THE HIMALAYAS

THE GREAT WALL OF A INDIA

HISTORY OF HIMALAYATHE BIRTH OF HIMALAYAThe birth of Himalayas dates back to million of years ago. There were series of stages, which led to the formation of the Himalayas. The formation of the Himalayas is the result of a collision of India with Asia along the convergent boundary. There were powerful earth movement between the Indo-Australian Plate and the Eurasian Plate that resulted in the creation of the Himalayan range. The earth movements raised the deposits, which were laid down in the shallow Tethys Sea, which is on the present location of the mountains. Today also there is constant change and development in the mountains due to earthquakes and tremors. The formation of the Andaman and Nicobar Islands in the Bay of Bengal and the Arakan Yoma highlands in Myanmar is the result of this collision. The collision of India with Asia was due the mechanics beneath the earth's surface. There are various plates that collide, recede and slide from each other at about 2 cm/year. This action beneath the earth's surface leads to the rising of the Himalayas by about 5 mm per year. The heat generated beneath the earth's surface results in this action of collision. It is the process of convection that drives hot current upwards due to less density and cold current downwards due to more density. This movement of Indian plate into the Asian plate makes this region very active and prone to earthquakes. In the future also the plate will move like this causing changes in the structure of the Himalayas. The height and width of the mountain will change according to the action beneath the earth's surface. In the north the mountains will be taller and smaller in the south while the width remains the same.

REGIONAL DIVISION OF HIMALAYA

1. HIMADRI• This is the northernmost

range and is also known as 'Himadri'.

• This is the most continuous range

• It contains the loftiest peaks.

• The folds of the Great Himalayas are irregular in nature

• Famous glaciers like the Siachen Glacier, the Gangotri and Yamunotri, etc

REGIONAL DIVISION OF HIMALAYA

2. HIMACHAL• This range lies towards the

south of the Great Himalayas• The altitude of peaks in this

range varies from 3,700 to 4,500 meter

• Average width of this range is 50 km.

• This range is mainly composed of highly compressed and altered rocks.

• This region is also known as for its hill stations (for e.g. Kullu,-Manali, Kufri, Shimla, Mussoorie, Nanital, etc.).

REGIONAL DIVISION OF HIMALAYA

3. THE SHIWALIKS• The outermost range of the

Himalayas is known as Shiwaliks, also known as Manak Parbat in ancient times.

• The altitude varies between 900 and 1100 meters in this range.

• The width varies between 10 to 50 km.

• These ranges are composed of unconsolidated sediments brought down by the rivers.

• The longitudinal valleys lying between the Himachal and Shiwaliks are called 'Dun'.

HIMALAYAN REGIONS FROM WEST TO EAST:

• Punjab Himalayas: This part lies between the Indus and Sutlej. They are also known as Kashmir Himalaya and Himachal Himalaya.

• Kumaon Himalayas: This part lies between Sutlej and Kali rivers.

• Nepal Himalayas: This part lies between the Kali and Tista rivers.

• Assam Himalayas: This part lies between the Tista and Dihang rivers.

TOP VIEW OF MAJESTIC MOUNTAINS:-HIMALAYA’S

WHY HIMALAYAS ARE IMPORTANT TO US?

CLIMATE INFLUENCE

• The Himalayas play a very significant role in influencing the climate of India. By virtue of their high altitude, length and direction, they effectively intercept the summer monsoons coming from the Bay of Bengal and Arabian Sea and cause precipitation in the form of rain or snow.

• Besides, they prevent the cold continental air masses of central Asia from entering into India. Had there been no Himalayas, the whole of India would have been a desert in the absence of precipitation and its winters would have been very severe under the influence of cold airmasses coming from Central Asia. According to the latest meteorological studies, the Himalayas are responsible for splitting the jet stream into two branches and these in turn play an extremely important role in bring monsoons in India.

DEFENCE• The Himalayas have been protecting India from outside

invaders since the early times thus serving as a defence barrier. But the Chinese aggression on India in October,

1962 has reduced the defence significance of the Himalayas to a considerable extent. In spite of

advancement in modem warfare technology, the defence significance of the Himalayas cannot be ignored

altogether.

SOURCE OF RIVERS

• Almost all the great rivers of India have their sources in the Himalayan ranges. Abundant rainfall and vast snow-fields as well as large glaciers are the feeding grounds of the mighty

rivers of India. Snow melt in summer provides water to these rivers even during dry season and these are perennial rivers. The Himalayan Rivers, along with hundreds of their tributaries, form the very basis of life in the whole of north

India.

FLORA & FAUNA• FLORA

• The transition zones from sub-tropical warmth to arctic colds are telescoped into a mere 250 kilometers (156 miles) between the Punjab plains and the Tibetan plateau

• Towards the plains, the Shivalk are fringed with broad-leaved Sal and silk cotton, which give way to sheesham, kail and the long leaved cheer pine on the slopes of the foothills. A temperate zone of the mixed forests follows on the lower reaches of the Dhauladhars and Pir Panjal ranges,

• FAUNA• the Himalayan choughs, rose

finches and accentors. Overhead, gliding in the thermals, one is likely to spot the griffon vulture, perhaps the Lammergeyer with its beard and nine-foot wingspan, and if one is lucky, the golden eagle. The sight of a skein of wild geese on their migratory flight, flights the wind at 6,000 meters (20,000 feet)

WHAT PRONES WE HAD GOT FROM HIMALAYAS? AND HOW WE CAN

RESOLVE THEM NATURAL?

KEDARNATH DISTRUCTION• In June 2013, a multi-day cloudburst centered on

the North Indian state of Uttarakhand caused devastating floods and landslides becoming the country's worst natural disaster since the 2004 tsunami.

• REASON BEHIND THE DISTRUCTION• The reason the floods were on such a larger scale

than the regular floods the state usually received was because of the debris of the building of dams upstream. The debris blocked up the rivers, causing major overflow.

• The India Meteorological Department (IMD) linked heavy to very heavy rain-fall on the higher Uttarakhand, Himachal and Nepal Himalaya to the convergence of the Southwest Monsoon trough and (5:00 p.m.) and 16 June (5:00a.m.) 2013.

DESSERTSA DEAD AREA OF A NATIONAL

WHAT ARE DESSERTS ? • A desert is a barren

area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation.

LARGEST AND SMALLEST DESERTS:-

LARGEST DESERT• The largest is the Sahara

Desert , a subtropical desert in northern Africa. It covers a surface area of about 3.5 million square miles.

SMALLEST DESERT• The Carcross Desert,

tucked away in the Yukon Territories, measures approximately 1 square mile. it's often referred to as the smallest desert in the world, but technically, it's just a series of sand dunes since the area is too humid to be considered an actual desert.

TYPES OF DESERTS• TRADE WIND

DESERTS• The trade winds in two belts on

the equatorial sides of the Horse Latitudes heat up as they move toward the Equator. These dry winds dissipate cloud cover, allowing more sunlight to heat the land. Most of the major deserts of the world lie in areas crossed by the trade winds. The world's largest desert, the Sahara of North Africa, which has experienced temperatures as high as 57° C, is a trade wind desert.

TYPES OF DESERTS• MIDLATITUDE DESERT • Midlatitude deserts occur

between 30° and 50° N. and S., poleward of the subtropical highpressure zones. These deserts are in interior drainage basins far from oceans and have a wide range of annual temperatures. The Sonoran Desert of southwestern North America is a typical midlatitude desert.

TYPES OF DESERTS• RAINSHADOW

DESERT• Rain shadow deserts are

formed because tall mountain ranges prevent moisture-rich clouds from reaching areas on the lee, or protected side, of the range. As air rises over the mountain, water is precipitated and the air loses its moisture content. A desert is formed in the leeside "shadow" of the range.

TYPES OF DESERTS• COASTAL DESERT• Coastal deserts generally are found on

the western edges of continents near the Tropics of Cancer and Capricorn. They are affected by cold ocean currents that parallel the coast. Because local wind systems dominate the trade winds, these deserts are less stable than other deserts. Winter fogs, produced by upwelling cold currents, frequently blanket coastal deserts and block solar radiation. Coastal deserts are relatively complex because they are at the juncture of terrestrial, oceanic, and atmospheric systems. A coastal desert, the Atacama of South America, is the Earth's driest desert. In the Atacama, measurable rainfall--1 millimeter or more of rain--may occur as infrequently as once every 5-20 years.

TYPES OF DESERTS• MONSON DESERT• "Monsoon," derived from an Arabic

word for "season," refers to a wind system with pronounced seasonal reversal. Monsoons develop in response to temperature variations between continents and oceans. The southeast trade winds of the Indian Ocean, for example, provide heavy summer rains in India as they move onshore. As the monsoon crosses India, it loses moisture on the eastern slopes of the Aravalli Range. The Rajasthan Desert of India and the Thar Desert of Pakistan are parts of a monsoon desert region west of the ranqe.

TYPES OF DESERTS• POLAR DESERT• Polar deserts are areas with annual

precipitation less than 250 millimeters and a mean temperature during the warmest month of less than 10° C. Polar deserts on the Earth cover nearly 5 million square kilometers and are mostly bedrock or gravel plains. Sand dunes are not prominent features in these deserts, but snow dunes occur commonly in areas where precipitation is locally more abundant. Temperature changes in polar deserts frequently cross the freezing point of water. This "freeze-thaw" alternation forms patterned textures on the ground, as much as 5 meters in diameter.

ANIMAL FOUND IN INDIAN DESERT

• Some wildlife species, which are fast vanishing in other parts of India, are found in the desert in large numbers such as the blackbuck (Antilope cervicapra), chinkara (Gazella bennettii) and Indian wild ass (Equus hemionus khur) in the Rann of Kutch

ANIMALS FOUND IN AFRICAN DESERTS

• Among the mammal species still found in the Sahara are the gerbil, jerboa, Cape hare, and desert hedgehog; Barbary sheep and scimitar-horned oryx; dorcas gazelle, dama deer, and Nubian wild ass; anubis baboon; spotted hyena, common jackal, and sand fox; and Libyan striped weasel and slender mongoose

ANIMALS FOUND IN ARCTIC DESERTS

• The animals include the reindeer, polar bear, Arctic fox, narwhal, walrus, seal, ox, moose, orca, and snowy owl. The Alaskan malamute is a powerful sled dog from Alaska. This small, white fox lives farther north than any other land animal

SUBMITTED BY :- DEVANSH CHHAPARAWAL GRADE :- IX “A”

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