Diminishing water resources are becoming of increasing concern because in many countries the sources of drinking water are close to being exhausted. Therefore, there is an urgent need to study and assess the various components of global water resources, of which freshwater lakes are one of the most important. This book discusses contemporary limnological problems on a local, regional and global scale with special emphasis on the application of remote-sensing techniques to monitor lake dynamics, thermodynamics, biodynamics and water quality. An interactive approach is used to assess various processes from both the numerical modelling and observational standpoints. The authors recommend a combined use of in situ and remote-sensing data, giving a specific comparative analysis of the lakes of north-western Russia and the American Great Lakes as an illustration. The role of GIS is discussed and emphasised.