Estimating the Great Lakes net radiation using satellite remote sensing and MERRA reanalysis

Abstract

The net all-wave radiation of the Great Lakes (GL) is a key to understanding the effects of climate change on the GL. There is a high possibility of underestimating the net all-wave radiation of the GL when using existing methodologies with inputs from near-shore and land-based meteorological data. This study provides the first technique to estimate net all-wave radiation over the GL from July 2001 to December 2014 using a combination of data from satellite remote sensing, reanalysis data sets, and direct measurements. The components of the surface radiation budget estimated from the proposed method showed good statistical agreement. The instantaneous net radiation estimated by our methods was compared with the in situ measurements from June 2008 to April 2012 (Stannard Rock Lighthouse: SR) and September 2009–April 2011 (Spectacle Reef Lighthouse: SP). The comparisons from SR and SP also showed strong statistic agreement (R2 = 0.74 and 0.7; RMSE = 9.26 and 10.60 W m−2 respectively). Monthly spatial variations of net shortwave radiation varied with cloud cover and surface albedo while net longwave radiation varied with the temperature difference between the water surface and the atmosphere.