The White House on Tuesday released its third National Climate Assessment. The bottom line? “Global climate is changing and this is apparent across the United States in a wide range of observations,” the report says. “The global warming of the past 50 years is primarily due to human activities, predominantly the burning of fossil fuels.” Read the full report here. “Climate change is not a distant threat,” John Holdren, director of the White House Office of Science and Technology Policy, said in a CNN story yesterday. “It already is affecting every region of the country and key sectors of the economy.”