United States Department Of Agriculture (USDA)
	Colorado State University (CSU) / Natural Resource Ecology Laboratory (NREL)

The USDA’s Cooperative State Research, Education and Extension Service (CSREES) is supporting research and monitoring programs to determine the potentially damaging long-term and short-term effects of enhanced UV-B ultraviolet radiation on agricultural crops and forests. As part of this research initiative, Colorado State University (CSU) is establishing a nationwide surface UV-B monitoring program. It measures primarily ultraviolet radiation, 300-368nm, with multiple instrumentation spanning 280-940nm, in units of Watts/meter^2/nm.

With a network of 32 sites in USA [29], Canada [2], and New Zealand [1], located primarily in rural areas, with particular consideration given to agricultural and forested regions. Our web site gives details about the variety of instrumentation we are using [view web site].

Instrumentation consists of seven-wavelength (300, 305, 311, 317, 325, 332, and 368 nm) 2nm FWHM filter shadowbanded radiometer to measure total horizontal, diffuse, and direct normal irradiance. This is similar to visible MFRSR. The instruments are operated and data is acquired over a phone line.

In order to provide information on the geographical distribution and temporal trends of UVB 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.

Our usable UV data begins in 1998, so we don't yet have sufficient baseline data to reliably determine any trends. In the meantime, we have a wide range of UV impact research problems being addressed by the Impact Group coordinated by Dr. Wei Gao. We have developed extensive collaboration and interaction with researchers in agriculture, natural resources, and science communities, some of whom are addressing trends. Many of our current research projects using this UV data are ongoing, long-term projects.

A 3-Dimensional model was developed to predict the UV-B and UV-A irradiance for horizontal surfaces in open canopies. The model can serve as a much needed tool to examine UV loading of people and other life in and below tree and other vegetation canopies.