In environmental news, the US space agency — NASA — says it’s recorded the largest hole in the ozone over Antarctica on record. Government scientists say the size of the hole now exceeds the size of North America. The development comes as the UN top’s environmental official has issued a new plea for increased efforts to curb global warming. The official, Executive Director of the UN Environment Program Achim Steiner, spoke Thursday in Beijing.

• Achim Steiner: “If the global warming trends continue at the moment–and the model suggests they are, and in fact may be doing so more rapidly–they have significant impacts on where people can live, and where people can grow food, and where people will have to leave because they can no longer live there–coastal areas. We will have disease spreading, we will have implications in terms of global trade, perhaps, nations that don’t play their part in terms of climate regime, how do they work with nations that are investing in setting their CO2 emissions. So, the potential for conflict to arise from the consequences of global warming are major trends that we now see.”

Achim Steiner’s comments ahead of next month’s summit meeting of environmental ministers in the Kenyan capital of Nairobi.