In this book, scientists from eleven countries summarize the results of an EU project (CLIME) that quantified the effects of observed and projected changes in the climate on the seasonal dynamics of lakes in Northern, Western and Central Europe. Historical measurements from eighteen sites are used to compare the seasonal dynamics of the lakes and assess their sensitivity to local, regional and global-scale changes in the climate. Simulations using a common set of models, perturbed by two different Regional Climate Models, were then used to assess the uncertainties associated with water quality projections produced for the period between 2070 and 2100. The book includes chapters on the phenology and modeling of lake ice, the supply and recycling of nitrogen and phosphorus, the flux of dissolved organic carbon and the seasonal succession of phytoplankton. There are also chapters on the coherent responses of lakes to changes in the atmosphere, the development of a web-based Decision Support System and the implications of climate change for the Water Framework Directive.