Adapting to the damaging effects of climate change, plants are gradually moving to where temperatures are cooler, rainfall is greater, f...
Rapid climate changes are set to redistribute the already shrinking ozone layer, exposing earth's southern parts up to 20 percent more ultraviolet radiation in the spring and summer at high altitudes, warns a Canadian study. Concentrated in the stratosphere from 10 km to 50 km above the earth, the ozone layer protects life on the planet by absorbing more than 90 percent of deadly ultraviolet rays coming from the sun. Ultraviolet rays cause genetic changes and trigger various cancers. Toronto researchers warn that rising temperatures will change the circulation of the earth's upper atmosphere, with a marked increase in the movement of ozone from the earth's upper to lower atmosphere. However, the distribution of the ozone layer will help the Northern Hemisphere of the earth. The model showed a nine percent decrease in ultraviolet radiation hitting Northern Hemisphere's high latitudes. Reported increase in the ground-level ozone on Europe's mountains and the west coasts of North America and Europe indicates that the deadly changes predicted by the two researchers may have already begun. Interestingly, ozone is created in the earth's outer atmosphere by ultraviolet rays themselves. On entering the stratosphere, these ultraviolet rays hit oxygen molecules, breaking them into two atoms. But being unstable, each of these two atoms clings back to the oxygen molecule, thus creating ozone molecules. Greenhouse gases (nitrous oxide and hydroxyl) and chlorofluorocarbons (generated by air-conditioners and refrigerators), which are capable of rising into the stratosphere, have been blamed for the depletion of the ozone layer.
Labels: Earth/Science News