<http://schema.org/alternativeHeadline>
"Carbon dioxide remains the most significant threat, but slow government action has scientists looking at other culprits to combat."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/wilderness-resources/stories/want-to-slow-sea-level-rise-curb-these-4-pollutants>