Even with the increasing summer retreats of sea ice, which climate scientists say are being driven in large part by global warming caused by humans.... (dotearth.blogs.nytimes.com)
The plight of the polar bear has been held up by environmentalists as a symbol of global warming caused by humans. (nytimes.com)
Sadly, because global warming caused by human CO2 was chosen for a political agenda, most were deliberate. (drtimball.com)