glaciers

1The Intelligent Citizen’s Guide to His World: Glaciers

Glaciers perform naturally a role comparable to mankind’s dams and reservoirs: they lock up fresh

water. And, like dams, they number in in the scores of thousands, big and little, all over the world.

But, unlike dams and reservoirs, glaciers are disappearing while dams are multiplying. So significant a

role have they played in our world that we should understand what caused them, how they have waxed

and waned, why we need them and why today they are disappearing. I begin with their origin as set

out by the National Climatic Data Center (NCDC) on April 6, 2009.

As we all experience, the climate of the Earth goes through yearly seasonal changes. As it moves

around the Sun, the northern and southern hemispheres swap positions relative to the sun so their in-

take of solar energy varies. This march of the seasons happens because the Earth is tilted off the vertical

axis in relation to the sun. If there were no tilt, we would have no seasons. The degree of tilt, however,

is not fixed. It varies between 22º and 25º over a period of some 41,000 years. It is now about 23.5º

off the vertical axis.

We think of the orbit of the

Earth around the Sun as circular,

but in fact the Earth comes slightly

closer to the Sun at some times and

moves further away at others. The

orbit is not a circle but an ellipse.

Today, the earth comes closest in

January. 11,000 years ago, the clos-

est approach, the perihelion, took

place in July. This variation gives the

“precession of the equinoxes” and

takes place over a 21,000 year cycle.

In addition to the interplay of these two cycles, tilt and orbital ellipsis, an additional factor was

added by calculations made a century ago by the Serbian mathematician, Milutin Milankovitch. By

measuring the minute changes of the Earth relative to stars, he found that the Earth “wobbles” in its

orbit because the gravitational pull of the other planets and stars. (Astonishingly, he formulated his

theory while a prisoner of war in the First World War.)

GlaciersCh a p t e r 11


By measuring ice cores and observing effects on the ground, scientists can now date the major

swings of the Earth’s climate. For our purposes, it is sufficient to see only relatively recent changes.

Between 22,000 and 13,000 years ago, our ancestors – the few then alive – experienced what we call

“the Ice Age.” A forbidding and nearly impossible world it was. Much of the land was covered by vast

sheets of ice. This is what that meant in North America. Everything inside the blue-green line was

buried deep under ice.

Conditions in Europe were similar to those in America. Europe was very cold – with mid-summer

temperatures like winter temperatures on the northern coast of Siberia today. It was also bone dry.

As Jonathan Adams of the Oak Ridge National Laboratory has written, “Large ice sheets were pres-

ent over much of northern Europe, and ice caps covered the Alps and the Pyrenees [shown in white

on Professor Adam’s map below]. Forest and woodland [shown in green] were almost non-existent,

except for isolated pockets of woody vegetation in and close to the mountain ranges of southern Eu-

rope…” Open land was mostly steppe and tundra [reddish and gray] or desert [yellow] in southern Eu-

NOAA Paleoclimatology


rope. As is evident, most of Europe

was nearly uninhabitable. But, we

now know that bands of hunters

lived on the escarpment of what is

now the Mediterranean and hunted

in the protected and relatively warm

valley stretching south toward Sicily.

Unfortunately, except for occasional

“catches” of bone or stone tools by

fishermen, we cannot access informa-

tion on their lives because whatever

they left behind is now deep under

the modern sea.

About 15,000 years ago, ice sheets are estimated to have covered nearly a third of the land area

of the Earth – about 10 million square miles (26 million square kilometers) or an area the size of the

United States, Canada and China combined -- and in places it reached a thickness of 4 kilometers

(2.4 miles). With so much water stored in the glaciers, the level of the sea, according to David Archer

and Stefan Rahmstorf (The Climate Crisis) fell approximately 120 meters (almost 400 feet) lower than

today. One could have walked, as early hunters surely did, across many parts of what is today covered

by the sea. Dry land or “land bridges” linked Asia and North America, Malaysia and Indonesia, south-

ern France and Corsica, northern Europe and Scandinavia.

Obviously, most of the water that was locked up in ice 15,000 years ago has rejoined the sea, but

not all. According to the World Glacier Monitoring Service (WGMS), the 100,000 or so glaciers still

extant today cover nearly 16 million square kilometers (roughly 6 million square miles) — an area

about the size of Latin America — of which 13.5 million kilometers (5.25 million square miles) are

in Antarctica. While no ice sheets today are as massive as those in the Ice Age, substantial parts of the

Antarctic ice sheet are still 3 to 4 kilometers (1 to 1.5 miles) thick while part of the Greenland ice sheet

is up to 1,000 meters (3,280 feet) thick.

Now consider why we need glaciers. First, what they prevent. As Archer and Rahmtorf point

out. ““Greenland contains enough ice to raise the seas globally by 7 meters, and Antarctica 57 meters.

Thus, melting just a small fraction of this ice could raise the seas worldwide by several meters.” Were

this to happen, a study funded by the Pew Charitable Trusts predicted that “anticipated losses in agri-

culture and [flooding of ] real estate plus the cost of disease outbreaks and natural disasters associated

with rising sea levels…will exceed $7 trillion.” (Cited by Judith Schwartz in the April 3, 2010 Time) “This means,” said Eban Goodstein, the author of the Pew report, “that every working adult will have

to pay half of a year’s salary just to cover the damage of the breakdown of the Arctic air conditioner.”


Even a rise of 1 meter would endanger London, Cairo, Bangkok, Venice, Calcutta, Shanghai, New

Orleans and many other cities that together hold nearly half of the world’s population.

Second, what they contribute. Neither in Antarctica nor in Greenland do glaciers contribute to ag-

riculture or sustain dense populations, but in Europe, Latin America and Asia, they feed the rivers that

make large-scale, irrigated agriculture possible. For Europe, as Ray Smith pointed out (The Guardian,

July 23, 2011), “The Swiss Alps are often called ‘Europe’s water tower.’ Nearly 60 billion cubic meters

of water are stored in the Swiss glaciers. In Latin America, without them, life would be very difficult

in Colombia, Peru, Chile, Venezuela, Ecuador, Argentina and Bolivia. But it is Asia that would suffer

the most. Pakistan would wither and die without the yearly renewal by the glaciers of the Himalayas

of the Indus [see essay #13 on “The Intertwined Water Problems of India and Pakistan] and on an even

larger scale in Bengal, Bangladesh, and southeast Asia [see essay #14 Other Potential Conflicts over

Water] hundreds of millions of people would be at risk.”

In an attempt to dramatize the message of alarm to the public in other countries, the cabinet of

Nepal held a meeting at 5,200 meters (17,000 feet) on Mount Everest. Prime Minister Madhav Ku-

mar Nepal told the BBC’s Joanna Jolly (December 2, 2009) that snowfall is diminishing, glaciers are

melting and ‘a global treasure” is in danger of being destroyed. The mountains, he said, “are the water

towers of Asia.”

Not only the quantity of the water is crucial to the lives of about a quarter of the world population

but also the timing of release is important: glacial melt water comes just when farmers most need it – in

the summer growing season when there is less rain.

So crucial are glaciers to national economies that at least one has given rise to a war. Astonishingly,

fought at 20,000 feet (6,000 meters) and resulting in at least 3,000 casualties, India and Pakistan went

to war in 1984 over the Siachen glacier. India managed to seize control of the glacier and more than a

thousand square miles (3,000 square kilometers) of surrounding territory from Pakistan.

The importance of Siachen glacier is that its

melt water gives rise to one of the main tributaries

of the Indus river which in turn is the main source

of water for Pakistan. The glacier is enormous,

measuring 700 square kilometers (270 square

miles). And if its run-off were somehow diverted,

Pakistan would starve. So although it is located at

one of the most difficult places on Earth, where it

was believed until the 1970s that no one could live

more than a few days, it is strategic.Sketch map drawn from Wikipedia


Maintaining control of the glacier is a serious

drain on the Indian economy. The Indian Army

is building tunnels and air fields to supply a force

of roughly 20,000 men who now are in occupa-

tion of the mountain and the glacier. The picture

(right) of Indian army soldiers on patrol at almost

20,000 feet is drawn from an Indian publication

on the web, http://www.siachenglacier.com/

Thus, at least some governments have concluded that glaciers are among the most valuable of all

our natural inheritance. So are they diminishing? If so, why? And what can we expect in the near

future?

For so important a series of questions, it would be reasonable to think that governments all over the

world would be putting their best efforts and most highly trained scientists into finding answers. As-

tonishingly, this is not so. Despite the warning from a large majority of climate scientists who believe

that, as Justin Gillis reported (International Herald Tribune, November 13-14, 2010), there is a “risk

that the world’s land ice will go into an irreversible decline before this century is out…no scientifically

advanced country has made tracking and understanding the changes in the ice a strategic national pri-

ority.” The National Aeronautics and Space Administration (NASA) – as the reader will observe in the

numerous images in these pages – has made a major contribution, but the “ICESat” that was dedicated

to ice study came down in 2010 and no replacement is planned until at least 2015.

Regardless of the causes of the decline of glaciers, which those who deny global climate change dis-

pute, it would seem obvious that it would be worth knowing what is actually happening in an orderly

and timely fashion. The most accurate, most timely and often the only way to do this is with satel-

lite imagery. But, Gillis continued, “’We are slowly going blind in space,’ said Robert Bindschadlier

a polar researcher at the University of Maryland, Baltimore County, who spent 30 years with NASA,

studying ice.” This is why the lack of funding for observation deprives us of the factual information

which we need to set out judicious and relevant policies.

So what do we know from thousands of reports where investigators can reach the high and remote

areas where glaciers exist?

It is that almost everywhere Glaciers are in retreat.

In Switzerland, which has at least 1,500 glaciers of which the 30 most important have been moni-

tored on the ground from 1910, they are believed to have lost 50% of their former volume. (Quirin

Schiermeier, Nature 465) Projecting ahead, Professor Wilfried Haeberli remarked (quoted by Juliette


Jowit, The Guardian January 25, 2010) that while “we are on the path of the highest [melting] sce-

nario…[but even] if you take a medium scenario in the Alps about 70% will be gone by the middle

of the century…”

In the Andes, the speed of melt has astonished observers. As John Vidal reported several years ago

(The Guardian, August 29, 2006) ”According to the Colombian Institute of Hydrology, back in 1983,

the five major glaciers in El Cocuy national park were expected to last at least 300 years, but measure-

ments taken last year suggest that they may all disappear within 25 years.”

While American farmers and city dwellers are not so dependent on glaciers as Latin Americans,

Europeans and Asians, the decline of the American glaciers is also dramatic. As Professor Lonnie

Thompson remarked (“Climate Change: The Evidence and Our Options,”) “Glacier National Park in

Montana contained more than 100 glaciers when it was established in 1910. Today, just 26 remain,

and at the current rate of decrease it is estimated that by 2030 there will be no glaciers in Glacier

National Park.”

Melting of glaciers can be recorded by dated photographs. Here are two juxtaposed by the

National Snow and Ice Data Center at the University of Colorado:

Muir Glacier, photographed by William O. Field on 13 August 1941 (left) and by Bruce F. Molnia on 31 August 2004 (right)

Pedersen Glacier 1917 same view 2005


After studying 9 mountain ranges on 4 continents, The World Glacier Monitoring Service

(WGMS) issued a report on January 25, 2010 predicting that many glaciers, particularly in the lower

ranges like the Alps and the Pyrenees and parts of the Andes and the Rockies in the US, will disappear

before the middle of this century.

But it is in Asia that paradoxically we know least about glaciers while more people than anywhere

else depend upon them. The Himalayas in Tibet and Nepal have been called the “third pole” because,

after the Arctic and the Antarctic, their more than 46,000 glaciers and vast stretches of permafrost

contain the Earth’s largest store of frozen fresh water. It is on them and the rivers to which they give

rise, as Jane Qiu pointed out (Nature, 468, November 10, 2010) that about 1.5 billion people depend.

There is no glacier inventory for the entire area, but a Chinese team led by Liu Shiyin of the Chinese

Academy of Sciences’ “Cold and Arid Regions Environmental and Engineering Research Institute” in

Lanzhou has documented some 24,300 glaciers; the study shows that over the last 30 years, “the total

surface area of glaciers has decreased by 17% and that many have disappeared since the last inven-

tory began...’the impact of climate change on some Himalayan glaciers is much worse than previously

thought,’ says Tian Lide, a glaciologist at the ITP [Institute of Tibetan Plateau Research in Beijing].”

One of the dangers of glacier melting is that substantial amounts of run-off water can form in

pools that are temporarily blocked by ice. Then, as water builds up and ice melts, the accumulated

water can rush down a valley and wash away villages or towns, killing farmers and their animals. Here

is a scene of such pools in Bhutan.

As the NASA analyzer commented, “As glaciers grind their way across the landscape, they pile up

rocky debris, forming moraines. At the terminus of a glacier, moraines can act as natural dams for lakes

filled with melt water. When they fail, they can create catastrophic glacial outburst floods. On October

7, 1994, in the Bhutan Himalaya, a partial collapse of a moraine along the edge of the Luggye Lake

released a glacial outburst flood that killed 21 people and swept away livestock, crops, and homes.”

NASA satellite image October 28, 2009


This image from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiom-

eter) instrument aboard NASA’s Terra satellite shows the formation of lakes as a result of the run-off of

melt-water. The scene on the left is from 1994 when the valley in the center was still ice and snow; the

scene on the right five years later shows that the ice and snow have melted, forming a lake, with a small

outlet that blocked but potentially will collapse, allowing a deluge to roar down the valley.

So the question arises, what has caused the recent and rapid melting of the glaciers? In the Tibet,

the environmental scientist Xu Baiqing from the ITP dug into glaciers, extracting cores of ice that

showed heightened levels of soot (black carbon) dating from the 1990s and coincided with industrial

growth in the area. A similar study with similar results was carried out in Nepal by Anbgela Mariinoni

of the Italian Institute of Atmospheric Sciences and Climate. Soot diminishes the ability of the glaciers

to reflect sunlight (the so-called “albedo effect”) and so, the Italian scientists concluded, could speed

up melting by as much as 34%.

Many scientists, some probably reacting to the virulent campaigns swirling around the issue of

climate change, are cautious about the issue of cause. Professor Robert Bindschadlier, a polar re-

searcher at the University of Maryland, said (International Herald Tribune, November 13-14, 2010)

that “Strictly speaking, scientists have not proved that human-induced global warming is the cause of

the changes.” Matthias Huss, a glaciologist at the University of Fribourg hit a middle course, saying

(Nature 465, June 4, 2010) “current glacier retreat might be equally due to natural climate variations as

it is to anthropogenic greenhouse warming.” But Professor Lonnie Thompson, the renowned climate

specialist at Ohio State University, was more blunt (“Climate Change”): “it is clear that mountain gla-

ciers and polar ice sheets are melting, and there is no plausible explanation for this but global warming.

Add to this the laboratory evidence and the meteorological measures, and the case for global warming

cannot be denied.”

As we know from press reports, many do still deny it. But arguments over the causes are trivial;

whether they are man-made or natural, the effects are observable and frightening; the rational and


prudent thing to do is to stop debating about the causes and focus on what needs to be done to slow

down, mitigate and prepare for the probable or at least possible consequences. Climate scientists,

wrote Justin Gillis (International Herald Tribune November 13-14, 2010) “worry that the way things

are going, extensive melting of land ice might become inevitable before political leaders find a way to

limit the gasses [that presumably cause the climate change], and before scientists even realize such a

point of no return as been passed.”

It is striking, as Suzanne Goldenberg reported (The Guardian, September 24, 2011) that moun-

tain climbers report that even above 8,000 meters (20,000 feet) Mount Everest is losing its ice cover.

“When I climbed Mount Everest last year,” said John All, an expert on Nepal glaciers from the Univer-

sity of Western Kentucky, “I climbed the majority of ice without crampons because there was so much

bare rock. In the past that would have been suicide because there was so much ice.” And the famous

guide Tshering Tenzing Sherpa commented, “Everything is changing with the glaciers.” That is what

the Nepal government was trying to dramatize by holding a cabinet meeting high up on the mountain.

So what do governments and their scientific advisers think can now be done about the potential

release of huge volumes of icy water into the sea? The Netherlands, long accustomed to the danger of

the sea, is already planning to build huge new dykes to protect the land from rising and surging seas.

Venice is in the midst of a tremendously expensive and highly complex program of protection from

surges. Most countries cannot afford such measures. Bangladesh cannot possibly cope with the danger

of a rising sea. And some of the tiny island republics of the Indian and Pacific oceans have begun the

process of evacuation. Even the rich countries will be hard pressed – as was shown by the flooding of

New Orleans – to save all the coastal cities. The costs will be beyond calculation.

The other course of action is, of course, to cut back on the causes of global warming (on which see

the essay on Climate, #1 in this series.) There are calculations on the cost of such a policy and it is

surprisingly relatively inexpensive. Lord Stern (The Economics of Climate Change) estimated that “if we

don’t act, the overall costs and risks of climate change will be equivalent to losing at least 5% of global

GDP [gross domestic product] each year, now and forever…In contrast, the costs of action – reducing

greenhouse gas emissions to avoid the worst impacts of climate change – can be limited to around 1%

of GDP each year.”

Also by comparison, this amounts to about one third of most countries expenditure on the military

quest for security. But, most specialists believe, the longer we delay, the higher will rise the costs.

glaciers

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