The latest report from the United Nations climate change body, released Tuesday, makes clear the good, the bad, and the ugly about one of the world’s most intractable problems.

As things stand today, the world will be hard pressed to limit greenhouse-gas emissions and avoid the worst effects of global warming during the rest of the century. That’s the ugly.

In the twenty-odd years since global warming leapt on the international stage at the Earth Summit at Rio de Janiero global greenhouse-gas emissions have not only kept growing, they’re growing at an ever-faster clip. That’s the bad.

Now, the world’s hopes for limiting temperature increases and minimizing catastrophes such as rising sea levels and devastating droughts depend to a large extent on what steps developing economies take to fundamentally change the way they use energy. And that, curiously enough, could be the good.

On Tuesday, the final, full draft report from Working Group III of the International Panel on Climate Change came out. (U.N. officials had released tidied up, trimmed down summaries of that latest consensus among climate scientists over the weekend.) The report’s purpose is not to dive into all the contentious and sometimes controversial science behind climate change, but rather to lay […]