British Prime Minister Gordon Brown called Gore "inspirational." French President Nicolas Sarkozy said he was happy that "a great American used his position to set an example." European Commission President Jose Manuel Barroso said he hoped Gore's honor would encourage world leaders to "approach this challenge even more swiftly and decisively."

In winning the Nobel Peace Prize, Gore completed an unusual trifecta of awards for the year. The movie "An Inconvenient Truth," which highlighted his climate change crusade, won Oscars for best documentary and best original song. Gore also won an Emmy for the interactive work of Current TV, a cable channel he helped found.

The Nobel committee described Gore as "probably the single individual who has done most to create greater worldwide understanding of the measures that need to be adopted."

The award came seven years after Gore lost his bid for the White House when a bitter recount in Florida and a narrow Supreme Court decision effectively ended his campaign and put President Bush in office. Gore won the popular vote, and his failure to win the presidency was a blow that took him many months to get over.

From that searing experience, he has built a new career in which he has mixed business ventures with his long-standing interest in technology and the environment to emerge as the most visible advocate for confronting threats to the planet from global warming. Along the way he has also made himself wealthy, largely through investments in technology firms such as Google.

Sen. John F. Kerry, D-Mass., who sat in the first Senate climate change hearings along with Gore back in 1987, recalled Friday how little interest those hearings generated. "This is a very important statement of transition on a global level," Kerry said. "It's not only a tribute to Al's work, but a wakeup call to the administration and the U.S., who has been the global delayer on this."

Gore watched the Nobel announcement live at 2 a.m. (PDT) while overnighting in San Francisco. Spokeswoman Kalee Kreider said he realized he had won only when he heard the name "Gore" coming through from the Norwegian official.

Gore was in California for meetings of the Alliance for Climate Protection, a nonprofit advocacy group he helped establish to change public opinion and generate action by individuals. He said he and his wife would donate his share of the $1.5 million award to the group.

While Gore received most of the public accolades, IPCC officials also celebrated the award Friday. IPCC Secretary Renate Christ, who discovered the panel had won only after checking the Nobel Prize Web site at 11 a.m. Geneva time, said the panel had fulfilled its mission of providing "balanced and unbiased information" about climate change. "Policymakers have to take the final decision of how to respond to the knowledge," she said.