I remember the exact moment. It was December 2006. A friend of our family stood at our doorstep, bearing cookies, the gifts of the season. This warm, maternal, quintessential mother also bore a copy of the hit documentary “An Inconvenient Truth.” I was puzzled.

Our friend was a staunch Republican and an evangelical Christian. But like many who saw the film, she changed her mind about climate change and set out convincing others with the zeal of a convert. This was a sign to me that every dog has his day, and Al Gore’s had just arrived.

Putting climate change aside, this decade’s political scene gave us plenty to talk about. An ex-cocaine user turned business failure turned President of the United States destroyed his political party and nearly took the country with them. Financial regulations were dramatically rolled back, which opened the door to speculation and risk-taking that was irrational and ultimately disastrous. Barack Obama provided a positive counterpoint. Astonishingly, this son of Hawaii beat the odds and won the White House.

Climate change cast its global shadow over all of this. Within the past 10 years, climate change has skyrocketed as an issue of national and international importance. In 2000, the memory of the U.S. Senate’s 98-0 rejection of the Kyoto Protocol was fresh. Now it seems distant and foolish.

Over the past 10 years, the climate change issue has entered our daily lives. We had the “green Oscars,” considered “green jobs” and watched “The Day After Tomorrow.” We’ve learned new words and terms, from “carbon footprint” to “hybrid car.” Even the term “climate change” is new, reflecting the fact that man-made climate disturbances manifest themselves not only in “global warming,” but also in a variety of different disturbances.

The people of New Orleans learned firsthand about the disastrous variety. Hurricanes, so prevalent in that part of the country, are fed and fueled by warm ocean waters. In recent years those waters warmed more than usual, enough to intensify hurricanes such as Katrina, which devastated New Orleans. The Crescent City wasn’t the only place where climate change made itself known recently.

This decade, a Kofi Annan-led think tank estimated that about 300,000 people died each year from climate change-related causes. Annan’s report found that access to safe food and drinking water has been impaired by desertification, changing rainfall patterns and rising sea levels due to climate change. Malnutrition, malaria and diarrhea became the ultimate fate of millions of people.

At the forefront of this cultural and moral awakening was a man who had a terrific decade: Al Gore.

Gore was, at first glance, an unlikely candidate have such a great 10 years. The decade started poorly for him, with the dubious 2000 election turning Gore into something between liberal folk hero and national joke. He grew a beard and put on weight. But around mid-decade, something about Gore changed.

He quit running for president. He hosted “Saturday Night Live,” had fun and looked relaxed. Hours later he announced he was not getting into the 2004 presidential race as had been rumored. The former vice president’s main mission was now brought into sharp relief.

Gore crafted a compelling “slide show” about climate change that made him a global icon. The “slide show” was the focus of “An Inconvenient Truth,” which became one of the most successful documentaries in American history. So powerful were Gore’s presentation and the film’s art that even firm opponents of Gore’s previous political aspirations were swayed to accept the reality of man-made climate change. The film won an Oscar. A star was born.

Gore did not slow down, and neither did his movement. As if Oscar gold wasn’t enough, Gore shared the 2007 Nobel Peace Prize with the Intergovernmental Panel on Climate Change. Climate change activists brought all manner of pressure to bear on institutions to induce eco-friendly practices. Olympic hosts and aspiring host cities, for instance, are falling over themselves to make their games the “greenest ever.” Gore was the public face and leading light of it all.

Think back to New Orleans. This city’s saga demonstrates Gore’s main contribution to public discourse — his formulation of climate change as a “moral issue.” As we watched television images of human beings stranded, bodies floating and dogs roaming the streets of an American city, the ethical dimension of climate change came into sharp relief.

Many lives have been grievously affected by man-made climate change, and more hang in the balance. Gore recognized that the world has a moral obligation to prevent this mass misery from coming to pass. What excuse will we give those who suffer? When our cities and homes are washed away, what excuse will we give ourselves?

This was truly Al Gore’s decade. Because its public profile was amplified, because of the changes it has already made in our lives, and because of its potential to alter civilization, climate change was this decade’s paramount issue. Gore, standing at the movement’s vanguard, was its public face and energizing force. He made global warming cool, and, at last, made Al Gore cool. It’s about time. Besides, I’d rather spend a climate crisis with Al Gore than Jake Gyllenhaal.