Sign in

deanrovang.bsky.social

@deanrovang.bsky.social
59 followers 28 following 121 posts

Retired research engineer from Sandia National Laboratories. Interested in climate change, the energy transition, and science — with a focus on progress and curiosity. Substack: justdean.substack.com

PostsRepliesMedia
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 24/09/2026
I have submitted the latest version of my paper, The modern departure from Earth's Cenozoic temperature-CO2 relationship, to AGU Earth's Future. The preprint is on ESS OA, essopenarchive.org/doi/full/10.... . Wish me luck!
essopenarchive.org
The modern departure from Earth's temperature–CO2 relationship | ESS Open Archive
Judd et al. (2024) showed that atmospheric CO₂ has been the dominant control on Earth's surface temperature through the Phanerozoic, and presented that control as a relationship between the two quanti...
023
deanrovang.bsky.social @deanrovang.bsky.social · 24/09/2026
I have submitted the latest version of my paper, The modern departure from Earth's Cenozoic temperature-CO2 relationship, to AGU Earth's Future. The preprint is on ESS OA, essopenarchive.org/doi/full/10.... . Wish me luck!
essopenarchive.org
The modern departure from Earth's temperature–CO2 relationship | ESS Open Archive
Judd et al. (2024) showed that atmospheric CO₂ has been the dominant control on Earth's surface temperature through the Phanerozoic, and presented that control as a relationship between the two quanti...
023
deanrovang.bsky.social @deanrovang.bsky.social · 10/09/2026
Three degrees by 2100 is the number everyone carries. It's correct, and it's measuring 2100 — not the peak. On the same current-policy pathway, warming reaches four degrees in 2200 and then it stays there for centuries. 2100 isn't when the warming stops. It's where the reporting stops.
100
Reposted by deanrovang.bsky.social
Glen Peters @glenpeters.bsky.social · 02/09/2026
If you want 1.5C, 1.8C, 2C, overshoot, no-overshoot, etc, then they all require the same thing: rapid short-term emission reductions reaching net zero CO2 emissions as soon as possible. This has been clear from the IPCC Special Report on 1.5C, which depicts "overshoot" on its cover! 1/
11544235
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 03/09/2026
I think we need to try and regain the high ground from the prominent skeptics and contrarians. The CMIP7 Medium-Scenario median gets us to 4 C by 2200 and stays there for centuries. No hot models. No high ECS. No RCP8.5. No tipping points. Just present-policy apathy.
001
Reposted by deanrovang.bsky.social
Andrew Dessler @andrewdessler.com · 02/09/2026
I think people forget that keeping the climate below 1.5C was never going to happen. I think keeping the climate below 2C is possible and that's the target that I hope we don't miss.
10415
deanrovang.bsky.social @deanrovang.bsky.social · 30/08/2026
Extreme-event attribution analysis is important. I suggest every extreme event discussion, like Nepal, should carry a reminder that published multi-century projections have us reaching 4 C by 2200 and holding there for centuries, 3x our current 1.4. Let that fact carry some of the weight.
021
deanrovang.bsky.social @deanrovang.bsky.social · 29/08/2026
In the graph below, can you see the difference between Historic and Modern Climate Change? Most people can. Do you want to know the details beyond the graph? You can find them here, "The modern departure from Earth's temperature–CO₂ relationship" 10.22541/essoar.15007921/v2
011
deanrovang.bsky.social @deanrovang.bsky.social · 26/08/2026
The figures I've been posting have lived on a Substack, which is fine for readers and useless for citation. So I wrote them up properly and put it on ESS Open Archive. Cenozoic reconstruction, ice-age records, instrumental period, and CMIP7 projections on one pair of axes. doi.org/10.22541/ess...
doi.org
The modern departure from Earth's temperature–CO2 relationship | ESS Open Archive
Global mean surface temperature (GMST) and atmospheric carbon dioxide have been reconstructed separately for the Cenozoic and for the late Quaternary. Temperature has been measured directly since 1850, and CO2 since 1958. These records are rarely placed ...
263
deanrovang.bsky.social @deanrovang.bsky.social · 22/08/2026
On the left is Earth's climate before 1850. On the right is Earth's climate after 1850. What happened in 1850? We did. Want to know more? justdean.substack.com/p/earths-cli...
010
deanrovang.bsky.social @deanrovang.bsky.social · 19/08/2026
I just posted a concluding summary of my work comparing Earth's climate before and with fossil fuels. Let me know if I missed anything. justdean.substack.com/p/earths-cli...
justdean.substack.com
Earth's Climate Before and With Fossil Fuels
One figure. Two snapshots. The difference tells the story.
010
deanrovang.bsky.social @deanrovang.bsky.social · 16/08/2026
You can watch CO₂ and temperature climb together since 1850 and know something is happening. You need the last 66 million years to know it hasn't happened before. A departure needs two things: the thing departing, and the thing it departs from. justdean.substack.com/p/what-is-tr...
justdean.substack.com
What is true in life is true in climate change.
“You can't really know where you are going until you know where you have been.” — Maya Angelou
230
deanrovang.bsky.social @deanrovang.bsky.social · 14/08/2026
In "We Are in the Anthropocene—Now What?", Rockström and colleagues argue that the long-term nature of what we're doing is "highly under appreciated among the public." agupubs.onlinelibrary.wiley.com/doi/10.1029/... I went looking for a measurement of that.
agupubs.onlinelibrary.wiley.com
We Are in the Anthropocene—Now What?
The Anthropocene's enormous consequences are of long-term nature, the slow pace of recovery currently under-appreciated among the public The smallest unavoidable residual emissions (e.g., from fo...
100
deanrovang.bsky.social @deanrovang.bsky.social · 12/08/2026
I recently took some "heat" on a climate science site by a critic who said plotting GMST vs CO2 was worthless for conveying information about the influence of human activity and fossil fuels on Earth's relationship between GMST and CO2. I will let you be the judge.
010
deanrovang.bsky.social @deanrovang.bsky.social · 10/08/2026
It took us about six generations to warm Earth by 1.4 degrees C. On our present course, we will at least double that in six more generations. And then it will take hundreds of generations to cool back down. justdean.substack.com/p/six-genera...
020
deanrovang.bsky.social @deanrovang.bsky.social · 08/08/2026
@pik-potsdam.bsky.social I thought you might appreciate the use of the results from your paper in my latest Substack open.substack.com/pub/justdean...
open.substack.com
Climate Sensitivity: The Most Contestable Number
It attracts argument because it can be argued, not because it determines urgency.
020
deanrovang.bsky.social @deanrovang.bsky.social · 07/08/2026
What's going on in this graph? A lot... 66 million years of paleoclimate records, modern climate records, and model results from AR6 and AR7 all combined on one chart.
030
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 07/08/2026
Professor Rahmstorf, I thought you might appreciate seeing the results from your latest paper combined with paleoclimate records, modern records, and the Medium scenario from FaIR for AR7 combined on a single plot. justdean.substack.com/p/climate-se...
justdean.substack.com
Climate Sensitivity: The Most Contestable Number
It attracts argument because it can be argued, not because it determines urgency.
001
deanrovang.bsky.social @deanrovang.bsky.social · 04/08/2026
Climate sensitivity matters most exactly where mitigation fails, and hardly at all where it succeeds. It isn't a fixed stake we're arguing over. It's a stake whose size we set. justdean.substack.com/p/climate-se...
justdean.substack.com
Climate Sensitivity: The Most Contestable Number
It attracts argument because it can be argued, not because it determines urgency.
021
deanrovang.bsky.social @deanrovang.bsky.social · 31/07/2026
The climate has always changed. Not like this.
011
Reposted by deanrovang.bsky.social
ClimateBook @climatebook.bsky.social · 31/07/2026
Trump's latest attack on nature: this time revoking protection for the incomparable Boundary Waters Canoe WIlderness. eos.org/articles/one... This feels even more personal than most, since some of my Midwestern forebears (by marriage) were instrumental in establishing protection.
eos.org
One Billion Years Ago, Northern Minnesota Nearly Split Apart. Now, Two Companies Want to Mine the Aftermath. - Eos
A continental rift created valuable mineral deposits beneath a remote wilderness beloved by recreationists.
283
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 31/07/2026
Professor, I appreciated your previous engagement and discussion about "The Anthropocene Loop." FWIW, I just published on updated version on Substack. I would love to get your quick impressions. justdean.substack.com/p/the-anthro...
justdean.substack.com
The Anthropocene Loop
The Holocene has lasted 11,700 years. Modern climate change outlasts it.
001
deanrovang.bsky.social @deanrovang.bsky.social · 30/07/2026
Published climate projections run to 2500 and stop, with the planet still hot. Nobody in that framework asks what comes after — it isn't what the framework is for. So I extended them. The answer is measured in tens of millennia. justdean.substack.com/p/the-anthro...
justdean.substack.com
The Anthropocene Loop
The Holocene has lasted 11,700 years. Modern climate change outlasts it.
100
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 21/07/2026
I decided to take break from my usual posts about climate change and write about who I am and how I got here, i.e. tracing my ancestry back through written records and marvels of DNA haplogroups. justdean.substack.com/p/who-i-am-a...
justdean.substack.com
Who I Am and How I Got Here
The oldest thing I can tell you about myself is the thing I have known the shortest time.
131
deanrovang.bsky.social @deanrovang.bsky.social · 21/07/2026
I decided to take break from my usual posts about climate change and write about who I am and how I got here, i.e. tracing my ancestry back through written records and marvels of DNA haplogroups. justdean.substack.com/p/who-i-am-a...
justdean.substack.com
Who I Am and How I Got Here
The oldest thing I can tell you about myself is the thing I have known the shortest time.
131
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 12/07/2026
In a post on X on Thursday, Energy Secretary Chris Wright wrote that Dr. Wielicki “is an honest scientist who follows the data wherever it leads.” Okay then, Follow this! justdean.substack.com/p/the-ground...
justdean.substack.com
The Ground They Wouldn’t Fight On
What a federal panel of climate skeptics chose to argue about — and the one thing they left alone.
111
Reposted by deanrovang.bsky.social
Katharine Hayhoe @katharinehayhoe.com · 12/07/2026
Scan your local news today. How many stories are about something climate change is making worse...without saying so? I counted 8 of those in my feed today, vs just 1 that named climate change directly. Why does this matter? Research shows that making this connection changes how people see it.
Nine screenshots of my google news page today, each describing issues that are directly impacted by climate change, from more dangerous wildfire to changing flood policies.
24666308
deanrovang.bsky.social @deanrovang.bsky.social · 12/07/2026
In a post on X on Thursday, Energy Secretary Chris Wright wrote that Dr. Wielicki “is an honest scientist who follows the data wherever it leads.” Okay then, Follow this! justdean.substack.com/p/the-ground...
justdean.substack.com
The Ground They Wouldn’t Fight On
What a federal panel of climate skeptics chose to argue about — and the one thing they left alone.
111
Reposted by deanrovang.bsky.social
philsmithcross.bsky.social @philsmithcross.bsky.social · 11/07/2026
1402411546
deanrovang.bsky.social @deanrovang.bsky.social · 10/07/2026
I understand that Democrats aren't supposed to talk about climate change anymore. Maybe if we made it easy enough for everyone to see and understand how different modern climate change is from natural climate change over the last 66 million years, we could stir things up again. Just saying.
justdean.substack.com
A Different Way to See Climate Change
Dean Rovang - Staying Curious · justdean.substack.com · ORCID 0009-0006-1351-5320
000
Reposted by deanrovang.bsky.social
Gavin Schmidt @climateofgavin.bsky.social · 09/07/2026
This, I predict, will not go well.
76113
Reposted by deanrovang.bsky.social
Dr. Jeff Masters @drjeffmasters.bsky.social · 09/07/2026
I detail the incredible number of heat records set in Europe in my June monthly global climate summary post, yaleclimateconnections.org/2026/07/june...
yaleclimateconnections.org
June 2026: Earth’s 2nd-hottest June on record » Yale Climate Connections
An astonishing heat wave in Europe June 22-30 broke 10 all-time national heat records and set 394 all-time heat records at stations with a long-term period of record of at least 40 years.
03515
Reposted by deanrovang.bsky.social
Kate Marvel @drkatemarvel.bsky.social · 09/07/2026
Think positive, people
8394
Reposted by deanrovang.bsky.social
Kate Marvel @drkatemarvel.bsky.social · 09/07/2026
250 million years ago there was a massive release of greenhouse gases and ok sure it led to the extinction of most life on earth but after that we got dinosaurs
1023256
deanrovang.bsky.social @deanrovang.bsky.social · 07/07/2026
Here is the capstone my series has been building toward. justdean.substack.com/p/the-ground...
justdean.substack.com
The Ground They Wouldn’t Fight On
What a federal panel of climate skeptics chose to argue about — and the one thing they left alone.
000
deanrovang.bsky.social @deanrovang.bsky.social · 06/07/2026
If you believe that climate scientists got together and made all this up, you might be a conspiracy theorist. justdean.substack.com/p/a-differen...
justdean.substack.com
A Different Way to See Climate Change
Dean Rovang - Staying Curious · justdean.substack.com · ORCID 0009-0006-1351-5320
010
Reposted by deanrovang.bsky.social
Dr. Jonathan Foley @globalecoguy.bsky.social · 28/06/2026
What *actually* works — right here, right now — to address climate change? Here you go. This is the result of thousands of hours of painstaking research and analysis from the Project Drawdown team.
46999502
deanrovang.bsky.social @deanrovang.bsky.social · 20/06/2026
The answer my friend is blowing in the wind, the answer is blowing in the wind.
latimes.com
After nearly two decades, this massive New Mexico wind project is now powering California
One of the largest clean energy projects in United States history is now online, delivering electricity from a massive wind farm in New Mexico to Arizona and California.
000
Reposted by deanrovang.bsky.social
Zeke Hausfather @zekehausfather.com · 12/06/2026
The world has warmed by around 1.4C since 1850. It took 148 years for the first half of that warming to occur, and just 27 years for the second half!
6380208
deanrovang.bsky.social @deanrovang.bsky.social · 11/06/2026
An open letter in four questions, to anyone who finds the climate case overstated. It rests on one diagram — 66 million years of records meeting at 1850 — and on nothing any working climate scientist disputes. The questions are the kind that don't have easy answers.
justdean.substack.com
An open letter, in four questions
An open letter to the reader who feels the climate case is overstated
020
deanrovang.bsky.social @deanrovang.bsky.social · 11/06/2026
Climate sensitivity isn't one contested number — it's four, measured at different times as the same response unfolds: TCR, ECS, ESS, and the paleoclimate slope. New explainer on where each comes from, and why "sensitivity" arguments are usually people measuring different things.
justdean.substack.com
Climate sensitivity: where the numbers come from
Four quantities, four experiments, four ways of asking the same question
000
Reposted by deanrovang.bsky.social
deanrovang.bsky.social @deanrovang.bsky.social · 10/06/2026
Subsidizing coal because you hate renewables is like putting lead back in gasoline just to show that old cars worked just fine.
001
Reposted by deanrovang.bsky.social
Prof. Stefan Rahmstorf @rahmstorf.bsky.social · 07/06/2026
Do our politicians act like they are properly aware that their actions today are changing climate on Earth for thousands of years to come? Do they have sleepless nights and intensive exchange with experts over this huge responsibility?
20291114
Reposted by deanrovang.bsky.social
Andrew Dessler @andrewdessler.com · 06/06/2026
My rule of thumb is this: I would not want to live in a city where, if I trip and fall on the pavement, I could get third-degree burns. nice substack by @deanrovang.bsky.social justdean.substack.com/p/the-phoeni...
justdean.substack.com
The Phoenix We Are Choosing
When does reverse migration become the norm?
75414
deanrovang.bsky.social @deanrovang.bsky.social · 06/06/2026
My last piece, “Change the Frame, Add the Long Game,” made the case that climate communication needs to shift from near-term temperature targets toward the long-term consequences current policy is committing us to. This time I tried to bring it closer to home. justdean.substack.com/p/the-phoeni...
justdean.substack.com
The Phoenix We Are Choosing
When does reverse migration become the norm?
111
Reposted by deanrovang.bsky.social
The Weather & Climate Livestream @wclivestream.bsky.social · 04/06/2026
That's a wrap! - 50 hours of science + calling Congress - 300 letters given to Congress after a 250-mile walk We provided the templates and our viewers and supporters injected their voices. And like last year, we feel so uplifted by our community. Thank you for spending your time with us
03811
deanrovang.bsky.social @deanrovang.bsky.social · 03/06/2026
Dear Climate Change Skeptics, Please explain the diagram below without the use of greenhouse radiation physics or the addition of CO2 to the atmosphere from the burning of fossil fuels. Curiously yours, Dean Rovang justdean.substack.com
010
deanrovang.bsky.social @deanrovang.bsky.social · 02/06/2026
Latest Substack Post open.substack.com/pub/justdean...
open.substack.com
Change the Frame, Add the Long Game
The world doesn’t end in 2100 or 2150
000
Reposted by deanrovang.bsky.social
Michael E. Mann @michaelemann.bsky.social · 17/05/2026
The scenarios aren't predictions, so they're not "right" or "wrong". They are possible futures depending on our actions. The good news is that emissions are now tracking below older "business-as-usual" pathways because of climate policy in spite of Trump: thebulletin.org/premium/2025...
1526863