Open water at the top of the world isn't evidence that the North Pole is melting, as a recent New York Times article suggested. The hole is probably just a temporary opening in the ice pack, polar scientists say.

• Holes in the ice can close after days or persist all season, said Drew Rothrock, a polar-ice expert at the University of Washington in Seattle.

• In the Arctic, "it's not uncommon to have 10 percent open water in the summertime," added James Morison, also of the University of Washington.

• Winds and physical stress can easily fracture the Arctic pack ice, which floats in a frozen mass and is not anchored to a continent as the Antarctic ice sheet is.

Still, the ice pack has been steadily shrinking and growing thinner over decades. Records compiled by Navy submarines reveal the average end-of-summer ice thickness has slimmed from about 10 feet to 6 feet since 1958, according to data Rothrock and colleagues published recently in Geophysical Research Letters.

• Satellite measurements show that the Arctic ice pack has been shrinking by about 3 percent per decade since 1978.

• A team of Norwegian scientists recently reported in Science that multiyear ice -- which remains after the summer melt and is, on average, about three times thicker than seasonal ice -- is decreasing at a rate of 7 percent per decade.

But it's a stretch to tie any specific hole in the ice to climate change, said Mark Serreze, of the National Snow and Ice Data Center at the University of Colorado.

Source: Alexandra Witze, "New North Pole assertion may rest on thin ice; Reports of open waters in Arctic don't enhance warming evidence," Dallas Morning News, August 28, 2000.