Ambitious Paris climate deal needs more than what 195 nations have pledged

Climate change is the type of problem where delay is especially costly. It is not like other pollution such as dirty urban air or a putrid stream

A mounting sense of urgency will greet negotiators as they arrive at this year’s United Nations Climate Change Conference in Poland. In 2015, after 20 years of trying and failing to reach a global accord on climate-changing emissions, 195 nations hammered out a deal, the Paris Agreement, that all of them could accept.

Three years on, it’s becoming increasingly clear that national decisions about climate action, which country negotiators will convey in Poland and over the next two years, will determine whether the breakthrough Paris pact succeeds both on a political and emissions reduction front.

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