Theme-6-1-Agricultural meteorologic and hydrologic drought relations.

Abstract

Agricultural and hydrologic droughts affect a large segment of the population. Both have their roots,in meteorologic drought. Meteorologic drought occurs when precipitation over a large area is much below average for an extended period of time. Hydrologic drought (caused by low precipitation, substantial soil moisture deficits, ad high temperatures) occurs when streamflow in a given basin is much below average for several months and available water withdrawals are inadequate. Meteorologic and hydrologic factors can combine to substantially reduce crop yields, leading to an agricultural drought. Interrelationships among these droughts are investigated using long term historical data on precipitation, temperature, streamflow, and crop yields.