We have now reached the point where global warming skepticism is as absurd and dangerous a philosophy as Holocaust denial. The problem is manifest, and most people who are paying attention have recognized that the earth's climate is radically changing. Even the Bush administration has accepted this as an indisputable truth. Unfortunately, far fewer people have come to the realization that it will affect humanity.

This is partly the fault of environmentalists. To a Sierra Club member, a statement that the ecosystem is being destroyed has harrowing connotations. But, to many people, it simply means that a few species of animals they don't eat anyways are going to die off. We humans, they might say, have developed civilization and transcended the ecosystems we evolved into. We have cities, supermarkets, and cars. How can a few degrees of global temperature change affect us? A few feet rise in sea level? A handful of bigger storms?

Certainly on of the most obvious dangers is the rising water level. It is important to understand that many of the world's biggest and most populous cities are built on coasts and rivers. A global water level rise of twenty feet would sink all of Alameda, for example, and a good portion of Manhattan. In Asia, it would mean the displacement of millions of people. Remember the scene from "Gandhi" on the India-Pakistan border in 1947. It wouldn't be that bad. It would be worse. People would lose everything they owned.

It's not—quite—all bad, though. Global warming could open up a sea route that's been unusable for almost a millennium: the Northwest Passage through the (formerly) permanent Arctic ice shelf. This would make it far easier for supertankers, too big for the Panama Canal, to reach the west coast. That's right; supertankers carrying the crude oil that causes global warming have the most to gain from allowing it to continue.

Besides the world's most severe refugee problem, though, there are several more socioeconomic dangers. The spread of disease, for instance, could wreak havoc in countries where the populations have developed no immunity to illnesses that had not existed in the region before. Think of the smallpox plague that decimated Native American populations in the seventeenth century. Not good.

Of course, worsening storms will cause billions of dollars of damage, in addition to contributing to the refugee problem and killing countless people. In fact, the Association of British Insurers has estimated that by the 2080s, reducing carbon emissions could save 80% of the damage done by hurricanes and tropical storms. This is a very reliable source; they have a corporate interest in understanding disaster.

So, as I've heard several people eloquently put it, "global warming is bad." Need I say more?