
_JB:_ That?s according to “Betsy Weatherhead”:http://cires.colorado.edu/science/groups/weatherhead/ of the University of Colorado in Boulder. She and a colleague reviewed satellite data and found that, over the past decade, the ozone layer stopped thinning and in some places appears to be growing. They attribute the turn-around to the 1987 Montreal Protocol, an international treaty that banned ozone-destroying chemicals.
_Betsy Weatherhead:_ I’m absolutely impressed not so much as a scientist, but I’m just impressed as a citizen of the Earth. This was a global problem. It was a real threat to the environment and as a result of the collaboration between scientists, policy makers, chemical manufacturers and even everyday citizens, we ended up arresting the problem and we’re starting to see the Earth as a whole improve.
_DB:_ Experts believe it could take 50 more years – at least – for the ozone layer to recover completely. Meanwhile, said Weatherhead – because of the increased risks of skin cancer and cataracts – people should still limit their exposure to UV radiation by wearing hats, sunglasses and sunscreen.
_Betsy Weatherhead:_ No one should be thinking, “Great, I can throw out that sunscreen, I never liked it to begin with.” No one should interpret these results that way.
_JB: Our thanks today to “NASA”:http://www.nasa.gov/externalflash/nasa_gen/:_ explore, discover, understand. We’re Block and Byrd for “Earth & Sky”:/http://208.96.63.114/.
Our thanks to:
Betsy Weatherhead
Atmospheric Scientist
NOAA’s Earth System Research Laboratory
Boulder, Colorado
Mark Jacobson
Environmental Fluid Mechanics and Hydrology
Department of Civil and Environmental Engineering
Terman Engineering Center
Stanford University