Monitoring Watershed Drought Conditions through the Landsat Imagery Interpretation

作者：Li Ruopu; Zhao Leiming; Haigh Tonya; Tang Zhenghong^*

来源：Disaster Advances, 2010, 3(4): 40-46.

• Landsat
• watershed
• unsupervised classification
• a-Modified Normalized Difference Water Index (MNDWI(a))

Lake area is one of the most important hydrologic indicators of drought in the Apalachicola-Chattahoochee-Flint (ACF) watershed. However, conducting a field survey of lake areas over a large region is usually infeasible and costly. The Landsat satellite imagery with moderate spatial, spectral and temporal resolutions has the capacity to quantify lake areas. This paper demonstrated two methods - unsupervised classification and a-Modified Normalized Difference Water Index (MNDWI(a)) - to estimate the lake water area in ACF watershed. The estimated lake areas were used to correlate other hydrologic factors like precipitation. The results showed better performance of unsupervised classification than MNDWL No correlation between accumulated precipitation and lake area fluctuation was detected, indicating more complex hydrologic mechanism existing in the large river basin.

• 出版日期2010-10