Sea ice alert

1 month ago 21

[ click on images to enlarge ]

Arctic sea ice extent was very low during the period from October 14 to November 7, 2024. It was lower only on some days during this period in 2016, 2019 and 2020, as illustrated by the above image.

The recent slow growth of Arctic sea ice extent is remarkable. When slow growth occurred in 2016 and in 2019, El Niño conditions were prominent. Higher than usual temperatures during El Niño years typically slow down Arctic sea ice extent growth at this time of year. By contrast, La Niña conditions were prominent since October 2024. It is remarkable for slow growth to occur during La Niña conditions in 2024.

The image below highlights Antarctic sea ice extent during the months September and October, showing NSIDC data from 2010 through November 2, 2024.

[ from earlier post ]

As illustrated by the above image, Antarctic sea ice extent in September and October 2023 & 2024 was much lower than in previous years, a huge difference that occurred during a period when little or no sunlight was reaching Antarctic sea ice.

Global sea ice typically reaches its annual maximum extent around this time of year, as Arctic sea ice expands in extent.

On November 3, 2024, global sea ice extent was 23.15 million km², a record low for the time of year and well below the 2023 extent at this time of year.

[ from earlier post ]

Higher ocean heat in combination with higher air temperatures over the Arctic Ocean are two drivers behind the slow growth in Arctic sea ice extent. The image below shows high temperatures over the Arctic Ocean on November 5, 2024, 00Z.

High temperature anomalies are in turn resulting in high anomalies in precipitable water, as illustrated by the image below.

There are many feedbacks and other mechanisms active and they are interacting on top of driving up temperatures individually. Albedo change is a feedback that can have a huge impact. The record low global sea ice extent is accelerating the rise in global temperatures, as it results in less sunlight getting reflected back into space and more heat getting absorbed by oceans.

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 in combination with a Climate Emergency Declaration, as discussed at this group.