I worked with a great team of collaborators to produce a uniquely long #paleoclimate record from #caves in northern #utah. We dated stalagmites to show that mountain #permafrost repeatedly expanded during glacial periods and disappeared during interglacials in sync with orbital climate cycles over the past ~600,000 years. These results provide rare long-term constraints on alpine permafrost sensitivity and help place modern permafost thaw into a deeper climatic context. The paper was published in Quaternary Research; if you do not have access and wish to get a copy, feel free to send me a private request.

https://doi.org/10.1017/qua.2026.10076

#geology #climate #cave #caves #mountain #mountains #quaternary

New 46000-year record of the southern margin of the Indo-Australian Summer Monsoon just dropped from deadset legend Teresa Dixon at UQ.

#AusQuaternary #Monsoon #paleoclimate

https://www.sciencedirect.com/science/article/pii/S0031018226001410?via%3Dihub

Toll!
7.2mio Jahre alter Oberschenkel einer "Frau" wurde in Bulgarien gefunden. Der Oberschenkelhals und die Ansätze von schweren Gesäßmuskeln lassen auf den aufrechten Gang schließen.

Erwähnt außerdem: den 11mio Jahre alten Schwaben Udo, ein Danuvius guggenmosi , der auch schon aufrecht gehen konnte, und stellt die Bulgarin als Bindeglied zwischen Udo und den ersten, sehr viel jüngeren Funden aus Ostafrika dar.
Auch Klima wird erwähnt. Die große Abkühlung, die vor 15mio losging, hat Bulgarien vor ca 6mio Jahren regelrecht verwüstet und so migrierten Säugetiere, auch diese Oberschenkel... ^^, nach Süden, nach Afrika.

Meine Ergänzung:
in Schwaben war es da schon nicht mehr warm genug. Udo hatte vor 11mio Jahren zwar noch in Afrikanischer Pflanzenwelt gelebt, aber vor 6mio Jahren war es in Schwaben lokal halt schon ca. 20Grad kälter und auch die Alpen wölbten sich nach oben, was den Einfluss vom tropischem Mittelmeer/Afrika senkte.

hach.

Jetzt hätt ich gern noch die Einordnung, dass Afrika von 11 bis 7mio Jahre sowieso viel zu heiß gewesen ist, um große Säugetiere und aufrechtgehende Oberschenkel ^^ einen Lebensraum zu bieten.
Und dass nämlich darum die Wiege der Menschheit gerade nicht in Süd oder Ostafrika stand, sondern in Schwaben!!

https://nachrichten.idw-online.de/2026/03/04/stammt-der-aelteste-vorfahr-des-menschen-vom-balkan-ein-neues-fossil-schliesst-eine-luecke

#paleoclimate #paleontology #Klimawandel #Evolution

Mawbey et al 2026
https://www.nature.com/articles/s41467-026-68949-5
say that #WAIS retreat during the last deglaciation followed warmer seawater and not a warming air temperature.
On an unrelated matter, parts of their figure 3 caught my eye.
Especially the "ACR", Antarctic cold reversal pencilled in where it is.
For air temperature on the ice at WAIS, this cooling ACR began in 14.2ky BP (before present= before 1950).
But at that time, sea surface temperature had already cooled for 600 years or so.

Why did it catch my attention? Because this timing coincides nicely with the 2 locations I picked and plotted from Peltier's ice model https://www.atmosp.physics.utoronto.ca/~peltier/data.php

To investigate my idea of AMOC having two arms which do not stop at the same time, I picked a location in East Canada, Ungave Bay, and #Scotland on the other side of the #Atlantic.
What I found was indeed: East Canada experienced the cooling from the halted AMOC first and it took Scotland 1 time step longer to start regrowing its ice shield, suggesting that the Eastern arm of the #AMOC continued for quite a while longer when the Western arm had already stopped.

Timing:
14.8 ky
Sea surface temperature drops in Amundsen Sea
14.5 ky
Ungave Bay 🇨🇦 refreezes
14.2 ky WAIS air temperature drops
14 ky Scotland refreezes.

With the exception of WAIS air °C, the time resolution isn't definitive enough to answer this question – but it is an intriguing one:
what really came first? The warming of the Antarctic (lower ocean level) waters? Or the AMOC stop in its Eastern arm? 🐓 🥚
Antarctic circumpolar current is part of the AMOC – or vice versa. Antarctic bottom water formation is part of the AMOC. And they influence each other. So...

#paleoclimate #ocean #ice #climatechange

RE: https://aus.social/@Andbaker/115851475839893821

A reminder, American Geophysical Union honours nominations are open at the moment! The AGU Paleoceanography and Paleoclimatology section have three Honours available, for all career stages. Do you know of any AGU paleoclimate section members who could be nominated? Please share... #geology #Earthscience #paleoclimate #Paleoceanography

A new web interface for Berger et al's insolation calculator has been released. Check it out!

#ClimateChange #Paleoclimate

https://django.elic.ucl.ac.be/berger/insolation/

New paper out today by my #MPIC colleague (and officemate/friend) Sam Nicholson, who looked at the climatic constraints on speleothem deposition in SW Asia - to the surprise of no-one who spends any time thinking about speleothem deposition, it's not straightforward!

https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G54103.1/723985/The-climatic-constraints-on-speleothem-deposition

#speleothem #Karst #paleoclimate #geology

You et al investigate the Younger Dryas period both via proxy records and model simulations. They find that two phases of freshwater input from ice sheets are necessary to explain the sustained period of weak AMOC. https://doi.org/10.1126/sciadv.adv6220

This paper by You et al uses the PaleoMIST topography reconstruction for the modelling. I'm hopeful to have a new version out this year!

#ClimateChange #AMOC #PaleoClimate