The evidence of abrupt high methane releases in the Arctic Ocean is accumulating. The graph below shows in situ methane measurements taken at the Barrow Observatory, including recent levels as high as close to 2200 parts per billion (ppb).
Satellite data picture a similarly dire situation. Global mean methane levels as high as 1831 ppb were recorded on the morning of July 30, 2014, while peak methane levels as high as 2330 ppb were recorded that morning. More recently, peak methane levels as high as 2522 ppb were recorded (on August 2, 2014).
IPCC/NOAA figures suggest that methane levels were rising by some 5 to 6 ppb annually, reaching 1814 ppb in 2013. While methane levels at lower altitudes have indeed shown little rise, much larger rises have been recorded at higher altitudes, as illustrated by the image below.
These high methane levels recorded at higher altitudes appear to be caused by the huge quantities of methane released from the seafloor of the Arctic Ocean during the period from end 2013 to early 2014. This methane has meanwhile risen to higher altitudes, while also descending to lower latitudes, wreaking havoc on weather patterns around latitude 60° North.
The releases of methane from the seafloor of the Arctic Ocean were caused by water that had warmed up strongly off the east coast of North America from June 2013. It took some months for this warm water to be carried by the Gulf Stream into the Arctic Ocean.
Meanwhile, very high sea surface temperatures are recorded in the Arctic Ocean, as above image shows, while warm water is carried into the Arctic Ocean by the Gulf Stream, as illustrated by the image below.
As said, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.
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