SM2RAIN-ASCAT (2007-2022): global daily satellite rainfall from ASCAT soil moisture

SM2RAIN-ASCAT is a new global scale rainfall product obtained from ASCAT satellite soil moisture data through the SM2RAIN algorithm (Brocca et al., 2014; 2019). The SM2RAIN-ASCAT rainfall dataset (in mm/day) is provided over a regular grid at 0.1-degree sampling (3600x1801) on a global scale. The product represents the accumulated rainfall between the 00:00 and the 23:59 UTC of the indicated day. The SM2RAIN method was applied to the ASCAT soil moisture product (Wagner et al., 2013) for the period from January 2007 to December 2022 (16 years), for version 2.1.2n. The rainfall dataset is provided in NetCDF format. A total of 16 NetCDF files, one per year, are provided. The quality flag provided with the dataset has been used to mask out low quality data, as well as the areas characterised by complex topographic, frozen soil, and presence of tropical forests. In addition to the daily accumulated rainfall value, also the rainfall noise (mm/day) is provided for every day. Version 2.1.2 should not be used due to an error in the precipitation data. Version 2.1.2n with respect to version 2.1 is calibrated anew and extended to December 2022. A GeoTIFF version of the dataset (v1.5) is available here: https://doi.org/10.5281/zenodo.2615278 A monthly version at 0.25- and 0.5-degree resolution (v1.4) is available here: https://doi.org/10.5281/zenodo.4570191 A sample dataset that can be used for testing SM2RAIN algorithm is available here: https://zenodo.org/record/2580285 Details on the dataset development and its assessment with ground and reanalysis observations are provided as: Brocca, L., Filippucci, P., Hahn, S., Ciabatta, L., Massari, C., Camici, S., Schüller, L., Bojkov, B., Wagner, W. (2019). SM2RAIN-ASCAT (2007-2018): global daily satellite rainfall from ASCAT soil moisture. Earth System Science Data, 11, 1583–1601, doi:10.5194/essd-11-1583-2019. https://doi.org/10.5194/essd-11-1583-2019. Simple Python and Matlab codes for the extraction of SM2RAIN-ASCAT rainfall at one and multiple station(s)\location(s) are available at (note that reader for versions <1.3 are not usable for version >1.3): https://github.com/IRPIhydrology/SM2RAIN_ASCAT_reader The SM2RAIN code in Python is available here: https://github.com/IRPIhydrology/sm2rainThe SM2RAIN code in Matlab is available here: https://github.com/IRPIhydrology/SM2RAIN_MatlabThe SM2RAIN code in R is available here: https://github.com/IRPIhydrology/sm2rainR   Acknowledgements EUMETSAT Global SM2RAIN project (contract n° EUM/CO/17/4600001981/BBo) EUMETSAT "Satellite Application Facility on Support to Operational Hydrology and Water Management (H SAF)" CDOP 3 (EUM/C/85/16/DOC/15).

With respect to previous versions (<1.5.2), the SM data provider have included the data from MetOP-C satellite and have applied a new masking procedure that reduces data availability over frozen areas and coastlines. SM2RAIN was calibrated again in order to take into consideration the new mask and the different life period of MetOP satellites. The data were extended to December 2022. The NetCDF dataset structure is compatible with the latest CF Metadata convention (Working draft) (https://cfconventions.org/)