Ultraviolet Radiation in the Arctic: 2012-2015

Biospherical Instruments Inc (BSI) has operated NSF’s Ultraviolet Spectral Irradiance Monitoring Network (UVSIMN) between 1988 and 2008. The network included three locations in Antarctica, two in the Arctic (Barrow, Alaska, and Summit, Greenland) and two mid-latitude sites. In 2009, the instruments at Barrow and Summit have been integrated into NSF’s Arctic Observing Network as part of the AON projects “Ultraviolet Radiation in the Arctic” and, since 2012, “Ultraviolet Radiation in the Arctic: 2012-2015.” The award is jointly overseen by Prof. John E. Frederick of the University of Chicago and Dr. Germar Bernhard of BSI and will end on 31-August 2015. To date, the network has produced one of the longest Climate Data Records (CDR) of UV radiation in existence. Measurements at Barrow span the 21-year period of 1991-2012. Measurements at Summit started in 2004 and are ideally suited to probe the free troposphere and study the effects of long-range transport of pollutants and aerosols on UV radiation. Data can also be used for validation of satellite observations, verification of models describing the transfer of radiation through the atmosphere, advancement of climate models, and addressing the SEARCH question such as whether the Arctic is moving to a new state. Data have been used by hundreds of researchers investigating the effects of stratospheric ozone depletion and other climatic factors on UV radiation at the Earth’s surface and subsequent consequences on aquatic and terrestrial ecosystems, and humans. Several researchers from other AON projects have used data. Recently, data were used to interpret radiosonde and LIDAR observations at Summit as part of the AON project “High Resolution, Active Remote Sensing of Cloud Microphysics at Summit, Greenland with Polarized Raman Lidar” (NSF Award 1303864) and to calibrate down-welling irradiance measurements at Summit in support of the AON project “Direct radiative forcing over central Greenland - assessment of the coupled effect of light absorbing aerosols and snow albedo variability” (NSF Award 1023227) [Wright et al., 2014]. Spectral UV data from Barrow have recently been used to interpret a massive phytoplankton bloom observed in the Chukchi Sea under first-year sea ice in 2011 [Palmer et al., 2014].