The green past of the Saharo-Arabian Desert: Isotope analyses of limestone cave deposits reveal recurrent humid intervals in the #SaharoArabianDesert over the last eight million years / International research project led by the Max Planck Institute for Chemistry with participation of #MainzUniversity and Goethe University Frankfurt, supported by the Saudi Heritage Commission and the Ministry of Culture 👉 https://press.uni-mainz.de/the-green-past-of-the-saharo-arabian-desert/

#paleoclimate #hydroclimate #geochemistry #stalagmites #speleothems

Always a good day when friends have a good day! Out today in NATURE (!) from Monika Markowska - 8 million year record of recurrent humid phases in Arabia.

https://www.nature.com/articles/s41586-025-08859-6

#Quaternary #QuaternaryScience #speleothem #speleothems #palaeoclimate

Written in stone. When illuminated like this, it's easy to see how geologists can use rock formations growing in caves as archives of the past. Photo by T. Holmes. #caves #cave #utah #geology #earthscience #speleothems

#PaperClub is back for the start of 2025, and we're kicking off with Patterson et al (2024), who present a PCP-corrected stalagmite d18O record from Vietnam, spanning 45-4 ka. Interesting paper, and the whole 'PCP impacts on d18O' thing has been getting quite a lot of airtime in recent years. Hopefully without sounding like a hater, I remain a bit skeptical. In this instance, the model assumptions include a feeding stalactite drip rate of 1 drip/second, which seems too high for LGM (where PCP effect on the stal was greatest). For stalactite PCP to be recorded in a stalagmite, there must not be sufficient residence time for re-equilibration to occur. I would love to see a sensitivity test of the drip rate on the model.

Growth rates during the 'peak PCP' period were also extremely low (<5 um/yr), which suggests to me that growth was likely not continuous over the period. d18O vals were high, I assume there was greater opportunity for disequilibrium to drive the signal rather than PCP?

Anyway, I'm definitely no expert in d18O kinetics, and I'm looking forward to hearing the opinions of the group, and anyone else who has read the paper :) I am really happy to be wrong about this, as there are lots of clever people on the paper who know more than me about this stuff!

#Paleoclimate #Speleothems #speleology
https://www.nature.com/articles/s41467-024-53422-y

Box of rocks arrived for me today 😍 we will be taking these beauties to the Aus Synchrotron next month to get an idea if they might be suitable for #palaeofire research. Happily, these were collected by a friend of mine for her PhD, which means a potential collaboration with a friend (yay!), and the reuse of old samples rather than collecting new (double yay!).

#speleothems #palaeoclimate

We were very kindly invited to write a communication piece for #AGUPubs Eos magazine, to go along with our recent review paper. If you'd like a quick overview on using #speleothems for #palaeofire research, look no further!

https://eos.org/editors-vox/using-cave-formations-to-investigate-ancient-wildfires

#SciComm #AcWri #paleofire @Andbaker @unsw

Woohoo it's paper publishing day! So pleased to have this article out in the light of day, and published #OpenAccess in Reviews of Geophysics. We give you everything we know about #speleothems as #palaeofire archives, including tips on sample and site selection, and appropriate methods. We then sweeten the deal with four case studies.

This one was a huge team effort, and could not have been written without the involvement of all the co-authors (👋 @Andbaker).

#AcWri #Academia

There's something soothing about polishing rocks. Gave some samples a touch-up ahead of a trip to the Synchrotron next week for some fun on the XFM line. Look at the shine! #palaeoClimate #Speleothems #Stalagmites #AustralianSynchrotron #Shiny

And if anyone is interested in the world of caves, stalagmites and climate, here are the links to the whole of the session. Even if you aren't registered, I believe you can read the abstracts:

Online PP11B poster session:
Monday 08:00-09:00 (CST), Online
Schedule: https://agu.confex.com/agu/fm22/meetingapp.cgi/Session/174723

In person PP22A oral session:
Tuesday 09:00-10:30 (CST), McCormick Place - S405a (South, Level 4)
Schedule: https://agu.confex.com/agu/fm22/meetingapp.cgi/Session/174716

In person PP25C poster session:
Tuesday 14:45-18:15 (CST), McCormick Place - Poster Hall, Hall A (South, Level 3)
Schedule: https://agu.confex.com/agu/fm22/meetingapp.cgi/Session/158058

#AGU22 #caves #stalagmites #speleothems #climate #geochemistry #isotopes

Working with #speleothems, #cave deposits or other #karst records? Come to our session at #EGU23 - Abstract submission is open!!!! All modern or paleo studies welcome… https://meetingorganizer.copernicus.org/EGU23/session/45507 @EuroGeosciences

My #firstpost on #Mastodon:

🌏 🌊 I am an Earth/climate scientist at the University of Arizona in #Tucson (southwestern US) focusing on the areas of #climate change, #paleoclimates, and #paleoceanography, with an emphasis on #ENSO, #monsoons, & #variability.

⚗️🐚 Our group uses #inorganic #geochemistry incl. measurements of #stableisotopes & #tracemetals in #carbonate rocks & #fossils (e.g., #foraminifera, #mollusks, & #speleothems) alongside climate #observations as well as #simulations to advance understanding of how the Earth's #climate & #oceans have changed in the past and can change in the future.

Some of my hobbies include:

🎵 #music: I am a fan of #metal and heavy music of all sorts, but tend to migrate towards #black, #death, #doom, #drone, #sludge, & #thrash. I also have a soft spot for #carnatic/#hindustani #ragas, #darkambient, oldschool-ish #hiphop, #triphop, and various forms of #electronicmusic.

🦜 #birds & #birding #photography bring me joy. Right now, I feel v lucky to be briefly back in my hometown of #Bengaluru, southern India, after three long years being able to see #oldworld birds I grew up with.

👨🏾‍💻 #GTD, #mindfulness, #organization, and (vs?) #producivity are things that I enjoy thinking about. Of late, I've been using #Things3, #Streaks, #Hobonichi w a #Lamy Safari, #Obsidian, #Overleaf, & #Bookends to get things done.

🙏🏽 Thanks for reading!