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Solar Data

The data presented in this database was collected by a joint activity between NIST and the Photobiology and Solar Radiation laboratory at Smithsonian Environmental Research Center (SERC The SERC focuses on solar Ultraviolet Radiation and its effects in ecosystems. This data is also critical to the development of service life prediction models. 

Despite being invisible to our eyes, ultraviolet radiation is responsible for most effects of solar exposure, both negative(sunburn, cancer) and positive (Vitamin D synthesis). The Ultraviolet B range, at the high energy fringe of the solar spectrum, is the most biologically active, but the lower energy Ultraviolet A is also important. UVB at the earth's surface is strongly affected by stratospheric ozone, also by clouds and air pollution. At SERC, we continuously monitor UV-B in Maryland and other locations, and investigate the ecological role of UV mainly in aquatic environments.

The SERC program uses a narrow-band, multi-filter instrument, the SR-18 which continuously monitors incident solar UV-B and short-wavelength UV-A (290-324 nm). The instruments are designed, constructed and calibrated at SERC to maintain quality control as needed to ensure consistent long-term data.

The SR-18 are the most recent products of a long-running program of solar instrument development at the Smithsonian. A previous UV-B instrument was the SR-8. Instruments of this design were in operation in Maryland (first at Rockville then Edgewater) since 1975 (Correll et al. 1992),and at Mauna Loa, Hawaii since 1984 (Neale et al., 1994a; Hofmann et al.,1995). SERC maintains a data base of 12-minute averages through the day for Maryland for the period since 1975.

Solar Data

Download *.xlsx (Microsoft Excel) files below

by location


Created September 9, 2014, Updated November 15, 2019