#paleoclimate — Public Fediverse posts

Still haven't gotten around comprehending how to convert a lat-lon grid with ice thickness to a correct regional sum of freshwater amount in Gt.

But something else keeps popping up in my head now.
Peltier's ice model / reconstruction (dunno which it is) doesn't include sea ice at all https://www.atmosp.physics.utoronto.ca/~peltier/data.php

Tarasov's GLAC1D model does. https://doi.org/10.5281/zenodo.10159104
At least the melted parts of sea ice is included. But not the ever-lasting part.

That ever-lasting part is melting today, and has been melting for a long while now. But it didn't melt during past AMOC hickups. What melted back then was ice that covered Scotland with a whopping 400m ice wall. And higher ice mountains still melted in other regions. But not sea ice in the Arctic ocean.

...hm. What I really want to know is how the amount of freshwater influx back then
compares to the amount today, and how today's very little left-over ice would be capable of stopping AMOC.

We'll be having a blue Arctic ocean before 2030, says a new study https://www.ft.com/content/63fbcf2b-9acc-4ccb-ac12-9f3b78e85b68

https://www.nature.com/articles/s41467-024-54508-3 #Heuze and #Jahn 2024, "The first ice-free day in the Arctic Ocean could occur before 2030" #openaccess 💃

Wouldn't it be cool to know by then how much ice in kilos or Gt melted ? And how that amount compares to the amount before previous AMOC shutdowns during the LGM and deglaciasation?

#paleoclimate #sealevelrise #GlacierMelt #AMOC #seaice #Arctic

#AskFedi

Who knows what the meltrate was in Gt, the Atlantic freshwater input per year (or 100yrs) in paleoclimate, before an AMOC stop or strong slowdown?

Glacier and sea ice from East Canada and West Greenland, and on the other AMOC limb, NE-Greenland with Scandinavia and the British isles.

I would like to be able to compare today's melt rate to past incidents of ice melt and AMOC slowdown / stop.
And to be able to plot data along other proxy time series to get a feel for things.

Today's data is given in Gt. So that's what I'd be after in paleoclimate data. Sverdrup is not so useful to me.

Today's Greenland melt can be 444 Gt yr in 2019 as per https://essd.copernicus.org/articles/15/1597/2023/ by #Otosaka etal 2024
and on average 270 Gt/year as per State of the Cryosphere Report https://iccinet.org/statecryo24/ , based on #Greene etal 2024.

Thank you for sharing my question🙏! And for pointers!

#AMOC #paleoclimate #seaice #glacier #GlacierMelt #Atlantic
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