World Powers Vowed to Cut Greenhouse Gases. They’re Still Rising Perilously.

“ Four years after countries struck a landmark deal in Paris to rein in greenhouse gas emissions in an effort to avert the worst effects of global warming, humanity is headed toward those very climate catastrophes, according to a United Nations report issued Tuesday, with Chinaand the United States, the two biggest polluters, having expanded their carbon footprints last year.

“The summary findings are bleak,” the report said, because countries have failed to halt the rise of greenhouse gas emissions even after repeated warnings from scientists. The result, the authors added, is that “deeper and faster cuts are now required.”