China said Saturday it had agreed with the U.S. to take up climate change and a handful of other issues, a sign of small but possible progress at recently concluded talks that were otherwise marked by acrimonious public exchanges over the divisions between the world's two largest economies. China's official Xinhua News Agency said in a dispatch from Alaska, where the two-day meeting wrapped up Friday, that China and the U.S. had decided to set up a working group on climate change and hold talks "to facilitate activities of ... diplomatic and consular missions" and on issues related to each other's journalists.

"We urgently need action on climate change, but even if we get it, there are larger issues. It’s not just climate. Humanity is overwhelming the planet, its resources and its life-supporting capacity. We are not in any danger of extinction, not yet anyway. But the human juggernaut — and the needs and aspirations that propel it — is headed for a day of reckoning," says columnist Robert Walker.

It’s no secret that city folk like to eat, shop and travel. But all that consumption adds up to a hefty climate bill. On the flip side, that means urbanites have a lot of power to rein in greenhouse gas emissions. By changing their diets, their purchasing habits and how they get around, city dwellers can help avert the worst effects of warming.