Originally published on

by at Arctic News

NOAA’s globally averaged marine surface monthly mean methane reading for November 2021 of 1909.3 parts per billion (ppb) is 17.6 ppb higher than the reading for November 2020. By comparison, NOAA’s annual global mean methane increase of 15.57 ppb for 2020 was at the time the highest on record.

Keep in mind that this 1909.3 ppb reading is for November 2021; it now is March 2022. Furthermore, NOAA’s data are for marine surface measurements; more methane tends to accumulate at higher altitudes.

The image below shows that the MetOp-B satellite recorded a mean methane level of 1936 ppb at 321 mb on March 7, 2022 pm.

Carbon dioxide levels are currently very high over the Arctic, as illustrated by the image below that shows carbon dioxide levels approaching 430 parts per million (ppm) recently at Barrow, Alaska. 

The danger is that high greenhouse gas levels could combine to push the carbon dioxide equivalent (CO₂e) level over the 1200 ppm clouds tipping point in one spot, causing low-altitude clouds in various neighboring areas to break up, propagating break-up of clouds in further areas, as discussed at the clouds feedback page.

The MetOp-B satellite recorded a mean methane level of 1958 ppb on October 25, 2021 am at 295 mb. When using a 1-year GWP of 200, this translates into 391.6 ppm CO₂e. Together with a global mean CO₂ level of 420 ppm, that’s 811.6 ppm CO₂e, i.e. only 388.4 ppm CO₂e away from the 1200 ppm CO₂e clouds tipping point. 

An additional 5 Gt of methane from an abrupt eruption of the seafloor could raise the global mean methane concentration by almost 2000 ppb which, at a 1-year GWP of 200, would translate into an extra 400 ppm CO₂e, thus pushing the joint impact of just two greenhouse gases (carbon dioxide and methane) above the 1200 ppm CO₂e clouds tipping point. 

The situation is dire and calls for the most comprehensive and effective action, as described at the Climate Plan.

Links

• NOAA – globally averaged marine surface monthly mean methane data
https://gml.noaa.gov/webdata/ccgg/trends/ch4/ch4_mm_gl.txt

• NOAA – globally averaged marine surface annual mean methane growth rates
https://gml.noaa.gov/webdata/ccgg/trends/ch4/ch4_gr_gl.txt

• NOAA – Infrared Atmospheric Sounding Interferometer (IASI) Sounding Products (MetOp-B)
https://www.ospo.noaa.gov/Products/atmosphere/soundings/iasi

• NOAA – Trends in Atmospheric Carbon Dioxide

https://gml.noaa.gov/ccgg/trends/gl_trend.html

• NOAA – Carbon Cycle Gases, Barrow Atmospheric Baseline Observatory, United States
https://gml.noaa.gov/dv/iadv/graph.php?code=BRW

• NOAA – Trends in Atmospheric Carbon Dioxide, Mauna Loa, Hawaii
https://gml.noaa.gov/ccgg/trends/graph.html

• Clouds feedback page
https://arctic-news.blogspot.com/p/clouds-feedback.html

• Human Extinction by 2022?
https://arctic-news.blogspot.com/2021/11/human-extinction-by-2022.html

• Terrifying Arctic methane levels
https://arctic-news.blogspot.com/2021/12/terrifying-arctic-methane-levels.html

• Terrifying Arctic methane levels continue
https://arctic-news.blogspot.com/2022/01/terrifying-arctic-greenhouse-gas-levels-continue.html

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html