In 2020 and 2021, the global network of the World Meteorological Organization (WMO) detected the largest within-year increases (15 and 18 ppb, respectively) of atmospheric methane (CH₄) since systematic measurements began in the early 1980s.
|[ IPCC/WMO data through 2021 ]|
The WMO adds that analyses of measurements of the abundances
of atmospheric CH₄ and its stable carbon
isotope ratio ¹³C/¹²C (reported as δ¹³C(CH₄)) indicate that the increase in CH₄ since 2007 is associated with biogenic
Methane's rise has been accelerating since 2007, which makes this a scary suggestion, as increasing decomposition of plant material as a result of climate change is a self-reinforcing feedback loop that is hard to stop.
Interestingly, a different explanation is pointed at in the 2019 analysis is shale gas a major driver of recent increase in global atmospheric methane?.
This could still mean that plant material is now getting decomposed at higher rates, but an even larger danger is that methane emissions started to increase more strongly from the early 2000s due in part to more methane eruptions from the seafloor of the Arctic Ocean. In other words, while hydroxyl kept increasing, seafloor methane emissions kept increasing even faster, to the extent that methane emissions increasingly started to overwhelm this growth in hydroxyl, resulting in a stronger rise in overall methane abundance in the atmosphere.
Sadly, there are few measurements available for methane that could erupt from the seafloor of the Arctic Ocean. Moreover, WMO and NOAA data that are used to calculate global means are typically taken at marine surface level, which may be appropriate for carbon dioxide that is present more strongly at sea surface level, but methane is much lighter and will rise quickly and accumulate at higher altitude, as indicated by the satellite images further below. Moreover, the lack of measurements of methane over the Arctic Ocean and at higher altitudes makes it hard to determine from where the methane originated. Much methane could originate from the seafloor of the Arctic Ocean and rise to the Tropopause, while moving from there closer to the Equator, all largely without getting reported.
What's happening in 2022?
So, what's happening in 2022? Well, it appears that the rise in methane keeps accelerating, as illustrated by the image below showing daily average methane measurements at Mauna Loa, Hawaii, since 2001.
The image below shows methane in situ measurements at Barrow, Alaska, indicating that methane is present in even higher abundance over the Arctic and that levels are rising fast over the Arctic.
The above 1981 ppb mean methane level translates into 396.2 ppm CO₂e at a 1-year GWP of 200. Destabilization of sediments at the seafloor of the Arctic Ocean could cause a large abrupt burst of methane to enter the atmosphere over the Arctic Ocean. A doubling of the mean methane level could push up the mean methane level to twice as much, to 792.4 ppm CO₂e, which is only 407.6 ppm CO₂ away from the 1200 ppm CO₂e clouds tipping point that on its own could push up the temperature by some 8°C globally. This gap of 407.6 ppm CO₂ could be more than covered by the current carbon dioxide level. The September 2022 CO₂ level at Mauna Loa was higher than that, i.e. 415.96 ppm. Since the CO₂ level at Mauna Loa in September typically is at its lowest point for the year, this implies that a large abrupt burst of methane could cause the the clouds tipping point to be instantly crossed due to methane and CO₂ alone.
|[ from earlier post ]|
The MetOp satellite recorded a peak methane level of 3644 ppb and a mean level of 1944 ppb at 367 mb on November 21, 2021, pm, as discussed in an earlier post. This 3644 ppb translates into 728.8 ppm CO₂e, again at a 1-year GWP of 200. This is 471.2 ppm CO₂e away from the clouds tipping point and that 471.2 ppm CO₂e could be covered by the carbon dioxide, nitrous oxide and CFCs currently in the atmosphere.
How high could the temperature rise be by 2026?
There are a number of scenarios that could cause the clouds tipping point to be crossed soon, e.g. if the rise in methane kept following a trend as depicted in the image below, showing WMO 2015-2021 global annual surface mean methane abundance, with a trend added.
|[ click on images to enlarge ]|
|[ from earlier post ]|
|[ from Track Buckling Research ]|
|[ see the Extinction page ]|
With a temperature rise of more than 10°C by 2026, the clouds tipping point will also be crossed, which would result in a total rise of more than 18°C by 2026. Keep in mind that humans are likely to go extinct with a rise of 3°C, as illustrated by the image below, from an analysis discussed in an earlier post.
• WMO - More bad news for the planet: greenhouse gas levels hit new highs
• WMO - Greenhouse Gas Bulletin
• NOAA - Global Monitoring Laboratory
• Copernicus methane at 500 hPa, forecast for October 18, 2022, 03 UTC
• What the IPCC impacts report is hiding
• Climate Endgame: Exploring catastrophic climate change scenarios - by Luke Kemp et al.
Also discussed at:
• The Clouds Feedback and the Clouds Tipping Point
• Arctic Ocean invaded by hot, salty water
• NOAA - MetOp satellite
• The Importance of Methane in Climate Change
• Overshoot or Omnicide?
• Human Extinction by 2022?
• Cataclysmic Alignment
• NOAA National Centers for Environmental Information, State of the Climate: Monthly Global Climate Report for September 2022, retrieved October 16, 2022
• NOAA Climate Prediction Center - ENSO: Recent Evolution,
Current Status and Predictions
• Crossing 3C
• Invisible ship tracks show large cloud sensitivity to aerosol - by Peter Manhausen et al.