give a detailed account of the features formed by wind waves and ice
Answers
Answer: the features of wind waves and ice are Wherever the rate of snow melting or its
evapouration is lower than the rate of snowfall in a year, snow accumulates into
great mass of ice. Permanently snow covered regions of this type are called snow
- fields. Snow - fields occur in polar regions and on high mountainous areas.
Snowfields are always found above the snow line. Snow line is an imaginary line
above which there is permanent snow. The height of the snow - line is not uniform
and is affected by latitude, amount of snowfall, direction of winds and slope Types of Glaciers
On the basis of their location or area of origin, glaciers are divided into two types:
(i) continental glaciers and (ii) valley glaciers.
(i) Continental Glaciers
A thick ice sheet covering vast area of land is called a continental glacier. The
thickness of ice in such regions goes upto thousands of metres. Glaciers of this
type build up at the centre and move outward in all directions. Continental glaciers
of today are found mainly in Antarctica and Greenland. The precipitation in these
regions occurs in the form of snow. It gets accumulated year by year because of
relatively slower rate of its melting.
(ii) Valley Glaciers
When a mass of ice from the high mountainous regions starts moving down into
the pre-existing valleys, it is called a valley glacier or a mountain glacier. The shape
of the valley glaciers depends on the valley it occupies. Where the valley is broad,
the glacier spreads outwards and where the valley is narrow, the glacier contracts.
The longest glacier in India is the Siachen Glacier in Karakoram range which is 72
kilometres long. Gangotri Glacier in Uttarakhand is 25.5 kilometres long. There
are many smaller glaciers in other parts of the Himalaya. Their length varies from 5
103
Notes
GEOGRAPHY
The Work of Moving Ice, Wind and Sea Waves MODULE - 2
Explanation: