California, long a national leader in cutting auto pollution, pushed the envelope further Friday as state regulators approved rules to cut greenhouse gas emissions from cars and put significantly more pollution-free vehicles on the road in coming years.

In this spine-country of grandeur and extremes, where people often mark time by natural events such as "the year of the big flood," this is the year of the weird winter. Even with California's volatile weather, where exceptions are the rule, the season has been the driest in 30 years. Without snow, hotels are offering rock climbing and archery to frustrated skiers.

A relief mission through perilous, ice-choked seas was the first mid-winter fuel delivery to Alaska, capping a year of pioneering shipping as oil and gas development and climate change increase traffic along northern trade routes sought by centuries of Arctic explorers.

Rainfall patterns over east Africa have changed in a way that makes severe droughts more likely - and this means aid agencies need to rethink the way they operate.

Climate change this century poses both risks and opportunities, according to the first comprehensive government assessment of its type. The report warns that flooding, heatwaves and water shortages could become more likely. But benefits could include new shipping lanes through the Arctic, fewer cold-related deaths in winter and higher crop yields.