Variability in reference evapotranspiration and moisture availability in three agroclimatic zones of Punjab, India

Abstract

A research study was undertaken to estimate reference evapotranspiration (ETO), moisture index (MI) and aridity index (AI) and analyse their trends in different locations/zones of Punjab. Annual and seasonal ETO was observed to be highest in south-west and lowest in north-east zone. North-east zone experienced increasing trend in annual as well as seasonal ETO. Districts within the central zone had large variability within the zone. MI and AI were in the order of north-east zone followed by Central zone and South-west zone indicating better moisture availability conditions in north-east. Mean difference in annual and seasonal MI and AI also indicated statistical similarities within the districts of north-east and south-west zones but different from other zones. Thus, increasing trend of ETO in north-east region and higher ETO range in south-west zone along with severe moisture availability necessitates the need for more careful planning of water resources in the region.

Keywords

• Reference evapotranspiration
• moisture index
• aridity index
• Punjab