9. Soil Wetness Index (root zone)

DOI: 10.15770/EUM_SAF_H_0008 

The H141/H142 root-zone soil moisture product in the D&V cube is expressed as a liquid Soil Wetness Index (SWI), with units between 0 (residual soil moisture) and 1 (saturation), representing the lower and upper soil moisture limits. 

For the production of H141/H142, liquid SWI observations derived from ERS and ASCAT scatterometer data are bias corrected and assimilated in the H-TESSEL land surface model. After data assimilation, a post-processing step is then required to convert the volumetric soil moisture analysis into the H141/H142 liquid SWI. It is computed using the soil texture, the residual and saturated soil moisture, and the fraction of liquid water content (the fraction of water that is not frozen) on each grid point and each soil layer. Having the units of H141/H142 as a liquid SWI is consistent with the ERS and ASCAT soil moisture observations. The output consists of the liquid SWI in four different soil layers, down to a depth of 2.89 m. 

The Climate Data Record (H141) covers the time period January 1992 – December 2018. The Interim Climate Data Record (H142) covers the time period January 2019 – December 2020. Both products are provided by SAF (http://hsaf.meteoam.it/). 

For a quick overview on these data records as provided in the D&V cube, refer to: 

For further information please refer to: