The USDA UV-B Monitoring and Research Program is a program of the US Department of Agriculture's Cooperative State Research, Education and Extension Service (CSREES). The program was initiated in 1992, through a grant to Colorado State University, to provide information on the geographical distribution and temporal trends of UVB (ultraviolet -B) radiation in the United States. This information is critical to the assessment of the potential impacts of increasing ultraviolet radiation levels on agricultural crops and forests. Specifically the monitoring program:

• Provides information to the agricultural community and others about
  the climatological and geographical distribution of UVB irradiance;

• Furnishes the basic information necessary to support evaluations of
  the potential damage effects of UVB to agricultural crops and forests;

• Supplies ground truth for satellite measurements and basic information
  for radiation transfer model calculations;

• Establishes long-term records of UVB irradiance necessary to assess trends;

In a broader sense, the monitoring program supports research that increases our understanding of the factors controlling surface UVB irradiance and provides the data necessary for assessing the impact of UVB radiation on human health, ecosystems and materials.

The program consists of both a research and climatological network. The research network provides state-of-the-art, high resolution spectroradiometers to selected sites (6 altogether) where key collaborative research allows cross-disciplinary use of the data. The climatological network requires less sophisticated instrumentation and will eventually total between 30-40 monitoring stations.

The Climatological Network

The climatology network of the USDA-CSREES monitoring program is designed to provide an adequate density of measurement sites to establish the spatial and temporal characteristics of UVB irradiance. The network follows a grid-based design which divides the country into 26 regions of approximately equal-area. Sites are located primarily in rural areas, with particular consideration given to agricultural and forested regions. Initial site locations were also chosen to evaluate their suitability as research sites which will use high resolution spectroradiometers.

Thirty to forty sites are envisioned across this design when the network is fully established. When the network is completed, all sites will be instrumented with both broadband meters and shadowbanded multi-filter instruments and all sites will follow a standardized measurement protocol. For more information about the climatological network click on the Stations/Data menu item.

Research Activities

Research activities are focused towards challenging our current understanding of factors which control UV irradiance and towards improving the quality of UV monitoring instrumentation and data. One aspect of these activities is the establishment of a small research network of high resolution scanning spectroradiometers in areas of the country which represent different atmospheric conditions of major importance to UVB attenuation.

Sites included in the research network will additionally provide key opportunities for collaborative research and provide calibration benchmarks for the USDA climatological network as well as other US Global Change agencies involved in UV research. For more information about the research network click on the Research Network menu item under the Research menu at the right.

Collocation of network sites with other major North American radiation monitoring programs is another research activity designed to improve the quality of and our understanding of UVB measurements. Collocated sites will be outfitted with the standard climatological site instrumentation but may operate using measurement protocols more conducive to the network's research initiatives. For more information about network research click on the Research Activities menu item.

Data Usage Statistics

The USDA UVB Monitoring and Research Program has an extensive list of users from a wide variety of backgrounds. Please click here here for the pdf list.