Friday, May 18, 2012

Striking increase of methane in the Arctic


Click on image to enlarge

Dr. Leonid Yurganov, Senior Research Scientist, JCET, UMBC, and member of AMEG, produced the above images with IASI/METOP satellite data (EUMETSAT).

The images show methane levels for 2008, 1-10 November, and for 2011, 1-10 November.

The images show a striking increase of methane over the shelf areas of the Arctic Ocean.

For reference, the image on the right is added, showing predicted methane hydrates, as published by WWF with surface temperature hotspots added.

Dr. Yurganov points at the threat of large emissions of methane from clathrates (methane hydrates) in the Arctic, and urges others to support his proposals for further satellite methane monitoring.

Current growth of methane is being monitored by the Atmospheric Infrared Sounder (AIRS) facility on NASA's Aqua satellite.

Dr. Yurganov has been using AIRS data for years and points at an image he produced using AIRS data. The image shows that, during the autumn of 2011, the anomaly in the Northern Hemisphere was substantially larger than the anomaly in the Southern Hemisphere.
ftp://asl.umbc.edu/pub/yurganov/methane/AIRS_CH4_2002-2012.pdf

Monthly mean maps of methane are available at Dr. Yurganov's website. The maps have been produced using AIRS data since 2002 up to now, for both the Northern Hemisphere and the Southern Hemisphere. The maps are at:
ftp://asl.umbc.edu/pub/yurganov/methane/MAPS/

Comparisons with other instruments for the Arctic are still few or lacking. Examples are for TANSO, May-November, 2010:
ftp://asl.umbc.edu/pub/yurganov/methane/MAPS/TANSO_2010day&night.jpg

Wednesday, May 2, 2012

Temperature rise projections

The Climate Emergency Institute recently produced the image below. For more background, see the institute's page on the warming that Earth's is already committed to even if people's emissions were suddenly stopped. Also see the institute's warning on Food Security.



Record levels of greenhouse gases in the Arctic

Carbon dioxide levels are at an all time high. The image below, with hourly averages, shows recent measurements that are well over 396 ppm. Formal figure for the week started April 22, 2012, is 396.61 ppm at Mauna Loa, Hawaii.


The image below shows the atmospheric increase of CO2 over 280 ppm in weekly averages of CO2 observed at Mauna Loa. The preindustrial value of 280 ppm is close to the average of CO2 between 1000 and 1800 in an ice core from Law Dome, Antarctica. For comparison with pre-industrial times the Mauna Loa weekly data have been first deseasonalized by subtracting the observed average seasonal cycle, and then subtracting 280 ppm.



The image below shows the results for carbon dioxide global monthly averages for the period 1979-2010. The axis on the left shows the radiative forcing in Watts per square meter, relative to 1750, due to carbon dioxide alone since 1979.



The situation is even worse in the Arctic, where carbon dioxide levels can reach values over 400 ppm, as illustrated by the image below showing carbon dioxide measurements at Barrow, Alaska.



Apart from carbon dioxide, there are further forcers such as methane. The image below shows methane levels at Mauna Loa, Hawaii.


Methane levels are again higher in the Arctic, as illustrated by the image below showing methane levels at Barrow, Alaska, of well over 1900 ppb.
Figures for methane on above image are monthly averages, showing recent levels well over 1900 ppb. The situation looks even more worrying when looking at hourly averages, showing measurements of up to 2500 ppb.


The fact that such high levels occur is alarming. The danger is that radiative forcing will be extremely high in summer in the Arctic, due to high levels of greenhouse gases and other emissions, which will speed up the loss of sea ice, resulting in even further warming that increases the danger that large amounts of methane will be released from hydrates and from free gas in sediments under the water.  This danger is further increased by the many feedbacks, as depicted in the Diagram of Doom.

For a more detailed description of the many feedbacks, see the Diagram of Doom.