If present trends continue, most climatologists agree that the concentration of carbon dioxide in the atmosphere will have doubled by the year 2050. This increase in CO 2 will have a major effect on the global climate and substantially alter the physical, chemical and biological characteristics of lakes throughout the world. In recent years, it has become clear that year-to-year changes in the weather have a major effect on the seasonal dynamics of lakes. Many water quality problems that were once regarded as "local" phenomena are now known to be influenced by changes in the weather that...