Study: Direkt evidens....

http://thinkprogress.org/climate/2015/03/31/3640700/positive-feedback-except-its-terrifying/


Scientists agree that an increase in atmospheric greenhouse gases causes the Earth’s temperature to rise, but they’ve also noticed that relationship seems to swing both ways: warmer temperatures also seem to correspond with an increase in greenhouse gases......

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The Earth is currently warming at a much faster rate than previous warming events, roughly ten times faster than ice-age-recovery warming, according to NASA. In 2013, atmospheric greenhouse gas hit a record high, and scientists warned that the Earth’s ability to store and mediate gas, through plants and oceans, might been approaching its saturation point.
We’re already seeing unexpected changes in the climate: the West Antarctic ice shelves, for instance, is melting at a much faster rate than scientists predicted. “As we meddle with the climate system now, driving it to hotter temperatures, we should expect the Earth to reply by amplifying the changes we are causing,” Lenton said.