The Lincoln Declaration on Drought Indices

Improved drought monitoring and early warning systems are urgently needed to cope with current and potentially changing drought patterns as we move into the future. Drought is a slow-moving natural hazard that can affect virtually all climatic regimes. Generally defined, drought is a deficiency of precipitation relative to what is expected (i.e., “normal”) that, when extended over a season or a longer period of time, results in the inability to meet the demands of human activities and the environment. As countries around the world begin to establish national drought strategies, one critical component should be the development of a comprehensive drought monitoring system that has the ability to provide an early warning of the drought’s onset, determine drought severity and spatial extent, and convey that information to decision-making groups in a timely manner. This information can then be used to either reduce or avoid the impacts of drought.