Severe Storms From Washington DC to New York City
May 23, 2013; 7:34 PM ET
The same system that spawned deadly tornadoes in Oklahoma has reached the Northeast. more >
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The same system that spawned deadly tornadoes in Oklahoma has reached the Northeast. more >
May 23, 2013; 5:00 AM ET A team has developed a model to determine the influences of humans and climate on vegetation changes. Valerie Smock explains what has the greatest effect.