Odds are that the U.S. will remain a party to the Paris climate accord former Vice President Al Gore said Wednesday In a brief appearance at the TED conference in Vancouver.

"I think there is a better than 50-50 chance the Trump administration will decide to stay in the Paris agreement," Gore said. "I don't know that for sure."

Gore said there is a debate taking place tomorrow inside the White House with a decision set to be announced the third week in May before a G-20 summit. "I think the odds are they will decide to stay in Paris agreement. I certainly hope so."

The backdrop: Gore's comments came during an entire session devoted to the impact on climate change. Discussions ranged from more accurate pictures of the crisis to weighing radical solutions, including shooting chalk into the atmosphere in order to reduce the amount of sunlight heating the earth. That idea drew criticism from Gore and others.