A peak methane level of 3026 ppb was recorded by the MetOp-B satellite at 469 mb on December 11, 2021 am.
This follows a peak methane level of 3644 ppb recorded by the MetOp-B satellite at 367 mb on November 21, 2021, pm.
Also, the image was recorded later than the image at the top with the 3026 ppb peak, indicating that even more methane may be on the way. This appears to be confirmed by the Copernicus forecast for December 12, 2021, 03 UTC, as illustrated by the image below, which shows methane at 500 hPa (equivalent to 500 mb).
What causes these terrifying methane levels?
As the combination image below shows, the sea surface temperature north of Svalbard was as high as 4.3°C (or 39.74°F, green circle in the left panel) on December 12, 2021, i.e. as much as 5°C (or 9°F, green circle in the right panel) higher than 1981-2011.
[ click on images to enlarge ] |
At times, this can lead to very strong winds that push huge amounts of heat from the North Atlantic into the Arctic Ocean.
Huge amounts of heat can thus move into the Arctic Ocean, driven by ocean currents and temperature differences.
The danger is that warmer water will cause methane to erupt from the seafloor of the Arctic Ocean, as an earlier post warned.
[ The buffer is gone, from earlier post ] |
Sea ice used to act as a buffer, by consuming energy in the process of melting, thus avoiding that this energy could raise the temperature of the water of the Arctic Ocean. As above image indicates, the buffer has now virtually disappeared.
Heat that was previously melting the ice or that was getting transferred to the atmosphere is now instead heating up the water. Some 75% of ESAS (East Siberian Arctic Shelf) is shallower than 50 m. Being shallow, these waters can easily warm up all the way down to the sea floor, where heat can penetrate cracks and conduits, destabilizing methane hydrates and sediments that were until now sealing off methane held in chambers in the form of free gas in these sediments.
Sealed off from the atmosphere by sea ice, greater mixing of heat in the water will occur down to the seafloor of the Arctic Ocean.
[ From the post September 2015 Sea Surface Warmest On Record ] |
Also, as land around the Arctic Ocean freezes over, less fresh water will flow from rivers into the Arctic Ocean. As a result, the salt content of the Arctic Ocean increases, all the way down to the seafloor of the Arctic Ocean, making it easier for ice in cracks and passages in sediments at the seafloor to melt, allowing methane contained in the sediment to escape. Meanwhile, salty and warm water (i.e. warmer than water that is present in the Arctic Ocean) keeps getting carried along the track of the Gulf Stream into the Arctic Ocean.
The threat
[ The Buffer has gone, feedback #14 on the Feedbacks page ] |
A study published November 2021 in Science Advances finds a continuous rise of the tropopause in the Northern Hemisphere over 1980–2020, resulting primarily from tropospheric warming.
As illustrated by the image below, methane on December 26 am, 2021, reached a global mean of 1939 ppb between 293 mb and 280 mb, while the highest peak level (2554 ppb) was reached higher in the atmosphere, at 218 mb.
[ click on images to enlarge ] |
Now add an additional 5 Gt of methane from an abrupt eruption of the seafloor, which is only 10% of the 50Gt that Natalia Shakhova et al. warned about long ago, while 50 Gt is in turn only a small fraction of all the methane contained in sediments in the Arctic. Such an eruption of seafloor methane would raise the global mean methane concentration by almost 2000 ppb which, at a 1-year GWP of 200, would translate into 400 ppm CO₂.
So, that would abruptly cause the joint CO₂e of methane and CO₂ to cross the 1200 ppm clouds tipping point, triggering a further 8°C global temperature rise, due to the clouds feedback.
Conclusion
The situation is dire and calls for the most comprehensive and effective action, as described at the Climate Plan.
Links
https://arctic-news.blogspot.com/p/climateplan.html