The United States'production of other industrial chemicals that erode the earth's protective ozone shield, the largest output in the world, is being phased out, and the shield is expected to recover in time.
12.
Unlike some of their cousins, which are dwindling worldwide from habitat destruction, pesticide pollution of their breeding grounds and ultraviolet light penetrating Earth's thinning ozone shield, bullfrogs seem to be holding their own.
13.
The metaphors used in the CFC discussion ( ozone shield, ozone hole ) resonated better with non-scientists and their concerns . damage to plants, and reduction of plankton populations in the ocean's photic zone.
14.
Two Americans and a Dutch citizen who is based in Germany were awarded a Nobel Prize in Chemistry on Wednesday for their pioneering work in explaining the chemical processes that deplete the earth's ozone shield.
15.
Smuggled CFC gas from India has been seeping into the United States by the ton, allowing American motorists to stay cool for less in the summer but prolonging the threat to the Earth's ozone shield.
16.
They now have to rely on increasingly shaky data from QuikTOMS's aging predecessor, the 6-year-old TOMS ( Total Ozone Mapping Spectrometer ) satellite, to monitor the battered ozone shield that protects us from harmful ultraviolet rays.
17.
The specific metaphors used in the discussion ( ozone shield, ozone hole ) proved quite useful and, compared to global climate change, the ozone case was much more seen as a " hot issue " and imminent risk.
18.
Less severe but marked depletion of the ozone layer has also begun to occur over the Arctic during the northern spring, and there has been pronounced thinning of the ozone shield even over temperate regions in recent years.
19.
Representatives of more than 100 governments agreed last week to phase out developed countries'production of methyl bromide, an agricultural pesticide that had been the only industrial chemical responsible for weakening the earth's protective ozone shield not previously designated for elimination.
20.
Last week, for the first time ever, the Royal Swedish Academy of Sciences awarded a Nobel Prize to scientists for work on an environmental problem _ in this case, the role of industrial chemicals in weakening the earth's protective ozone shield.
