Gore was the surprise guest to introduce New York City Mayor Michael Bloomberg, who spoke about the city's response to Sandy, which slammed into the city on October 29, killing 43 people, destroying homes, and knocking out power, mass transit and telephone service in huge swaths of the city.
Much of Lower Manhattan flooded from the storm surge, a danger many climate scientists warn will become more acute as the burning of fossil fuels contributes to higher global temperatures that speed the melting of polar ice, raising sea levels.
Bloomberg has long sounded alarm bells about climate change and the city's vulnerability to major storms. His blueprint for infrastructure needs, called PlaNYC, aims to cut the city's carbon footprint by 30 percent by 2030 and he has pushed to limit dependence on coal, a leading source of carbon emissions.
Bloomberg showed a picture of Gore and himself painting a city roof with white paint, a technique that keeps temperatures down and helps cut energy consumption.
The mayor also echoed some of Gore's sentiments about leadership in Washington, saying cities were "not waiting for national governments to act on climate change."
But Bloomberg added: "We had help from every part of the federal government. Everything we asked for we had. Now we've got to get some money out of them, but that's another issue."
The city has asked Washington for $9.8 billion to pay for costs from Sandy not covered by insurance or other federal funds.
Much of Gore's remarks centered on leaders in Washington, who he said had abdicated responsibility on carbon as humans treat the atmosphere as an "open sewer."
Gore, a long-time environmental advocate who served under President Bill Clinton, helped raise awareness on climate change by narrating the hit documentary "An Inconvenient Truth," which won two Academy Awards in 2007.
"Our democracy has been hacked," Gore said. "And when the large part of polluters and their ideological allies tell the members of Congress to jump, they do say, 'how high?' And we need leadership in the executive branch as well."
While saying New York must be more prepared for storms, Bloomberg was defiant that the city will not flee from its 520 miles of shoreline.
"Let me be clear: We are not going to abandon the waterfront ... But we can't just rebuild what was there and hope for the best. We have to build smarter and stronger and more sustainably," Bloomberg said.
New York state Governor Andrew Cuomo has asked for $41.9 billion in federal disaster assistance, including $9.1 billion for projects to prevent and mitigate damage from future storms.
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