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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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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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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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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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.
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