A US government monitoring station shows that we have pushed atmospheric carbon dioxide levels to 400 parts per million for the first time in human existence, reports Joe Romm at Climate Progress. Simultaneously, a truly remarkable set of paleoclimate data, published in the peer-reviewed journal Science, shows that climate is much more sensitive to carbon dioxide than we thought. Based on Arctic sediment core samples, different types of evidence indicate carbon dioxide levels roughly 3 to 5 million years ago were similar to present ones, but the Arctic temperature was much warmer, about 14 degrees Fahrenheit warmer, and sea levels were 82 feet higher. Previous models fail to show such climate sensitivity to carbon dioxide levels, and indeed, current models fail to predict the far faster melting of Arctic ice now occurring. What does this mean for our civilization? Romm, a scientist himself, says it means that returning as quickly as possible back to 350 ppm is a vastly more rational course of action for a non-suicidal civilization, than continuing our unrestrained march toward carbon dioxide levels of 600, 800, and even 1000 parts per million.
Join the swelling numbers of voters TELLING Congress they’ll vote for Clean Energy candidates here: http://signon.org/sign/we-are-the-clean-99?source=c.em.cp&r_by=487176 . This is an ongoing campaign (the next Congressional election is in 2 years!) so please, spread the word. It’s our way of telling Congress that a strong clean energy voting bloc is out there. This is how YOU can make a difference.
For more on Climate Change, check out my weekly column at the HuffingtonPost, Climate Change This Week : http://www.huffingtonpost.com/author/index.php?author=mary-ellen-harte
Climate Sensitivity Stunner: Last Time CO2 Levels Hit 400 Parts Per Million The Arctic Was 14°F Warmer! http://thinkprogress.org/climate/2013/05/12/1993531/climate-sensitivity-stunner-last-time-co2-levels-hit-400-parts-per-million-the-arctic-was-14f-warmer/