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Tropical cyclones originate over the Bay of Bengal and the Indian Ocean. These tropical cyclones have very high wind velocity and heavy rainfall and hit the Tamil Nadu, Andhra Pradesh and Orissa coast. Only coastal areas of Tamil Nadu receive rainfall from South-east monsoon.

The highest natural ground surface temperature ever recorded was 56.7 °C (134.1 °F) at Furnace Creek, California, United States on 10 July 1913. In recent years a ground temperature of 84 °C (183.2 °F) has been recorded in Port Sudan, Sudan.

Structure of atmosphere

1 Troposphere- this is the lowermost layer of the atmosphere . It's average height is 16 km , although it is only 10 km at the poles than at the equator . Temperature decreases with height in This layer , roughly at the rate of 1 degree Celsius for 165 metres ( or consequently 0. 65 degree Celsius per 100 meters ) of ascent . This is known as normal lapse rate . 2. Stratosphere- it extends uoto height of 50 km . It is thicker at the poles than at the equator the Temperature remains almost constant in its lower portion uoto a height of 20 km consequently , it is known as stratosphere. 3 Mesosphere - it lies above stratosphere and extends from 50to 90 km . 4. Heterosphere ( thermosphere ) - heterosphere extends above the homosphere i.e . Above the level of Mesosphere . It has hetrogeneous chemical composition with alter structure of nitrogen, oxygen , helium and hydrogen. 5 . Ionosphere - it extends from 100 to 400 km and lies above Mesosphere . It contains electrically charged particles which are known as ions, hence Thus layer is called ionosphere 6. Exosphere - the upper most layer of the atmosphere beyond the ionosphere above a height of about 400 km is known as exosphere

Urban forestry is the plantation of trees in and around public centres like parks, roadside, green belts, tourists place etc while rural forestry is the plantation of trees in agricultural land that is Agro based forestry and commercial forestry.

• Forests and wildlife preserve our life support systems, i.e., water, air and soil. For example, the plants, animals and micro-organisms recreate the quality of the air we breathe, the water we drink and the soil that produces our food without which we cannot survive.
• It also preserves the genetic diversity of plants and animals for better growth and breeding of species. For example, in agriculture we are still dependent on traditional crop varieties.
• Fisheries too are heavily dependent on the maintenance of aquatic biodiversity.
• Forests are primary producers on which all other living beings depend not only for food but indirectly for many other forest produces which are used for varied purposes.

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Tropical evergreen forests are dense, multi-layered, and harbour many types of plants and animals. These forests are found in the areas receiving heavy rainfall (more than 200 cm annual rainfall). They are very dense. Even the sunlight does not reach the ground. Two characteristics of tropical evergreen forests are that they always appear green as all the trees do not shed their leaves at the same time. Secondly, these forests are dense and the trees are more than 60 m in height.

1. Brahmaputra is one of the largest rivers of the world. It is a trans-Himalayan river.
2. It has its origin in Kailash range near Mansarover lake. It flows eastward longitudinally from a distance of 1200 km. It forms a gorge in Namcha Barwa mountains.
3. It enters India forming the gorge. It receives Dibang and Lohit rivers as its tributaries.
4. The Brahmaputra is known for its floods. This is due to the fact that both the Purvanchal Himalayas and the Shillong Plateaus receive heavy rainfall.

1. The great river system comprises large water wealth of the country.
2. The volume of annual precipitation in the country is estimated at about 3700400 million cubic meters.
3. Large rivers have great water power potential. Large rivers and lakes possess some important and useful waterways of the country.
4. The country has navigable waterways of about 10600 km. The rivers also supply water to cities, villages and industrial sectors.

Gorge : The rivers in the mountainous region cut deep valleys and flow through these valleys. These are called gorges. The gorges are steep-sloped and deep.

 

Rift valley : Rift valleys are formed due to faulting. Due to the internal disturbances of the earth, some regions sink and form a valley. This valley is called a rift valley.

1. 

Consequent rivers	Antecedent rivers
1.	These rivers	1.	It is an uplift area,
	maintain their		the rivers flow in
	original shape,		the direction
	deposit, the rise of		resulting as a
	the land due to		consequence of the
	folding. Rivers		slope.
	keep on flowing in
	the original direction.
2.	These rivers are	2.	These rivers are
	older than the fold		formed after the
	mountains over		uplift of the area.
	which these rivers
	flow.
3.	These rivers cut	3.	These rivers do
	deep gorges due to		not form gorges.
	down cutting.
4.	The trans Hima	4.	The rivers in the
	layan rivers such		peninsular India
	as Indus, Satluj,		flowing eastward
	Kosi, represent		according to slope
	consequent rivers.		are antecedent
			rivers.

Thanks ??

2. 

Antecedent rivers
1.	It is an uplift area,
	the rivers flow in
	the direction
	resulting as a
	consequence of the
	slope.
2.	These rivers are
	formed after the
	uplift of the area.
3.	These rivers do
	not form gorges.
4.	The rivers in the
	peninsular India
	flowing eastward
	according to slope
	are antecedent

1. These rivers are again subdi­vided into two groups. Trans Himalayan and Hima­layan. The Trans-Himalayan Rivers originate beyond the Great Himalayas. These are the Indus, the Sutlej and the Brahmaputra rivers. Himalayan rivers are those which originate in the Himalayas and flow through the Northern Plains, e.g., the Ganga, the Yamuna and their tributaries. These rivers are useful for irrigation and navigation and the lowlands drained by them have fertile alluvial deposits.

1. The water vapour content of the air  

This is produced by normal living activities such as washing, cooking, bathing, etc., and can be controlled by the use of extractor fans, cowlings, and ventilation at appropriate places.

2. Inside room temperature

This can be controlled to some extent by replacing single glazing with energy-efficient double or triple glazing, thereby maintaining a higher surface temperature of the glass on the room side.

3. Outside temperature   

This cannot be controlled, but its effect on the inside room temperature can be reduced by the installation of energy efficient double or triple glazing.

• Seismic waves can tell us a lot about the internal structure of the Earth because these waves travel at different speeds in different materials.
• Reflection causes P and S waves to rebound whereas refraction makes waves move in different directions.
• The variations in the direction of these waves are inferred with the help of their record on seismograph.
• Change in densities greatly varies the wave velocity. By observing the changes in velocity, the density of the earth as a whole can be estimated. By the observing the changes in direction of the waves (emergence of shadow zones), different layers can be identified.
• For both kinds of waves, the speed at which the wave travels also depends on the properties of the material through which it is traveling.
• Scientists are able to learn about Earth’s internal structure by measuring the arrival of seismic waves at stations around the world.
• For example, we know that Earth’s outer core is liquid because s-waves are not able to pass through it; when an earthquake occurs there is a “shadow zone” on the opposite side of the earth where no s-waves arrive.
• Similarly, we know that the earth has a solid inner core because some p-waves are reflected off the boundary between the inner core and the outer core.
• By measuring the time it takes for seismic waves to travel along many different paths through the earth, we can figure out the velocity structure of the earth.
• Abrupt changes in velocity with depth correspond to boundaries between different layers of the Earth composed of different materials.

The structure of Earth’s deep interior cannot be studied directly. But geologists use seismic (earthquake) waves to determine the depths of layers of molten and semi-molten material within Earth. Geologists are now using these records to establish the structure of Earth’s interior.

Earthquakes are caused by a sudden release of stress along faults in earth's crust .The continuous motion of tectonic plates causes a steady build up of pressure in rock strata on both sides of a fault until the stress is sufficiently great that it is released in sudden,jerky movement .

At the time of the origin of the earth every planet and meteorites were floating in the space and the materials of the earth were same as that of the meteorites. So, the scientists can calculate the composition of rocks ofthe earth by studying the materials found in the meteorites.

I mean plastic pollution of bibliography?

Waves are oscillatory movements in water, manifested by an alternate rise and fall of the sea surface. In other words, waves are actually the energy, not the water as such, which moves across the ocean surface. Water particles only travel in a small circle as a wave passes. The maximum wave height is determined by the strength of the wind, i.e. how long it blows and the area over which it blows in a single direction. Waves travel because wind pushes the water body in its course while gravity pulls the crests of the waves downward. The falling water pushes the former troughs upward, and the wave moves to a new position. The actual motion of the water beneath the waves is circular. It indicates that things are earned up and forward as the wave approaches, and down and back as it passes.

The air containing moisture to its full capacity at a given temperature is said to be saturated. It means that the air at the given temperature is incapable of holding any additional amount of moisture at that stage. The temperature at which saturation occurs in a given sample of air is known as dew point.

The evidences in support of continental drift theory are :

(i)The matching of continents :  The shorelines of Africa and Sout America facing each other have a remarkable and unmistakable match.

(ii)Rocks of same age across the oceans :The belt of ancient rocks of 2000 millions years ages from Brazil coast matches with those from western Africa.

(iii)Tillite: These are the sedimentary rocks formed out of deposits of glaciers. The Gondwana system of sediments from India is known to have its counterparts in six different landmasses Southern Hemisphere. The glacial tillites provide unambiguous evidences of palaeoclimates and also of drifting of continents.

(iv)Placer deposits : The occurrence of rich placer deposits of gold in Ghana coast and the complete absence of source rock in the region is an amazing fact. The gold bearing veins are in Brazil and it can be inferred that the gold deposits of Ghana were derived from the Brazil Plateau when the two continents lay side by side.

(v)Distribution of fossils : The similar species of plants and animals are found in different parts of Gondwanaland. The observations that Lemurs occur in India, Madagascar and Africa led some to consider a contiguous landmass “Lemuria” linking these three landmasses.

Bgjinh

A landform is a natural or artificial feature of the solid surface of the Earth or other planetary body. Landforms together make up a given terrain, and their arrangement in the landscape is known as topography. landforms include hills, mountains, plateaus, canyons, and valleys, as well as shoreline features such as bays, peninsulas, and seas, including submerged features such as mid-ocean ridges, volcanoes, and the great ocean basins.

<a data-ved="2ahUKEwihrPKuy9_tAhXPIbcAHZjoCKgQ9QF6BAgUEAE" href="https://www.google.com/search?q=How+such+landform+is+formed?&rlz=1C1CHBD_enIN888IN888&sxsrf=ALeKk01aV4VdiqQKjJt4Sj_usCCHOEC6Cw:1608571382709&tbm=isch&source=iu&ictx=1&fir=T2gQzD_nlYj0yM%252C_4YddOSmHkYZEM%252C_&vet=1&usg=AI4_-kQwahySom08RZeBlggUdxcy9Ewxww&sa=X&ved=2ahUKEwihrPKuy9_tAhXPIbcAHZjoCKgQ9QF6BAgUEAE#imgrc=T2gQzD_nlYj0yM"></a>

Landforms are categorized by characteristic physical attributes such as elevation, slope, orientation, stratification, rock exposure, and soil type. ... Tectonic plate movement under the Earth can create landforms by pushing up mountains and hills. Tectonic plate movement under the Earth can create landforms by pushing up mountains and hills. Erosion by water and wind can wear down land and create landforms like valleys and canyons. Both processes happen over a long period of time, sometimes millions of years.

Rivers in India are important because of the following reasons ? Religious reason. Rivers are considered very sacred symbol in hindu mythology. ?Economic development. Rivers are very important through economic point of view. They provide water for irrigation, industrial, and many other uses. ?Navigation. They are very useful in navigating boats, submarine etc ?Water transport. They are very useful and efficient for water transportation as they are relatively cheaper than other means of transport, causes less pollution and uses less fuel. ? Environment. Rivers stimulate environment by spreading greenery from where they flow by providing them water, nutrients, slit from mountains etc. ?Electricity. By constructing dams over rivers we can produce electricity.

Sea-Floor Spreading
During World War II, geologists employed by the military carried out studies of the sea floor, a part of the Earth that had received little scientific study. The purpose of these studies was to understand the topography of the sea floor to find hiding places for both Allied and enemy submarines. The topographic studies involved measuring the depth to the sea floor. These studies revealed the presence of two important topographic features of the ocean floor:

• Oceanic Ridges - long sinuous ridges that occupy the middle of the Atlantic Ocean and the eastern part of the Pacific Ocean.
• Oceanic Trenches - deep trenches along the margins of continents, particularly surrounding the Pacific Ocean.

Plate Tectonics By combining the sea floor spreading theory with continental drift and information on global seismicity, the new theory of Plate Tectonics became a coherent theory to explain crustal movements.
Plates are composed of lithosphere, about 100 km thick, that "float" on the ductile asthenosphere.
While the continents do indeed appear to drift, they do so only because they are part of larger plates that float and move horizontally on the upper mantle asthenosphere. The plates behave as rigid bodies with some ability to flex, but deformation occurs mainly along the boundaries