Pacific in the tropics. And so just seeing this warm water moving under the surface toward the El Niño region gives us a little sneak peek to, you know, what’s going to emerge in the next few weeks.
Robinson Meyer:
Because when you see the satellite imagery. That’s thermal coated of an El Niño, it looks like this big tongue of warm, I mean, you just called it the El Niño tongue, but it looks like this big, you know, stalactite of warm water is jutting out into the ocean, and then fading into the kind of baseline temperature mix. But it looks like this big warm tongue that I guess is aligned with the equator or just below the equator or?
Zeke Hausfather:
It’s right around the equator. Yeah. And I think tongue is generally the term that’s and used by folks. But under the surface, the sort of opposite is happening, right? So at the surface, it’s spreading out from the coast of Chile to the west. But under the surface, you have water moving eastward, like warm water in the deeper ocean. And then that’s coming up at the surface in Chile and then spreading westward. And so it’s almost a circulation you could think of it as.
Robinson Meyer:
Let’s bracket out what this El Niño might mean. But what does an El Niño generally mean for the rest of the world. I realize it has lots of these local effects, but one thing I’ve observed, and even reading about El Niño and covering El Niño, is it seems to be both understood as maybe the biggest annual variable in the climate system. And that means it’s both strongly described and also there’s a lack of specificity sometimes about what exactly it will do or what a large El Niño means as opposed to a small El Niño.
Zeke Hausfather:
So what we can most directly say is what’s happening in the tropical Pacific. You know, we’re measuring the sea surface temperatures. There’s that tongue that is very visible. It stands like a sore thumb in any global temperature map during an El Niño event. But when you shift temperatures in the ocean, in the tropical Pacific, it has a whole bunch of teleconnections to the rest of the planetary climate. It’s going to move the jet stream around, it’s going to lead to changing precipitation patterns. And again, some of these are more deterministic than others.
Zeke Hausfather:
It increases the odds of things. It doesn’t necessarily always cause things. But the things that we do tend to see most often associated with El Niño events are or in the El Niño tongue itself,
Zeke Hausfather:
And directly around it, things get a lot wetter. So coastal Peru and Ecuador see a huge amount of rainfall, the Horn of Africa. There’s a few other areas that tend to get quite a bit wetter. But, and in some ways more importantly, the area around that tongue to the north and the south of it and to the west of it get a lot drier. And this is probably the single biggest and most problematic impact of El Niño is its effects on rainfall in those regions. So places like Indonesia and Southeast Asia, India, Southern Africa, Northern Amazon, Eastern Australia, they all tend to get quite a bit drier during El Niño events. And if you look at some of the bigger El Niño related catastrophes in history, like the,
Zeke Hausfather:
You know, mass deaths following the 1877-1878 El Niño event, when depending on what study you look at, somewhere between, you know, three and 50 million people died, that was largely due to crop failure associated with drought in those regions. So that’s the one I’d be most worried about. But, you know, there are also a bunch of other effects. So the western U.S. famously gets wetter during El Niño years. We tend to have mudslides here in California. Route 1 is probably going to get washed away more than usual. You know, we tend to have a bit warmer temperatures in the northern parts of the U.S. and northwest Canada. You know, the oceans as a whole get warmer. One thing that we’ve started seeing during El Niño events starting in 1997, 1987-1988 is these sort of globally widespread coral bleaching events. So the first time this was observed was in 97-98 during that El Niño event. And it’s since then become sort of a common occurrence every time we have a strong El Niño and even some summers when we don’t because the oceans have
Senator Martin Heinrich:
Gotten so hot.
Zeke Hausfather:
And so certainly this year, that’s something that a lot of people are concerned about in the winter in the tropics. There’s also a bunch of different effects on storms associated with changes in wind shear and circulation patterns. A very strong El Niño event will suppress Atlantic hurricanes. It’s one of the reasons that our forecast for Atlantic hurricanes has been cut in half already and might be cut significantly further. But it does tend to lead to more cyclones in the eastern Pacific. So cyclones that might hit Japan or Hawaii or China are going to become more common this year. And then globally, it tends to warm the climate as a whole. So a strong El Niño event tends to be associated with a boost in global temperatures of up to 0.4C for four or five months, and for the year as a whole of around 0.2C. Though this event, because it’s so unprecedented, might push it much further than that. There’s also a bit of a lag in time between when El Niño peaks in the tropical Pacific and when the global temperature effects have felt of about three to five months. So that’s one of the reasons why, even though El Niño is going to peak this year, it’s next year, 2027, that’s likely to be the record shattering one in terms of global temperatures. And that’s a pattern that we persistently see in, you know, 1997 was warm and 1998 was record shattering. 2015 was warm and 2016 was record shattering. It’s the year after El Niño peaks that we really see this big boost in temperatures.
Robinson Meyer:
And that’s because basically we’ve added all this anthropogenic CO2 to the atmosphere. We already know the Earth is kind of out of temperature balance where there’s more heat captured in the atmospheric system than there would be in a kind of a thermostatic way. And normally how that’s dealt with is that heat gets dumped into the ocean and water goes down to the ocean, the ocean acts as a kind of planetary sink for heat from the atmosphere. Exactly. And if the ocean everywhere is unusually warm, but also if the world’s largest ocean is really, really warm at its warmest point, with heat radiating outward from there into the rest of the marine system, then it stops absorbing heat.
Zeke Hausfather:
If the ocean is absorbing less heat, which is sort of the major effect of El Niño, or even releasing heat in some extreme cases, that’s going to lead to a much hotter atmosphere. And so if we didn’t have El Niño and La Nina, almost every year would set a new record in a warming world. It would be monotonic, as we say. The line would just go up. But because we have El Niño and La Nina on top of that, some years are a bit cooler, some years are a bit warmer. And so you can even think of it as like a sine wave driven by El Niño and La Nina cycles on top of an upward line.
Robinson Meyer:
You referenced the 1877-1878 event. You referenced that this could be the biggest El Niño in 500 or 1,000 years. How do we know about El Niño events before the satellite record begins in let’s say around 1980 or even before I think modern 1877, 1878 is within the realm of modern temperature reconstructions where we take land records and put them together and some ocean records and put them together and then simulate the Earth’s climate and get a decent sense of what was happening in the climate system. But how do we know about these historical events?
Zeke Hausfather:
Yeah. So there’s, for a record like 1877, 1878, there’s sort of two ways we know about it. One is that we did have a decent amount of ocean measurements that far back. And so at least on trade routes, the sailing ships were throwing buckets over the side of the ship and pulling them up with a rope and sticking a thermometer in them. So we have some measurements in the El Niño region during that event. Not very many. So there still is a pretty big uncertainty there. But we also have a reasonable estimate of global temperatures. And so you can sort of back out to an extent the strength of an El Niño from its effect on global temperatures as well. And then when you go before 1850, we don’t really have any observations. I mean, there’s some land observations, but there’s not much in the way of ocean observations. And so there you’re relying on some individual proxy measurements like corals that can tell you something about temperature at a particular time. And you’re also looking at these overall global temperature reconstructions and trying to back out the strength of an El Niño event based on, you know, how spiky global temperature is. But certainly the further you go back, the lower the resolution those things are. So like 500 years, we can probably get at least a fuzzy picture.
Zeke Hausfather:
You know, a thousand years, you’re starting to push it just because it’s hard to pick up an event that’s only a year in duration in those proxy records that might have a resolution of 10 years or 15 years. And then obviously, if you push, well, before 1,000 years, you know, you’re starting to get into the realm of a single proxy observation is going to tell you something about 50 or 100 year average. And at that point, El Niño is just going to wash out. So it does limit the extent to which we can say something about the El Niño record.
Robinson Meyer:
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Robinson Meyer:
It’s interesting because to me the 2015-2016 event was right around the same time i started covering climate change and i think it actually marked a big moment in climate discourse if i’m allowed to historicize off the top of my head about these things december 2015 which is i really right as that El Niño event was peaking was the same month the paris agreement was signed obama had just issued and was about to fight in the courts for greenhouse gas regulations on power plants under the Clean Air Act. Then, of course, we had the 2016 election, of which a large amount of the content was about climate change. And I think an underrated amount of that election was about climate policy. And then we had the first Trump administration, during which climate became a more and more salient topic politically. And so 2015, 2016, that El Niño, the earth has had most of the warmest years on record have actually happened since that El Niño. That is still the decisive event to me. And I still remember, for instance, those mass coral bleaching events of the 2015-2016 period.
Robinson Meyer:
What do we know, if anything, about El Niño now that we didn’t know 10 years ago during that event? Or what do we know about El Niño’s relationship to climate change, if anything, that we didn’t know for the 2015-2016 event?
Zeke Hausfather:
Before I answer that, I’ll answer another related question, which I think is like why these sort of events have such salience in the public discourse. And I think, you know, part of that is that climate is a slow and gradual problem and our politics are not designed around slow and gradual problems. And so when we do have these acute events, which El Niño on top of global warming represents, you know, it’s a big spike upward. It gives us a sneak peek of, you know, what the new normal global temperature condition is going to be in a decade or so. You know, it tends to focus the attention. And so I think it is important for us to use that to the extent we can, because it is a little sneak peek of what’s coming soon. But in terms of the question you asked around what we know in addition about El Niño and climate, so there certainly have been a number of papers suggesting that climate change could be making strong El Niño events more common. There’s some physical mechanisms that have been proposed, but it isn’t something that shows up particularly robustly in our climate models today. And there are a number of scientists who also argue that there’s those physical reasons that have been proposed are not super strong. So I’d put this in the same category as the debates around like wavy jet stream from global warming and its effects on cold air outbreaks, for example.
Robinson Meyer:
And the way we jet stream, just for listeners, is the idea that climate change is making those extreme cold snaps that we have had recently in North American winters where it’s suddenly negative 10 for a day or two more common because the jet stream is less stable and it dips down, allowing the so-called polar vortex to dip down over more populous parts of North America than where it normally lives.
Zeke Hausfather:
I’d put both of those ideas in this category of very active scientific debate, like the jury is out. And so hopefully in another decade, we’ll have a stronger answer in both of them and more modeling and observations. But I don’t think we can say today that there’s particularly strong evidence that climate change is going to make El Niño’s stronger outside, of course, of, you know, the background warming, just making the impacts of everything worse.
Robinson Meyer:
Right. It’s so funny. I mean, it’s one of those classic climate science discussions where it would be great to know it would be an interesting answer that we’d learn about the Earth climate system. But it wouldn’t really, I don’t know that it would have policy relevance as maybe it would. I mean, maybe we’ll learn about key El Niño mechanisms that could come important later. But the key takeaway of climate science is and remains that we should, you know, reduce anthropogenic greenhouse gas emissions as fast as we possibly can while avoiding overall harms to humanity.
Zeke Hausfather:
And the climate impacts of human emissions are just so much bigger over time than the climate impacts of El Niño, right? You know, a strong El Niño event will add about 0.2 degrees centigrade to global temperatures for a year. You know, human emissions are adding that every eight years. So every eight years, we’re adding a permanent Super El Niño worth of heat to the climate system, which just helps put things in perspective. Or 1998, which at the time was a record-shattering year, would be an exceptionally cool year if it occurred this year.
Robinson Meyer:
Given the monotonic increases of human greenhouse gas emissions every year, at least so far, what does this El Niño event mean for global temperature rise? You’ve been involved in a debate with the, I would say, storied NASA, former NASA climate scientist Jim Hansen, about whether 2026 will be the hottest year ever. Maybe fill us in on that, but generally, what does this event mean for global temperature?
Zeke Hausfather:
Yeah. So El Niño provides a temporary boost in global temperatures. We know how it’s happened historically. It’s a little harder to predict this year because we’re so far out of sample. You know, if the models are right, we end up with a peak at 4C, which is more than a degree above anything we’ve ever seen before. We don’t have analogs to draw on. But if we assume the world is linear, which we get in trouble for sometimes, we would expect a boost in global temperatures in 2027 of, you know, 0.25, maybe even up to 0.3C. And so at least my latest estimate is that this year, 2026, will be pretty neck and neck with 2024. Probably still going to be the second warmest, but, you know, maybe a 40% chance it’s the warmest, 60% chance it’s the second warmest. So getting closer and closer to a coin toss. Next year, 2027, though, is going to shatter records. So the warmest year we’ve had to date was 2024, and that was about 1.5 degrees, 1.5, 2 or so above pre-industrial levels across the average of six different data sets that the scientists have put together. 2027 in those same data sets, given what the models expect El Niño to do, would end up around 1.7 degrees C.
Zeke Hausfather:
So even compared to the previous El Niño event, which was a big boost, you know, this event is going to shatter records. And so the air bars are still pretty big on that, in part because, you know, the models have a wide range of projections. If it ends up being an El Niño that only breaks a record by a small margin instead of shattering it, the global temperature response is going to be smaller. But under any of the El Niño forecasts, 2027 is going to be a record warm year. I think the last time I checked, there was about a 95% chance it sets a new record.
Robinson Meyer:
One of the multi-year running conversations in climate science, and I would say among climate analysts as well, is that this year, as you said, temperatures will be on average about 1.5C warmer than their pre-industrial average. I believe last year we were over 1.5C as well, or very close. And one way I’ve tried to be rigorous as this has happened in the climate system is to say, look, like just because you have one year, you know, of course, at this point, about eight or nine years ago, the IPCC came out with its 1.5C report, which basically said the effects of climate change at making the planet a degree and a half warmer than their pre-industrial average will be more severe than we thought will be bad. Well, it’s a thing that’s worth avoiding. One thing I’ve been carefully rigorous about is like a single year where the global average temperature is more than 1.5C above pre-industrial average doesn’t actually mean we’ve cleared this sort of conceptual 1.5C threshold. I mean, to be clear, we are definitely going to clear the 1.5C threshold, but the first year you do it is not when you actually clear that threshold. You need several years of data above 1.5C to bring the five or 10-year moving average above 1.5. It seems like with this big El Niño, though,
Robinson Meyer:
We are going to have warm temperatures. We’re going to really push that moving average a fair amount and at least could temporarily get the threshold to be pretty close. I realize it’s hard to predict more than beyond 2027. We don’t know what 2028. We could have a big La Nina in 2028 and it could push temperatures back down below 1.5C. But maybe to tie this into another conversation. I think for the past four years or five years at this point, really since the pandemic, global warming has appeared to accelerate. And there’s been this question about whether it was caused by reductions in particulate pollution or whether it’s some other process that’s being revealed as human emissions continue to drive it. I guess the other takeaway from this big El Niño event is like that acceleration is going to continue given that we’re going to be above 1.5C this year and we could be above 1.6 or 1.7 next year.
Zeke Hausfather:
Certainly, our estimates of when the world is going to cross 1.5C have been moving closer and closer to present. One of the challenges, I think there is broad agreement now that global warming is accelerating. In fact, I went out on a bit of a limb in 2023 and published a piece in the New York Times arguing that it was accelerating back when the evidence was much more mixed than it is right now. I think the debate is less today about is it accelerating and more about exactly how much and how quickly it is accelerating. And how much of that acceleration is being driven directly by human emissions, the combination of greenhouse gases that warm the planet and cutting emissions of aerosols, sulfur dioxide in particular, that have masked a portion of historical warming. And how much of it is being driven by feedbacks to the warming process, which in many ways are the more worrying factor, right? You know, is cloud changes that we’re observing, you know, all being driven by cutting air pollution and sulfur and shipping fuel and Chinese particulates from their coal plants? Or is that change in cloud behavior and clouds being less reflective a response to the warming itself? Because it turns out that the biggest driver of how sensitive climate models are to our emissions, this factor we call climate sensitivity, essentially how much warming you get if you double CO2.
Zeke Hausfather:
The biggest determinant of that in climate models is how clouds respond in a warming world. So if the cloud feedback is strong, if clouds become less reflective, if there’s less low-lying clouds, potentially more high clouds in a warming world, then you get a lot more warming for the same amount of CO2. And so we can’t say for sure today, what mix of factors we’re seeing. But I think a lot of us are really concerned that we might be seeing an emergence of a stronger cloud feedback, which would, all things being equal, tend to imply a higher climate sensitivity.
Zeke Hausfather:
But in terms of when we’re going to pass 1.5 degrees, unfortunately, the Paris Agreement didn’t actually define what they meant by 1.5 degrees, which has caused a lot of challenges after that. And then the IPCC decided to fill in the gap. And they said, OK, we’ll define 1.5 degrees as the midpoint of a 20-year period. So 20 years is long enough that El Niño and La Nina effects will cancel each other out, and you’ll just have the human warming, the long-term effects in there. The problem with that, of course, is that means you won’t know when you’ve passed 1.5 degrees until 10 years after the fact, which is not the most useful definition. So there’s a big paper in the works that myself and like 40 other people are co-authors of that hopefully is going to come out later this summer or fall that is trying to actually answer this question and say, how do we as a community figure out a way to define when we’ve crossed 1.5 degrees that doesn’t require waiting 10 years in the future to know? There’s still a bunch of different options you could choose and different methods and ways to combine observations and models or statistical smoothing or linear or exponential projections. Anyway, there’s a million different approaches one could take. The approach we took in this paper was essentially say, okay, which of these methods got previous periods right? Like when we passed one degree or when we passed 0.5 degrees, how resilient are they to like volcanic eruptions or weird El Niños or these other sort of things. But I do think the world is probably going to firmly pass 1.5 degrees by about 2028 or so, you know, it’s coming up pretty darn quickly.
Robinson Meyer:
I’ve always felt like we needed a number that was not just how much warmer is it than average. We need a kind of global warming index number, like a climate changey index that can spit out one number that says how much worse are things right now. The issue is that once you start thinking about what such an index would look like, you realize that you basically just want the global temperature average and also that it’s basically going to go up all the time. And so it doesn’t really have a useful function, except You know, when Europe is having a giant heat wave, you could be like, oh, it’s especially climate changey right now.
Zeke Hausfather:
We do have this human-induced warming estimate that we publish every year in the sort of climate change indicators report that Pierce Foster leads. And I think this year is about 1.4 degrees of pre-industrial levels was our
Zeke Hausfather:
best estimate for 2025, which is, you know, pretty darn close to 1.5.
Robinson Meyer:
We’re talking about this question of climate sensitivity, which is how responsive is the climate system when one doubles atmospheric CO2? CO2. And in many ways, it’s one of the core questions in climate science. And for a long time, we kind of had a distribution for it. We knew what the range of climate sensitivity might be, but we hadn’t made a lot of progress in cutting off the tails. You were a co-author on a 2020 paper that cut off the extreme low end and extreme high end estimates using a number of different lines of evidence. Given what we’ve seen since 2020, where there’s been this seeming acceleration in global warming, does that affect the conclusions of that work at all? Are you more worried that we’re on the high end or that there are more extreme high end possibilities within the climate system that maybe weren’t countenanced by how that paper was run? Or are we just landing, I believe that paper was found that climate sensitivity was somewhere between 2.6 and 3.9 Celsius, are we like pointing more toward the 3.9 side than the 2.6 side, given what we’ve seen over the past few years?
Zeke Hausfather:
So we rounded those numbers a bit in terms of what ended up in the IPCC sixth assessment report. But the IPCC report said that the likely range of climate sensitivity and likely in the IPCC’s parlance means there’s a roughly two-thirds chance it’s in that range was between 2.5 and 4C per doubling CO2. And the very likely range, the 90th percentile range, which I find more useful, to be honest, because a lot of things happen outside of a two thirds chance is somewhere between 2C and 5C if we double CO2. And that’s a pretty big range, right? A lot of stuff can happen between 2C and 5C, but...
Zeke Hausfather:
You know, we are doing an updated report, hopefully in time for the IPCC 7th assessment report that’s going to incorporate all of the evidence that’s come out since 2020, because, you know, it is a big question in climate science. And there’s been a lot of work that has come out in the last six years on this topic. And, you know, I don’t want to spill the beans early, so to speak, in terms of what we’re going to find. But I will say that there’s sort of two countervailing factors, one supporting higher sensitivity and one constraining it a bit. So the thing supporting higher climate sensitivity is what we’re seeing with earth energy imbalance. So this measurement we get from satellites of how much heat is being trapped in the climate system, which is something that’s a fairly new instrument. You know, we don’t have a super long record of it, but it is in some ways the most important measure because it is capturing the sum of the whole climate system. Now, it has shown values that are a bit on the high side of what most climate models expect. And so is an indication that climate sensitivity might be on the higher end, but it is also one satellite and a relatively short record. And so there’s reasons not to just use that as the only bit of information we have. The other thing that we have is the paleoclimate records. So the Earth’s more distant past, particularly the last ice age,
Zeke Hausfather:
The Pliocene, the Eocene, these sort of periods in the Earth’s more distant past that we have measurements of both carbon dioxide and greenhouse gas concentrations, but also of temperatures from proxy records. And those tend to suggest that climate sensitivity is not much above 5 degrees C. You know, if you have a really sensitive model, for example, it’s going to run away to snowball earth if it tries to simulate the last ice age. And there’s been a lot of work by that community to use things like pattern effects and sort of how the continents and ice sheets and everything were different in that period than they are today to try to infer what the relationship in that period means for climate sensitivity today. And I think that has not necessarily been pointing toward very high climate sensitivity. But that said, 5C warming for doubling CO2 is still very much in the range of possibilities. And so there’s been a bit of a heated debate between myself and Jim Hansen and a number of other folks in the community about this topic. And Hansen’s been arguing that climate sensitivity is probably close to 5C. And the rest of us have been saying that it could be. But across all the lines of evidence we have, we don’t necessarily think that it’s more likely to be 5C than 3C, right? I personally wouldn’t be surprised if at the end of the day, in the next IPCC report, we move the best estimate up to closer to 3.5 degrees C for doubling of CO2 from three. But it’s early days, and that’s not my chapter, so I don’t get to decide that.
Robinson Meyer:
Well, speaking of emissions, you recently published a blog post on the emissions intensity of using AI. And I appreciated it for a number of reasons, including the fact that you drew on this John Bistline paper, who’s a researcher at Watershed, trying to estimate the emissions intensity of AI, which was in turn covered by my colleague, Emily Panacorvo. So always great to see heat map in the mix. But your general takeaway from this paper and also from your own estimates was that AI, probably at this point, given how we use it, is much more emissions intensive than maybe early estimates or is somewhat more emissions intensive than early estimates and you were able to put some error bars around how we should think about electricity use associated with both chatbot ai and then also agentic and cloud code style ai and describe a little bit what you think the discourse is missing right now around those topics and why you think speaking of estimates coming in on the high end why some of the more popular estimates around the emissions intensity of AI may underestimate its emissions.
Zeke Hausfather:
So when you’re looking at AI energy use, there’s sort of top-down and bottom-up approaches you can take. I think the top-down numbers are broadly right, and those are the ones that give like, I don’t know, 15% of U.S. electricity use by 2030 going to AI data centers on the high end. I’m not arguing that estimates like those are too low. What this piece was more about is, what is the impact of me as an individual using AI tools? And there, the numbers that were published last year in 2025 by folks like Google or by OpenAI are not very realistic to the way people are actually using AI today. So these numbers that were published in 2025 were that AI per prompt, and by prompt, they mean typing something in a chat GPT text box and hitting enter and getting a response without a reasoning model, important distinction. So just one shot. But those take about 0.3 watts of energy, which really isn’t much, right? At 0.3 watts, you could do many, many, many thousands or tens of thousands of AI prompts and still have much lower impact than, you know. Running your air conditioner in the afternoon or, you know, driving to work.
Robinson Meyer:
That’s less than how a light bulb used to be. So if you didn’t feel bad about adding a single new lamp to your home, then you shouldn’t feel bad, so to speak, about using AI under that estimate. Yeah.
Zeke Hausfather:
But the problem, of course, is that some people are still using AI that way, but increasingly AI is being used in an agentic form. And that more means that you give AI a set of instructions or a goal to achieve. And then AI goes off and does many, many, many, things to try to achieve that goal. AI agents are, at least in the corporate world and the software engineering and scientific world, the vast majority of AI use today. And those agents make both much more complicated calls than the prompts would suggest and many, many more calls. And so when you look at the actual energy use of these AI agents, it’s something on the order of 600 times larger per prompt than the traditional, like, type something in a chat box and got to get an immediate response. And so that does end up adding up. I actually looked at two months of my own AI use because I had local logs of all of the numbers there.
Robinson Meyer:
When you say local AI use, these are calls you’re making locally to ChatGPT or Claude that you’ve retained a record for but the ai is still being run on an external device you don’t have a power meter hooked up to your desktop
Zeke Hausfather:
Yeah my desktop is using next to nothing this is some data center spinning up to process the call i made on my local cloud code but i found that on average i was using about three kilowatt hours a day for my agentic energy use which is the equivalent of running two refrigerators so that’s not nothing in big days when i was really doing some complicated like geospatial analysis or big data crunching exercise, I was using upwards of 10 kilowatt-hours per day. So maybe a third of the typical US household energy is just going to AI agents. And if you annualize that over the entire year, you end up with numbers that they’re not crazy. So for an entire year, my estimate is that my agentic AI energy use is about 1.1 megawatt-hours. If you convert that to CO2, again, using sort of a roughly average grid intensity, It’s about 370 kilograms of CO2. So that’s roughly half of a transcontinental flight. So again, it’s not enormous in terms of my overall emissions, but it’s also not trivial, like some of these initial estimates that came out last year would suggest.
Robinson Meyer:
Carbon emissions with average U.S. grid intensity or with the likely kind of it’s all coming from gas that...
Zeke Hausfather:
All coming from gas and average U.S. grid intensity are not that far apart at the moment.
Robinson Meyer:
Yes.
Zeke Hausfather:
Yeah. So this is using a bit of location-based analysis, but it’s pretty close to the all-gas assumption now. Where I’ve gotten some criticism there is people who said, well, if you account for the fact that these AI companies are buying RECs to cover their data center energy use by building clean energy elsewhere, even if it’s not directly powering the data center, then the number is probably lower. Which, you know, might be fair if they actually disclosed what those numbers would be, I would be happy to use them. But unfortunately, at the moment, AI companies are really not telling us much about the actual energy use of their products. And so we’re having to infer all this with very indirect methods. One of the main takeaways from this piece should be a plea for AI companies to be more transparent and actually tell us how much energy their systems are using.
Robinson Meyer:
I think this is very striking, particularly by Anthropic, which I think has published absolutely no estimates per token of its emissions intensity or energy use, even though it’s the quote unquote kind of good AI company. We just are kind of completely in the dark about what Claude uses. And in fact, we know that Anthropic is contracted with one of the Colossus data centers built by XAI, which is one of the worst offenders in terms of particularly emissions-intensive generation.
Robinson Meyer:
We’re going to have to leave it there. As El Niño continues to develop, maybe we’ll have you back to talk about just how bad it is. Zeke Hausfather, thank you so much for joining us on Shift Key.
Zeke Hausfather:
Thanks, Rob. It was a great conversation.
Robinson Meyer:
And that will do it for us this week, but we’ll be back next week with a new episode of ShiftKey. Until then, Shift Key is a production of Heatmap News. Our editors are Jillian Goodman and Nico Lauricella. Multimedia editing and audio engineering is by Jacob Lambert and by Nick Woodbury. Our music’s by Adam Kromelow. Thanks so much for listening. We’ll see you next week.