Drought Monitoring with Remote Sensing Data and Atmospheric Elements

MODIS has the advantages of multi-band, high spatial and temporal resolution, which are propitious to the dynamic monitoring of a large area of arid regions. During late October 2008 and mid-February 2009, more than 10 provinces in east-central and northern China were hit by the severe drought. In this paper, Liaoning Province suffered the serious drought in early 2009 is selected as the study domain. The drought information in MODIS data is extracted through the thermal inertia model, which is used to distinguish the range and the degree of the drought. In order to make a deep analysis of atmospheric structure characteristics and mechanism which led to this drought, wind direction, wind velocity, temperature, humidity and structure characteristics of atmosphere energy during this drought are revealed from two aspects: weather situation, Skew-T diagram. The results show the main reason for this drought is the abnormal atmospheric structure, including the maintenance of dry cold air path caused by the strong and stable northeast cold vortex, the large temperature-dew point difference of the whole troposphere, the little water vapor in source area because of the northwest wind and the stable distribution of atmosphere.