By Alister Doyle and Stian Reklev
WARSAW (Reuters) - Haiti, the Philippines and Pakistan were hardest hit by weather disasters in 2012, a report issued at U.N. climate talks on Tuesday showed, as the death toll mounted from the latest typhoon to devastate the Philippines.
Germanwatch, a think-tank partly funded by the German government, said poor nations had suffered most from extreme weather in the past two decades, and worldwide, extreme weather had killed 530,000 people and caused damage of more than $2.5 trillion.
"The unfolding human tragedy caused by super typhoon Haiyan will only be captured in future reports," said Soenke Kreft, a co-author of the report issued on the sidelines of November 11-22 talks among almost 200 nations trying to reach a deal by 2015 to slow global warming.
Super typhoon Haiyan, one of the most powerful storms ever recorded, slammed into the Philippines on Friday and killed an estimated 10,000 people in one coastal city alone. The toll is expected to rise sharply as rescue workers reach remote areas.
The report for 2012, based on an index of fatalities and economic damage from weather extremes, noted that Haiti was struck by Hurricane Sandy, the Philippines by typhoon Bopha and Pakistan had suffered severe monsoon floods.
A U.N. panel of climate scientists predicts that a build-up of planet-warming greenhouse gases in the atmosphere, mainly from human use of fossil fuels, will cause ever more droughts, floods, heatwaves and rising sea levels.
Major tropical storms are a hard riddle for climate scientists to solve. Most say it is impossible to put an individual event, such as typhoon Haiyan, down to climate change. However, the United Nations Intergovernmental Panel on Climate Change (IPCC) says "it is more likely than not" that storms will increase in intensity in the coming century.
One thing is fairly concrete, said Will Steffen, executive director of the Australian National University Climate Change Institute - climate change is causing surface waters to warm, which in turn feeds more energy into storms.
Scientists also say rising sea levels - about 20 cm (8 inches) since 1900 - can worsen storm surges.
Negotiators are in Warsaw to lay the groundwork for a U.N. climate pact, meant to be agreed in 2015 and enter into force from 2020, to cut greenhouse gas emissions.
On Tuesday, about 30 climate activists joined a fast by Philippine Climate Commissioner Naderev Sano, the nation's top delegate in Warsaw, who said on Monday he would not eat until a "meaningful outcome" was reached.
Some activists would fast during the meetings, but eat in the morning and evening, said Wael Hmaidan, director of Climate Action Network. He said he was among those fasting full time and would "continue until we see political movement or until the end" of the meeting.
Sano said he hoped his fast would put pressure on delegates to agree a new loss and damage mechanism to compensate poor countries for damage from global warming. He also urged more action by developed nations to curb their emissions and raise climate aid towards a promised $100 billion a year from 2020, from about $10 billion a year in 2010-12.
Most developed nations, however, are focusing on spurring economic growth after the financial crisis, rather than stepping up efforts to confront climate change.
Germanwatch said Haiti lost 9.5 percent of its economy last year in weather disasters led by Hurricane Sandy.
(Additional reporting by Michael Szabo; Editing by Janet Lawrence)