Morphological classification

Glacier form is a function of climate and topography, and therefore a variety of glacier morphologies exists, from the smallest niche glacier to the largest ice sheet. A first-order classification into ice sheets and ice caps unconstrained by topography can be subdivided into a second-order classification of ice domes, ice streams and outlet glaciers. Glaciers constrained or controlled by topography include icefields, valley glaciers, transection glaciers, cirque glaciers, piedmont lobes, niche glaciers, glacierets, ice aprons and ice fringes. Marine glaciers include ice rises, glacier ice shelves and sea-ice ice shelves (Ommanney, 1969;

Table 4.1 Distribution of glacierized areas of the world (adapted from World Glacier Monitoring Service)

Continent

Region

Area (km1)

Totals

South America

Terra del Fuego'Patagonia

21,200

Argentina north of 47.5"S

1385

Chile north of 46 S

743

Bolivia

566

Peru

1780

Equador

120

Colombia

1 1 1

Venezuela

3

25,908

North America

Mexico

11

USA and Alaska

75,283

Canada

200.806

Greenland

1,726.400

2,002,500

Africa

10

Europe

Iceland

II.260

Svalbard

36.612

Scandinavia and jan Ma/en

3174

Alps

2909

P/renees'Mediterranean mountains

12

53,967

Asia and Russia

Commonwealth of Ind. States

77,223

Türke/, Iran and Afghanistan

4000

Pakistan and India

40,000

Nepal and Bhutan

7500

China

56.481

Indonesia

7

185,21 1

Australasia

New Zealand

860

860

Antarctica

Subantarctic islands

7000

Antarctic continent

13,586.310

13.593,310

Armstrong et al, 1973; 0strem, 1974; Sugden and John, 1976; Benn and Evans, 1998).

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