Abstract
The assumption of M. Milankovich about the constancy of the Earth's albedo during the interglacial period was replaced with the alternative one. The model was developed where anomalies of the average annual temperature of the surface atmosphere were related with interannual changes in the planetary albedo and the thermal inertia of the hydrosphere. The surface temperature changes due to albedo actual and model changes were calculated. Possible external causes of albedo changes were considered.