Research on Global Stratospheric Gravity Wave Characteristics by AIRS Observation Data

The atmospheric infrared sounder mounted on the Aqua satellite has the advantage of directly measuring the temperature disturbance caused by gravity waves, and is therefore widely used in stratospheric atmospheric gravity wave research. The global distribution of stratospheric gravity wave activity intensity and occurrence frequency are analyzed using the 79th channel's observation data of the AIRS in January and July between 2012 and 2014. The variation characteristics of gravity wave activity with latitude and longitude are analyzed, and the hot-spot regions of gravity wave activity in the global range and their occurrence frequency are given. The similarities and differences between daytime and nighttime gravity wave activity intensity and occurrence frequency are compared. Results show that the gravity wave intensity varies significantly with latitude. In the low latitude area (0°—30°), the value of the gravity wave intensity in winter hemisphere is low, but is high in summer hemisphere. In the middle and high latitudes, winter hemisphere has strong gravity waves activity but the summer hemisphere gravity wave is weak. In January, there are four prominent hot-spots in the global range, located at 50° north latitude, the continental and Atlantic intersections, and the North American and Atlantic intersections, and at 20° south latitude, the South American and Atlantic intersections, and Africa intersection with the Indian Ocean. In July, the gravity wave activity was prominent in the Patagonia to Antarctic Peninsula region and the Indian Ocean region near 50° south latitude and 75° east longitude. Gravity wave activity intensity is greater at nighttime than daytime, but strong gravity wave activity zone is smaller at night.