Arctic News: Double Blue Ocean Event 2025?

Friday, October 4, 2024

Double Blue Ocean Event 2025?

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.

Trends could be added pointing at Arctic sea ice approaching zero volume soon; even more worrying, tipping points could be crossed and speed up the temperature rise beyond a smooth curve.

Currently, Antarctic sea ice extent is at its maximum for the year, in line with seasonal changes. Antarctic sea ice is now about 17 million square km in extent, much lower than it was a decade ago.

Global sea ice extent is now several million square km lower than it was decades ago.

There are indications that sea ice volume is already decreasing, as illustrated by the images by University of Bremen below shows sea ice volume at August 27, 2024 (left), and September 29, 2024 (right).

On February 16, 2023, Antarctic sea ice extent was 1.95 million square km.

There are at least seven mechanisms causing surface temperatures to rise, accelerating sea ice decline, as follows:

1. latent heat buffer loss ➭ less heat gets consumed by melting

2. sea ice changing into dark ocean ➭ less sunlight is reflected

3. less sea ice ➭ less outward radiation

4. ocean warming ➭ less lower clouds ➭ less sunlight reflected

5. ocean warming ➭ stratification ➭ less heat reaches deeper waters

6. ocean currents and wind patterns change ➭ less heat reaches deeper waters

7. freshwater lid forms at ocean surface ➭ more heat reaches Arctic Ocean

The black dashed line in the image below, adapted from NOAA, indicates a transition to La Niña in October 2024, persisting through Jan-Mar 2025.

A new El Niño could emerge in the course of 2025, while sunspots reach a peak in this cycle (expected to occur in July 2025), adding further heat.

As temperatures keep rising, this could cause a second Blue Ocean Event to occur in 2025, I.e. in the Arctic. Subsequently, as the oceans keep heating up, the seafloor methane tipping point could be crossed. The danger is that a cascade of events will unfold like a domino effect, leading to extinction of most species, including humans, as the image below warns.

[ from earlier post - click on images to enlarge ]

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.