Friday, March 22, 2024

Atlantic ocean heat threatens to unleash methane eruptions

The image below shows that the monthly Atlantic surface temperature anomaly in February 2024 was 1.176°C when compared to a 1951-1980 base.

[ click on images to enlarge ]

The image below shows that the monthly Atlantic surface temperature anomaly in February 2024 was 1.435°C when compared to a 1901-2000 base. 


The difference illustrates the importance of selecting a base to calculate anomalies from. The anomaly indicates how much heat has accumulated in the Atlantic, and it is even larger for February 2024 when using a genuinely pre-industrial base, as discussed earlier.

The images also highlight the potential for the slowing down of the Atlantic meridional overturning circulation (AMOC) to contribute to more heat accumulating at the surface of the Atlantic Ocean.

As temperatures rise, many feedbacks are kicking in with greater ferocity, including increased stratification of oceans, loss of sea ice, loss of reflectivity of clouds and increased freshwater due to stronger melting of sea ice and glacial ice, due to heavier runoff from land and rivers and due to changes in ocean circulation.

While this may look to cause less ocean heat to reach the Arctic Ocean at the moment, the result is that a huge amount of ocean heat is accumulating in the North Atlantic that threatens to abruptly move into the Arctic Ocean. The danger is that an influx of ocean heat can cause large amounts of methane to erupt from the seafloor of the Arctic Ocean. 

The inset on the top image illustrates that, as people's emissions raise the temperature, this rise can strengthen wind, evaporation, ocean currents and rainfall locally, resulting in greater potential for a lid to form and spread at the surface of the North Atlantic. As temperatures rise and winds strengthen, more evaporation can occur in one place and more rain can then fall further down the path of the Gulf Stream, i.e. an ocean current that extends into the Arctic Ocean, as part of AMOC. This rain further contributes to the freshwater accumulation at the surface of the North Atlantic.

In the video below, Guy McPherson discusses a recent study by Marilena Oltmanns et al. on some of these issues.


This page further discusses formation of a cool freshwater lid at the surface of the North Atlantic and the contribution to this of Jet Stream changes. The image below shows that the Jet Stream reached speeds as high as 455 km/h or 283 mph north of Washington on February 18, 2024 03:00 UTC, with Instantaneous Wind Power Density as high as 387.5 kW/m².

From earlier post Blue Ocean Event 2024?

A huge amount of ocean heat is accumulating in the North Atlantic and threatens to abruptly move into the Arctic Ocean. The danger is that, due to strong wind along the path of the Gulf Stream, huge amounts of ocean heat will abruptly get pushed into the Arctic Ocean, with the influx of ocean heat causing destabilization of hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane. 

Strong hurricanes can significantly add to the danger. More hurricanes are forecast for the 2024 Atlantic hurricane season than during 1950-2020, as illustrated by the image below. 


Many of the dangers have been discussed before, e.g. the danger that sea currents in the Arctic Ocean will change direction, in this 2017 post

Arctic sea ice thickness warning

The compilation image below shows Arctic sea ice on March 28, 2024. The satellite image (left) may indicate extensive sea ice, but clouds can obscure things. The other image (right) indicates that sea ice in a large area from the Laptev Sea down to the North Pole may be very thin.


The image below illustrates the decline of Arctic sea ice volume over the years.


The images above and below show that Arctic sea ice volume has recently been the lowest on record for the time of year.


Given that Arctic sea ice currently is still relatively extensive, this low volume indicates that sea ice is indeed very thin, which must be caused by ocean heat melting sea ice from below, since little or no sunshine is yet reaching the Arctic at the moment and air temperatures are still far below freezing point, so where ocean heat may be melting sea ice away from below, a thin layer of ice will quickly be reestablished at the surface. 

This situation looks set to dramatically change over the next few months, as air temperatures will rise and as more ocean heat will reach the Arctic Ocean. Moreover, as illustrated by the map below, much of the thicker sea ice is located off the east coast of Greenland. This sea ice and the purple-colored sea ice can be expected to melt away quickly with the upcoming rise in temperatures over the next few months.


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.


Links

• Climate Reanalyzer

• Pre-industrial
https://arctic-news.blogspot.com/p/pre-industrial.html

• Cold freshwater lid on North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html

• European summer weather linked to North Atlantic freshwater anomalies in preceding years - by Marilena Oltmanns et al.
https://wcd.copernicus.org/articles/5/109/2024/wcd-5-109-2024-discussion.html
discussed at facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10161330866254679

• Science Snippets: Arctic Sea Ice Affects European Summers, Marine Life, and All Life on Earth - by Guy McPherson
https://www.youtube.com/watch?v=X09vtWNDuDw

• nullschool 
https://earth.nullschool.net

• Jet Stream
https://arctic-news.blogspot.com/p/jet-stream.html

• Extended range forecast of Atlantic seasonal hurricane activity and landfall strike probability for 2024 - by Philip Klotzbach et al.
https://tropical.colostate.edu/forecasting.html
discussed on facebook at:
https://www.facebook.com/groups/arcticnews/posts/10161346323759679

• Arctic Ocean Feedbacks
https://arctic-news.blogspot.com/2017/01/arctic-ocean-feedbacks.html

• NASA Worldview satellite images
https://worldview.earthdata.nasa.gov

• University of Bremen - Arctic sea ice
https://seaice.uni-bremen.de/start

• Danish Meteorological Institute - Arctic sea ice volume and thickness