LINCOLN, Neb. -- In the "Lincoln Declaration on Drought Indices," 54 experts from all regions of the world agreed this month on the use of a universal meteorological drought index for more effective drought monitoring and climate risk management.

A World Meteorological Organization official presented the declaration Dec. 15 at the climate change summit in Copenhagen, because scientists predict that more drought will be one of the results of climate change.

The experts considered the three main types of drought: meteorological, agricultural and hydrological. Standard ways of measuring drought will provide the basis for global communication about drought and will contribute to early warning systems so policymakers and the international aid community can deliver more timely relief.

Experts participating in the Inter-Regional Workshop on Indices and Early Warning Systems for Drought, held in Lincoln Dec. 8-11, made a significant step in agreeing that all National Meteorological and Hydrological Services around the world should use the Standardized Precipitation Index to characterize meteorological droughts.

"Given the complexity in defining drought historically, the selection of a primary index or measure of meteorological drought is an important step forward," said Donald A. Wilhite, director of the University of Nebraska-Lincoln's School of Natural Resources. "This is a step toward developing early warning systems to improve drought preparedness world-wide."

The workshop was jointly sponsored by the School of Natural Resources and the National Drought Mitigation Center at UNL, the World Meteorological Organization, the U.S. National Oceanic and Atmospheric Administration, the U.S. Department of Agriculture, and the United Nations Convention to Combat Desertification.

The SPI is an index that calculates the probability of precipitation for any selected time scale, based on the long-term precipitation record. SPI values range from more than 2 (extremely wet) to less than -2 (extremely dry), with .99 to -.99 considered the near-normal range. Maps normally depict SPI values as colors, with reds and yellows meaning dry and greens and blues meaning wet.

Various agencies and organizations in the United States regularly compute the SPI, including the National Drought Mitigation Center. The World Meterological Organization will develop a user manual on the SPI to help countries that have not yet implemented it.

Workshop participants suggested that the WMO establish working groups to recommend universal indices for agricultural and hydrological droughts within a year. The same level of drought severity can cause different impacts in different regions due to varying vulnerabilities, so workshop participants also recommended that a simple, systematic analysis of drought impacts in different sectors should be initiated in all affected countries.

SOURCE: University of Nebraska.