This year's Antarctic ozone hole is the smallest one since 1988, but this has little to do with earthly activities and much to do with weird weather in the stratosphere, U.S. Government scientists have said. The ozone hole has also split into two pieces, a new wrinkle on a phenomenon that scientists first observed in the 1970s, and have tracked as one measure of the impact of pollution. The 2002 edition of the ozone hole covers about 16 million sq. km, well below the 24 million square kilometres seen for the last six years at this time of year.