<http://schema.org/about>
"The IPCC as an organization is prohibited from making specific policy prescriptions -- confining itself to the science of climate change -- but the most recent IPCC report did say that 450ppm should be the absolute"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/corporate-responsibility/ipcc-chairman-personally-backs-350ppm-co2-targets-holding-temperature-rise-to-15ac.html>