Number 51 (Story #2), October 10, 1991 by Phillip F. Schewe and Ben Stein LEVELS OF STRATOSPHERIC OZONE OVER ANTARCTICA are at a record low. NASA scientists reported that the total ozone mapping spectrometer (TOMS) on board the Nimbus-7 satellite measured an ozone level of only 110 Dobson units (units indicative of the atmosphere's ability to absorb light) on October 6, 1991, as compared to a level of 500 units which is typical at other times. Scientists fear that decreased ozone levels, and a consequent increase in solar ultraviolet radiation reaching the earth's surface, may lead to increased skin cancers. (The New York Times, 10 October 1991.) Indeed, levels of solar ultraviolet radiation measured at Palmer Station on the Antarctic Peninsula in December 1990 were twice as large as in previous years. (Geophysical Research Letters, October 1991.)