Study On Remote Sensing Retrieving Of Soil Moisture Using MODIS Data

Monitoring changes in land surface and marine ecosystems is an important field of remote sensing technology applications. Soil moisture is a key variable in many areas of hydrology, climate,ecology and so on,a wide range of soil moisture monitoring has always been a hot topic of research. The traditional methods are time-consuming, it is difficult to meet the needs of scientific research and related departments to monitor a large area and comprehensive analysis. The MODIS data with high spectral resolution as well as free access,and it has many other advantages, so based on MODIS data to monitor soil moisture has some practical value.In this paper, Dongying City, for example, combining with data from four meteorological stations, using MODIS data build the model of soil moisture sensing. Then inversion different time series of soil moisture conditions in Dongying City. The main contents include:1.Summarize the principles and methods of drought monitoring, introduces the research status of various types of research methods; 2. Analyzes the technical indicators and the band uses MODIS data; and systematically studied the monitoring data processing and data retrieval precision arithmetic; 3.Study established a model of thermal inertia and temperature conditions of vegetation index model using MODIS data to monitor Dongying City soil moisture; 4 Using vegetation index conditions of temperature model inverter three different time series of vegetation index values in Dongying City,within the analyzed trends of soil moisture during these time series.Through this study, the following conclusions: 1.due to the high spectral resolution and continuity of the MODIS data, it is the best data sources to monitoring in a wide range.2.thermal inertia model mainly consider the spectral characteristics of the soil surface, and temperature changes,do not apply to high vegetation coverage area; 3.vegetation index modelinversion of soil moisture, based on the soil water content impact on vegetation growth status will reflected in the vegetation spectral characteristics,so the principle could only applies to certain areas of vegetation cover; 4. herein choose 16 days, the time sequence of the quarter and year, to inverter soil moisture,analysis the trends in Dongying City, found that in a year,changes in the value of the VTCI obviously,in recent years did not appear drought or floods and other extreme disasters in Dongying City.