Dagomar Degroot
@dagomardegroot.bsky.social
Professor of environmental history at Georgetown University. Creator, "The Climate Chronicles." Author of the new book, "Ripples on the Cosmic Ocean." Interested in all things climate change, outer space, existential risk, and past for present.
New from me: Climate change is eating away at Svalbard's largest whalers' graveyard, threatening bones and textiles preserved in the 17th-century burials as well as the scientific data embedded in them 🧪⚱️❄️
Thawing permafrost is threatening Svalbard's 'corpse point'
Human bones and artifacts from the largest whalers’ graveyard in the archipelago are at risk of disintegrating.
nationalgeographic.com
My take on #America250. Both trends and anomalies in weather have shaped the history of the United States. And if we don't restore efforts to slash greenhouse gas emissions, #ClimateChange could make for a grim 300th. sciencepolitics.org/2026/07/13/h... #ClimateChange #America250
How Climate Change and Weather Shaped 250 Years of U.S. History - Science Politics
Cold, rain, drought, and warming have both helped and harmed Americans' efforts at pivotal moments.
sciencepolitics.org
ICYMI: @harrycroft.bsky.social reflects on his experience at our Canadian History of the Enviornment Summer School in PEI! niche-canada.org/2026/07/04/s... #envhist #cdnhist #PEI
Speed CHESS 2026: A First-Timer's Account
Harrison Croft, a Germany-based historian, attended the CHESS meeting in PEI, exploring climate resilience, parabolic sand dunes, and local environmental histories.
niche-canada.org
July ECMWF runs are in and forecast an even more extreme El Niño event than the prior June runs. ENSO3.4 region temperatures reach 3.9C in December, and forecasts are around 0.3C warmer than they were in June.
The reason why it is essential to read IN BULK when studying history is not simply to amass empirical knowledge—though that is important, too, of course—but because *interpretation* requires thick contextual awareness, and there is NO SHORTCUT for building that up that awareness.
Did you know? Renewables have just overtaken coal as the world's largest source of electricity 34% – global renewable share, up 2x in 20yrs 48% – EU 37% – China 26% – US 24% – India
Want to write a peer-reviewed, Oxford Intersections article on the #EnvHist of disasters? Check out our call for papers! Oxford Intersections offers a quick, respected, high-impact publishing format - perfect for new research in environmental history. academic.oup.com/oxford-inter...
Clare is a remarkable person in so many ways. This is vital reading.
Clare Fieseler, PhD@fieseler.bsky.social · 2mo agoI’ve been quiet. Here’s why: At my 20-year college reunion in May, dozens of old friends arrived at our campus and started snapping photos on Georgetown’s front lawn. I, too, was on campus, but on the back side, at the university hospital, laid out on a gurney in the emergency room’s trauma suite…
Big histories of #ClimateChange are always full of mistakes, partly because climate science is constantly changing. Because my "Climate Chronicles" is not a book, I can fix my errors. I've now published a list of the revisions I plan to make this year. #EnvHist theclimatechronicles.com/revisions/
Revisions - The Climate Chronicles
The Climate Chronicles attempts to explain how climate change shaped the history of our species. That’s a daunting challenge, for at least three reasons.
theclimatechronicles.com
This really would be the end of science in the US marginalrevolution.com/marginalrevo...
The Nationalization of American Science - Marginal REVOLUTION
OMB, joined by some forty grantmaking agencies—NSF, HHS, DOE, NASA, DOD among them—has proposed a sweeping rewrite of the rules governing all federal grants, the Regulation for Federal Financial Assis...
marginalrevolution.com
Today at 5 PM EST! Join @amandagefter.bsky.social and me for a conversation that spans Earth and the solar system, exploring how natural and human histories intersect. We'll talk about everything from #climatechange to #alien civilizations - it should be fun. #EnvHist #Astronomy luma.com/apv6a38z
Space Weather and the Course of History · Zoom · Luma
Often when we think of space we think of “out there.” The wonders beyond. But out there includes us! Let’s talk about the weather. On Earth it can delight or…
luma.com
Event - Reflections on Resilience: 20,000 Years of Climate History A Climate History Plenary with @dagomardegroot.bsky.social Part of #CHESS2026 Sunday – 31 May 2026 – 17:30-18:45 ADT Murphy Student Centre 110 (McMillan Hall) – University of Prince Edward Island niche-canada.org/2026/05/22/e...
Event - Reflections on Resilience: 20,000 Years of Climate History
31 May 2026 - Charlottetown, Prince Edward Island - Dr. Dagomar Degroot is a leading climate historian from Georgetown University. He has published several high-impact, award-winning books on climate ...
niche-canada.org
A study in Nature Sustainability shows sea-level rise is already causing population retreat in coastal Louisiana and uses geological history and demographic data to argue that early, planned relocation can guide global climate adaptation. go.nature.com/4eHOh6q 🌍🌊🧪
As @climatechirper.bsky.social says, "The deliberate actions of colonialists in the 1870s disrupted local systems that communities relied on for being resilient to climate variations." So, it's wrong to claim that it was #ElNino that killed millions in 1877. www.washingtonpost.com/weather/2026...
A super El Niño wiped out millions of people in 1877. Are we better prepared now?
The climatic phenomenon is expected to return this year, but a lot has changed since what might have been the worst environmental disaster in human history.
washingtonpost.com
No. Instead of thinking, "what do people want to hear, and how can I give it to them?", politicians should ask, "what do I think is important, how can I explain why it's important, and how can I offer solutions?" Authenticity matters, now more than ever. #Climate www.nytimes.com/2026/05/09/o...
Opinion | Forget Climate Change. Democrats Need to Talk About Other Issues.
nytimes.com
Had I been interviewed for this article (rather than merely quoted), I would have said: We don't seek signs of #ClimateChange in early modern (EM) art because today's climate is changing. We seek it because the early modern climate changed. (1//2) www.jns.org/feature/once...
Once jeered as too pretty, Impressionism is now marshaled in climate-change activism
Even as they bring contemporary politics into the story, museums tend to overlook the antisemitism that divided Impressionists over the Dreyfus Affair in the late 19th century.
jns.org
This is incredible. The new NASA image release from #Artemis includes a sequence of 'Hello World' still photographs. I've been processing / animating them and here's what the original didn't show us: Satellites, including their solar arrays, lightning storms and dancing aurora!
"Project Hail Mary" imagines how an environmental change on the Sun spurs an effort to protect the environment of Earth. In a way, it's the thrilling, fictional counterpart to my new book, "Ripples on the Cosmic Ocean." #EnvHist #ProjectHailMary sciencepolitics.org/2026/05/01/p...
Project Hail Mary Tells a True Story About Humanity’s Past and Future - Science Politics
Changes in solar environments could pose serious risks to modern life.
sciencepolitics.org
How can records of the past inform our understanding of extreme events? Join the National Academies on April 29 for a webinar releasing a new report on a proposed Center for Paleoenvironmental Records of Extreme Events (CPREE). Register: events.nationalacademies.org/46602
Functions and Criteria for a New Center for Paleoenvironmental Records of Extreme Events: Report Release Webinar
Register for this event from the National Academies of Sciences, Engineering, and Medicine.
events.nationalacademies.org
It's a little hard to fit everything into news stories like this but something I wanted to spell out - Prof Yasuyuki Aono was an *incredibly* dedicated person, by all accounts, who brought us the now-famous cherry blossom climate indicator. www.theguardian.com/world/2026/a...
After 1,200 years, cherry blossom record to live on despite Japanese scientist’s death
Prof Yasuyuki Aono’s meticulous work charted shifting bloom dates as a marker of climate change
theguardian.com
Collapse! Mega-drought! The 16th episode of The Climate Chronicles explores whether a wave of drying brought about the collapse of the world's first empire, 4200 years ago. It's a huge episode: more than 8000 words and 65 mins of audio. #EnvHist theclimatechronicles.com/2026/04/07/e...
Episode 16: Megadrought in Mesopotamia - The Climate Chronicles
More than 4,000 years ago, a wall seems to have gone up across what is now northern Iraq.
theclimatechronicles.com
This second edition is essential reading - for everyone. If there’s one book I’d recommend in environmental history, it might be this. With an introduction by @brdemuth.bsky.social! #EnvHist
Excited to discuss "Ripples on the Cosmic Ocean" at Georgetown on Monday. And talk about timing. Seeing the Moon this morning, knowing that the #Artemis astronauts just flew around it, gave me the most surreal sense of Earth's precarity in a dynamic universe. events.georgetown.edu/eia/event/ri...
The combination of a very strong #ElNiño - which should reduce harvests across Asia, Australia, Africa, and parts of the Americas - with soaring fertilizer and fuel prices, owing to the ongoing closure of the Strait of #Hormuz, could make for a devastating year of food shortages and social unrest.
Zeke Hausfather@zekehausfather.com · 4mo agoI've updated my El Niño forecast plume with the latest April data (ECMWF, NMME, CFSv2, Canadian models). Its now looking like it might end up giving 2015/2016 a run for its money in terms of strength, with a peak of ~2.6C in the ENSO3.4 region by end of year: dashboard.theclimate...
Recently, I enjoyed chatting about the history, and possible future, of #ClimateChange. First - did drought cause social unrest and conflict in the late Roman Empire? Tree ring evidence suggests maybe, but the textual evidence seems ambiguous. (1/2) www.newscientist.com/article/2520...
Historians dispute link between drought and rebellion in Roman Britain
A study based on tree rings claimed that droughts played a role in events that led to the Roman withdrawal from Britain, but other researchers say that isn't backed up by historical evidence
newscientist.com
I knew about the 1969 moon landing. And knew that news of the My Lai massacre came out in '69. But I had those events in separate boxes. Occurs to me now that it must have been disorienting to feel proud of (one aspect of) your country, while also deeply shamed by its crimes.
“But ultimately, we will always choose Earth. We will always choose each other.” —Artemis II astronaut Christina Koch
