Arctic sea ice volume
In September 2024, Arctic sea ice reached a new record low volume, as illustrated by the image below, adapted from the Danish Meteorological Institute, with markers for September (red) and April (blue) corresponding with the year's minimum- and maximum volume.
Indeed, some mechanisms can have a more abrupt impact. Sea ice could shrink strongly and rapidly as a (tipping) point is reached where the latent heat buffer disappears abruptly and as further incoming ocean heat suddenly can no longer be consumed by melting of what once was thick sea ice that extended meters below the surface. Arctic sea ice typically reached its annual low about half September, but an abrupt decline of Arctic sea ice may well occur earlier than that. Sea ice may melt strongly, and large pieces of sea ice may additionally get pushed out of the Arctic Basin by strong winds. Large and rapid loss of Arctic sea ice may therefore well occur in July 2025 or even earlier, as the latent heat tipping point gets crossed and additional mechanisms further contribute to increase the temperature.
On October 11, 2024, Antarctic sea ice was more than 1 million km² lower in extent than on October 11, 2022, and almost 3 million km² lower in extent than a decade ago, as illustrated by the image below.
This difference indicates that extent may fall below 1 million km² in February 2025.
Antarctic Sea ice thickness and volume
There are indications that Antarctic sea ice volume is already decreasing. The images by University of Bremen below show sea ice thickness on August 27, 2024 (left), September 29, 2024 (center) and October 5, 2024 (right).
Temperatures keep rising
The image below, based on ERA5 data from early 2023 through October 8, 2024, indicates that temperature anomalies have been rising since the start of El Niño, a rise that has continued during ENSO-neutral conditions into La Niña.
Mechanisms accelerating the temperature rise
Higher sea surface temperatures come with greater stratification.
[ from earlier post ] |
[ from earlier post ] |
Polar amplification of the temperature rise causes a relative slowing down of the speed at which heat flows from the Equator to the poles. This impacts ocean currents and wind patterns, resulting in slowing down of the Atlantic meridional overturning circulation (AMOC) and of ocean currents around Antarctica that carry heat to the deep ocean, as well as in deformation of the Jet Stream.
A further mechanism that could strongly accelerate the temperature rise is the falling away of the masking effect of aerosols currently emitted jointly with the greenhouse gases produced in the process of burning fossil fuel and biofuel. Blunt measures may be taken to reduce burning of fossil fuel and biofuel, which will reduce greenhouse gas emissions and emission of cooling aerosols, while such measures can at the same time encourage many to use more wood burners, causing more emissions of warming aerosols. Sadly, few people are calling for more sophisticated measures.
The water feedback is also getting stronger. The image below, created with NOAA data, shows surface precipitable water through September 2024. Note that values in 2024 are higher than in 2023.
[ from earlier post - click on images to enlarge ] |
[ for more background, also view the Extinction page ] |
A huge temperature rise could occur soon, as the impact of these mechanisms keeps growing, as the latent heat tipping point gets crossed in a Double Blue Ocean Event and the seafloor methane tipping point subsequently gets crossed.
As temperatures keep rising in the Arctic, changes to the Jet Stream look set to intensify, resulting in loss of terrestrial albedo in the Arctic that could equal the albedo loss resulting from sea ice decline.
Further feedbacks include permafrost degradation, both terrestrial and on the seafloor of the Arctic Ocean, which looks set to cause huge releases of greenhouse gases (particularly CO₂, CH₄ and N₂O).
This would in turn also cause more water vapor to enter the atmosphere, further speeding up the temperature rise. Water vapor is getting very high, in part because the temperature may already have risen by more than what the IPCC wants people to believe.
The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.
• Arctic Data archive System - National Institute of Polar Research - Japan
https://ads.nipr.ac.jp/vishop
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php
• University of Bremen - Arctic sea ice
https://seaice.uni-bremen.de/start
• NSIDC - Interactive sea ice chart
https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph
https://www.facebook.com/groups/arcticnews/posts/10161543138459679
• NOAA - Climate Prediction Center - ENSO: Recent Evolution, Current Status and Predictions
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf
• NOAA - Physical Sciences Laboratory
https://psl.noaa.gov
https://arctic-news.blogspot.com/p/feedbacks.html
• Jet Stream
https://arctic-news.blogspot.com/p/jet-stream.html
• Freshwater lid on the North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html
• Latent Heat
https://arctic-news.blogspot.com/p/latent-heat.html
• Sunspots
https://arctic-news.blogspot.com/p/sunspots.html
• Pre-industrial
https://arctic-news.blogspot.com/p/pre-industrial.html
• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html
• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html
• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html