SPATIAL DISTRIBUTION OF LAKE LADOGA SURFACE TEMPERATURE IN ICE-FREE PERIODs: MEAN AND ANOMALOUS VALUES
Based on the empirical data obtained during 43 expeditions in ice-free periods in 1960-2003, anomalous deviations deviations in real Lake Ladoga surface temperature fields from the typical ones are analyzed. Real surface temperature distributions are designed for each of 43 data sets and compared with the corresponding typical ones. Statistical significance of calculated deviations is shown and their limits are estimated. The anomalous deviations in real surface temperature from the typical pattern are mapped. An analysis of these maps is carried out, which allows us to reveal the heterogeneous character of spatio-temporal anomalities of Lake Ladoga surface temperature fields. Areas and time periods with minimum and maximum anomalous deviations, mean value of surface area corresponding to typical temperature distribution and characteristic degree of anomality are defined. Some causes for the revealed character of Lake Ladoga surface temperature fields anomality are analyzed.