Well, I've seen the aurora in Greenland, Svalbard and Alaska, but never before in Copenhagen (even though I tried at least 30 times). But tonight, I was lucky. Between 22.15 and 22.30 not to the north, but rather almost above me.

These are the icy mountains of Pluto. It took 9 years to get these magnificent images… and 4.8 billion kilometers.

En lille griner i en mørk tid

Kalaallit Nunaat Kalaallit pigaat (Greenland is the property of the Greenlanders)

The #PolarPortal seasonal report for 2024/2025 can now be downloaded. As always, in English, Danish and Greenlandic! See polarportal.dk/en/news/tran.... (Photo credit: @ruthmottram.bsky.social, DMI)

A Black man was killed by ICE (off duty) in Los Angeles on New Year’s Eve. And like Renée Good, he was an American citizen. But most people have not heard about Keith Porter. I need y’all to realize this. Black people experience this lack of visibility all the time when it comes to being victims.

Cold winter weather in Europe is coming to an end on Monday.

New podcast: Why does America want Greenland? Resources, strategy and network cities with @ruthmottram.bsky.social, @martinstendel.bsky.social, and Greenlander Anne Merrild open.spotify.com/episode/66gW...

Map of the Epstein files

Den grønlandske regering har ikke brug for rådgivning, heller ikke fra mig. Men ville man spørge mig alligevel, ville jeg anbefale at parkere en tankvogn fyldt med kerosin midt på runway i Nuuk hver nat. En flyver med marines, og det hele er forbi, før vi kan sige "f*ck, hvad er det?".

To cite the president whose name I cannot remember, closing down NCAR will be yet another step towards the United Sh*tholes of America.

Finally, here it is. Also this year, I have together with @ruthmottram.bsky.social commented on the fate of the Greenland Ice Sheet. Thanks for your patience, @carbonbrief.org. One of the highlights: 2024/25 was the 29th year in a row with net mass loss. See www.carbonbrief.org/guest-post-h...

Africa seen by African journalists. Highly recommended!

New GRACE data available on the Polar Portal. From April 2002 to July 2025, the Greenland Ice Sheet has lost roughly 5200 gigatonnes (=km³). This has contributed 1.5 cm to global sea level rise and would be enough to cover Denmark with 121 m of water. polarportal.dk/en/greenland...

Hurricane Melissa, an extremely dangerous category 5 hurricane with a core pressure of 892 hPa (rank 3) and maximum sustained winds of 295 km/h (also rank 3) just before landfall on Jamaica's south coast. After crossing the island, it will also hit eastern Cuba. Note that one can see "down" the eye.

Not extremely convincing, but I managed to see comet Lemmon. All photos with my Samsung S22, night mode, three minutes exposure.

151 years and almost 9 months of daily maximum temperatures in Copenhagen, 1874-2025! Green line: daily average Light blue/orange: 10 and 90 percentiles Blue/red: absolute lowest and highest maximum Purple: values for 2025. Grey: all other years Warm mid-September exceeding the old record from 1947.

Trump just designated “Antifa” as a terrorist organization, on par with ISIS and Al Qaeda. As a reminder, “antifa” is short for “antifascist”. They will use this lie to surveil, imprison, and kill Americans on the left. This may be our Reichstag Fire moment. Wake up. www.cnn.com/2025/09/17/p...

Mondfinsternis - Lunar eclipse - Måneformørkelse

Things were easier in 1954 when meteorologists still wore ties.

Accumulated surface mass balance (SMB) 1 Sep 2024 to 31 Aug 2025 was 403.8 Gt (=km³), close to the average 1980-2025. SMB is snowfall - runoff, i.e. always positive. This is NOT the total mass balance TMB, which also includes iceberg calving and which shows ice loss for the 29th year in a row.

Components of the total mass balance TMB, hydr. years 1987-2025: SMB: surface mass balance (snowfall-runoff), MMB: marine mass balance (calving of icebergs), BMB: basal mass balance (friction). 2024/25: the 29th year in a row with negative TMB. Update of Mankoff et al. (2021), tinyurl.com/295khdnk.

As it is quite probable that at the end of the week it turns out that it is worth starting a war of aggression, I asked Gemini to give me a map of Europe showing Putin's next desires (i.e., all countries bordering either Russia or Belarus). I must say the result is pretty convincing.

Sehr cool. www.chronotrains.com/de/explore/2...

Melting over 80.6% of the area of the Greenland Ice Sheet. This is the highest value in our data set, which starts in 1981. @polarportal.bsky.social

Extreme Greenland melting event right now: thawing over 80% of the surface. Seen before only once in the record melt summer 2012. See more at @polarportal.bsky.social!

PLEASE NOTE: Data source for sea ice concentration and extent has changed. Beginning 1 July 2025, the Japanese AMSR2 is replacing the US SSMIS instrument for our sea ice concentration and extent products. SSMIS and AMSR2 differ by ±0.1 million km² or less with larger differences in summer.

If there is one graph showing the effect of human activities on the atmosphere, it is the Keeling curve, which shows the concentration of CO₂ since 1958. Mauna Loa Observatory captured the reality of climate change. The US plans to shut it down theconversation.com/mauna-loa-ob...

Lennart Bengtsson, former director of the ECMWF and the Max Planck Institute for Meteorology, the father of reanalyses and the ECHAM climate model and my boss from 1994 to 1998, has turned 90. mpimet.mpg.de/en/communica...

Flere vil dø på grund af vejrhændelser på grund af besparelser i vejrtjenesten: hurricane-sæson er lige begyndt. www.dr.dk/nyheder/udla...

More people to die soon?

This will cost the GOP the midterm election. If there is an election.

151½ years of daily maximum temperatures in Copenhagen, 1874-2025! Green line in the middle: daily average Light blue/orange: 10 and 90 percentiles Blue/red: absolute lowest and highest maximum Purple: values for 2025. Grey: all other years Note the "heat wave" 4 to 8 March, 10°C above the average!

As a German I ask: what is the difference between this and a concentration camp?!

𝐈𝐌𝐏𝐎𝐑𝐓𝐀𝐍𝐓 𝐍𝐎𝐓𝐄: The access to SSMIS data  from the US DMSP satellites is coming to an end. 𝐓𝐡𝐞 𝐚𝐜𝐜𝐞𝐬𝐬 𝐭𝐨 𝐝𝐚𝐭𝐚 𝐰𝐢𝐥𝐥 𝐞𝐧𝐝 𝐚𝐥𝐫𝐞𝐚𝐝𝐲 𝟑𝟎 𝐉𝐮𝐧𝐞 𝟐𝟎𝟐𝟓. We are working on the matter and try to find a replacement.

So far this week: ❌ SSMIS data halted (think sea ice, snow, hurricane, ice sheet monitoring, etc) ❌ climate[dot]gov removed and redirected to... ❌ NOAA Climate homepage, which was modified (e.g., removed Climate Stripes and Climate Ready Nation references) ❌ false bills to ex-probationary employees

This is very bad news. #Arctic #SeaIce @zacklabe.com @climatologist49.bsky.social

Ablation season in Greenland has begun, almost on date.

Shouldn't have fired the NOAA people. But in everything, there's something good - he admitted having had a poor attendance.

Jeg håber virkelig, at I ved, hvad I sætter i gang.

Progress in ROPEWALK, our large ship journal digitisation project! @adamjonk.bsky.social #esben_haubro_skov @dmidk.bsky.social #Rigsarkivet

Watch this. And listen.

It is not only the models, but also the observations behind them. As @michaelrlowry.bsky.social explains, these forecasts cost every US citizen $4 per year, but the profit (avoidance of losses) amounts to $320. We'll, it won't be Musk and consorts who'll die in one of the next hurricanes, I assume.

I cannot believe this is true. If at all possible, come and join us in Europe!

News from a "third world" country.

Never forget: today 8 years ago

“A developed country is not a place where the poor have cars. It's where the rich use public transportation.” – Former Bogotá Mayor Enrique Peñalosa.

Damn autopilot...

Next step in the ROPEWALK project: Quality control of the many ship voyages. A common problem is with position, both in the original (e.g., wrong octant near the prime meridian) and the transcribed data. Next, search for outliers etc. will be done. Example: M/S Uruguay, first quarter of 1952.

Unseasonally warm over eastern Greenland and Iceland. Egilsstaðaflugvöllur in eastern Iceland had a maximum temperature of 26°C, while a maximum of 14°C was observed in Ittoqqortoormiit in eastern Greenland. That is about 10°C warmer than the average temperature for the time of the year.