THE ozone layer over the US had thinned to unprecedented and worrisome flimsiness during 1993, say scientists who had monitored sunlight at various ground sites over the year. Between January and April of last year, ozone concentration was 12.6 per cent below normal (New Scientist, Vol 142, No 1927).

What is worrying scientists is the ozone loss in the summer months -- when there is more sunlight to contend with and thus greater risk from skin cancer-causing ultraviolet (UV) radiation. The team from the University of Colorado and the National Oceanic and Atmospheric Administration lab, both at Boulder, Colorado, says that the amount of UV radiation during summer months may have shot up to 17 per cent the normal.