September 17, 2009

Climate change may mean less UV radiation

Canadian scientists say climate change will lead to less ultraviolet radiation in some northern areas, such as Siberia, Scandinavia and northern Canada.

Physicists at the University of Toronto said they have discovered changes in the Earth's ozone layer due to climate change will reduce the amount of ultraviolet radiation in northern high latitude regions, while other areas of the Earth, such as the tropics and Antarctica, will instead face increasing levels of UV radiation.

Using a sophisticated computer model, postdoctoral fellow Michaela Hegglin, Professor Theodore Shepherd and colleagues determined 21st-century climate change will alter atmospheric circulation, increasing the flux of ozone from the upper to the lower atmosphere and shifting the distribution of ozone within the upper atmosphere.

They said that will result in modifying the amount of UV radiation reaching the Earth's surface -- up to a 20 percent increase over southern high latitudes during spring and summer, and a nine percent decrease in UV radiation over northern high latitudes, by the end of the century.

The scientists said decreased UV radiation could have adverse effects on vitamin D production for people in regions with limited sunlight such as the northern high latitudes.

The study appeared in the Sept. 6 issue of the journal Nature Geoscience.