Spatiotemporal geostatistical analysis of precipitation combining ground and satellite observations

Abstract

Precipitation data are useful for the management of water resources as well as flood and drought events. However, precipitation monitoring is sparse and often unreliable in regions with complicated geomorphology. Subsequently, the spatial variability of the precipitation distribution is frequently represented incorrectly. Satellite precipitation data provide an attractive supplement to ground observations. However, satellite data involve errors due to the complexity of the retrieval algorithms and/or the presence of obstacles that affect the infrared observation capability. This work presents a methodology that combines satellite and ground observations leading to improved spatiotemporal mapping and analysis of precipitation. The applied methodology is based on space–time regression kriging. The case study refers to the island of Crete, Greece, for the time period of 2010–2018. Precipitation data from 53 stations are used in combination with satellite images for the reference period. This work introduces an improved spatiotemporal approach for precipitation mapping. HIGHLIGHTS Space-time precipitation trend model incorporating satellite measurements and elevation.; Application of 3D distance metric for spatiotemporal prediction.; Application of the non-separable Spartan space–time variogram in precipitation data.; Space–time residual kriging in geostatistical analysis of non-stationary data.;

Keywords

• crete
• precipitation
• satellite data
• space–time kriging
• spartan variogram
• sum-metric variogram