We’ve wrapped up drilling at Crary Ice Rise with 228m of sediment core. This is an unprecedented record of the history of the West Antarctic Ice Sheet stretching back millions of years. Initial observations indicate the core includes periods of environmental change during past times of warming.
🚨job opportunity🚨
Durham is advertising 3-year fellowships (any field). We are very keen to hear from Antarctic/Cryo people who might be interested in joining a great group. The positions come with some travel & research funds. See here for details or get in touch www.durham.ac.uk/research/ins...
A couple of take home messages. First, and perhaps uncontroversially (!?), is that ice in the Amundsen Sea retreats when warm water is circulating on the shelf and stops retreating when heat is reduced. Probably not as simple as turning CDW on/off and might relate to the depth of the thermocline 🧵⬇️
This was justifiably questioned during the review process, but I think we addressed it well. Ultimately any single location in the Amundsen Sea – below a certain water depth - is likely to be representative (in the broadest terms) of the entire shelf 🧵⬇️
Furthermore, the time required to fully replace water properties following a regime shift, is a few years for small shelf seas like the Amundsen Sea (Nakayama et al. doi.org/10.1002/2014...) and up to a few decades for larger ones such as the Weddell (Naughten et al. www.nature.com/articles/s41...)
Pleased to see this finally out, involving a brilliant team @emawbey.bsky.social, @erinmcclimate.bsky.social, @krhendry.bsky.social, @polarrobs.bsky.social, @wellner.bsky.social, supported by @bas.ac.uk, @awi.de , @geogdurham.bsky.social and #Thwaites🧵⤵️
www.nature.com/articles/s41...
Second, this type of work is really hard, just ask @emawbey.bsky.social who spent years (literally) sifting through sand grains looking for forams! Along with colleagues from @awi.de and the US, we’ve collected >400 cores from the Amundsen Sea and only a handful contained enough forams for Mg/Ca 🧵⬇️
Even when we found cores that contained enough of these tiny fossils, the temporal resolution was patchy or sometimes incomplete = 😭. This was painstaking and laborious and huge kudos to @emawbey.bsky.social for hanging on in there. However, because of this we used a multi-core approach 🧵⬇️
Amundsen Sea records show warm Circumpolar Deep Water drove major West Antarctic Ice Sheet retreat from 18,000–10,000 years ago. Subsequent cooling stabilized the grounding line, indicating ocean heat...
Congratulations to our colleagues @erinmcclimate.bsky.social and Charlotte Spencer-Jones on the publication of their co-authored article in Nature Communications ‘Ocean heat forced West Antarctic Ice Sheet retreat after the Last Glacial Maximum’: www.bas.ac.uk/news/warm-oc...
