Research Objectives:
This project is an experimental study of solar radiation processes near the surface at Dome Concordia (Dome C), the French-Italian station in East Antarctica. It will be carried out in cooperation with the Laboratoire de Glaciologie et Geophysique de l'Environment in Grenoble, France. The emphasis is on the reflection of sunlight by snow and the transmission of sunlight through clouds. The observations researchers gather will be relevant to climate, remote sensing, and the physics of ice and snow.
Observations of the angular pattern of solar radiation reflected from the snow surface will allow the researchers to validate information derived from satellite-derived radiances. Using radiative transfer modeling through the atmosphere, the project's research team will reconcile measured surface reflection functions with the empirical functions obtained from the Advanced Very High Resolution Radiometer on the polar orbiting NOAA satellites.
Since Dome C is at 75 degrees latitude, the optical properties of the snow surface can be observed at higher solar elevation than is possible at the south pole. Researchers are also exploring the possibility that the Dome C region is the optimum antarctic surface for use as a calibration target for earth-observing satellites.
The research team will measure transmission of solar radiation through clouds, and these measurements will be used to obtain effective cloud optical depths to estimate cloud radiative forcing, with applications in climate models. They will develop a method to obtain this information from pyranometers alone so that the historical record of solar radiation observations in the antarctic interior can be analyzed for climatological information on clouds. Finally, the spectral peak of snow albedo will be accurately located in order to resolve a discrepancy over the spectral absorption of pure ice in the visible to near-ultraviolet range.
