By Roger K. Lewis
Saturday, August 5, 2006
We have to see Alaska before it melts -- that's what we jokingly told friends before we headed north last month.
But this was not entirely a joke. Alaska's melting glaciers have been likened to the "canary in the mineshaft," a warning sign that the planet is warming. The glaciers we saw were convincing evidence that things are indeed heating up.
Perhaps you interpreted this week's heat wave as another sign that the planet is heating up. But it's likely that you have been less worried about global warming than about staying cool and keeping your electrically powered air conditioner functioning.
This illustrates the challenge posed by climate change: Can modern civilizations cope with a global rather than a local threat, a truly worldwide phenomenon requiring coordinated international policies and actions? What will it take to persuade diverse populations and governments to acknowledge the threat and take steps to reduce or eliminate it?
Until we visited Alaska, signs and effects of global climate change seemed remote and abstract to me. Here in the nation's capital, even this year's bizarre climate patterns -- drought, record-setting torrential downpours, floods, intense heat -- don't necessarily lead one to think globally.
"Think globally but act locally" sounds nice, but most people think and act locally, and short term to boot. This is why efforts to conserve resources and energy, reduce pollution, and decrease carbon dioxide emissions remain fragmentary and marginal. The scale and complexity of the problem are enormous. Most of the world's societies, including ours, resist acknowledging the problem and refuse to seriously tackle it.
Of course, we didn't go to Alaska to think globally. We went primarily to see spectacular mountain ranges capped by ice fields and glaciers a mile thick, dramatically rugged seacoasts lacerated by thousand-foot-deep fiords, and broad valleys and plains carpeted with spongy tundra and countless species of colorful wildflowers. We went looking for Alaska's abundant wildlife: grizzly and black bears, moose, caribou, wolves, foxes, bald and golden eagles, puffins, beavers, sea otters, sea lions, whales and, in this fisherman's paradise, halibut and salmon.
But looking at shrinking glaciers along Alaska's coast and seeing undeniable evidence of increasingly rapid glacial melt makes you a believer: The planet is getting warmer. You don't have to be a scientist to observe how much the massive glaciers have retreated in a relatively short time. You can stand atop a moraine -- a low, meandering ridge of boulders, gravel, sand and dirt dropped by glaciers along the line where they stopped advancing and began receding -- and sense how many billions of cubic feet of ice have vanished.
Fortunately, the science is not difficult to understand. A glacier retreats and shrinks when the amount of ice lost during summer months exceeds the amount of winter snowfall feeding and replenishing the glacier's ice supply at higher elevations. In a single year, the face of a glacier can retreat dozens of feet. Over decades, the retreat can measure hundreds or even thousands of feet.
Scientists worry about glacial melting and global warming with good reason. The volume of water stored in the world's glaciers and ice fields is so great that sea levels would rise several meters if a significant portion of the ice melted. Low-lying coastal lands around the world would be inundated.
Scientists also worry that, as global warming continues unabated and ever more quickly, many fertile regions of the world will become arid and less agriculturally productive. Much of the planet's plants and animals, including humans, will be displaced or forced to adapt to rapidly changing and potentially destructive environmental conditions, such as hurricanes.
Global warming is the result of increasing amounts of atmospheric carbon dioxide, which traps solar heat. The increase is directly attributable to human activity, because carbon dioxide is a byproduct of burning fossil fuels to produce energy.
Even worse, as the earth's energy-hungry population generates more carbon dioxide, it is also clearing away, either for farming or urbanization, more of the earth's natural vegetation. Through photosynthesis, vegetation absorbs carbon dioxide and emits oxygen.
Slowing down or reversing global climate change requires reducing the amount of carbon in the earth's atmosphere. There are only two ways to achieve this: Decrease the use of fossil fuel globally and increase vegetation globally. But because water and air ignore political boundaries, this can be achieved only through a global effort on a global scale.
Experiencing Alaska does make you think about the fate of the planet. Yet it also made me think about the Washington region, thousands of miles away. I wondered whether we were heading for a future in which, after the glaciers in Alaska and elsewhere melt, portions of Washington, Alexandria, Annapolis and Baltimore disappear. I wondered if the District's avenues and streets will be lined with palm trees.
Then, if the salmon are still running, it might be time to move to Alaska.
Roger K. Lewis is a practicing architect and a professor of architecture at the University of Maryland.