A team of 78 researchers from 60 institutions in the international network PAGES (PAst Global Changes) has “published the most comprehensive reconstruction of past temperature changes at the continental scale” over the past 2000 years, reports Joe Romm at Climate Progress. Their Nature Geoscience article concludes that those 2000 years represented a global cooling trend, which ended in the late 19th century. The so-called Medieval Warm Period and Little Ice Age were regional, not global in scope, although generally cold conditions pervaded for 3 centuries from the mid 1500s to the late 1800s, with occasional regional warmer punctuations. The transition to these colder conditions occurred earlier in the Arctic and Eurasia than in North America or the Southern Hemisphere regions. Recent warming has reversed this long-term cooling. The average temperature between 1970 and 2000 was higher than any other time in nearly 1,400 years; between 1980 and 2010, it was higher still. This means it’s getting hotter, faster. A graph of temperature across time over the past 2000 years, shows for the last 60 years what is called “the hockey stick” by climatologists, a dramatic upswing in global temperature.
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
The Hockey Stick Lives: New Study Confirms Unprecedented Recent Warming Reverses 2,000 Years Of Cooling Wednesday http://thinkprogress.org/climate/2013/04/23/1903001/the-hockey-stick-lives-new-study-confirms-unprecedented-recent-warming-reverses-2000-years-of-cooling/