Quality Assurance Procedures for Reclamation's AgriMET Weather Station Network

Competition for limited water resources in the western United States continues to increase. To this end, the U.S. Bureau of Reclamation (Reclamation) and Bonneville Power Administration (BPA) partnered to create a network of automated agricultural weather stations - called AgriMet - in the Pacific Northwest. These stations collect and telemeter the meteorological parameters required to model crop evapotranspiration (ET). The information is used by irrigation districts, farmers, resource conservation agencies, and agricultural consultants for irrigation scheduling and related purposes. The network consists of over 70 weather stations in the Pacific Northwest that telemeter weather data each hour via the Geostationary Operational Environmental satellite (GOES). Each station measures air temperature, relative humidity, solar radiation, wind speed, wind direction, and precipitation. Other stations have additional sensors, such as soil temperature, crop canopy temperature, leaf wetness, and diffuse solar radiation. Accuracy of the weather data is critical to successful crop water use modeling and other applications. Quality assurance for the AgriMet program consists of five interdependent components: laboratory sensor calibration, an annual maintenance and calibration visit to each weather station, automated data quality control procedures, manual data quality control procedures, and an annual review of weather and associated evapotranspiration parameters.