Methane emerges from warmer areas

As the year draws to a close, it’s time to review where warming has occured most strongly in 2013. Surface temperature anomalies in November 2013 were 0.77°C, the highest global November anomalies on record. In November 2013, high temperature anomalies occurred in the Arctic, well over 9°C north and south of Novaya Zemlya.

Indeed, global warming is hitting the Arctic particularly hard, and some models have underestimated the pace at which this is occuring. Most heat goes into the oceans, which - due to the Gulf Stream - contributes to accelerated warming in the Arctic, where also less monitoring takes place than over land. Stefan Rahmstorf, Co-Chair of Earth System Analysis at the Potsdam Institute for Climate Impact Research, says at RealClimate:

A new study by British and Canadian researchers shows that the global temperature rise of the past 15 years has been greatly underestimated. The reason is the data gaps in the weather station network, especially in the Arctic. If you fill these data gaps using satellite measurements, the warming trend is more than doubled in the widely used HadCRUT4 data.

Where did warming occur most strongly in 2013? The red/orange areas on the image below shows surface temperature anomalies of more than 2°C for the year from December 13, 2012, to December 12, 2012.

As the image shows, temperature anomalies have hit Earth most strongly in the cryosphere, i.e.
- in Antarctica, as discussed at this post;
- on the Qinghai-Tibetan Plateau, as earlier discussed at this post;
- in the Arctic, as discussed below.

Over the past 90 days, the Arctic Ocean has shown surface temperature anomalies of over 5°C and in some spots over 8°C.

Looking at anomalies over longer periods can mask the occurrence of much higher anomalies on individual days. As an example, temperature anomalies of over 20°C were recorded over a large part of the Arctic Ocean on November 17, 2013. 

Baffin Bay, west of Greenland, has until now received little attention. High temperature anomalies over the past year show up on the top image. These high temperatures are the more striking given that a cold sea current runs through Baffin Bay, as shown on the image below. 

Methane has emerged strongly from areas that have warmed most in 2013. In August 2013, high concentrations of methane showed up over Siberia. High methane releases have further occurred in all three parts of the cryosphere mentioned above, i.e. from the heights of Antarctica, as discussed at this post, on the Qinghai-Tibetan Plateau, as earlier discussed at this post, and in the Arctic, as discussed in many posts at the Arctic-news blog.

Huge methane concentrations have featured over Baffin Bay recently. The animation below shows huge methane emissions emerging from Baffin Bay on December 1-2, 2013. The power behind these methane releases is strong enough to make it difficult for thicker ice to form in Baffin Bay. The animation below shows an area marked by a red rectangle where it looks like the water would have been covered with thicker ice, had there not been so much methane bubbling up in the area.

This area with very thin ice in Baffin Bay is further illustrated in the Naval Research Laboratory 30-day Arctic sea ice thickness animation below.

This constitues yet another feedback, i.e. methane bubbling up from the seafloor of the Arctic Ocean with a force strong enough to prevent sea ice from forming in the area. 

Post by Sam Carana.