It must be tough being Al Gore.

No American has done more to raise awareness of global warming and climate change, and yet the media continue to needle him and still routinely misquote him as saying he "invented the Internet."

Until recently, even environmentalists had mixed feelings about the guy, unsure if his agenda was politics or the planet.

As U.S. vice president under Bill Clinton, Gore was often criticized for being too stiff, too boring, and a geek. In 2000, he won the popular vote, but somehow lost the presidential election.

Then, with the box-office success of "An Inconvenient Truth," the 2006 movie directed by Davis Guggenheim that he presents, things seemed to be looking up. Last month he even won an Oscar.

Inevitably, though, Gore in the limelight brought a new round of swipes from the media. One piece in particular, by William Broad in the New York Times of March 13, stirred up quite a cyberspace ruckus.

"Hollywood has a thing for Al Gore and his 3-alarm film on global warming, 'An Inconvenient Truth,' which won an Academy Award for best documentary," Broad begins. "So do many environmentalists, who praise him as a visionary, and many scientists, who laud him for raising public awareness of climate change. But part of his scientific audience is uneasy. . . . These scientists argue that some of Mr. Gore's central points are exaggerated and erroneous. They are alarmed, some say, at what they call his alarmism," he writes.

Broad's article immediately set off a lively Internet debate in blogs and articles, with writers worldwide accusing him and his sources of playing fast and loose with the facts -- exactly what Broad accuses Gore of doing.

If you've seen the film, you will have your own thoughts -- perhaps more or less critical depending on how you feel about the man himself. Personally, I'm delighted the film has attracted a global audience and raised such a fuss, if this ensures more discussion, awareness -- and careful consideration of warming and climate change.

Gore may have simplified some concepts and claims, but the truth needs to be told in a way that holds viewers' attention without boring them to tears with science. The medium of film captures people's imagination in a way others don't, and every one of us, from Beijing to Boston, needs to know what is happening to our planet.

The most reasonable criticism of the film is that it portrays the impacts of climate change with far more certainty than science can predict.

Jam with destiny

Yes, we know the planet is warming due to rising levels of warming gases in the atmosphere from human activities, such as carbon dioxide from burning fossil fuels and methane from livestock. We also know this warming will impact climate, forests, oceans, agriculture, species, glaciers and the ice caps.

But we do not know exactly what those impacts will be. We simply can't know for sure. Perhaps the impacts will be less destructive than Gore suggests; or perhaps they will be far worse.

The film could also have done without Gore's self-consciously introspective narration, and it didn't need all the shots of his rapt audiences, or the backlit shots of Gore a la rock star striding into an arena, ready for his jam with destiny.

Still, I'm delighted because Gore is telling an important part of the truth that needs to be told.

So, now, who is going to explain as convincingly all the other ways in which our society is compromising the global environment, and our children's future?

The bigger truth, the daunting truth, is that global warming and climate change are just part of the complex pattern of consumption and destruction that threatens our planet.

When we look off to the distant horizon from a mountaintop or a beach or a skyscraper, it can be difficult to understand that our planet is finite. The world around us seems so vast it is hard to imagine that human activities can have a real, lasting impact on its survival.

But as Mark Twain noted, and Gore reminds us, "What gets us into trouble is not what we don't know. It's what we know for sure that just ain't so." Incredibly, we still seem to know for sure that humans can't possibly put the planet into jeopardy, though, sadly, this "just ain't so."

Our human population has climbed to well over 6 billion and continues to grow unabated, along with our global hunger to consume ever more energy and resources.

Gore puts this in context with pictures of Earth taken from space on Christmas Eve, 1968. The images show Earth as a delicate, cloud-laced ball floating in the black vastness of space. As Gore laments, "What we take for granted might not be here for our children."

This is not simply idle lamentation. Already the world we were born into no longer exists. Technologically it has changed, in many ways to the advantage of humankind; but planetary ecosystems have changed, too, and none for the better.

As Gore notes, our generation, more than any other, is on a collision course with Earth. Millions more people mean soaring demand for food, fresh water, raw materials and value-added consumables. These demands are impacting every corner of our globe.

Species-rich forests continue to be razed for agriculture, while overused farming and grazing lands are steadily being eroded by wind and water and are, in many areas, being reduced to deserts.

Water levels in rivers, lakes and aquifers are dropping as we use more water for irrigation, for industry and for households. At the same time, the remaining water supplies continue to be degraded with agricultural and industrial chemical pollutants.

Oceans are being overfished, from coastal areas to the deep seas, and coral reefs are dying from pollution and rising water temperatures. Marine species, as well as those on land, are becoming extinct at an alarming rate.

The list goes on.

Until recently, nature always provided us with a surplus, a buffer, a way out. Whatever our trespasses against Mother Nature, she generously accepted our excesses, her seemingly endless resources and her natural systems that have cleansed our toxins from the air, water and soil, have kept us richly cared for, and blind to reality.

The inconvenient truth is that our planet is finite, while human desires are infinite. Despite the inevitability of this truth, we are still cowed by the hubris of those who tout the status quo. Of course the environment is important, they say, but the economy must come first, or human society will collapse into chaos.

But what happens when the environment as we know it collapses? Can we turn to stock markets for food, water and shelter?

A last criticism of Gore's film: He claims that warming is a moral issue not a political one. But the truth is that warming and all other forms of environmental degradation are moral issues, as well as political, economic, spiritual and cultural ones.

Planetary stability

Our environment is our world. It is the ultimate foundation of our political systems, our economies and our cultures. Without a healthy environment, none of these can survive.

According to Gore, in November 1936, in the lead-up to World War II, Winston Churchill said: "The era of procras- tination, of half-measures, of soothing and baffling expedients, of delays, is coming to its close. In its place we are entering a period of consequences."

In terms of planetary environmental stability and security, we have entered a period of consequences. Whatever we choose to do, however much or little, will determine how much is left for our children and their children after them.

This is not an idle lament. It is simply an incontrovertible truth.