Technologies Spatiales pour la Surveillance et la Gestion de la Sécheresse
Merci à Mussa Kachunga Stanis d'avoir traduit cet article volontairement.
Standardized Soil Moisture Index (SSI)
“SSI is based on the concept of percent of normal precipitation and Palmer Z-index, as well as the statistical construct of SPI. SSI essentially utilizes the z-score to explain how many standard deviations the soil moisture deviates from the historical mean soil moisture, and thus identifies droughts as statistical outliers in the time series
SSI =(xSMAP - µNLDAS )÷σNLDAS
where xSMAP is the soil moisture content from SMAP Level 3 data for a single day, µNLDAS is the mean value of soil moisture content for the corresponding day from NLDAS, and σNLDAS is the standard deviation” (Xu et al., 2018)
Sources
Xu, Yaping, Lei Wang, Kenton W. Ross, Cuiling Liu, and Kimberly Berry. 2018. “Standardized Soil Moisture Index for Drought Monitoring Based on Soil Moisture Active Passive Observations and 36 Years of North American Land Data Assimilation System Data: A Case Study in the Southeast United States.” Remote Sensing 10, no. 2 (February): 301. https://doi.org/10.3390/rs10020301.