title: The 1995 North American Interagency Intercomparison of Ultraviolet Monitoring Spectroradiometers.
abstract: Concern over stratospheric ozone depletion has prompted several government agencies in North America to establish networks of spectroradiometers for monitoring solar ultraviolet irradiance at the surface of the Earth. To assess the ability of spectroradiometers to accurately measure solar ultraviolet irradiance, and to compare the results between instruments of different monitoring networks, the second North American Intercomparison of Ultraviolet Monitoring Spectroradiometers was held June 12 to 23, 1995 at Table Mountain outside Boulder, Colorado, USA. This Intercomparison was coordinated by the National Institute of Standards and Technology (NIST) and the National Oceanic and Atmospheric Administration (NOAA). Participating agencies were the Environmental Protection Agency; the National Science Foundation; the Smithsonian Environmental Research Center; the Department of Agriculture; and the Atmospheric Environment Service, Canada. Instruments were characterized for wavelength uncertainty, bandwidth, stray-light rejection, and spectral irradiance responsivity, the latter with a NIST standard lamp operating in a specially designed field calibration unit. The spectral irradiance responsivity, determined once indoors and twice outdoors, demonstrated that while the responsivities changed upon moving the instruments, they were relatively stable when the instruments remained outdoors. Synchronized spectral scans of the solar irradiance were performed over several days. Using the spectral irradiance responsivities determined with the NIST standard lamp and three different convolution functions to account for the different bandwidths of the instruments, the measured solar irradiances generally agreed to within 3 %.
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899-0001 USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Early
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899-0001 USA.
authors.forename: Ambler
authors.initials: A
authors.lastname: Thompson
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899-0001 USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Johnson
authors.affiliation: National Oceanic and Atmospheric Administration, R/E/ARx1, 325 Broadway, Boulder, CO 80303 USA.
authors.forename: John
authors.initials: J
authors.lastname: DeLuisi
authors.affiliation: National Oceanic and Atmospheric Administration, R/E/ARx1, 325 Broadway, Boulder, CO 80303 USA.
authors.forename: Patrick
authors.initials: P
authors.lastname: Disterhoft
authors.affiliation: Atmospheric Environment Service, Environment Canada, 4905 Dufferin Street, Toronto, ON M3H 5T4, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Wardle
authors.affiliation: Atmospheric Environment Service, Environment Canada, 4905 Dufferin Street, Toronto, ON M3H 5T4, Canada.
authors.forename: Edmund
authors.initials: E
authors.lastname: Wu
authors.affiliation: Dept. of Physics and Astronomy, University of Georgia, Athens, GA 30602 USA.
authors.forename: Wanfeng
authors.initials: W
authors.lastname: Mou
authors.affiliation: Dept. of Physics and Astronomy, University of Georgia, Athens, GA 30602 USA.
authors.forename: Yongchen
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Biospherical Instruments Inc., 5340 Riley Street, San Diego, CA 92110-2621 USA.
authors.forename: Timothy
authors.initials: T
authors.lastname: Lucas
authors.affiliation: Biospherical Instruments Inc., 5340 Riley Street, San Diego, CA 92110-2621 USA.
authors.forename: Tanya
authors.initials: T
authors.lastname: Mestechkina
authors.affiliation: Atmospheric Sciences Research Center, State University of New York Albany, 100 Fuller RD, Albany, NY 12205 USA.
authors.forename: Lee
authors.initials: L
authors.lastname: Harrison
authors.affiliation: Atmospheric Sciences Research Center, State University of New York Albany, 100 Fuller RD, Albany, NY 12205 USA.
authors.forename: Jerry
authors.initials: J
authors.lastname: Berndt
authors.affiliation: Smithsonian Environmental Research Center of the Smithsonian Institution, P.O. Box 28, Edgewater, MD 21037 USA.
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Hayes
keywords: environmental monitoring; intercomparison; solar ultraviolet; spectroradiometers