Glaciers Glaciers occupy 11% of the land. During the era of maximum glaciation, they covered 30% of the land. Modern glaciers contain 70% of all fresh water reserves on Earth. Volume The volume of water contained in all glaciers corresponds to the amount of atmospheric precipitation falling on Earth for almost 50 years, or the flow of all rivers on Earth for 100 years. Glacier Information
If the ice melted, the sea level would rise by 64 meters. If the ice melted, the sea level would rise by 64 meters. Vast areas would be flooded: thousands of cities and villages would be under water. Vast areas would be flooded: thousands of cities and villages would be under water.
For a glacier to form, it is necessary that more snow falls than can melt. so that the air temperature is lower
TEST (Find the correct answer: draw an arrow from the question to the answer) 1. Glaciers formed where the earth's surface is above the snow line. 2. Accumulation of fresh ice on land. 3. The limit above which snow can accumulate and does not melt. 4. Glaciers formed in the mountains. 5. Fragments of rocks brought by a glacier A. Snow line B. Cover glaciers C. Glacier D. Moraine D. Mountain glaciers Answer options:
Test yourself 1. Glaciers are formed where the earth's surface is above the snow line. 2. Accumulation of fresh ice on land. 3. The limit above which snow can accumulate and does not melt. 4. Glaciers formed in the mountains. 5. Rock fragments brought by the glacier B. Cover glaciers B. Glacier A. Snow line D. Mountain glaciers G. Morena G. Morena
Glaciers Geography lesson in 6th grade
Do you want to know...
What is a glacier?
How are glaciers formed?
Distribution of glaciers
What types of glaciers are there?
Properties of glaciers
The importance of glaciers
What is a glacier?
A glacier is a long-term accumulation of fresh ice on land.
Unlike the ice that covers our rivers and lakes in winter, glacial ice is formed not from water, but from snow.
How are glaciers formed?
Clue
How are glaciers formed?
At what temperature does water freeze and not melt?
Can glaciers form in our area?
In those areas of the Earth where temperatures are low all year round, the snow that falls does not melt, but accumulates. Melt water seeps into it and freezes again. Over a long period of time, the snow compacts and turns into granular firn riddled with pores. In the process of further compaction and recrystallization, firn becomes real ice.
Clue
Can a glacier form on Mount Kilimanjaro in Africa if the temperature at the base is +25 degrees all year round? (With altitude, the temperature decreases by 6 degrees every 1000m?
Glacier - (German glacier), an icy river descending through valleys or from high mountains, or in polar countries. The glacier serves as one of the forms of unloading the huge supply of snow and firn, which falls in significant quantities above the snow line of the mountains. For the formation of glaciers in mountains or in polar countries, the presence of basins among the mountains is necessary.
Where on Earth are there areas with constantly low temperatures and precipitation in the form of snow?
How are glaciers shown on the map? Find areas covered with glaciers and write them down in your notebook.
What are glaciers?
What two groups can the glaciers you discovered be divided into?
mountain glacier
Cover glacier
The structure of a mountain glacier
glacier feeding
Snow border
Glacier tongue
Think about it?!
- Will the snow line be at the same height in the north of the Ural Mountains and the Caucasus Mountains?
In the north of the Ural Mountains, the snow line will be much lower - at an altitude of 1500 m, since this territory is located beyond the Arctic Circle.
Elbrus - the main peak of the Caucasus
Polar Urals
Kilimanjaro translated means “shining mountain.” Its top is covered with a glacier. The snow line is at an altitude of 4500 meters, since only at this altitude is t below 0.
Movement is one of the properties of a glacier
There is a positive temperature under the glacier, the ice is melting and the top layer of soil is moistened. The glacier slides along it like clockwork under the weight of its gravity. In the mountains it rushes down, and cover glaciers from the center to the periphery, leveling the terrain along its path. In front of it, the mountain glacier moves rocks, forming lateral moraines. Having reached the snow line, the glacier begins to melt, forming a terminal moraine. The edges of ice caps break off and form icebergs.
Types of Icebergs
Iceberg - ice mountain
pyramidal iceberg
table iceberg
Alexey Pavlovich Fedchenko
A.P. Fedchenko was the first Russian traveler to visit the Alai Valley, discover the Trans-Alai Range and its highest peak - Lenin Peak. The results of expeditions to Central Asia were not limited only to the geographical discoveries of new mountain ranges and peaks. Fedchenko collected a wealth of materials on the study of flora and fauna and made a number of observations that speak of his brilliant abilities as a research scientist.
What is a lake called? What are the signs of a lake? What is the difference between a lake and a river or sea? How do lakes differ based on the origin of their basins? Why are drainage lakes, as a rule, fresh, and drainless lakes salty? Is it possible to distinguish fresh lakes from salt lakes using a map? Can a lake be larger than the sea? Give an example. Can a lake be deeper than the sea? Give an example. From the listed objects, select lakes: Caspian, Nile, Baikal, Himalayas, Ladoga, Baltic, Mediterranean, Titicaca, Chad. 2
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Problem 5895: 1000*6= 35.3 0 C – temperature change 25 0 C-35 0 C-10 0 C => means there is a glacier Snow line at altitude: 10/6=1.7*1000=1700 m = 4195 m 10 that means there is a glacier Snow line at an altitude: 10/6=1.7*1000=1700 m 5895-1700= 4195 m 10"> that means there is a glacier Snow line at a height: 10/6=1.7*1000=1700 m 5895 -1700= 4195 m 10"> means there is a glacier Snow boundary at height: 10/6=1.7*1000=1700 m 5895-1700= 4195 m 10" title="Task 5895:1000*6= 35.3 0 C - temperature change 25 0 C-35 0 C-10 0 C => means there is a glacier Snow line at altitude: 10/6 = 1.7 * 1000 = 1700 m 5895-1700 = 4195 m 10"> title="Problem 5895: 1000*6= 35.3 0 C – temperature change 25 0 C-35 0 C-10 0 C => means there is a glacier Snow line at altitude: 10/6=1.7*1000=1700 m 5895- 1700= 4195 m 10"> !}
Cover glaciers Form in the polar regions 98.5% of the area of glaciers on Earth is occupied by glaciers of this type Thickness: from 100 m to 2000 m in Greenland, from 2000 to 4000 m in Antarctica Thickness: from 100 m to 2000 m in Greenland , from 2000 to 4000 m. - in Antarctica 13
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Glaciers Kochkin Alexey 2013
Glacier structure
The Fedchenko Glacier in Tajikistan is the longest glacier outside the polar zones. It is located at an altitude of 6000 meters above sea level. In addition, it is the largest glacier in the Pamir Mountains and among all Asian continents. The glacier is so huge that the size of its “tributaries” far exceeds the most powerful European glaciers.
Malaspina, USA The glacier covers an area of 4275 square kilometers, located at the foot of Mount St. Elias in Alaska.
The red-brown water that flows from the glacier has a temperature of -7ºC, 2.5 times saltier than ocean water, there is almost no oxygen in it, but bacteria have been found “sealed” under the ice cover and “breathing” iron and sulfur compounds. The size of the reservoir is unknown, it is assumed that it is under 400-meter thick ice and stretches for a distance of up to 4 kilometers, its age is about 2 million years. The glacier is a “capsule” inside which microorganisms have survived without oxygen, light and heat.
Vatnaekul glacier in Iceland, the largest glacier in Europe
Pasterze Glacier Pasterze (German: Pasterze) is the largest glacier in Austria. The length is about 9 km, located at an altitude of 3463 to 2100 m above sea level. Pasterze Glacier in 1900
Mushketov Glacier The Mushketov Glacier is a valley tree-like glacier in the Central Tien Shan in Kyrgyzstan, located on the northern slope of the Saryjaz ridge, at the headwaters of the Adyrtor River, a left tributary of the Saryjaz River. The length of the glacier is 20.5 km, width - from 1 to 1.8 km. Area - 68.7 km². The feeding area lies in a huge cirque at an altitude of 4500-5500 m, the firn line is at an altitude of 4100 m. The tongue of the glacier ends at an altitude of 3440 m. The lower part of the glacier is covered with moraine for 5 km. In 1957, a sharp movement of the glacier occurred: its tongue moved down the valley to a distance of 4.5 km. The glacier is currently retreating. The glacier was named after the outstanding Russian explorer Ivan Vasilyevich Mushketov.
Ice shelf The Shackleton Ice Shelf is an ice shelf in East Antarctica, on the coast of Queen Mary Land and Wilkes Land, located between 95° and 105° east longitude. ice shelf
Hubbard Glacier 67 km of the glacier are in the mountains of Canada, and the lower 48 km are in the United States. In one year, the glacier covers approximately 17-18 meters. It took the glacier 400 years to descend from Mount Logan to the ocean, which is exactly the age of the ice at the foot of Hubbard. The width of the glacier varies depending on the time of year - 9 km in summer and 15 km in winter. The height of the frontal part of the glacier above sea level reaches 120 meters, and the average height of the firn line is 850 meters.
Hubbard Glacier
Austfonna, Norway This glacier is located on the Spitsbergen archipelago, and ranks first in size on the entire Old Continent. Its area is 8200 square kilometers.
Aletsch, Switzerland The largest Alpine glacier is located in Switzerland, on the Valais. The total area of this glacier is 117.6 square kilometers, and its length is more than 20 km. The Aletsch Glacier, as well as the nearby Jungfrau Mountains, have been declared a UNESCO World Heritage Site.
Schneeferner, Germany In the region of the Bavarian Alps there is the largest glacier in Germany, which is also the northernmost Alpine glacier. It is located in the Zugspitze massif (the highest mountain in the country), on the Zugspitzplatt plateau and its area covers about 3 hectares.
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“...The appearance of monstrous ice sheets
meant the destruction of all organic life
on the ground. The territory of Europe, which is before
covered with tropical vegetation and
inhabited by elephants and hippos, suddenly
disappeared under endless masses of ice,
flooded everything - plains, lakes, seas,
hills..."
Ice, huge masses of ice that hid underneath
ourselves, the continents - this is the image of the glacial
period, the image of the nature of his cold world,
created by Jean Louis Agassiz, an outstanding
Swiss scientist of the 19th century, founder
glacial theory, or the doctrine of the ancients
glaciations.
WHAT IS A GLACIER?
Glacier is...natural accumulations
snow and ice, having
ability to move
moving ice accumulation
atmospheric origin on
land surface
Glacier formation
Glaciers are formed as a result of the accumulation andsubsequent conversion of atmospheric solids
precipitation (snow) with a positive long-term balance.
The general condition for the formation of glaciers is a combination
low air temperatures with large amounts of solids
precipitation, which occurs in cold countries
high latitudes and mountain tops. However, the more
the amount of precipitation, the higher the air temperature may be.
Thus, the annual amounts of solid precipitation vary from 30-50 mm per
Central Antarctica up to 4500 mm on the glaciers of Patagonia,
and the average summer temperature is from – 40 C in Central
Antarctica up to 15 C at the ends of the longest glaciers
Central Asia, Scandinavia, New Zealand, Patagonia.
The process of glacier formation is the process of turning snow into ice.
Snowflakes turn into grains underinfluence of evaporation, melting and
pressure of overlying layers.
Grainy ice - firn - is formed.
Firn is formed in the mountains above the snow
lines and in the polar regions, where
the fallen snow does not have time to melt over the summer.
Perito Moreno Glacier in Patagonia (southern Argentina)
https://www.youtube.com/watch?v=ANXUIzBCWv8Glaciers have different origins:
IntegumentaryMountain
Mountain covers MOUNTAIN GLACIERS
Formed where mountains reach
climatic snow limit,
located at a certain height in
atmosphere.
Mountain glaciers are divided into:
MountainProne
Dolinnye
Glacier in Glacier National Park VALLEY GLACIER
Cover glaciers are divided into:
Ice domes (large convexglaciers up to 1000m thick);
Ice sheets (convex glaciers
with a thickness of more than 1000 m and an area
over 50 thousand km.kv)
Outlet glaciers, ice sheets,
ice shelves.
Ice sheet glaciers
Contains most of the reserves freshwater on Earth. One medium iceberg
sizes consists of the same number
fresh water, which is carried out in a year
small river.
Ice sheet glaciers
COVER GLACIERS are located oncontinents or large islands, in those
areas where the climate is snowy
the border is located at ocean level. TO
These include the glaciers of Antarctica,
Greenland, Arctic islands.
Descending to the sea, the glacier forms an ice shelf located on the continental shelf shelf. The part that breaks off is called an iceberg
Iceberg Ice Shelf
Mountain cover glaciers are divided into:
Glaciers of the foothillsGlaciers
Reticulated foothills
glaciation is formed in that
case if the climatic snow
the border is very low and
the amount of precipitation is high.
Glaciers formed in the mountains quickly
come out
Reticulate
glaciation
typical for
plain. Distributed
Iceland, Spitsbergen.
Alaska.
Glaciers of Spitsbergen
Hubbard Glacier (Alaska)
Glacier feeding
The main source of food for glaciers isprecipitation. To other sources
nutrition includes continental transport -
snow, transported, avalanche snow,
sublimation on the ice surface.
Glacier movement
Glaciers move along the slope of the terrain,movement is influenced by force
gravity.
To increase the speed of movement
is influenced by an increase in ice mass and
his temperature. In addition to such forced oscillations,
directly related to mass balance,
some glaciers are experiencing movement (
pulsations), which arise as
the result of processes within itself
glacier - spasmodic changes
conditions on the bed and redistribution
substances between areas of accumulation and
ablation (melting) without significant
changes in the total mass of ice. Glacial waters are sources
food for rivers Complete melting of glaciers
would lead to a rise in sea levels by
60 m and flooding of 10% of the land.