Maybe it’s just that phenomenon where when you buy a green car all of a sudden you see green cars everywhere, but I have been seeing Earth’s energy imbalance (EEI) discussed a lot more lately. And that is a very important thing. Quico Toro wrote a good article on why everyone at Climate Week was talking about it. At the beginning of September, the Climate Vulnerable Forum, a group of 74 climate-vulnerable countries, put out a science bulletin called The Earth’s Energy Imbalance and the Reflectivity Crisis, subtitled “the second global warming problem.” The Cleaning Up Podcast just released an episode titled “Is The Earth Warming Faster Than We Thought?” And the World Meteorological Organization also made EEI one of its headline climate indicators for the first time this year.
Earth is taking in more energy from sunlight than it sends back out to space, and that gap has roughly doubled since the early 2000s. Part of that comes from feedback loops that are making things worse (less sea ice and snow, fewer bright clouds), and part of it, perhaps counterintuitively, comes from cleaning up air pollution that had been reflecting some sunlight back to space. Most of the speed-up shows up as Earth getting darker and reflecting less sunlight. This is increasingly becoming a frightening problem, because the energy imbalance gap is growing faster than climate models expected and the measurements are making the gentlest climate outcomes look less likely.
It’s also why I think we should be putting more resources into monitoring and observation and trying to understand it. According to the CVF bulletin, the satellite record that measures this is aging, with one of NASA’s CERES instruments switched off last year and the Terra satellite’s science mission expected to end early next year. The successor instrument, Libera, doesn’t launch until 2027, and there are currently no plans for anything after it. Meanwhile, the US budget request for next year proposes cutting NASA Earth Science by more than half. The CVF is recommending that its members make continuity of these measurements a formal position going into COP31 in November, pointing out that the countries least responsible for the imbalance are “the most exposed to losing the ability to measure it.”
I wanted to put together a simple microsite for this so that people could understand what is going on in a more accessible way, and it’s now live at earthenergyimbalance.com. At its center is a 90-second animated video, and the rest of the page walks through the latest reading, why the planet is getting darker, why it’s a risk and what can be done about it. Spark Climate, Probable Futures, and Carbon Brief all have good written explainers, and the site links to them, but I wanted something short and visual that you could send to someone who hasn’t heard of EEI yet. (I built the animation with Opus 5.5, after seeing a lot of examples on social media of what people were doing with it.)
One thing I’ve heard over and over again from people who work with policymakers is how critical neutrality is in describing problems. So the site starts with the problem, gets you to understanding what it is and what its implications and consequences are, and only afterwards gets to the things we might do to respond.
The site is really meant for people who are climate aware but not necessarily familiar with this level of nuance. I suspect most of you know a few of them, so please send it their way. And if you spot anything wrong, or anything that confused you, reply to this email or leave a comment and I’ll fix it (if you work on this science, I especially want to hear from you).
Nice explainer and video. You're right EEI is now a hot topic (sorry), perhaps because the CERES record is 25 years old and the trends have clearly emerged from the noise. AR6 covered it well but it didn't reach the outside world.
I have further details including the break down between shortwave reflection changes and long wave output changes if your readers are interested: https://drtomharris.substack.com/p/earths-energy-imbalance-quarter-century
Anyone writing about Earth's energy imbalance shouldn't be using cloud-based AI tools to make 90 second videos given how much data centres rely on fossil fuels. I appreciate your emails, although I'm agnostic about some of the solutions you propose to the climate crisis but completely on board with investing energy in the scientific understanding of what's happening, and there's a role for cloud-based AI tools where the opportunity cost of human brain power outweighs the benefit of the science. But making educational videos ain't it.