Imperiled Reefs

The world's scuba divers have long known that the earth's oceans are in trouble. Pollution, rising water temperatures and tsunamis are playing havoc with coral reefs.

Cozumel, Mexico, once ranked by Jacques Cousteau as the 4th best dive site in the world, is regularly raked by hurricanes. Once the storms subside, local divers head for the reefs to try to free them of smothering sand. Reefs provide habitat for everything from moray eels to starfish.

The Cayman Islands, another popular dive site, are experiencing problems, too.

Scientists, who call this a "critical time" for coral reefs in terms of global warming, report that these reefs have lost half their hard corals in the past 10 years. This, even though for much longer than that, divers have been prohibited from wearing dive gloves, to discourage any touching of the fragile coral.

Heated sea water can kill coral, a living creature, leaving behind only a white skeleton of the once-colorful sealife that really comes alive at night. Global warming has also been linked to a reef disease called the "white plague" that researchers say is killing off coral worldwide.

The Caymans are ranked among the top 10 diving destinations in the world. Some 2-million visitors a year dive its most popular sites, such as the North Wall and Stingray City on Grand Cayman.

According to a recent Reuter's report, a United Nations panel on climate change is warning that sweeping cuts must be made in emissions of greenhouse gases, or a rise in temperatures could flood islands and coastlines under rising seas, and kill off the world's sensitive coral reefs. The president of the Central Caribbean Marine Institute on Little Cayman Island, Carrie Manfrino, predicts, "We could see the end of coral reefs in our lifetime."

Limiting warming to no more than 3.6 degrees Fahrenheit (2 degrees Celsius) would cost the world .012 percent of its annual gross domestic product, the U.N. panel says.

Cayman Island reefs are still thought to be among the healthiest in the Atlantic, thanks to the islands being "isolated" from the pollution of other countries with offshore waters 6.000 feet deep.

Meantime, a new study finds that global warming is speeding up the disintegration of arctic ice shelves. Researchers at the Snow and Ice Data Center (www.nsidc.org) and the National Center for Atmospheric Research (www.ncar.edu) in Boulder, Col., have reviewed more than 60 years of data recorded by ships, airplanes and satellites, estimating the maximum and minimum area of Arctic sea ice.

The ice normally expands most in March, shrinking most in September. Since 1953, September sea ice has shrunk almost 8 percent per decade - 6 percent more than U.N. estimates. If greenhouse gases are not kept in check, the researchers say, the ice may disappear even faster.

Melting ice contributes to rising ocean levels.