This post from Morganism on another page seems relevant to the conversation.
How melting Arctic ice leads to European drought and heatwaves
Fresh, cold water from Greenland ice melting upsets North Atlantic currents.
The Arctic Ocean is mostly enclosed by the coldest parts of the Northern Hemisphere’s continents, ringed in by Siberia, Alaska and the Canadian Arctic, with only a small opening to the Pacific through the Bering Strait, and some narrow channels through the labyrinth of Canada’s Arctic archipelago.
But east of Greenland, there’s a stretch of open water about 1,300 miles across where the Arctic can pour its icy heart out to the North Atlantic. Those flows include increasing surges of cold and fresh water from melted ice, and a new study in the journal Weather and Climate Dynamics shows how those pulses can set off a chain reaction from the ocean to the atmosphere that ends up causing summer heatwaves and droughts in Europe.
The large new inflows of fresh water from melting ice are a relatively new ingredient to the North Atlantic weather cauldron, and based on measurements from the new study, a currently emerging “freshwater anomaly” will likely trigger a drought and heatwave this summer in Southern Europe, said the study’s lead author, Marilena Oltmanns, an oceanographer with the United Kingdom’s National Oceanography Centre.
She said warmth over Greenland in the summer of 2023 melted a lot of ice, sending more freshwater toward the North Atlantic. Depending on the exact path of the influx, the findings suggest that, in addition to the immediate impacts this year, it will also trigger a heatwave and drought in Northern Europe in a more delayed reaction in the next five years, she said.
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The coming extremes will probably be similar to the European heatwaves of 2018 and 2022, she added, when there were huge temperature spikes in the Scandinavian and Siberian Arctic, as well as unusual wildfires in far northern Sweden. That year, much of the Northern Hemisphere was scorched, with “22 percent of populated and agricultural areas simultaneously experiencing heat extremes between May and July,” according to a 2019 study in Nature.
(more)
https://arstechnica.com/science/2024/03/how-melting-arctic-ice-leads-to-european-drought-and-heatwaves/#p3European summer weather linked to North Atlantic freshwater anomalies in preceding years
Amplified Arctic ice loss in recent decades has been linked to the increased occurrence of extreme mid-latitude weather. The underlying mechanisms remain elusive, however. One potential link occurs through the ocean as the loss of sea ice and glacial ice leads to increased freshwater fluxes into the ocean. Thus, in this study, we examine the link between North Atlantic freshwater anomalies and European summer weather. Combining a comprehensive set of observational products, we show that stronger freshwater anomalies are associated with a sharper sea surface temperature front between the subpolar and the subtropical North Atlantic in winter, an increased atmospheric instability above the sea surface temperature front, and a large-scale atmospheric circulation that induces a northward shift in the North Atlantic Current, strengthening the sea surface temperature front. In the following summer, the lower-tropospheric winds are deflected northward along the enhanced sea surface temperature front and the European coastline, forming part of a large-scale atmospheric circulation anomaly that is associated with warmer and drier weather over Europe. The identified statistical links are significant on timescales from years to decades and indicate an enhanced predictability of European summer weather at least a winter in advance, with the exact regions and amplitudes of the warm and dry weather anomalies over Europe being sensitive to the location, strength, and extent of North Atlantic freshwater anomalies in the preceding winter
https://wcd.copernicus.org/articles/5/109/2024/
