Related: Environment

1. More environment
   1. Got water? Keeping it flowing could get expensive
   2. World population could hit 11 billion by 2100
   3. Endangered California frogs let loose in wild
   4. 2012 natural disaster costs one for record books
   5. Largest solar sail ever to launch in 2014
2. More U.S. news
   1. Bulger witness: We were 'up to our necks in murder'
   2. NSA: Surveillance thwarted NYSE, subway bombings
   3. Fliers tackle passenger screaming about poison, CIA, Snowden
   4. Analysis: Why Edward Snowden isn't a 'whistleblower'
   5. 'Key milestone': US, Taliban to finally meet
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