PropertyValue
?:author
?:citation
?:datePublished
  • 2015-05-18 (xsd:date)
is ?:itemReviewed of
?:keywords
?:mentions
?:text
  • This March, for the first time in human history, the monthly average carbon dioxide in our atmosphere exceeded 400 parts per million. The range had been 170-300 parts per million for hundreds of thousands of years. (en)
rdf:type