4DMED precipitation product: 1 km merged precipitation from CPC, IMERG-LR and SM2RAIN-ASCAT for mediterranean basin

The high resolution satellite precipitation product is based on the integration of multiple precipitation and rainfall datasets to generate a high spatial (1 km) and temporal (daily) resolution precipitation product over the Mediterranean area. The following precipitation and rainfall datasets are downscaled and merged together: GPM-Late run, CPC, SM2RAIN-ASCAT. All these products are originally at coarse spatial resolution (>10 km) and have been downscaled to 1 km spatial resolution using CHELSA (1 km) climatology. The three products are then merged with a triple collocation technique. In the areas covered by snow only GPM-Late run and CPC are merged together, again using the triple collocation to obtain the relative weights (third product: ERA5 Land precipitation). The product has been developed in the framework of the 4D-MED Hydrology project. The product is available in the period 2015-2022. Acknowledgements The work is supported by the European Space Agency (ESA) through the 4D-MED Hydrology project (grant no. ESA 4000136272/21/I-EF)