Here
is an analysis of the high methane levels that have been observed
early this year that correspond with a record thin Arctic ice for
winter.
Whilst the situation doesn't look quite the same as the handwritten graph that I drew last weekend the situation remains dire.
On
a very superficial reading of this this seems to be the most
important point
“From
January 1 to March 20, 2015, methane levels reached levels as high as
2619 ppb (on January 12, 2015), while peak daily levels averaged 2373
parts per billion (ppb). At the start of the year, global mean
methane levels typically reach their lowest point, while highest mean
levels are typically reached in September”
There
is absolutely no doubt that the process of methane emissions is
accelerating.
The
worry is that in the case of a blue water event this summer there
could conceivably be a warming of the ocean leading to the methane
burb talked of by Natalia Shakhova.
Methane
Levels Early 2015
27
March, 2015
Below
is a comparison of highest mean methane readings between three years,
i.e. 2013, 2014 and 2015, at selected altitudes on March 10. The
comparison indicates that the increase of methane in the atmosphere
is accelerating, especially at higher altitudes.
The
table below shows the altitude equivalents in mb (millibar) and feet.
56925 feet | 44689 feet | 36850 feet | 30569 feet | 25543 feet | 19819 feet | 14383 feet | 8367 feet | 1916 feet |
74 mb | 147 mb | 218 mb | 293 mb | 367 mb | 469 mb | 586 mb | 742 mb | 945 mb |
This
rise in global mean methane levels appears to go hand in hand with
much higher peak readings, especially at higher altitudes.
From
January 1 to March 20, 2015, methane levels reached levels as high as
2619 ppb (on January 12, 2015), while peak daily levels averaged 2373
parts per billion (ppb). At the start of the year, global mean
methane levels typically reach their lowest point, while highest mean
levels are typically reached in September. Highest daily global mean
methane levels for the period from January 1, 2015, to March 20,
2015, ranged from 1807 ppb (January 6, 2015) to 1827 ppb (March 5,
2015).
Further
study of the locations with high methane levels indicates that much
of the additional methane appears to originate from releases at
higher latitudes of the Northern Hemisphere, in particular from the
Arctic Ocean, from where it is over time descending toward the
equator (methane will typically move closer to the equator over time
as it rises in altitude, as discussed in this earlier post).
The
largest source of additional methane appears to be emissions from the
seabed of the Arctic Ocean. Annual emissions from hydrates were
estimated to amount to 99 Tg annually in a 2014 post (image below).
The
image below, based on data from the IPCC and the World Metereological
Organization (WMO), with an added observation from a NOAA MetOp
satellite image, illustrates the recent rise of methane levels and
the threat that methane levels will continue to rise rapidly.
What
causes these methane eruptions?
Methane
eruptions from the seafloor of the Arctic Ocean appear to be
primarily caused by rising ocean heat that is carried by the Gulf
Stream into the Arctic Ocean. The image below shows sea surface
temperatures of 20.9°C (69.62°F, green circle left) recorded off
the coast of North America on March 14, 2015, an anomaly of 12.3°C
(36.54°F).
[ click on image to enlarge ] |
Furthermore,
both methane eruptions from the Arctic Ocean seafloor and demise of
the Arctic sea ice and snow cover are feedbacks that can interact and
amplify each other in non-linear ways, resulting in rapid and intense
temperature rises, as illustrated by the image below.
Diagram of Doom - for more background, see Feedbacks |
How
high could temperatures rise?
Worryingly,
a non-linear trend is also contained in the temperature data that
NASA has gathered over the years, as described in an earlier post. A
polynomial trendline points at global temperature anomalies of over
4°C by 2060. Even worse, a polynomial trend for the Arctic shows
temperature anomalies of over 4°C by 2020, 6°C by 2030 and 15°C by
2050, threatening to cause major feedbacks to kick in, including
albedo changes and methane releases that will trigger runaway global
warming that looks set to eventually catch up with accelerated
warming in the Arctic and result in global temperature anomalies of
16°C by 2052
[ click on image to enlarge ] |
Action
The
situation is dire and calls for comprehensive and effective action,
as discussed at the Climate
Plan blog.
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