U.N. report editor - Managing risk in a warming world

WASHINGTON (Reuters) - One of the most interesting facets of a new United Nations climate change report is what's not in it: much mention of curbing the greenhouse gas emissions that trap heat in Earth's atmosphere and in turn can spur some natural disasters.

"It is a change," said Christopher Field, a top editor of the 600-page document released on Wednesday. "This report does focus on managing the risks of extreme disasters rather than changing those risks. Changing the risks is the mitigation agenda."

The mitigation agenda was central to a 2007 report by the U.N. Intergovernmental Panel on Climate Change (IPCC), whose key finding was that, with 90 percent probability, climate change is occurring and human activities contribute to it.

The latest report from the IPCC focuses instead on how to make people and their assets - homes, farms, stores, office buildings, infrastructure - more resilient to the intense droughts, floods and storms projected for the coming decades.

"We were asked by the governments (of the world) to focus primarily on the time frame that's relevant for disaster risk reduction, which is mostly the time frame of one to a few decades," Field said in a telephone interview.

"That's a time frame where most of the climate change that will occur is already baked into the system and where even aggressive climate policies in the short term are not going to have their full effects," said Field, who is director of the Carnegie Institution's department of global ecology.

Mitigation is still important, he said, but the risk to life and property is happening now or soon, and while no single natural disaster can be attributed solely to climate change, the increased floods, droughts, heat waves and other dangerous events are in line with projections of what a warmer world could bring this century.

While some parts of the world are particular prey to extreme weather events -- such as heavy precipitation in the northeastern United States and droughts in the southwestern United States, southern Europe and western Africa -- nowhere is free from climate risk, he said.

"There are some clear regional patterns ... but it's important to know that we don't see any places in the world that are out of harm's way," Field said.

Two factors that heighten the risk of natural disasters are vulnerability (the predisposition that people will be hurt) and exposure (the sheer number of people, jobs, services and other assets likely to be in the path of the severe event), he said.

The United Nations report was released one day after the U.S. Obama administration proposed long-delayed rules to cut emissions of climate-warming carbon dioxide from new power plants, a move expected to be contested by the energy industry.