Crisis Planet Earth

CRISIS PLANET EARTH: Global warming poses a continuing threat to our planet's survival. That's why NASA scientists Dale Quattrochi and Jeff Luval use the latest space age technology. In this program, the explorers travels to Salt Lake City, Utah and to the Costa Rican rain forest to examine data from scientific instruments that measure the earth's rising temperatures. In the second half of the program, INTO THE DEPTHS, host Bill Kurtis and a group of environmentalists descend to the bottom of Lake Superior, the world's largest body of fresh water, to measure the damage caused by pollutants. An environmental scientist from the University of Minnesota discovered a special current that sweeps the lake clean, cleansing itself of pollutants.

• documentary