(AP) -- The brutal heat waves that killed thousands of Europeans in 2003 and that choked Russia earlier this year will seem like average summers in the future as the Earth continues to warm, the U.N. weather agency said Tuesday.
The last decade confirmed scientific predictions of 20 years ago that temperatures will rise and storms will become more fierce - and those trends are likely to continue, said Ghassam Asrar, who heads the climate research center at the World Meteorological Organization.
The WMO was due to release details on the last decade's global temperatures later this week at the U.N. climate conference in this Caribbean resort city, but Asrar said it was the warmest on record.
Scientists say the warming trend is caused mainly by industrial pollution accumulating in the atmosphere and trapping heat. Negotiations conducted under U.N. auspices have been trying to find ways to reduce greenhouse gas emissions to keep temperatures from rising to levels likely to have disastrous consequences.
While it is difficult to attribute any single weather event to climate change, extreme events are becoming more common. Judging by the current trend, the unprecedented heat wave that scorched Europe in 2003 and Russia this July will seem cool by the end of the century, Asrar said.
"There is no question the past three decades have become progressively warmer," he said. "We are on an upward trajectory."
Although climate science is still evolving and learning from current patterns, Asrar said government planners should plan for a warming world.
In 2003 an estimated 35,000 to 40,000 people died from heat-related ailments or incidents, in the hottest summer since 1540. Russia's summer this year was the warmest this century and ignited peat fires in the forests around Moscow that suffocated the capital for weeks. Temperatures soared into the 30s Celsius (90s F) in normally chilly Siberia.
This year witnessed freakish weather, both heat and extreme cold, the WMO said. Records for low temperature were shattered in hundreds of U.S. locations, and heavy snowfall disrupted air and road traffic in Europe, the U.S. and China. Pakistan suffered floods that killed 1,700 people and displaced 20 million people. China also had unusually high temperatures, floods and landslides.
In Venezuela, President Hugo Chavez called recent extreme weather swings there an example of climate change. The country suffered a severe drought early this year, and now is in the midst of deadly floods occurring past the traditional end of the rainy season.
"These are the big climate changes, the big disturbances that make the dry seasons, the wet seasons unpredictable," Chavez said Monday on state television.
Venezuela and Bolivia were among a handful of countries that blocked a non-binding climate accord from being formally approved at last year's U.N. summit in Copenhagen. Chavez, who blames capitalism for climate change, said they plan to take a critical position in Cancun on "the responsibilities that the so-called developed world should assume."
Chavez has not said whether he will attend this year's conference. Bolivian President Evo Morales plans to join the summit Dec. 9, Pablo Solon, the country's chief delegate at the talks, said Tuesday.
Negotiators at the two-week Cancun conference have a limited agenda of agreeing on the first steps to help poor countries deal with changes in climate and develop their economies in low-carbon ways. A key issue is to create a body to govern and distribute $100 billion dollars in climate aid for poor countries by 2020.
Delegates agreed at the last climate summit in Copenhagen last December to funnel $30 billion over the coming three years for "fast track" financing for poor countries who need immediate help. Projects include coastal management against ocean surges, help for small scale farmers whose traditional crops are ruined by changing weather patterns and to governments to help them plan for low-carbon growth.
The European Union said Tuesday it has mobilized euro2.2 billion ($2.9 billion ) this year, and is on track to meet its pledge of euro7.2 billion over three years in "fast track" financing. U.S. delegate Jonathan Pershing said Monday Washington has allocated $1.7 billion for 2010.
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