Abstract
Climate affects inland waters in many ways, with temperature and freezing being the factors most sensitive to climate change. Water temperature and ice cover are regarded as indicators of the global warming and climate variations; these records analyzed as environmental issues have gained prominence in recent years. In this article, the author summarizes papers on the temperature and ice conditions of lakes, rivers and springs.
In the latter half of the 20th century, the average temperature of lakes has risen at rates between 0.01°C and 0.06°C per year in many regions of the world. Warming tendency is also found in rivers. Dates of freeze-on in lakes and rivers have occurred about 6 days later over the recent 100 years, and dates of ice break-up occur about 6 days earlier. In addition to long-term warming trend, middle or short-term variations corresponding to El Nino-Southern Oscillation and North Atlantic Oscillation have been detected. Warming trends have also become evident in groundwater and spring temperatures.
