5 months ago
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A double Blue Ocean Event could occur in 2024. Both Antarctic sea ice and Arctic sea ice could virtually disappear in 2024. A Blue Ocean Event (BOE) occurs when sea ice extent falls to 1 million km² or less, which could occur early 2024 for Antarctic sea ice and in Summer 2024 in the Northern Hemisphere for Arctic sea ice.
Antarctic sea ice loss
The situation regarding Antarctic sea ice extent is pictured in the image below, which shows that on December 12, 2023, Antarctic sea ice extent was 9.499 million km², a record low for the time of year.
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| [ image adapted from NSIDC ] |
Antarctic sea ice extent was 1.788 million km² on February 21, 2023. Antarctic sea ice extent may well be much lower in February 2024, with sea ice loss fuelled by several self-reinforcing feedback loops, as discussed in an earlier post.
Arctic sea ice loss
The situation regarding Arctic sea ice extent is pictured in the image below.
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| [ image adapted from NSIDC ] |
The above image shows that on December 12, 2023, Arctic sea ice extent was 9.499 million km², third lowest low for the time of year, behind 2016 and 2020.
The situation is dire
On December 12, 2023, as said, Arctic sea ice extent was 9.499 million km², third lowest low for the time of year, i.e. only 2016 and 2020 were lower. The years 2016 and 2020 had the highest annual temperature (a tie) on record and this annual temperature record is likely to be surpassed in 2023, while 2024 may be even worse, as the chance that the current El Niño will slow down soon is minimal.
Arctic sea ice extent would have been even lower, had the Atlantic meridional overturning circulation (AMOC) not been slowing down. As a result of AMOC's slowing down, less ocean heat is reaching the Arctic Ocean. Instead, a huge amount of ocean heat has been accumulating in the North Atlantic and much of this heat could soon be pushed abruptly into the Arctic Ocean as storms temporarily speed up currents that carry ocean heat into the Arctic Ocean.
Furthermore, Earth's radiation imbalance is very high, emissions are high and rising, and politicians refuse to act responsibly, all contributing to further deteriorate the situation, with the danger that ocean heat will reach and destabilize methane hydrates that are contained in sediments at the seafloor of oceans, resulting in massive methane eruptions, as discussed in many earlier posts such as this one.
Climate Emergency Declaration
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 combined with a Climate Emergency Declaration as discussed at this group.
