In contrast to the troposphere, the stratosphere is extremely dry and practically cloudless - the concentration of water vapor is measured in parts per million and is, in fact, comparable to that of ozone.

Beginning in 1986, a series of field experiments were designed to test the various hypotheses which had been put forth to explain the Antarctic ozone hole.

Laboratory experiments, field observations and atmospheric modeling calculations have now established that chemical reactions occurring on PSC particles play a central role in polar ozone depletion.

In fact, we just surpassed our first 1 million simultaneous users online.

Climate change and ozone depletion are two global issues that are different but have many connections. In the ozone depletion case, we managed to work with decision makers effectively so that an international agreement called the Montreal Protocol was achieved that essentially solved the ozone depletion problem.

Plans to protect air and water, wilderness and wildlife are in fact plans to protect man.