Class 9th chapter Climate ppt.pptx pdf made by pranay

These are the notes of the topper who had scored 99 out of 100 in final exam these notes sre described very briefly so that you can understand the notes are very shot and the diagram are the most in the geography
I had made these by thinking that tese notes will help you in your paper I have studyed in pm shri kv no. 1 ahilyanagar Maharashtra

1. GEOGR APH y
CLIMATE

2. What is Climate?

is the characteristic condition of the
atmosphere near the earth's surface at a certain
place on earth.

It is the long-term weather of that area which
remains at least 30 years.

3. la ES
eatnerr

Weather refers to the state of
atmosphere over an area at
any point of time. The
elements of both weather

and climate are same. It is the
combination of temperature,
humidity, precipitation, wind,
cloudiness and other
atmospheric conditions at a
specific time.

5. In summer, the temperature in parts of Rajasthan Desert
is 50°C, and it is around 20°C in Pahalgam in J & K. On
a winter night, temperature at Drass in J & K may less

than -45°C, and at Tiruvananthapuram it may be of
22°C

In some places temperature between day and
night temperature differs. In the Thar Desert, it rise to
50°C, in day and drop down to near 15°C in night. But
in the Andaman and Nicobar islands or in Kerala, there
is no much difference in day and night temperatures.

6. given rise

lothes and houses

o ©) O

8. Tropic of Cancers.

Equator

Tropic of Capricorn

Precipitation in mm
< 400
400-800
800-1600

39

arctic Circle $
> #

9. Latitude
-Altitude
"Relief Features

"Distance from Sea

The Himalayan Mt.

tribution of Land & water

10. Latitude is the
distance a place
lies north or

south of the
equator and is
measured by an
imaginary line
called lines of
latitude.

The Earth

Lines of Latitude

12. Latitude

@ As latitude increases, the intensity of solar energy
decreases. Due to curvature of the Earth, the
amount of solar energy varies according to latitude.

In India, the Tropic of Cancer passes through the middle
of the country from the Rann of Kuchchh in the west to
Mizoram in the east.

Almost half of the country, lying south of the Tropic of
Cancer, belongs to the tropical area. All the remaining
area, north of the Tropic, lies in the sub-tropics.
Therefore, India's climate has characteristics of tropical
as well as subtropical climates.

13. Tropical, Temperate and Polar Zones

- The tropical zone is between 23.5° north (the tropic of
Cancer) and 23.5° south (the tropic of Capricorn) of the
Equator. The Sun’s rays are most intense and the
temperatures are always warm.

The temperate zones are between 23.5° and 66.5°
north and between 23.5° and 66.5° south of the
Equator. The Sun’s rays strike Earth at a smaller angle
than near the Equator.

Polar zones are between 66.5° north and south
latitudes and the poles. The sun’s rays strike Earth ata
very small angle in the polar zones.

15. Earth’s Major Climate Zones

16. Arctic C DN North Frigid Zone

Temperate Zone

Torrid Zone

Temperate Zone

South Frigid Zone

17. TUDE &

18. As elevation increases, the air gets cooler because of
the energy drawn from the surroundings.

19. Factors That Affect Climate

Water Bodies

Large bodies of water such as lakes and oceans have an
important effect on the temperature of an area because
the temperature of the water body influences the
temperature of the air above it.

Atmospheric Circulation

Global winds are another factor that influences climate
because they distribute heat and moisture around Earth.

20. Natural Processes That Change Climates

© Solar Activity
When the Sun is most active, it contains dark blemishes
called sunspots. The formation of sunspots appears to
correspond with warm periods in Europe and North
America.

@ Earth Motions
Geographic changes in Earth’s land and water bodies
cause changes in climate. Changes in the shape of
Earth’s orbit and the tilt of Earth on its axis are other
Earth motions that affect global climates.

21. © The Greenhouse Effect

The greenhouse effect is a natural warming of both
Earth’s lower atmosphere and Earth’s surface from solar
radiation being absorbed and emitted by the
atmosphere.

+ Global Warming

As a result of increased levels of carbon dioxide and
other greenhouse gases, global temperatures have
increased. This increase is called global warming.

22. The Pressure and Surface Winds

The pressure and wind system of any area depend on the latitude
and altitude of the place. It influences the temperature and rainfall
pattern.

The climate and weather conditions in India are governed by the
atmospheric conditions like:

+ Pressure and surface winds;

+ Upper air circulation; and

* Western cyclonic disturbances and tropical cyclones.

India lies in the north easterly winds region. These winds originate
from the subtropical high-pressure belt of the northern
hemisphere. They blow south, get deflected to the right due to the
Coriolis force and move towards equatorial low-pressure area.

24. + At the Equator, temperatures are relatively
high. Land and water masses heat up and as a

result these warm the air over them.

+ Air heated at the equatorial region rises to
the top of the atmosphere.

« More air rising beneath it forces the air mass
to spread north and south toward the poles.

25. Coriolis Effect

The rotation of the Earth causes all moving
objects in the Northern Hemisphere,
including air mass, to deflect to the right and

those in the Southern Hemisphere to move to
the left.
This Coriolis effect is absent at the Equator.

Coriolis Force- prevents a direct simple flow
from the Equator to the Poles.

This is also known as ‘Ferrel’s Law’.

26. intended path

actual path

equator

actual path

intended path

27. The Pressure and Surface Winds in India

The pressure and wind conditions in India is unique. During winter,
there is a high-pressure in the north of the Himalayas. Cold dry
winds blow from this region to the low-pressure areas over the
oceans to the south. In summer, a low-pressure area develops over
interior Asia and in north-western India. This causes a complete
reversal of the direction of winds during summer. Air moves from
the high-pressure area over the southern Indian Ocean, in a south-
easterly direction, crosses the equator, and turns right towards the
low-pressure areas over the Indian subcontinent. These are known
as the Southwest Monsoon winds. These winds blow over the
warm oceans, gather moisture and bring widespread rainfall over
the mainland of India.

28. INDIAN ©

29. MUMBAI

30. (0
|
(

32. The Rain Shadow Effect

Windward Leeward
- side
= ¿Bain shadow

- Warm,
di

34. o (®
|
(

36. Jet Stream

Streams are located at 27°-30° north latitude,
nown as subtropical westerly jet streams. Over India)
these jet streams blow south of the Himalayas, all
through the year except in summer. The western cyclonic

disturbances experienced in the north and north-western

parts of the country are brought in by this westerly flow.

In summer, the subtropical westerly jet stream moves

north of the Himalayas with the apparent movement of

the Sun. An easterly jet stream, called the tropical

easterly jet stream blows over peninsular India,/
proximately over 14°N during the summer.

38. Western Disturbances

western cyclonic disturbances are weat!

phenomena of the winter months brought in by the
westerly flow from the Mediterranean region. They
usually influence the weather of the north and north-
western regions of India. Tropical cyclones occur during
the monsoon as well as in October - November, and are
part of the easterly flow. These disturbances affect the
coastal regions of the country.

Thus very often the coast of Orissa and Andhra Pradesh
are affected by those disasters.

40. OCEAN CURRENTS

Solar energy, wind, and Earth’s rotation creates Ocean current:
Current- the systematic patters of water movement.
Gyres- two great circular water motion.

> Northern Hemisphere- the ocean current moves clockwise.
> Southern Hemisphere- the ocean current move anti-clockwise.

> Trade winds push warm surface waters westward at the equator.

> As the waters encounter the continents, they split into north-
and south-flowing currents along the eastern coast, formin;
north and south gyres.

41. Surface Water blown by the winds at point A will weirs to the
right of its initial path and continue eastward. Water at point
B weirs to the right and continues westward.

42. North

sg
eal Atlantic
[ Je j
u 5 2

q
South
And South
Pacific ( Atlantic 0
=— N

d

43. Atlantic Ocean

ES

44. Tie Kóppen Climate Classification System

© The Koppen climate classification system uses
mean monthly and annual values of temperature and
precipitation to classify climates.

© According to the Köppen classification, the earth can be

divided into several major climatic zones and bands:

> Tropical climate > Temperate climate

> Subtropical climate > Oceanic climate

> Arid climate > Continental climate

> Equatorial climate > Subarctic climate

> Semiarid climate > Polar climate

> Mediterranean climate > Climate of Antarctica

54. CL
D

| Subarctic Climate

56. Polar climates are those in which the mean temperature
of the warmest month is below 10°C.

6)

58. The climate of India is strongly influenced by
monsoon winds. The sailors who came to India in
historic times were one of the first to have noticed

the phenomenon of the monsoon. They benefited
from the reversal of the wind system as they came
by sailing ships at the mercy of winds. The Arabs,
who had also come to India as traders named this
seasonal reversal of the wind system ‘monsoon’.

59. Atmospheric Conditions over the Indian Subcontinent

in the Month of January

PACIFIC
OCEAN

een
INAN OCEAN 3;

60. Atmospheric Conditions over the Indian Subcontinent

in the Month of June

61. (a) The differential heating and cooling of land and water
creates low pressure on the landmass of India while the
seas around experience comparatively high pressure

(b)

known as

62. (ITCZ) isa prosa trough of low pressure
in equatorial latitudes. This is where the

northeast and the southeast trade winds
converge. This convergence zone lies
more or less parallel to the equator but
moves north or south with the apparent
movement of the sun.

63. (c) The prese

D r, nearly
intensity

Monsoon.

(d) The Tibetan plateau gets intensely heated

summer, results in strong vertical air currents and the
formation of low pressure over the plateau at about 9 km
above sea level.

(e) The movement of the westerly jet stream to the
north of the Himalayas and the presence of the tropical
easterly jet stream over the Indian peninsula during

summer.

65. SOUTHERN OSCILLATION

Fig.6 Normally, the trade winds and strong equatorial currents flow toward the west.
At the same time, an intense Peruvian current causes upwelling of
cold water along the west coast of South America.

66. is a name given to the
riodic development of a warm
cean current along the coast of
Peru as a temporary replacement of
the cold Peruvian current. ‘EI Nino’
is a Spanish word meaning ‘the
child’, and refers to the baby Christ,
as this current starts flowing during
Christmas. The presence of the El
Nino leads to an increase in sea-
surface temperatures and
weakening of the trade winds in the
region.

67. EL-NINO EFFECTS

68. Beginning of the Monsoon

Subsequently, it proceeds into two —
(i) the Arabian Sea branch and
(ii) the Bay of Bengal branch.

69. Beginning of the Monsoon

The Arabian Sea branch reaches Mumbai about ten days later on
approximately the 10th of June. This is a fairly rapid advance.

The Bay of Bengal branch also advances rapidly and arrives in Assam
in the first week of June. The lofty mountains causes the monsoon
winds to deflect towards the west over the Ganga plains.

By mid-June the Arabian Sea branch of the monsoon arrives over
Saurashtra-Kuchchh and the central part of the country. The Arabian
Sea and the Bay of Bengal branches of the monsoon merge over the
north-western part of the Ganga plains.

Delhi generally receives the monsoon showers from the Bay of Bengal
branch by the end of June (tentative date is 29th of June). By the July
first week, western Uttar Pradesh, Punjab, Haryana and eastern
Rajasthan experience the monsoon. By mid-July, the monsoon reaches
Himachal Pradesh and the rest of the country.

71. End of the Monsoon

Withdrawal or the retreat of the monsoon is a more gradual
process. The withdrawal of the monsoon begins in north-western

states of India by early September. By mid-October, it withdraws
completely from the northern half of the peninsula. Then it
quickly withdraw from the southern half of the peninsula. By
early December, the monsoon has totally withdrawn from the

country.

The islands receive the very first monsoon showers, from south to
north, between the last week of April and the first week of May
Then it withdraw from north to south during the first week of
December to the first week of January. By this time, the other

parts of the country is already influencing the winter monsoon

73. The Seasons

SZ

ES) a

74. OF SEASONS

75. The monsoon type of climate is characterised by a distinct

seasonal pattern. The weather conditions greatly change from one

season to the other. These changes are particularly noticeable in
the interior parts of the country. But, the coastal areas do not
experience much variation in temperature though there is variation
in rainfall pattern

In India, Four main seasons can be identified:
(i) the cold weather season,

(ii) the hot weather season,

(iii)the advancing monsoon and

(iv) the retreating monsoon with some regional variations.

76. C

OLD WEA

extends from

ebruar
hift

southern

cold wh

is not

77. The Cola € (Winter)

The cold weather season begins from mid- November in northern India and
stays till February. December and January are the coldest months. The
temperature decreases from south to the north. The average temperature of
Chennai, on the eastern coast is between 24°-25° Celsius, while in the northern
plains, it ranges between 10°-15° Celsius. Days are warm and nights are cold
Frost is common in the north and the higher slopes of the Himalayas experienc
snowfall

During winter, the northeast trade winds blow from land to sea. So, most part of
the country faces a dry season. Some amount of rainfall occurs on the Tamil
Nadu coast from these winds as, trade winds blow from sea to land

In the northern part of the country, a feeble high-pressure region develops, with
light winds moving outwards from this area. Influenced by the relief, these
winds blow through the Ganga valley from the west and the northwest. The
weather is normally marked by clear sky, low temperatures and low humidity

and feeble, variable winds.

78. on

In the northern plains, there is the inflow of cyclonic
disturbances from the west and the northwest. These low-
pressure systems, from the Mediterranean Sea and western
Asia and move into India, along with the westerly flow. They
cause the winter rains (locally known as ‘mahawat) over the

plains and snowfall in the mountains. Although the amount of
rainfall is small, it is more importance for cultivating the ‘rabi’
crops.

But, the peninsular region does not have a well-defined cold
season. There is rare seasonal change in temperature
pattern during winters due to the moderating influence of the
sea.

79. Bay of Bengal

80. WINTER RAINFALL

81. Winter

Winter is cold.

» Children dress warmly to
play in the snow.

> Animals head to their winter
homes.

82. NE

extends from March to

sun rays shif
Northern

rises

from south to

Temperature
in Kamataka
Madhya
April and
Rajasthan in May.

April 38°C

83. Due to the apparent northward movement of the Sun, the global
heat belt shifts northward. So, from March to May, it is hot weather
season in India. In March, the highest temperature is about 38°C, in
Deccan plateau. In April, temperatures in Gujarat and Madhya
Pradesh are around 42°C. In May, 45°C temperature is common in
the north-western parts of the country. In peninsular India,

temperatures remain lower due to the moderating influence of the

oceans.

The summer months experience rising temperature and falling air
pressure in the northern part of the country. By the end of May, an
elongated low-pressure area develops in the region extending from
the Thar Desert in the northwest to Patna and Chotanagpur plateau
in the east and southeast. Circulation of air begins to set in around
this tough

84. RMS IN HOT WEA!

BLOSSOM
SHOWER

86. Summer

Long, hot days.

Summer fruit and
vegetables are ready to be
picked.

You see many bees and
butterflies fly flower to
flower.

87. Advancing Monsoon (The

SOUTH WE:

June to
Septemt

Intense

Low pressure attract the
wind from the surrounding

region.
After having rains for a
few days sometime
monsoon fails to occur for
one or more weeks is

known as break in the

monsoon.

90. By early June, the low-pressure condition over the northern plains
attracts the trade winds of the southern hemisphere. These south-
east trade winds originate over the warm subtropical areas of the
southern oceans. These winds are strong and blow at an average
velocity of 30 kmph. With the exception of the extreme north-west,
the monsoon winds cover the country in about a month.

The south-west monsoon entirely changes the weather in India. The
Western Ghats receives heavy rainfall, more than 250 cm. The rain
shadow areas like Deccan Plateau and parts of Madhya Pradesh
also receives rain. The north-eastern part of the country receives
the maximum rainfall. Mawsynram in the southern ranges of the
Khasi Hills receives the highest average rainfall in the world.
Rainfall in the Ganga valley decreases from the east to the west.
Rajasthan and parts of Gujarat get scanty rainfall.

91. Breaks in Rainfall

The monsoon rains take place only for a few days at a time. They

are interspersed with rainless intervals. These breaks in monsoon

are related to the movement of the monsoon trough. The trough and

its axis keep on moving northward or southward, which determines
the spatial distribution of rainfall. Whenever the axis shifts closer
to the Himalayas, widespread rain occur in the mountainous
catchment areas of the Himalayan rivers, which also cause floods
The frequency and intensity of tropical depressions determine the
amount and duration of monsoon rains. These depressions form at
the Bay of Bengal and cross over to the mainland. The depressions
follow the axis of the “monsoon trough of low pressure”. It causes
heavy floods in one part, and droughts in the other. Sometimes it
disturbs the farming schedule of millions of farmers all over the
country

92. MONSOON SEASON

S from

Low pi e region shift
from northern parts of

India towards south.
Owing to the conditions
of high temp:

hurnidity,

become

oppressive. This
commonly known as
“October heat’

95. 100-200cm

50-100 cm

96. The Himalayas protect the subcontinent from extremely cold winds
from central Asia. This enables northern India to have uniformly
higher temperatures when compared to other areas on the same
latitudes.

Similarly, the peninsular plateau, under the influence of the sea
from three sides, has moderate temperatures.

The unifying influence of the monsoon on the Indian subcontinent
is quite perceptible. The seasonal alteration of the wind systems
and the associated weather conditions provide a rhythmic cycle of

seasons.

The Indian landscape, its animal and plant life, its entire
agricultural calendar and the life of the people, including their
festivities, revolve around this phenomenon.