A Review of User Perceptions of Drought Indices and Indicators Used in the Diverse Climates of North America

• Published in: Atmosphere
• Main Authors: Richard R. Heim, Deborah Bathke, Barrie Bonsal, Ernest W. T. Cooper, Trevor Hadwen, Kevin Kodama, Dan McEvoy, Meredith Muth, John W. Nielsen-Gammon, Holly R. Prendeville, Reynaldo Pascual Ramirez, Brad Rippey, David B. Simeral, Richard L. Thoman, Michael S. Timlin, Elizabeth Weight
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2023
• Subjects: user-inspired science; drought impacts; Canada; United States; Mexico; Pacific Islands; Meteorology. Climatology; QC851-999; Pacific; Tundra
• Online Access: https://doi.org/10.3390/atmos14121794; https://doaj.org/article/c6f0934c1c6b4b86b0b490f2b54c9cc3

Drought monitoring and early detection have improved greatly in recent decades through the development and refinement of numerous indices and indicators. However, a lack of guidance, based on user experience, exists as to which drought-monitoring tools are most appropriate in a given location. This review paper summarizes the results of targeted user engagement and the published literature to improve the understanding of drought across North America and to enhance the utility of drought-monitoring tools. Workshops and surveys were used to assess and make general conclusions about the perceived performance of drought indicators, indices and impact information used for monitoring drought in the five main Köppen climate types (Tropical, Temperate, Continental, Polar Tundra, Dry) found across Canada, Mexico, and the United States. In Tropical, humid Temperate, and southerly Continental climates, droughts are perceived to be more short-term (less than 6 months) in duration rather than long-term (more than 6 months). In Polar Tundra climates, Dry climates, Temperate climates with dry warm seasons, and northerly Continental climates, droughts are perceived to be more long-term than short-term. In general, agricultural and hydrological droughts were considered to be the most important drought types. Drought impacts related to agriculture, water supply, ecosystem, and human health were rated to be of greatest importance. Users identified the most effective indices and indicators for monitoring drought across North America to be the U.S. Drought Monitor (USDM) and Standardized Precipitation Index (SPI) (or another measure of precipitation anomaly), followed by the Normalized Difference Vegetation Index (NDVI) (or another satellite-observed vegetation index), temperature anomalies, crop status, soil moisture, streamflow, reservoir storage, water use (demand), and reported drought impacts. Users also noted the importance of indices that measure evapotranspiration, evaporative demand, and snow water content. Drought indices ...