Sun Feb 10, 2013, 12:15 PM
hatrack (39,666 posts)
Dramatic Increase In Atmospheric Arctic Methane Levels In January 2013
Below a combination of images produced by Dr. Leonid Yurganov, showing methane levels January 1-10, 2013 (below left), January 11-20, 2013 (below center) and January 21-31, 2013 (below right).
Above image shows dramatic increases of methane levels above the Arctic Ocean in the course of January 2013 in a large area north of Norway.
Why are these high levels of methane showing up there? To further examine this, let's have a look at where the highest sea ice concentrations are. The image below shows sea ice concentrations for January 2013, from the National Snow and Ice data Center (NSIDC).
Overlaying methane measurements with sea ice concentrations shows that the highest levels of methane coincide with areas in the Arctic Ocean without sea ice. This is shown on the animation below, which is a 1.84 MB file that may take some time to fully load.
Where methane levels above the Arctic Ocean are relatively low, there still may be very high levels of methane underneath the sea ice that are still broken down by bacteria, as discussed in the post Further feedbacks of sea ice decline in the Arctic. As that post concludes, much of this methane is likely to enter the atmosphere without getting broken down by bacteria as the sea ice retreats further. Sea ice is declining at exponential pace. The big danger is that a huge rise of temperatures in the Arctic will destabilize huge amounts of methane currently held in the seabed.
The animation further below shows selected NOAA images at different altitudes on January 23, 2013. The lowest altitude is ~111 meters (~364 feet) above sea level. At this altitude, high methane levels (up to ~2000 ppb) show up over the Arctic Ocean, against a global mean of 1793 ppb. Much of the land remains colored grey at this altitude, since no values are registered where the land is higher than this altitude. At all higher altitudes up to ~8 km (~26250 ft) peak values in the Arctic remain visible that are higher than 2000 ppb, up to a staggering 2241 ppb, while global mean methane levels range from 1768 to 1795 ppb.
At even higher altitudes, centrifugal forces move the methane toward locations over the equator. At an altitude of ~16 km (~52000 ft), levels of up to 1880 are recorded over the equator, against mean global levels of ~1700 ppb. All this compares with pre-industrial methane levels of ~715 ppb.
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Dramatic Increase In Atmospheric Arctic Methane Levels In January 2013 (Original post)
|FedUpWithIt All||Feb 2013||#4|
|phantom power||Feb 2013||#9|
Response to hatrack (Original post)
Mon Feb 11, 2013, 08:39 AM
GliderGuider (19,596 posts)
I have it on good authority that this whole methane thing is nothing but unconscionable hysteria! You should be ashamed of yourself, spreading such unfounded, unscientific speculation!!1!1
For newcomers, this was