Water availability, evaporative demand and climate change. Water availability is the balance between supply (i.e., rainfall) and evaporative demand. Rainfall is well studied but evaporative demand is not. The scientifically useful measure of evaporative demand is the rate of evaporation of water from a metal pan - called pan evaporation. Worldwide measurements show decreasing pan evaporation rate over the last 30-50 years. This project will for the first time make a detailed study of that phenom ....Water availability, evaporative demand and climate change. Water availability is the balance between supply (i.e., rainfall) and evaporative demand. Rainfall is well studied but evaporative demand is not. The scientifically useful measure of evaporative demand is the rate of evaporation of water from a metal pan - called pan evaporation. Worldwide measurements show decreasing pan evaporation rate over the last 30-50 years. This project will for the first time make a detailed study of that phenomenon using a new purpose-built evaporation pan. This will result in better information and policy advice about changes in water availability with climate change.Read moreRead less