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Vanishing Into Thin Air
by Peter Tyson

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Glaciers are shrinking worldwide. Does it matter?

In Ernest Hemingway's "The Snows of Kilimanjaro," the dying protagonist imagines himself ascending to a summit "great, high, and unbelievably white in the sun." Alas, that line will soon have an air of the quaint, for according to glaciologists who are monitoring the situation with a collective resignation, Kilimanjaro's year-round snows—that is, its storied glaciers—will be gone in 15 years, perhaps sooner.

There may still be the relict patch of ice, and new snow will continue to whiten the 19,340-foot summit for four to six months of every year. But the ice fields that have graced Africa's Everest for 12,000 years will have vanished like a mirage in the dry plains below. Nor are Kilimanjaro's glaciers alone in their plight. Outside of Antarctica and Greenland, whose mass balance of ice is not well known, the vast majority of mountain glaciers on Earth are, like routed armies, in full and in many cases accelerating retreat.

Over the years I've paid my respects to glaciers from the Rockies to the Himalaya, from Baffin Island in the arctic to Anvers Island in the Antarctic. But when I asked myself why it should worry us that ice on remote mountaintops is fading away, I found myself slipping surprisingly easily into the role of devil's advocate. I say "surprisingly" because for every other threatened environmental resource I could readily think of—rain forests, old-growth forests, coral reefs, endangered species, open land, the ozone shield—the reasons for concern with their disappearance seemed obvious.

Not so with glaciers. After all, most people in the world live far from glaciers. What's the difference if all that water is frozen up there or melted down here? Don't retreating glaciers mean more available land? And wouldn't we be more likely to find more cool stuff like lost planes, preserved mammoths, Ice Men?

In short, aside from the aesthetic loss, which is clear enough in the case of Kilimanjaro's vanishing snow fields, does it really matter that glaciers in the Andes have dwindled by as much as 25 percent in recent decades? That Glacier National Park in Montana has gone from 150 glaciers a century ago to 35 today? That, according to researchers at the University of Alaska Fairbanks, Alaska may be losing anywhere from 15 to 31 cubic miles of ice a year?

After talking to a number of glacier experts, I got the intellectual comeuppance I knew I was in for. It matters, and here's why:


Nature's reservoirs

Glaciers store 80 percent of the world's freshwater in their ice. People in many countries, including the U.S., depend on meltwater from glaciers and the annual snow pack to supply water for quenching thirsts, irrigating fields, and watering industry. These frozen assets collect snow during the wet times of the year and release it slowly as meltwater during drier times, just when farmers need it most. Slowly is the key word here: we need glaciers to melt, just not as fast as they're now doing.

In arid parts of Central Asia, including some important drainage basins in western China and all of the "'stans," glacial meltwater provides most of the available surface water during certain parts of the year. Two years ago, according to Russian glaciologist Vladimir Mikhalenko, Kyrgyzstan and Uzbekistan almost went to war over glacial melt from the Tien Shan mountains, whose western stretches lie in Kyrgyzstan.

Small potatoes, you think? What if such countries are nuclear armed? "It's not written down anywhere that it's glaciers they're fighting over," geologist Jeffrey Kargel says of India and Pakistan's conflict in glacier-rich Kashmir. "But that's at least a major contributor to it." Kargel, who directs GLIMS, or Global Land Ice Measurements from Space, a consortium of 24 nations that is monitoring the world's glaciers by satellite, says that next to Uzbekistan, Pakistan depends on glacier meltwater perhaps more than any other nation on Earth.

And not just for water but for electricity. Descending meltwater from glaciers and snow packs produces about a fifth of the world's electricity. Melting of Andean snow fields is already having an impact in Peru, which boasts three-quarters of the planet's tropical glaciers. A case in point is that country's Rio Sante electric power plant. These days power production at the plant is 100 percent in the wet season but drops to 20 percent in the dry season. "They make up for the lack of power on the grid by building fuel-burning power plants in places like Lima to meet the needs of the population," says Lonnie Thompson, a senior research scientist at Ohio State University's Byrd Polar Research Center.


Mounting losses

The result, of course, is more air pollution. Many scientists believe more heat-trapping gases mean more global warming, which means more glacial melting. More glacial melting means more need for fuel-burning plants, which means more pollution. It's a vicious cycle, and one that will likely become even more vicious as populations expand.

There are other environmental impacts as well. Glacier meltwater nourishes many alpine ecosystems, which would be severely impacted without it, and certain desert streamside habitats would completely collapse without its arrival in the dry season. With revegetation taking a longer time at high altitude, erosion could increase. And all that water once stored in ice contributes significantly to sea-level rise, the feared bane of coastal communities everywhere. If the roughly 24,000 cubic miles of ice stored in mountain glaciers were to melt, Thompson says, it would raise oceans by a foot and a half worldwide, displacing an estimated 100 million people in Bangladesh alone. Where would they go?

Glaciers also serve as archives of past climate, which scientists can use to predict future climatic trends. Kilimanjaro's ice is particularly valuable, being the only source for tropical ice-core data in all of Africa. Soon, however, the only place you'll be able to study Kilimanjaro's ice will be at Thompson's ice-core lab in Ohio.

Other reasons for concern are more localized but for local people no less worrisome. Melting could trigger more glacier-related disasters like the one that struck the Russian village of Karmadon in September 2002. In that incident, a hanging glacier broke off from a mountain, either because it grew too heavy or because it melted at the point where it attached to the rock, Kargel says. The collapse sent 20 million tons of ice, rock, and mud onto the village, killing more than 100 people.

Glacier countries can suffer in more subtle ways. Kilimanjaro is the number-one foreign currency earner for the government of Tanzania, says Thompson, whose team drilled ice cores from the mountain's glaciers in 2000. "A real debate has gone on in their Parliament since we did our research there about how many tourists will continue to come to Kilimanjaro when there's no ice on the equator," he says. (Kilimanjaro lies about 200 miles south of the equator.) Countries in the Alps have already felt a sting from glacier loss, he adds, with tourism having dropped about 10 percent over the past decade or so.


What to do?

If you agree with me that the glacier experts answered my initial question in spades, then you're probably wondering, as I did, what can be done. In Kilimanjaro's eleventh-hour case, some have gone so far as to suggest wrapping the summit glaciers, Christo-like, in a giant reflective blanket. "The idea is perhaps a bit optimistic," says Douglas Hardy, a University of Massachusetts climatologist whose team is actively monitoring the mountain's glaciers. "I don't know if there's really anything that can be done."

Sadly, the same holds true for other tropical glaciers and perhaps for their temperate and even arctic counterparts. If, as many glacier experts suspect, greenhouse gases are causing global warming and consequent glacier melting, the ball is already in play. "These gases remain in the atmosphere for 100 years after being released," says Thompson. "Even if we decided tomorrow that this is a real problem and we'll work together in a global effort to reduce carbon dioxide emissions, I think the inertia in the system—the gases are already there—will mean that Kilimanjaro's ice fields will disappear, as will a lot of the ice fields down through the Andes."

In addition to the reasons cited above, something of inestimable value will have been lost. "There is the grand dome [of Kilimanjaro], with its snow cap glancing and scintillating like burnished silver," the English explorer Joseph Thomson wrote upon first catching sight of the mountain in 1883. "What words can adequately describe this glimpse of majestic grandeur and godlike repose?"

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Summit crater

Marble-white beacon to travelers for thousands of years, Kilimanjaro's ice cap has shriveled by more than 80 percent since 1912.

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Glacier National Park

Icefields are disappearing not just in the tropics but in temperate and even arctic zones. Scientists predict, for example, that Glacier National Park, which lies along the U.S.-Canadian border in northern Montana, will have lost its eponymous glaciers in 30 years.

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Bhutan glaciers

Glaciers in the Himalayas are dwindling at rapid and accelerating rates. Along with satellite and historic data, a key indicator is the rapid and widespread appearance of lakes atop the ice fields, as can be seen in this satellite image of Bhutan's glaciers.

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Qori Kalis 1978-2002

Peru's Qori Kalis, the largest glacier draining the world's largest tropical ice cap, retreated more than two football-field lengths between 2000 and 2001, a rate 40 times faster than it was during the period 1963 to 1978. The country is already feeling the effects.










Volcano Above the Clouds
Vanishing Into Thin Air

Vanishing Into Thin Air
Glaciers are shrinking, not just on Kilimanjaro but worldwide. Does it matter?

Tour Kilimanjaro

Tour Kilimanjaro
Visit the peak's six ecological zones, from steamy rain forests to arctic summit.

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The Seven Summits
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Peter Tyson is editor in chief of NOVA online.



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