NSF Office of Polar Programs UV Spectral Irradiance Monitoring Network (UVSIMN): 2009

The National Science Foundation (NSF) Ultraviolet (UV) Spectroradiometer Network was established in 1987 by the Division of Polar Programs in response to serious ozone depletion reported in Antarctica. Biospherical Instruments installed the first instruments in 1988 and has operated the network continuously since. The network was the first automated, high-resolution UV scanning spectroradiometer network in the world. It continues to successfully operate in the harshest environments on Earth (Antarctica and the Arctic), and is currently providing data to researchers studying the effects of ozone depletion on terrestrial and marine biological systems. Network data is also used to ground-truth satellite observations, develop and verify models of atmospheric light transmission, and evaluate ozone depletion impacts. The network currently consists of seven SUV-100 scanning spectroradiometers installed at three sites in Antarctica (McMurdo Station, Palmer Station, and South Pole Station), one site in Argentina (Ushuaia, Tierra del Fuego), two sites in the United States (Barrow, AK, and San Diego. CA) and one in Greenland (Summit Station). The San Diego site is a multi-purpose system facility, and used for training site operators, testing new configurations, and collecting data. Dependent on the time of the year, solar scans are conducted quarter-hourly when the sun is above the horizon. A complementary GUV filter-detector spectroradiometer is part of the system, which provides one minute averaged global irradiance values at several UV wavelengths. Ancillary data (Eppley PSP, Total Scene Irradiance (TSI) sensor, various system temperatures, and monochromator position) are collected over 24 hours at intervals ranging from 1 to 60 minutes. Data are collected on a reduced schedule at night. At sites inside the Arctic or Antarctic circles, instrument operation is on a reduced scan schedule during the winter darkness. Dependent on internet bandwidth and connection reliability, objectives for data availability are: -Real-time data updates (hourly - limited due to bandwidth) from the GUV filter-detector radiometers. This data will have one-minute resolution (an average of 60-120 samples per channel, per minute), of 30+ data products, available as it is for our other sites (except Ushuaia, where a fixed-IP full time internet connection is cost prohibitive). - Weekly updates of "preliminary" data from the SUV scanning spectroradiometers, as available at: www.biospherical.com/nsf/login/update.asp. - Post-processed, final QA/QC'd data products, including full spectra, are made available on a schedule to be determined – typically annual. These data are characteristically the same as what can be obtained at www.biospherical.com/nsf/login/login.asp. - Additional data products; weighted integrals, preliminary spectra, etc. from the SUVs, with greater frequency of availability, in support of specific scientific protocols.