the amount of summer sea ice in the arctic has steadily declined over the past few decades because of man-made global warming, according to the national oceanic and atmospheric administration.
the amount of summer sea ice in the arctic has steadily declined over the past few decades because of man-made global warming, according to the national oceanic and atmospheric administration.
scientific consensus on climate change:69
the global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases.