The climate change debate continues. Are anthropogenic causes of global warming responsible for melting ice and rising seas or are natural cycles and climate variations to blame? There’s no question that Greenland’s glaciers are in fact melting. And while the obvious culprit may be global warming caused by rising carbon dioxide emissions, University of Washington atmospheric scientists have estimated that up to half of the recent warming in Greenland and surrounding areas may be due to climate variations. The kicker? These climate variations originate in the tropical Pacific and are not connected with the overall warming of the planet.