(Recasts, adds comments from Austria, Lesotho, Cape Verde)

By Alister Doyle, Environment Correspondent

VIENNA, Aug 26 (Reuters) - The United Nations says momentum is building for broader long-term action to fight global warming beyond the U.N.'s Kyoto Protocol and a climate meeting starting in Vienna on Monday will be a crucial test.

About 1,000 delegates from more than 100 countries at the Aug 27-31 talks will seek common ground between industrial nations with Kyoto greenhouse gas caps until 2012 and outsiders led by the United States and China, the top two emitters.

"Momentum is very much building," for global action, Yvo de Boer, the U.N.'s top climate change official, said of the meeting of senior officials, scientists and activists. "And Vienna's going to be crucial."

"The coming week will give us an indication of whether the political community ... is willing to move beyond well-intentioned platitudes towards real negotiations," he told a news conference on the eve of the talks.

"The fight against climate change must be broadened," Austrian Environment Minister Josef Proell said, welcoming U.S. willingness to take part in a long-term U.N. deal to cut emissions mainly from burning fossil fuels.

Vienna will try to break a diplomatic logjam and enable environment ministers to agree at a meeting in Bali, Indonesia, in December to launch formal two-year negotiations to define stiffer long-term curbs on greenhouse gases.

But while delegates talk about talks, many worry that climate change is already taking its toll, especially in developing nations heavily dependent on agriculture.

"We have a very dangerous situation developing," said Lesotho's Minister of Natural Resources Monyane Moleleki. "For the past 30 years climate change has been spooky to say the least."

DROUGHTS

The number of severe droughts in southern Africa had doubled since 1978 compared to the rest of the 20th century, he said. "And when the rains come they come in deluges, torrents that are useless."

"Cape Verde is an island state, hit by all vulnerabilities of climate change," said Cape Verde Environment Minister Madalena Neves, pointing to risks such as rising seas and desertification.

Chances of a deal in Bali have risen sharply after U.N. reports this year blamed human activities, led by use of fossil fuels, for a changing climate set to bring ever more severe heat waves, droughts, erosion, melting glaciers and rising seas.

And President George W. Bush, a Kyoto opponent, agreed in June with his industrial allies on a need for "substantial cuts" in greenhouse gas emissions. It is unclear exactly what "substantial" means for Washington.

The European Union, Japan and Canada have all talked about a need to halve world emissions by 2050 to slow warming.

Many nations want a "Bali road map" agreed in Indonesia -- a two-year plan to work out a deal to succeed Kyoto, which obliges 35 industrial nations to cut emissions by 5 percent below 1990 levels by 2008-12.

A road map could include principles that a deal should include major emitters, that it should not undermine economic growth in developing nations and that rich nations should take the lead, delegates say.

Even though there are five years left until 2012, many experts say time is already running short. Anyone planning to build a coal-fired power plant, or to invest in carbon markets, wants to know the long-term rules.

AlertNet news is provided by