Drought Terms and Definitions

This list outlines terms commonly used for drought planning and monitoring purposes.
  • Drought Indices: Assimilate data on rainfall, snowpack, streamflow, and other water supply measurements into a comprehensible picture of drought development and severity (NDMC website, “What Is Drought: Drought Indices,” Michael Hayes). Some examples of common drought indices are: Palmer Drought Severity Index, Crop Moisture Index, Surface Water Supply Index, and the Standardized Precipitation Index.
  • Drought Management Planning: Includes drought mitigation and drought response planning. The main objective of drought management planning is to preserve essential public services and minimize the adverse effects of a water supply emergency on public health and safety, economic activity, environmental resources, and individual lifestyles.
  • Drought Mitigation: Refers to actions taken in advance of a drought that reduce potential drought-related impacts when the event occurs. This includes measures taken in advance of a disaster that are aimed at decreasing or eliminating drought impacts on society and the environment.
  • Drought Stages: Describe the severity levels of drought and are generally differentiated by pre-defined trigger points or thresholds.
  • Drought Types
    • Meteorological drought – a period of below-average precipitation.
    • Agricultural drought – a period of inadequate water supply to meet the needs of the state’s crops and other agricultural operations such as livestock.
    • Hydrological drought – deficiencies in surface and subsurface water supplies. Generally measured as streamflow, snowpack, and as lake, reservoir, and groundwater levels.
    • Socioeconomic drought – occurs when drought impacts health, well-being, and quality of life, or when a drought starts to have an adverse economic impact on a region.

          Dictionary - Terms and Definitions

  • Impact: Measured or observed affect of drought that could include social, economic, and environmental sectors.
  • Response Action: Actions that will be carried out during a drought as various drought trigger points are reached. Response strategies can include anything from short-term emergency aid to government assistance programs and media relations.
  • Response Planning: Addresses the conditions under which a drought induced water supply shortage occurs and specifies the actions that should be taken in response.
  • Risk: A combination of hazard, vulnerability, and exposure. Risk assesses the impact a hazard would have on people, services, facilities, and structures in a community and refers to the likelihood of a hazard event resulting in an adverse condition that causes injury or damage. Vulnerability As defined by FEMA’s risk assessment guidance (FEMA 386-2),
  • Vulnerability: Being open to damage or attack. Vulnerability is also defined as the likelihood that an area or sector will be negatively affected by environmental hazards (Bolin and Stanford, 1998).

 Additional Information