Monitoring of Arctic surface sudden warming events in late December 2015 with satellite remote sensing data

Abstract

The explosively sudden warming of synoptic scale at the Arctic surface is often caused by meridional transport of lower latitude warm air or the ocean warm currents into the Arctic. The explosively sudden warming event that the Arctic surface temperature reached above 0°C on 29th December 2015 caused global concern. In the present paper, a variety of remote sensing data obtained by the AIRS (Atmospheric Infrared Sounder) flying on board NASA’s Aqua satellite were applied to monitor the abrupt changes in the atmospheric temperature, water vapor and ozone over the Flam Strait. AIRS measurements showed that the water vapor and temperature increased significantly beginning on December 27th, reached a peak on the 29th, then began to fall and oscillate, remaining above the December average value until January 2nd. At the same time, the atmospheric ozone showed the opposite change, having significantly reduced beginning on the 27th, and reached the minimum value on the 29th, after which it began to rebound and oscillate, then returned to near the December average value until January 2nd. The water vapor mainly changed from the surface to the 100 hPa height. On December 29th, the maximum increase of water vapor reached six times that of the December average at the 400 hPa height, the temperature changes mainly occurring from the surface to the 250 hPa height. The surface temperature reached to above 0°C on the 29th. The total amount of ozone changes became faster and greater. Compared to December 26th, the total amount of ozone reduced by 102 DU, thus reaching more than 1/3 of the December average. The ozone vertical profile mainly changed at the 400–5 hPa height. Compared to the 27th, the reduction of the ozone vertical profile accounted for 80%–90% of the total amount at this height on December 29th. Using NCEP reanalysis data, further combined with HYSPLIT air mass backward trajectory tracking, the analysis showed that the functionary mechanism which caused the surface explosively sudden warming was that the North Atlantic low-pressure storms rapidly transported large amounts of warm and moist air at low latitudes to the Arctic, which led to a dramatic increase in the low layer temperature and water vapor content. Additionally, the atmosphere was transported from low latitudes to higher latitudes, thereby harmonizing with the vertical motion of the atmosphere from the low level to the upper level. This led to the dramatic changes in ozone distribution from the upper troposphere to the stratosphere, in turn resulting in dramatic changes in the total ozone and vertical profiles. A typical example of satellite remote sensing monitoring showed that it was the power transmission of the synoptic scale which caused the rapid and dramatic changes of heat, water vapor and ozone in the Arctic.