Changes in Earth’s Albedo Measured by Satellite

The albedo of Earth, i.e., the fraction of the global incident solar radiation that is reflected back to space, is a fundamental parameter of global energy balance. Using earthshine data, recent report claims to have detected a large increase in albedo, although not over the entire solar spectrum from 0.3- to 4-µm wavelength. The earthshine results are primarily for visible wavelengths and represent about half of Earth's surface. The global CERES observations show a small decrease of about 2 W m-2 in shortwave reflected flux, equal to an albedo decrease of 0.006. These results stand in stark contrast to thearthshine results, which show a large increase of 6 W m-2 or an albedo increase of 0.017.