How to compute the land cover evapotranspiration at regional scale? A spatial approach of Emilia-Romagna region
Abstract
The Earth is rapidly changing in both its climate and its land distribution. The numerous methods from the literature show various possibilities to assess the crop evapotranspiration and evaporation rate, both with direct measurements and empirical formulas. The present paper brings forward a methodology that demonstrates how to compute the potential land cover evapotranspiration (ETc) at regional scale using climate data from 13 meteorological stations, empirical equations, Corine Land Cover data, and the Geographical Information System (GIS). Based on Thornthwaite method and evapotranspiration coefficients, the study assesses the ETc of Emilia-Romagna region in four stages. Moreover, the Budyko approach was applied to calculate the actual evapotraspiration (AET0) and actual land cover evapotranspiration (AETc) to identify the critical areas of water deficit. Po Plain represents an area with high evapotranspiration rate, due to temperatures and cultivation patterns. A value of 778.87 mm/year at Ferrara station was calculated for the potential evapotranspiration (ET0), while the ETc ranging to 800-1000 mm/year in the central and northeastern part of the region. The AETc reached the maximum values of724 mm in the southcentral part of the Emilia-Romagna