Temporary Gain Seen in Ozone Layer Over North Pole

The protective ozone layer over the North Pole appears to have stabilized after years of thinning, but the gain may be temporary, U.N. weather experts said this week. Scientists from the World Meteorological Organization said the recovery may be attributed to a warmer than usual winter and the current peak in the 11-year cycle of the sun, and not to cuts in the worldwide use of harmful chemicals. The sun is now moving back into an 11-year period of declining radiation, meaning the production of ozone will be at its lowest in 2006.

--Compiled by Times medical writer Thomas H. Maugh II