Estimation of the short-wave incoming radiation from AVHRR data on the Arctic Ocean

An empirical method to estimate the solar incoming radiation has been improved using AVHRR (Advanced Very High Resolution Radiometer)-NOAA14 data in the framework of the ARTIST (Arctic Radiation and Turbulence Interaction Study) experiment. This method, using several bulk formulas, gives an estimation of the incoming solar radiation and results are compared with the surface-based and aircraft-based measurements. The first step of the method is the development of a cloud detection algorithm for the area and for the period of interest. The area is the Arctic Ocean near the Svalbard Islands and the period is from 15 March to 16 April 1998, the transition period from winter to spring and in this particular case from the Polar Night to a period of quite normal insolation. Several bulk formulas, right for the Polar condition, are tested comparing the estimate insolation fluxes with the direct measurements made with a pyranometer mounted aboard the Polar2 aircraft and an other pyranometer at the research base at Ny-Alesund. The comparison could define the best parameterization for the available data.