On Friday, I'm talking with the head of Reflective, a nonprofit trying to accelerate the responsible research of solar radiation modification (SRM), ie, blocking some sunlight from reaching earth in order to cool the atmosphere. Geoengineering! Got questions?

Giving what we can has implemented a fun game where you spin a globe to see how your starting point in life would compare if you were reborn today, randomly somewhere on earth. www.givingwhatwecan.org/birth-lottery

New paper on Marine Cloud Brightening in the Arctic! Our simulations show that the introduction of sea-salt aerosols brightens clouds in the Arctic and leads to substantial Arctic cooling, which also restores Arctic sea ice. agupubs.onlinelibrary.wiley.com/doi/10.1029/...

Reading back through @eaterofsun.bsky.social 's The Planet Remade and thought this snippet about German involvement in geoengineering research was interesting. 10 years later the opposite seems true. On the other hand, the description of GeoMIP conferences fits the recent ones pretty well..

This from @outrageoptimism.bsky.social is a great intro to recent solar geoengineering developments www.outrageandoptimism.org/episodes/jac...

Our paper is published! 🎉🎉🎉 If you want to understand changes in total rainfall under warming, give this a read! Happy to chat about it with people :) agupubs.onlinelibrary.wiley.com/doi/10.1029/...

In 2022, archaeologists at @uni-kiel.de's @neolithicbodies.bsky.social found 34 decapitated skeletons piled in a space the size of a parking spot. In the 3 years since, they’ve found 50 more. The mass grave is evidence for the collapse of the 1st pan-European culture 7,000 years ago. @science.org 🏺💀

@aliduffey.bsky.social and I have a new response to the Siegert et al piece on geoengineering published as a commentary in Frontiers (the online version is now properly edited with the figure).

Should we start historical climate simulations in 1750 (or 1800) rather than 1850? Importance of beginning industrial-era climate simulations in the eighteenth century Ballinger, Schurer et al.: iopscience.iop.org/article/10.1...

In this opinion piece, two scientists argue that the growing commercial efforts to counter climate change by reflecting away sunlight will thwart responsible research in the field.

📝 Call for all Polar Researchers to take the Science under Pressure survey! Submissions deadline is 15 November 2025 Read more and take the survey: www.rug.nl/research/arc...

"when we deploy it we will see how effective is" I hear this quite a bit but it isn't true. 10 years into a hypothetical SAI deployment, observed rainfall patterns would be pretty much useless for reducing our uncertainty in e.g. indian summer monsoon impacts

Interesting new paper from Exeter colleague Jim Haywood, and previous @exeter.ac.uk PhD student Alice Wells about geoengineering - specifically what would sulphate aerosol injection do with respect to high levels of global warming 1/2. agupubs.onlinelibrary.wiley.com/doi/full/10....

The NYT piece quoted here is amazing. Written over 70 years ago and reads exactly like articles about this summer's Texas Rainmaker conspiracy

love this chart. It's too late for 1.5, but the fight for 2C is very much still alive

wrote about this last year and sure I wasn't in any way the only one but imo people voting for populist politics in the 21st century *is* a sign that they do just have too much faith in institutions, as opposed to not enough - they want to have their little tantrum but assume things will just hold

Is this a crisis or not? Are tipping point risks serious or not? Net zero is non-negotiable, but climate impacts are here, and all plausible emissions scenarios see us pass 1.5C. If now is not a reasonable time to explore radical ideas, when would be?

One of the all-time great test matches. One of the all-time great series. Topsy-turvy, up and down and, in the end, perfectly balanced. Can't say fairer than that.

The Guardian will publish scary headlines about ice sheet and AMOC collapse on a Friday, then stuff like this on a Monday: www.theguardian.com/commentisfre... How are people supposed to navigate this? Is climate change an urgent problem, or not?

Given this context, I'm delighted to share a new review on the solar geoengineering and earth system tipping points. Its a long read including ice sheets, AMOC, coral reefs, Amazon dieback and various others.. TLDR: solar geo probably helps avoid tipping, but a lot more research is needed

New opportunity: Become a DSG Fellow and contribute to building critical expertise on solar geoengineering governance. Early- or mid-career and working in climate science, policy, ethics, law, or humanities with an interest in SRM? Apply now: www.sgdeliberation.org/our-work/res...

And remember that the peak temperatures you experience in SE England in the next couple of days will be 4-5°C warmer than they would have been with similar weather patterns in the climate of a century ago.

It was great fun collaborating with Robbie and others on this paper. The stability of the winter Arctic atmosphere is a big part of why it is warming so fast in that season, so its important to understand whether the models are doing a reasonable job, and if not, why.

In today's post I catch up with some #geoengineering #metaphors which I have been observing since around 2009 blogs.nottingham.ac.uk/makingscienc...

Feels like the 1.5C date has been coming towards us faster than we have been going towards it over the last few years

Come for the acronym puns, stay for the SAI emulator trained on data from two different ESMs across a wide range of injection strategies (great new pre-print lead by Jared Farley) egusphere.copernicus.org/preprints/20...

I had a fantastic time this week at the Degrees Global Forum on SRM. The largest conference of its kind so far, and a real step forward in diversifying the conversation on solar geo. Huge kudos to @degrees.ngo for pulling it off.

A rare win for the UK government 🇬🇧

Let’s go! 🚀 #DGF2025 kicking off today in Cape Town—the world’s largest-ever forum on solar radiation modification and the first held in Africa. Over 330 participants from 30+ countries are here to shape the global conversation on the science, equity, and governance of SRM.

I've always been open about my belief that having +research on SRM is good, so to me the ARIA program is very welcome. Most of the funded research is about expanding our understanding of potential outcomes through modeling, obs and engagement. Yes, there are some outdoor scientific experiments:

ARIA just announced their funding allocaitons for their £57 million worth of research into solar climate intervention Lots of exciting projects from a real diversity of approaches www.aria.org.uk/opportunity-...

Another great article on @aliduffey.bsky.social 's latest work by the amazing journalist @chelseaeharvey.bsky.social . This one is behind a paywall but check it if you can www.eenews.net/articles/sol...

Jiminy Cricket! It’s an #IceAge grasshopper! The so-called ‘Grasshopper of Enlène’, engraved on bone some 17,000 - 14,000 years ago, is the most detailed representation of an insect in Paleolithic art known to date. From the Enlène Cave, Ariège, France. Magdalenian period. 📷 me #Archaeology 🏺

I don't love the headline here, and the comments section leaves a lot to be desired.. but its great to see this coverage of our new paper giving space to both the risks and the potential benefits of SAI www.telegraph.co.uk/news/2025/04...

I'm really pleased to share this paper, published today in Earth's Future. Running the 45 climate model simulations we used was a lot of work, so its a great feeling to see our findings out in the world. agupubs.onlinelibrary.wiley.com/doi/full/10....

A technique to cool the planet, in which particles are added to the atmosphere to reflect sunlight, would not necessarily require developing special aircraft but could be achieved using existing large planes, finds a new modelling study led by PhD student @aliduffey.bsky.social @es-ucl.bsky.social

I really enjoyed this book. "Climate isn't everything" is often what I say when I'm trying to convince people that no, we shouldn't just start solar geoengineering tomorrow. Useful to see that argument carefully put forward.

The agenda of the Degrees Global Forum on SRM is online! If you are coming to Cape Town next month, plant your time! If you are not coming, then browse and reconsider! degreesglobalforum.org/about/agenda/

We've focused a lot on the effects of low sulfur fuel standards on recent warming, but in some ways whats happened in China is even a bigger story. They have reduced their SO2 emissions nearly 75% since 2005, resulting in ~0.06C (0.02C to 0.11C) warming.

I have a letter in the @theguardian.com in response to the oped from @michaelemann.bsky.social and @climatebook.bsky.social which called for @aria-research.bsky.social's climate intervention programme to be defunded. www.theguardian.com/environment/...

thebulletin.org/2025/03/fore... Me and my colleagues at Cornell wrote for the @thebulletin.org: “Put bluntly: Americans will die and American businesses will lose untold billions if we do not protect NOAA and NWS.”

Aspirin (safe but low impact) is a terrible analogy here. chemotherapy is the better analogy if we must use the cancer metaphor — powerful but risky, potentially a net benefit despite direct harms, and you wouldn't even consider it if things weren't really bad www.theguardian.com/commentisfre...

🚢 First-ever African marine cloud brightening study published!☁️ A Degrees-funded team in South Africa led by Romaric Odoulami finds MCB over the Southeast Pacific has the strongest cooling effect. But crucially, where it's deployed makes all the difference. Read more: www.degrees.ngo/brightening-...

For anyone in Cambridge this evening and interested in hearing about solar geoengineering. The panel is full of very cool speakers (and also me)

Psst…You want to know about the NASA website that spells out your name in Landsat imagery. 🧪 landsat.gsfc.nasa.gov/apps/YourNam...

In 2024, DSG and the African Climate Foundation hosted a workshop series to build African perspectives on SRM. Participants from across the continent examined SRM’s potential role in climate response, governance challenges, & ethical considerations tied to climate justice.

I enjoyed this conversation a lot. Have a listen if you want to hear my thoughts on using stratospheric aerosol injection to cool the planet