Al Gore at a TED conference. (Flickr/Creative Commons)

"I think all who look at these circumstances should agree that president Obama does have a mandate, should he choose to use it, to act boldly to solve the climate crisis, to begin solving it," Gore told the Guardian in a telephone interview.

In the wake of Hurricane Sandy’s devastation, Obama has faced increasing public pressure to deliver on his promise to act on global warming.

Gore has urged the president to immediately begin pushing for a carbon tax, which he believes could help with the “fiscal cliff.”

"He has the mandate. He has the opportunity, and he has the inherent ability to provide the leadership needed. I really hope that he will, and I will respectfully ask him to do exactly that," Gore said.

On Wednesday evening, Gore will ratchet up the pressure when he hosts 24 Hours of Reality: The Dirty Weather Report, a 24-hour live online broadcast from New York city. The message he hopes to deliver is that dirty energy has created a world of dirty weather, highlighting the implications of fossil fuels on our planet's climate, and the need to curb fossil fuel production and consumption.

The Dirty Weather Report (starting at 8pm eastern time) will kick off with footage from New Jersey's devastated shore and interviews with governors Chris Christie and Andrew Cuomo.

The former vice president’s endorsement of a carbon tax comes at a critical moment, with less than 50 days left for Congress to work out a budget deal and avoid triggering a set of automatic tax increases and spending cuts. Even some conservatives have raised the option of a carbon tax, giving hope to environmental campaigners.

After a summer of harsh drought and record high temperature, the American public opinion has also shifted. Two-thirds (67%) of Americans now say climate change is real, compared to 57% in 2009, according to a poll last month from the Pew Research Center.

In his re-election victory speech, the president named climate change as one of the top three priorities of his second term. "We want our children to live in an America that isn't burdened by debt, that isn't weakened by inequality, that isn't threatened by the destructive power of a warming planet," Obama said.

Reach executive producer Tricia Tongco here and follow her on Twitter.