Governor Tom Corbett's administration has proposed new regulations designed to bring the state's air quality up to national standards, but some coal plants will be able to pollute 40 percent more than they do now.
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The ozone hole fluctuates in size every year due to natural meteorological variations, but no shrinking trend can yet be seen. However, scientists are confident the Montreal Protocol is working in the long-term, and could be used to limit super pollutants that contribute to global warming.