"I think we already know enough to predict that the outcome in Paris is going to be successful. Even the text that they are working on, it's light years ahead of any previous negotiations," the former US vice president-turned climate activist told AFP in the French capital.
"The French have done an excellent job in organising it, but nations all over the world have learned the lessons of the past and are preparing for a bright future," he added.
Gore said a critical mass of social mobilisation bode well for the 195-nation UN summit from November 30 to December 11.
"In every great social movement for change, those who have advocated for the necessary and the just change have faced the challenge of convincing others to do the right thing," he said.
Negotiators in Paris will aim to strike a bargain that limits global temperature rise to two degrees Celsius (3.6 degrees Fahrenheit) over pre-industrial times by limiting greenhouse gas emissions from burning fossil fuels.
Talks in 2009 in Copenhagen, which also sought to craft a world climate rescue pact, ended in failure and confusion.
A slideshow presented by Gore about the dangers of climate change was the basis of the popular 2006 documentary "An Inconvenient Truth," which won two Academy Awards.
