Drought Monitoring in Northenr China Plain Combing RS and GIS Technology

Drought in sprint is one of the natural disasters that threatens our agriculture development and causes series environment, social and economical consequences. Remote sensing technology becomes possible to rapidly monitor soil moisture in regional scale by combining remote sensing and Geophysical Information Systems technology. In this paper, a thermal inertia map was obtained from MODIS 1B data on April 16, 2004 using thermal inertia model in Northern China Plain covering Latitude from 37degN to 39.5degN and Longitude from 115degE to 117.5degE. A soil moisture map was obtained based on the relationship between thermal inertia and soil moisture. And a distributive map of drought was obtained by dense slicing and some analyses based on the relationship between ranks of drought and soil moisture were performed. The drought map shows that most of the studied area was in a normal condition except some small part of the northern and western eastern was in a slightly drought. The actual drought information obtained from the official Website of Beijing Meteorological Bureau indicates that it was in a normal condition of soil moisture in Northern China Plain in the first ten days of April. The result derived from MODIS data using thermal inertia model is in consistent with the actual situation. It indicates that it is an effective way to monitor regional drought condition by means of deriving soil moisture using MODIS data.