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R. Saravanan

@sarava.net

3.2K followers 580 following 700 posts

Climate scientist, Professor, and Dept Head at Texas A&M University. Author: ClimateDemon.com Now-and-then-blogger: https://Metamodel.blog Bio: https://r.saravanan.us/about

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R. Saravanan @sarava.net · May 28

I'll be speaking tomorrow, Thurs., May 29th, at 9:30AM Eastern Time in the Weather & Climate Livestream
www.youtube.com/@wclivestream

Topic: Using climate models to predict solar and wind power droughts, i.e., periods when it is Dark & Still

(agupubs.onlinelibrary.wiley.com/doi/full/10....)

Dark Stillness: Predicting Solar and Wind Power Droughts, R. Saravanan, https://r.saravanan.us

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Reposted by R. Saravanan

derek guy @dieworkwear.bsky.social · 19h

This two-parter below is exactly why it's hard to make clothes in the United States.

Let's look at how much it costs to produce a button-up shirt in the US. 🧵

Someone on Twitter replies to me: "meh. buy american or stfu."

Two hours later, in a separate thread, the write: "$30 for a single button-up is ridiculous unless it is decent quality silk."

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Walter Olson @walterolson.bsky.social · 2d

New from me at Cato: I go through the numerous and massive First Amendment and academic-freedom violations of Trump's proffered "compact" with universities and then talk about the mechanism by which it would be enforced, by way of what I describe as a "retroactive push-button guillotine."

Universities Must Defend Their Independence by Rejecting Trump's "Compact"

The Trump administration has proffered a “compact” to universities that would require them to surrender their independence and academic freedom. How many First Amendment violations can we identify in ...

www.cato.org

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R. Saravanan @sarava.net · 2d

Climate is a long-term (multidecadal) average. Looking at a few warm months, or even a few warm years, does not change conclusions. That's why we use large ensembles of model simulations to create an envelope of climate realizations. The recent warm months still fall within the envelope (so far ...)

R. Saravanan @sarava.net · 3d

Damages/deaths due to climate-linked disasters can be due to poor adaptation to the "unchanged" climate (e.g. building in known flood plains in Bengaluru/Chennai) as much as they are due to a changing climate (heat waves in Europe). Without counterfactual adaptation scenarios it is hard to attribute

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R. Saravanan @sarava.net · 3d

The "mainstream" consensus is that Hansen's estimate of climate sensitivity are too high.
To precisely predict when we'll reach 2C, we need to predict precisely human behavior, which is hard/impossible. My "gut feeling" is that we'll reach 2C in several decades but we'll survive (like Tina Turner).

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Juno Rylee Schultz @junoryleejournalism.com · 4d

David Simon, creator of ‘The Wire’, being interviewed by Ari Shapiro (NPR)

SHAPIRO: OK, so you've spent your career creating television without Al, and I could imagine today you thinking, boy, I wish I had had that tool to solve those thorny problems...
SIMON: What?
SHAPIRO: ...Or saying...
SIMON: You imagine that?
SHAPIRO: ...Boy, if that had existed, it would have screwed me over.
SIMON: I don't think Al can remotely challenge what writers do at a fundamentally creative level.
SHAPIRO: But if you're trying to transition from scene five to scene six, and you're stuck with that transition, you could imagine plugging that portion of the script into an Al and say, give me 10 ideas for how to transition this.
SIMON: I'd rather put a gun in my mouth.

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Dr. Robin Tanamachi 🌪️ @tornatrix.bsky.social · 5d

While I’m at the UCAR Member’s meeting, I’m reminding everyone of the internships, workshops, and other student opportunities that they have available! www.ucar.edu/exhibit/stud...

Exhibit resources | University Corporation for Atmospheric Research

www.ucar.edu

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Reposted by R. Saravanan

Andrew Dessler @andrewdessler.com · 11d

The Dept. of Atmospheric Sciences at Texas A&M has a YouTube channel. Check out our first video! Starring @knubez.bsky.social along with many faculty and students!

youtu.be/_e57SmX2Ijw?...

Texas A&M Atmospheric Sciences

YouTube video by TAMU Atmospheric Sciences

youtu.be

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R. Saravanan @sarava.net · 12d

Any plot of future warming will depend on assumptions such as pledges being implemented or specific policies being continued.
Actual policies only affect the present. Mitigation only affects warming thus far and cannot "reduce future warming"
(if fossil fuel use for AI ramps up, the world will warm)

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Tomer Burg @burgwx.bsky.social · 13d

Adding my 2 cents to the discussion on Google DeepMind’s performance for Imelda… 🧵

You might see a map like this and be impressed that at no point did it predict landfall in the US. But there is a lot of context lost by simplifying it to just one image.

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Reposted by R. Saravanan

Dr. Aaron Thierry @thierryaaron.bsky.social · 13d

"In science, to be ‘conservative’ is to understate your findings. In insurance, it means the opposite: erring on the side of overstatement of risks. For a clear assessment of the risks of #climate change, we need these two cultures to meet in the middle"

www.cambridge.org/core/books/a...

The Meaning of Conservative (Chapter 6) - Five Times Faster

Five Times Faster - November 2024

www.cambridge.org

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R. Saravanan @sarava.net · 13d

As a prof who teaches coding, this line in Armin's post stood out:
"I still review every line, shape the architecture, and carry the responsibility for how it runs in production."
How do I teach the skills to be able to do this? It requires carefully controlled incremental exposure to LLM coding.

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Simon Willison @simonwillison.net · 14d

Most of the "90% of code written by AI" claims come from vendors selling AI tools and lack credibility as a result

Armin (creator of Flask, Jinja, Click) is different - when he says 90% of a new significant infrastructure project he's building was AI generated that's worth paying attention to

Armin Ronacher @mitsuhiko.at · 14d

“Is 90% of code going to be written by AI? I don’t know. What I do know is, that for me, on this project, the answer is already yes.” lucumr.pocoo.org/2025/9/29/90...

90%

AI is writing 90% of the code I was in charge of

lucumr.pocoo.org

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Reposted by R. Saravanan

National Weather Service @nws.noaa.gov · 14d

Quite a satellite image this morning! 🛰️🌀

Clouds extend 1000 miles from #Imelda's center all the way into central Pennsylvania.

#Humberto continues to churn in the Atlantic.

Visible satellite image of the East Coast and Atlantic showing the two tropical system.

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R. Saravanan @sarava.net · 15d

Nice piece. "Scientific" is a better adjective than "natural" when assessing efficacy and impacts. In the climate mitigation arena, most nature-based carbon offset schemes are either ineffective or just scams. (We may discover effective nature-based schemes, but only science can tell!)

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Michael Grunwald @mikegrunwald.bsky.social · 15d

My latest effort to be super-popular in @nytimes.com: “Spraying Roundup on Crops Is Fine. Really.” Yes, the world’s most hated herbicide is way less toxic than caffeine. Here’s a gift link where you can leave all your supportive comments: www.nytimes.com/2025/09/28/o...

Opinion | Spraying Roundup on Crops Is Fine. Really.

www.nytimes.com

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Kelly Hereid @kellyhereid.bsky.social · 17d

90 of 111 fatalities from Hurricane Rita happened due to the evacuation. 20 years later, would we do any better?

@sarava.net shouting out the value of much improved track forecasts

🎁 link:

20 years after Rita’s gridlock nightmare, is Houston ready to evacuate again?

Stalled and overheated cars, endless gridlock and nearly 100 deaths. The deadly Hurricane Rita evacuation is still etched in the memories of many Houstonians 20 years later.

www.houstonchronicle.com

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Nick Lutsko @nick-lutsko.bsky.social · 17d

I wrote a short piece on the debate about the future of climate modeling: Should we pool resources to do km-scale "masterpiece" runs or focus on using ML to build data-driven models that can still do large ensembles? 1/3

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R. Saravanan @sarava.net · 17d

If we can't decide, how do we know if an ML model is "better" than a physical model?
For ML emulators, how do we know the extreme tail using a very large (~10,000) ensemble is correct if we can't afford a very large physical ensemble to verify it? (We don't have data to verify such extremes) 4/4

R. Saravanan @sarava.net · 17d

It is also important to agree on metrics. How you decide if predictions (of mean & spread) from Model A are better than predictions from Model B? For 1-day prediction, it is easy to verify forecast skill. For predicting the year 2100, how do we decide which prediction is better? 3/n

R. Saravanan @sarava.net · 17d

Do you want predictions at lead times of 1 day, 1 month, 1 year, 1 decade or 1 century? Do you want to predict emergent metrics like ECS/global-avg T, or future rainfall/T extremes at the county or zip code level?
it is important to define the goals. 2/n

R. Saravanan @sarava.net · 17d

It is indeed an emerging and interesting debate. At present, the physical models run on CPUs and the ML models run on GPUs. So they're not directly competing for computer resources. That will change though.
The debate is clouded because the prediction goals are poorly defined. 1/n

Reposted by R. Saravanan

Shel Winkley @shelwinkleywx.bsky.social · 17d

📱 Come make meaningful content with us!

This gives a creative, climate-motivated creator the chance to bring science & data to life through digital storytelling.

Grow your video & editing skills while communicating climate change impacts. (Probably work in a little fun along the way, too!)

Climate Central @climatecentral.org · 17d

What @ariellemargot.bsky.social said.

We're hiring a Social Media and Digital Content Creator!
www.climatecentral.org/open-positio...

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R. Saravanan @sarava.net · 17d

If you compared the ACE2 emulator results to those obtained using a baseline multivariate linear regression model built using the same EAM training data (perhaps using a truncated EOF basis as predictors), how would the emulator fare?

R. Saravanan @sarava.net · 18d

What does "act now" mean?
Not saying 2C is achievable, but it is a more "realistic" goal, for a T target. I personally prefer emission targets, i.e., near net-zero. At present, there is no viable negative emissions tech (and there may never be). Geoengineering may create more problems than it solves

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