Line graph time series of glaciers around the world for cumulative mass change since 1950 from a reference period of 1992. All areas are decreasing.

Cumulative change in the mass of glaciers from all around the world - preliminary data just updated through 2025 ☹️

Information on methods: wgms.ch/products_ref...

The most rewarding part of the job 💚

Wow, much to unpack. But for starters, the intellectual (not to mention field and lab!) work my grad students do simply couldn’t be done by existing AI. (Good new ideas? Not likely.) So I don’t even get the base version of this take. Maybe that’s a diff in what research looks like in diff fields? 🤷‍♀️

Fab new review alert! 🔥🤓
There's so. much. data compiled here in one place! ⚛️ On so many different water isotopes proxies. Should be very useful for old hands and water isotope rookies alike. It was so fun to contribute a tiny piece to this joyously epic & careful review led by @isotopes.bsky.social

'Greenland belongs to its people': The US scientists speaking out against Trump's imperial aggression At least 225 US scientists who conduct research in Greenland have signed a Statement in Solidarity with Greenland this month.

Kalaallit Nunaat belongs to its people. 🇬🇱

If a 'framework' for Greenland’s future emerges from international discussions in the coming days, it must be a plan that Greenlanders want.

🙏

🙏

Statement from U.S. Scientists in Solidarity with Greenland STATEMENT FROM U.S. SCIENTISTS IN SOLIDARITY WITH GREENLAND Amerikarmiut Kalaallit Nunaanut misissuiartortartut nunatsinnut ataqatigiinerannu...

To Greenlanders: thank you for years of friendship and partnership; we stand with you. Qujanaq, ilagaasi.

U.S. scientists: Write your reps in D.C. TODAY. Urge them to support Greenland's right to self-determination. Insist the U.S. engage respectfully and peacefully with our ally. bit.ly/3LjITdm

A photo of the waterfront in Nuuk, Greenland from November 2025.

175 U.S. scientists who do research in Greenland have already signed our Statement from U.S. Scientists in Solidarity with Greenland. With more signatures coming every hour.

Greenland belongs to the people of Greenland.

And to Greenland’s people: Qujanaq, from the bottom of my heart, for all the ways you have supported my students and me in our quest to understand Earth's climate. I have deep respect for your knowledge of the Arctic and for your right to make decisions about your homeland. 🙏 I will speak out.

To my fellow Americans, including American scientists: Please push back loudly against the Trump administration's damaging, disrespectful rhetoric towards Greenland. Greenlanders have long been generous and important allies to our nation, including American scientists like me.

Vi har været USA’s nære og loyale ven i generationer. Vi har stået skulder ved skulder i svære tider. Vi har taget ansvar for sikkerheden i Nordatlanten og ikke mindst Nordamerika. Det er sådan… | Jen... Vi har været USA’s nære og loyale ven i generationer. Vi har stået skulder ved skulder i svære tider. Vi har taget ansvar for sikkerheden i Nordatlanten og ikke mindst Nordamerika. Det er sådan rigtig...

Greenland's prime minister responded to Trump and Trump's associates on LinkedIn Jan 4: www.linkedin.com/posts/jensfr...

Photo of green aurora borealis arcing through the night sky above the city lights of Nuuk, Greenland's capitol, in November 2025.

Greenland's flag - bands and half-discs of red and white. Its shapes represent glaciers, the ocean, the Sun, and ice.

Greenland is a peaceful democracy, and it belongs to Greenland's people!!

"We have been America’s close and loyal friend for generations,” Greenland's democratically elected prime minister Jens-Frederik Nielsen stated today. "Enough is enough. ... Greenland is our home and our territory.”

Photo of an icy fjord near Nuuk, Greenland, with snow- and ice-capped mountains in the background.

Photo of green aurora borealis glowing in the night sky over the city lights of Nuuk, Greenland.

Thrilled to be in beautiful Nuuk for Greenland Science Week. What a special place. And what an opportunity to learn from Greenland's scientists & community members. Qujanaq/tak to our hosts: Arctic Hub, Asiaq, Ilisimatusarfik, Grønlands Naturinstitut. (Colleagues who are here, let's connect!)

TIL that the feminine plural of "bravo" (applied to a group of women or girls) is "brave" - and now I want to use this word all the time 💪

I saw press coverage of this today, and didn't have time to click links - didn't realize it was you guys! Congrats to Andy and team on the nice work. 👏

This research (and training of the next generation of scientists) was funded by the US National Science Foundation. Americans can stand up for science by asking their Senators and Representatives in DC to support NSF and American science. It's urgent to call this week, especially. Thank you!

I should clarify that cyanobacteria are cool, common in Arctic lakes, and not necessarily yikes. What's yikes to me is the speed and intensity of changes driven by just a few degrees C warming ~6600-3500 years ago. Alongside (from other studies) major glacier loss & species migrations. Big impacts.

Mia is a highly talented PhD student approaching graduation at a tough time for U.S. science. I have to highlight another neat thing she's been up to: Art/science/community collaborations in the very special south Greenland town of Narsaq: www.miattuccillo.com/community-ou...

Aquatic plant wax hydrogen and carbon isotopes in Greenland lakes record shifts in methane cycling during past Holocene warming δ2H values of aquatic plant wax reveal past Holocene warming led to expanded CH4 cycling in lakes across Greenland.

Note that @isotopes.bsky.social (with other methods) found that lakes lost hypolimnetic oxygen in three more (far-away) sectors of Greenland around the same time. Oxygen depletion was apparently widespread, in response to a few degrees of summer warming. www.science.org/doi/10.1126/...

Mia painstakingly extracted photosynthetic pigments from 7,000-year-old sediments to figure this out. Super cool! (3/3) Gift link here: authors.elsevier.com/c/1lrE5-4PSD...

Links between warming and lake-water quality are especially important in Greenland, where communities use rivers and lakes for drinking water. Congrats Mia, and thanks to Greenlanders for access to our research sites! 🙏 (2/3)

Earth scientists Maggie Osburn and Mia Tuccillo bag up plant samples in a rocky Greenland landscape, with an iceberg-spotted fjord and glacier-covered mountains in the background.

New paper! PhD student Mia Tuccillo has uncovered another big impact of past warming in Greenland: lakes lost oxygen for thousands of years and cyanobacteria took over 🦠 🧪 🦠. It's kinda yikes...
With collaborator @geobiomaggie.bsky.social (1/3)

Image shows the cover of Peter Brannen's forthcoming book, titled "The Story of CO2 Is the Story of Everything." The cover is a cartoon image of geologic layers in bright colors.

This title from @peterbrannen.bsky.social! 🤩 If only I were better with words, this could have been the name of ALL my climate and Earth history courses for the past 15 years... because yep, everything circles back to CO2. Even when we really wish it didn't.

Looking forward to reading.

High-resolution Holocene record based on detailed tephrochronology from Torfdalsvatn, north Iceland, reveals natural and anthropogenic impacts on terrestrial and aquatic environments Abstract. Open questions remain around the Holocene variability of climate in Iceland, including the relative impacts of natural and anthropogenic factors on Late Holocene vegetation change and soil e...

New paper on Iceland! Over the last 20+ years, we've analyzed a bunch of high-resolution datasets from a small lake first studied in the early 90s. If you're interested in Holocene climate, tephra, algal pigments, and Norse settlement, this one might be for you: cp.copernicus.org/articles/21/...

Exciting!

One week left for US researchers and practitioners to respond to the call for experts for the IPCC Seventh Assessment Report!

🚨Calling U.S.-based climate experts! The newly formed U.S. Academic Alliance for the @ipcc.bsky.social is now accepting nominations for the Seventh Assessment Report.🌍

Join a global network of scientists shaping the future of climate action.

Apply by April 4: buff.ly/hDrBH1F

#IPCC #AGU

We want to hear from current and former federal workers from New England Are you a current or former federal worker in New England affected by the changes being made by the Trump administration? If you're willing to share your experience, we want to listen.

The conversations we've had with workers have helped us explain how the layoffs will affect Americans in New England and beyond.

Thank you!! I hadn’t and will check it out.