Glaciers are large, thick masses of ice formed from compacted snow that accumulates over many years. Glaciers form in areas where snow accumulation exceeds melting. Due to their great mass, glaciers slowly flow downhill like rivers. Glaciers erode the underlying landscape and form characteristic landforms as they advance and retreat. Melting glaciers provide fresh water for many communities but are now threatened by global warming.

2. What are glaciers?
Glaciers are made up of
fallen snow that, over
many years, compresses
into large, thickened ice
masses. Glaciers form
when snow remains in one
location long enough to
transform into ice. What
makes glaciers unique is
their ability to move. Due
to sheer mass, glaciers
flow like very slow rivers.
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3. Glacier formation
• Form where snow and ice accumulation exceed
snow and ice melt
• Under the pressure of the layers of ice and snow
above it, this granular ice fuses into denser and
denser firn
• Firn is partially-compacted neve.
• Neve is a young, granular type of snow which
has been partially melted, refrozen and
compacted.

4. Glacier formation
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5. Growth of glaciers
 Glaciers grow or recede as a function of the balance
between accumulation and ablation of snow and ice.
 The accumulation zone is a region where snowpack or
superimposed ice accumulation persists.
 The ablation zone is the region where all of the snow
has melted away and bare glacier ice is exposed. 5

6. Crevasses in glaciers
 Crevasses are common in the upper parts of
glaciers when the ice is subjected to
tension.
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7. Structure of glaciers
• The region near the head of the glacier where snow is
converted to firn and then ice is called the zone of
accumulation.
• The region near the foot of the glacier is called the zone
of ablation; this is where ice is lost by melting,
evaporation or calving (to make icebergs).
• Separating the accumulation zone from the ablation zone
is the equilibrium line. The equilibrium line is located at
the equilibrium line altitude (ELA).
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9. Glacial erosion
• Abrasion: grinding of surface.
• Glacial flour: silty powder that develops as
glaciers ground down rocks and pebbles under
them.
• Glacial striations: grooves and striations caused
by rock fragments.
• Plucking: water freezes and cracks rocks, and
these rock fragments and carried by the glacial
ice.
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11. Glacial landforms
The landforms created by glacial erosion are:
• Cirques:
• Arêtes
• Pater noster lakes
• U Shaped Valleys or glacial troughs
• Tarn
• Hanging Valleys
• Horn
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13. Depositional features
• Moraine: features made of till
• Lateral moraine: till collected on valley sides by rock falls
and plucking off valley walls;
• Medial moraine: formed by merging of lateral moraines as
two glaciers meet;
• Outwash plain: region in front of a melting glacier; typically
has braided streams
• Terminal moraine: deposited at the furthest point of
glacial advance
• Till: unsorted sediment deposited directly by glaciers
• Ground moraine: "blanket'' of till left by melting glacier
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15. Where are they located?
• Presently, glaciers occupy about 10 percent of
the world's total land area, with most located in
polar regions like Antarctica, Greenland, and the
Canadian Arctic.
• Glaciers are found on nearly every continent,
even Africa.
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16. Distribution of Glaciers in the
world
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17. There are primary two types
of glaciers
Alpine glaciers
Cirque glaciers
 Valley glaciers
 Ice caps
Piedmont glaciers
 Tidewater glaciers
Continental ice sheet glaciers
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18. Alpine glaciers
• Glaciers in mountains that flow down valleys is
called alpine glaciers.
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19. Piedmont glacier
• When two or glaciers meet and merge at the
base of mountains, the new glacier is called a
piedmont glacier.
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20. Tidewater glacier
• If the piedmont glacier flows to the sea, it's
called a tidewater glacier.
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21. Cirque glacier
• Glacier confined by a valley; forms in a cirque
(semicircular basin at head of valley formed by
plucking of bedrock by glacier moving down hill)
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22. Valley glacier
• Valley Glacier confined to a valley usually
formed from streams.
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23. Ice caps
• An ice cap is an ice mass that covers less than
50,000 km² of land area (usually covering a
highland area). Larger ice masses covering more
than 50,000 km² are termed ice sheets.
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24. Continental ice sheet
• Continental ice sheet largest of glaciers
that cover thousands of square kilometers
found only in Greenland and Antarctica.
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25. How does it affect life on earth?
• Glacier melting water provides many regions
with fresh drinking water.
• They create homes, ecosystems, and habitats for
many organism in our animal kingdom.
• The melt water AKA rundown of Glacier water
provides energy resources to certain countries.
• They provide water to dessert regions.
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26. How does it affect life on earth?
• Glaciers are also a natural resource, and people
all over the world use the melted water that
glaciers produce.
• People living in arid climates near mountains
often rely on glacial melt for their water for part
of the year.
• Farmers have also irrigated their crops for
hundreds of years by channeling melted water
from glaciers to their fields.
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27. Glaciers are being threatened
everyday!
The biggest threat to Glaciers is Global Warming.
- Global warming is melting our Glaciers creating sea levels
to rise dramatically
- Melting Glaciers also means that the habitants will lose
their home and way of life creating tragedy in
ecosystems across the world.
- Many regions will lose their fresh water source
- Many regions near the oceans and seas will become
flooded and non-existent.
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28. What are some solutions?
• Find energy resources that do not produce greenhouse
gases.
• Contribute to the cause of eliminating green house gases
by monitoring your personal carbon footprint
• Corporations need and should adopt environmental
ethics and promote and implement better measures to
reduce greenhouse gases
• People should look into alternate energy resources that
do emit green house gases into the atmosphere such has
solar and turbine energy.
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