A REAL-TIME DROUGHT DECISION-SUPPORT SYSTEM

Since the onset of an extended drought in 1995, the Oklahoma Climatological Survey (OCS) has been the key provider of precipitation-based drought assessments to state officials in Oklahoma. In response to the drought, OCS began producing weekly summaries of precipitation totals and departures for each climate division in the state. Since 1995, through interaction with officials at the Oklahoma Water Resources Board (OWRB), other state agencies, and U.S. Drought Monitor authors, the system has developed into a mature real-time decision-support system.

Each morning before dawn, precipitation totals from the Oklahoma Mesonet are incorporated into a suite of tables and maps that provide assessments on precipitation departures, historical context, and key drought indices. The Mesonet data are merged with historical Cooperative Observer data to determine rankings, records, and analog periods. Assessments for selected time periods ranging from 30 days to 365 days plus standard measures such as calendar year, water year, and current season, are available through the decision-support system.

OCS represents the meteorological / climatological community's input into the state drought assessment processes. OCS collects the data and develops tools to portray information for state decision-makers. OWRB officials, who are charged by statute with monitoring responsibilities, monitors the decision-support system and includes its information in its Water Resources Bulletin, sent to top agency officials, legislative leaders and Governor's staff to keep informed on drought status by region in Oklahoma. New indices, maps, time periods, and links have been added at the request of individual decision-makers. Prototypes were tested by these key user groups as new changes were implemented.

Although this system is built upon real-time quality-controlled information from the Mesonet, the decision-support system has been expanded to use a real-time Cooperative Observer data feed. Similar climate division tables are now being produced by OCS for all of the southern plains states.