Jonathan Wille

The EPA is attempting to repeal its endangerment finding for GHGs—threatening decades of climate progress.

📢 Register by 12 Aug to testify at the virtual hearings (19–20 Aug): EPA-mobilesource-hearings@epa.gov

🗣️ Speak up. Science must be heard.

#ActOnClimate #AGU

10: How do we actually *know* Antarctica is melting? | Dr Michelle Maclennan Beyond the Ice · Episode

In case you need a podcast listen for the weekend, we recommend Beyond the Ice from the British Antarctic Survey. Check out the latest episode where Dr. Michelle Maclennan discusses the state of extreme weather over Antarctica and recent ice mass increases open.spotify.com/episode/30Tu...

DOE climate report response form We are collecting names to assemble a writing team to respond to the DOE climate working group report. If you'd like to contribute, enter your info below. At this point, there is no guarantee what we'll do (if anything), but we want to keep our options open by collecting names. If you have any further questions, feel free to email me. We are primarily looking for Ph.D. scientists at universities or government labs in appropriate fields. I realize that this will exclude some qualified people and I apologize, but we felt this was necessary for a variety of reasons.

🚨 If you're interested in working on a coordinated response to the DOE climate report, please enter your info on this google form 🚨

Please RT this so as many people see it as possible.

forms.gle/BL9xUAfRxA...

Motherfucking wind farms…

This proposal to revoke the Endangerment Finding will prevent the government from regulating greenhouse gas emissions now and even in the future. There will be an opportunity to publicly comment on this proposal and remind the EPA that almost all climate scientists think this report is a joke.

I've given it a quick read and quickly realized that the sections concerning CO2 as plant food were full of confirmation bias and cherry picking. Further sections about climate change scenarios used strawman arguments. I fed the report into ChatGPT which agreed with my suspicions.

A report from the Climate Working Group commissioned by the DOE is the scientific basis for the EPA's proposal to revoke the 2009 Endangerment Finding. This report, written by well-known climate skeptic scientists, is absolutely insulting to read from a science writing perspective. 🧵

🚨 The U.S. oil rig count just suffered its fastest collapse since the pandemic.

From January to July 2025, rigs dropped 13.7%, the steepest 15-week plunge in five years.

This isn’t just about oil, it’s about inflation, jobs, energy security, and the global economy.

(Save this thread)

But much more research is needed before these experimental models can be operationalised for local climate services. Again I want to thank my co-authors for supporting this research.

So is there an added value for using these high resolution, yet limited run time models? It seems mostly a yes for extreme precipitation events, especially as the nextGEMS models compared well with a regional climate model. They can provide coverage to the globally underserved in climate prediction

Finally, looking at the global daily dry fraction on a common, coarse resolution, the differences between the models is diminished suggesting that resolution is the main driver of improvements. One big theme though is the difficulty of validating extreme precipitation with Obs and reanalysis.

One possible culprit is the missing connection between moisture convergence and extreme precipitation in ICON. The lack of convection parameterization means ICON generates more bubbly, isolated convective cells instead of organized precipitation along frontal boundaries

To better understand what factors drive precipitation patterns in the models, we looked at which month contains the most extreme rainfall. Normally autumn is the primary time for extreme weather in the Mediterranean, but ICON misses this meaning a less consistent extreme precipitation forcing

The benefits of higher resolution are seen again in the 95th quantile of daily precipitation where IFS and ICON show higher rainfall values in mountainous terrain.

Moving to the high-tail end of precipitation extremes, IFS produced very high, yet reasonable values of extreme rainfall. When controlling for resolution, this improvement over CESM2 persists for both IFS and ICON. This is important for having a climate model directly simulate flooding rains.

Precipitation intermittency represents how precipitation is distributed during the year. Is it light and frequent, or intense and rare? Here IFS and ICON show clear improvements over the CESM2 which has too diffuse precipitation leading to the common "drizzle bias"

We know that ICON has no convection parameterization which leads allows it to produce more convective showers and thunderstorms, thus breaking up the dry spells over land. But this also causes the afternoon storms to be far too intense.

Greater differences are found in the average maximum annual dry spell. Here IFS and ICON produce very long dry spells compared to observations and a coarser global climate model (CESM2). The important exception here is the ICON model over land.

Focusing on the Mediterranean region, we test the added value of having very high resolution for depicting extreme precipitation (drought and flood). Starting with the percentage of days/hours with no rain, we find that the greatest improvements are over land. This is from the higher resolution

This research focused on two experimental, fully-coupled, convection permitting Earth system models designed within the nextGEMS project. The IFS model has a hybrid convection parameterization scheme and ICON has no convection parameterization. These steps help push the models to higher resolution

One motivation for developing kilometer-scale ESMs is to better understand how precipitation extremes will change in regions of complex topography. We need to provide local planners with greater detail on how precipitation extremes will challenge their infrastructure as the planet continues to warm

Extreme Precipitation Depiction in Convection‐Permitting Earth System Models Within the nextGEMS Project Fully coupled convection-permitting Earth System Models improve the depiction of wet/dry precipitation extremes over the Mediterranean region The explicit resolution of convection helps simulate ...

New paper alert 🚨 Our work on the representation of extreme precipitation events within kilometer-scale Earth system models is published. On a personal note, it's the first paper I've written that doesn't focus on Antarctica! More details below 🧵 agupubs.onlinelibrary.wiley.com/doi/10.1029/...

After a brutal start to the Alps melt season from an early season heatwave, we'll get a small reprieve with a series of cyclones drawing down cold, moist air from the north. In the highest elevations, there could be widespread accumulation of around 50 cm by Wednesday.

A large part of the western North Slope of Alaska with official forecast high temps over 90F today and tomorrow. This is borderline unprecedented if it happens. There are no weather stations in those 90F+ forecast areas though. So verification will basically be impossible. @alaskawx.bsky.social

Intense melt at high elevation and lack of freezing make juxtaglacial lakes to form as already shown at Mer de Glace near Punta Helbronner!

Here is an other example at 3430 m on Saas Fee Glacier! ❄️🧊🌊
(already existing in 2023, not shown on Swisstopo)

www.linkedin.com/posts/thomas...

New paper in ERL! We study the importance of resolution for the representation of climate extremes.

We use a new generation of km-scale models to show that many important details about temperature and precipitation extremes are hidden at CMIP6-like resolutions.

doi.org/10.1088/1748...

Our #CopernicusAtmosphere aerosol optical depth forecast initialised on 11 June showed a complex mixture of aerosols over Europe in recent days with smoke transport from Canadian wildfires interspersed with a plume of Saharan dust.

See the latest charts at atmosphere.copernicus.eu/charts/packa...

Alarmed by Trump Cuts, Scientists Are Talking Science. For 100 Hours.

To the scientists who shared their work and kept pressure building against the Trump Admin for 100 straight hours: thank you for your relentlessness.

We owe you a future of climate safety.

Following @jonathanwille.bsky.social 's recent post about an #atmosphericriver / #heatwave in West Antarctica, I did some digging in ERA5 to look at the drivers and impacts of the event. Sharing here for those who might be interested 🌨️🌡️👀

Yesterday's devastating #glacier collapse erasing the Swiss village of Blatten still leaves me speechless...
The high mountain areas are adapting to ever increasing temperatures. It's time to wake up! When, if not now?
This is not far away but right here...
pic: Pomona/A. Amherd