Germany: What a Lake Says About Climate Change

The power plant in the city 75 km north of Berlin had been functioning since 1966. It took some 300,000 cubic metres of water daily from the lagoon to cool down the facility's installations. The water would then be released back into the lake -- 10 degrees warmer.

Before the plant began to function scientists had declared the waters "the cleanest in Germany," says Peter Casper, biochemist at the Institute Leibniz for Water Ecology in Stechlin.