Alex Auderset

Persistent eastern equatorial Pacific Ocean upwelling since the warm Pliocene Upwelling generates a nutrient-rich “cold tongue” in the eastern equatorial Pacific Ocean (EEP), with impacts on global climate, oceanic biological productivity, and the carbon cycle. The cold tongue ...

Today, we published a study long in the making on how upper and subsurface tropical Pacific waters responded (and maybe will adjust) to warmer global climate. Here’s the story of how we got here after 15 years. many authors but shout out @jfarmersalmanac.bsky.social
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www.science.org/doi/10.1126/...

Very excited to be a part of this epic journey with @oceanandclimate.bsky.social. Check out our #NSFfunded paper published in @science.org today & his thread below. After that, come back here for more... (1/n)

Nevertheless, this new approach to studying symbiosis offers a novel pathway to reconstruct paleo-symbiosis in extinct foraminifera—an essential piece of information for interpreting numerous geochemical proxies.

However, we also show that this relationship can be more complex in regions with strong environmental gradients, where additional factors influence nitrogen isotopes.

In this study we show that foraminifera-bound nitrogen isotopes (FB-δ15N) distinguish between symbiont-bearing and symbiont-barren foraminifera. FB-δ15N shows a clear signal of dinoflagellate symbiosis and may even identify other symbionts like chrysophytes or pelagophytes.

Nitrogen isotopes are a promising tool to reconstruct symbiosis in planktic foraminifera!
Check out our latest paper:
bg.copernicus.org/articles/22/...

In this study we show that foraminifera-bound nitrogen isotopes (FB-δ15N) distinguish between symbiont-bearing and symbiont-barren foraminifera. FB-δ15N shows a clear signal of dinoflagellate symbiosis and may even identify other symbionts like chrysophytes or pelagophytes.

Sea Level Modulation of Atlantic Nitrogen Fixation Over Glacial Cycles Reduction of nitrogen fixation in the Atlantic Ocean during ice ages, proportional to sea-level variations in regional shelf area Regional coupling between nitrogen fixation and shelf sedimentary...

Nitrogen isotope paper published in Paleoceanography and Paleoclimatology, go check it out :)
doi.org/10.1029/2024...

Packed room at EGU for @alexauderset.bsky.social talk on ocean deoxygenation in past warm climates!

If you plan to go to Goldschmidt this year, please consider submitting an abstract to our Session 13g!
Keynote speaker: Sze Ling Ho (National Taiwan University)
Deadline approaching fast: 29th of March

conf.goldschmidt.info/goldschmidt/...

Just published in Science! Our new study shows an oxygen increase in the tropical subsurface ocean during the PETM, reconstructed by foraminifera-bound nitrogen isotopes (FB-d15N) and a foraminiferal body size model (FS-pO2).

Check out the paper:
www.science.org/doi/epdf/10....