Abrupt Antarctic Sea-Ice Collapse & Increased Saltiness Regime Change: More Observations & Analysis

Abrupt Antarctic Sea-Ice Collapse & Increased Saltiness Regime Change: More Observations & Analysis Please donate to http://PaulBeckwith.net to support my research and videos connecting the dots on abrupt climate system mayhem. Article from "The Conversation": ‘Completely unexpected’: Antarctic sea ice may be in terminal decline due to rising Southern Ocean salinity https://theconversation.com/completel... Figures on Antarctic Ocean warming, from latitude 50S to 65S, for various regions around the continent: https://www.nature.com/articles/s4146... Earth Nullschool depiction of ocean surface currents: https://earth.nullschool.net/#current... Labelled map of the various oceans around Antarctica: https://www.coolantarctica.com/galler... Bulletin of the American Meteorological Society (BAMS): Title: ANTARCTICA AND THE SOUTHERN OCEAN https://journals.ametsoc.org/view/jou... Peer-reviewed paper: Title: Southern Ocean warming and its climatic impacts Abstract The Southern Ocean has warmed substantially, and up to early 21st century, Antarctic stratospheric ozone depletion and increasing atmospheric CO2 have conspired to intensify Southern Ocean warming. Despite a projected ozone recovery, fluxes to the Southern Ocean of radiative heat and freshwater from enhanced precipitation and melting sea ice, ice shelves, and ice sheets are expected to increase, as is a Southern Ocean westerly poleward intensification. The warming has far-reaching climatic implications for melt of Antarctic ice shelf and ice sheet, sea level rise, and remote circulations such as the intertropical convergence zone and tropical ocean-atmosphere circulations, which affect extreme weathers, agriculture, and ecosystems. The surface warm and freshwater anomalies are advected northward by the mean circulation and deposited into the ocean interior with a zonal-mean maximum at 45S. The increased momentum and buoyancy fluxes enhance the Southern Ocean circulation and water mass transformation, further increasing the heat uptake. Complex processes that operate but poorly understood include interactive ice shelves and ice sheets, oceanic eddies, tropical-polar interactions, and impact of the Southern Ocean response on the climate change forcing itself; in particular, limited observations and low resolution of climate models hinder rapid progress. Thus, projection of Southern Ocean warming will likely remain uncertain, but recent community effort has laid a solid foundation for substantial progress. Link: https://www.sciencedirect.com/science... Peer-reviewed scientific paper: Title: Pacific sub-decadal sea surface temperature variations contributed to recent Antarctic Sea ice decline trend Abstract Total sea ice extent (SIE) across the Southern Ocean increased from 1979-2014, but declined rapidly after 2016. Significant sea ice decline has emerged since the peak of SIE in 2014, coincident with Pacific sub-decadal sea surface temperature (SST) trends resembling a strong La Niña-like cold condition and the negative phase of the interdecadal Pacific oscillation (IPO). Previous studies suggest that the warm subsurface Southern Ocean was an important driver of the low sea ice in spring 2016 and the sustained low sea ice state since. Here we show that the observed atmospheric circulation changes near Antarctica during the period from June 2013-May 2023 are conducive to increasing surface temperature via warm advection from north and reducing Antarctic SIE, involving a deepening of the Amundsen Sea Low and anomalous high pressures over the Weddell Sea and West Pacific sectors. Through coupled pacemaker experiments, we demonstrate that Pacific sub-decadal SST trends have dominantly driven these atmospheric circulation changes through tropical–polar teleconnections and also induced significant Southern Ocean subsurface warming in the recent decade. The consequent decreasing SIE has enhanced the Southern Ocean subsurface warming effect and significantly contributed to the rapid Antarctic SIE decline. Link: https://www.nature.com/articles/s4146... Article: Collapse of key Atlantic currents may be held off by newly-discovered back-up system, study finds: https://www.livescience.com/planet-ea... Peer-reviewed paper: Intensification and shutdown of deep convection in the Labrador Sea were caused by changes in atmospheric and freshwater dynamics Link: https://www.nature.com/articles/s4324... Please donate to http://PaulBeckwith.net to support my research and videos connecting the dots on abrupt climate system mayhem.