It is “time for a national oil change,” said Al Gore with a sly wink in his voice. “That is apparent to anyone who has looked at our national dipstick.”

“Freeze right there!” says Gore.

Photo: David Lodge/WireImage

This was one of the few moments of comedy in what was billed as a “major policy address” yesterday by the former veep. In an uncharacteristically formal speech to students, faculty, and a throng of top reporters gathered in a New York University auditorium, Gore — after a year spent chronicling the climate crisis in lectures, film, and print — turned to the subject of solutions. He outlined a host of policy proposals both familiar and strikingly new, rarely interjecting quips of the sort that have consistently endeared him to audiences in recent months.

“My purpose is not to present a comprehensive and detailed blueprint [of future climate policy], for that is a task for democracy as a whole,” intoned Gore, “but rather to try to shine some light on a pathway through this terra incognita that lies between where we are and where we need to go.”

The pathway Gore described began with “immediately freezing [carbon dioxide] emissions and then beginning sharp reductions.” Reminiscent of the nuclear freeze of the ’70s, Gore’s proposed carbon freeze “has the virtue of being clear, simple, and easy to understand,” he argued. “It can attract support across partisan lines as a logical starting point for the more difficult work that lies ahead.”

Standing against a stately backdrop of American flags — gone were the flashy visuals that usually accompany his climate speeches — Gore projected a decidedly more somber and serious persona than the exuberant, almost giddy character we’ve seen pumping his fists and cracking jokes as he roared around the world on his climate lecture circuit. It was a persona that, if you squinted just right, seemed almost …

Yes, presidential. Indeed, Gore’s protestations that he has no intention of becoming a 2008 presidential contender have been getting weaker. Add to that the recent news that Gore will be publishing a book next May entitled The Assault on Reason — a meditation on the ineptitude of political leaders paralyzed by their “unwillingness to let facts drive decisions” — and it’s enough to drive the media to distraction.

Little wonder, then, that rumors have begun to circulate that the White House may announce a major new climate policy in order to steal Gore’s gathering thunder. (If Karl Rove can convince Bush to turn on his buddy Michael Crichton, you know the Republican Party senses shifting winds.)

Despite its formality, Gore’s speech focused on uplift: “Many Americans are now seeing a bright light shining from the far side of this no-man’s land that illuminates not sacrifice and danger,” he said, “but instead a vision of a bright future that is better for our country in every way — a future with better jobs, a cleaner environment, a more secure nation, and a safer world.”

Such effulgent optimism is new. The whole lecture, in fact, seemed a response to the most common criticism levied against Gore’s climate presentations — that they are too clouded with doom and gloom, failing to convey a hopeful, can-do message (despite his frequent observation that the climate crisis presents equal parts danger and opportunity).

With the exception of a mention at the outset of yet more evidence of rapidly melting polar ice caps, the speech focused entirely on solutions. In fact, it was an exhaustive laundry list of dozens of such solutions, with no shortage of wonky detail, and peppered with assurances to the tune of, “This is a major source of hope!”

Many we’ve heard before: so-called stabilization wedges, as outlined by Princeton professors Stephen Pacala and Rob Socolow, which would solve the climate crisis with an array of existing technologies; the “25 x ’25” proposal from the agriculture community, which would dramatically expand the use of biofuels and renewable energy; increasingly affordable and effective solar panels, wind turbines, and green architecture; “flex-fuel, plug-in, hybrid vehicles” that can run on gasoline, biofuels, and electricity; and a decentralized electricity grid with smaller generators located closer to the points of use.

Also back, in vaguely retro fashion: Kyoto. Gore argued that the U.S. is obligated to play a lead role in developing a new global treaty on climate change. “Since the [Kyoto] treaty has been so demonized in America’s internal debate, it is difficult to imagine the current Senate finding a way to ratify it,” he said. “But the United States should immediately join the discussion that is now underway on the new, tougher treaty that will soon be completed. We should plan to accelerate its adoption and phase it in more quickly than is presently planned.”

Some unexpected, outside-the-box proposals popped up as well. One he has been advocating “for the last 14 years,” he said (to the surprise of many who remember no such proposal in, say, the 2000 campaign), would eliminate all federal payroll taxes — Social Security and unemployment compensation included — and replace the revenue with a pollution tax on CO2. “The overall level of taxation would remain exactly the same,” explained Gore. “It would be, in other words, a revenue-neutral tax swap. But instead of discouraging businesses from hiring more employees, it would discourage businesses from producing more pollution.”

He also proposed a new Carbon Neutral Mortgage Association — a wonky idea redeemed by a cute nickname, “Connie Mae” — to help finance more efficient buildings and eventually zero-energy, zero-emission architecture. Builders often bypass efficient features like thicker insulation and better windows, Gore noted, because these investments elevate construction costs on the front end, even though they pay for themselves within a few years. “It should be possible to remove the purchase-price barrier for such improvements through the use of innovative mortgage finance instruments,” he said.

Throughout the address, Gore’s calls to action were couched in a thick layer of patriotism: “In order for the world to respond urgently to the climate crisis, the United States must lead the way. No other nation can … Our natural role is to be the pace car in the race to stop global warming.”

Could the U.S. shift from obstructionist to leader on global-warming policy? It sounds far-fetched, perhaps, but no more so than the notion that climate change — once the exclusive obsession of environmentalists and climatologists — could catapult a man once written off as a historical footnote back into the presidency.