Application of FY-2 precipitation data in meteorological drought monitoring of the Weihe river basin

摘要

The remote sensing data have become the irreplaceable source of data for the regions with little or without rainfall data, but these data also require scientific analysis, correction and application. This paper uses FY-2 rainfall data and the case studies of the droughts occurred in the Weihe River Basin from 2006 to 2009 to monitor the spatial and temporal evolution of climatic droughts. The monitoring results indicate that: (1) Except for 2008 which was a dry year, the other years in the Weihe River Basin had normal dry/wet conditions; (2) From October 2008 to January 2009, the rainfall was significantly reduced across the Weihe River Basin, and the continual rainfall was even less than 1 mm for December and January with a precipitation anomaly percentage lower than -80%, a sign of severe climatic drought. But the rainfall has improved since February 2009, when the precipitation reached 17.8 mm and Pa exceeded 100%, which helped to relieve the stress from drought resistance. A heavy precipitation continued for four months from June to September 2008, with the Pa exceeding 50%; (3) Due to the better temporal and spatial continuity than the ground-based meteorological observation, FY-2 precipitation data have good application prospects in the meteorological drought monitoring at a national or regional macro-scale.