3. Climates of India
Weather, Seasons and Climate
1. Difference between Weather
and Climate
In daily life, people often
use the word climate, but they actually mean weather. However,
these two are different.
Weather
- Weather refers to the day-to-day conditions
of the atmosphere.
- It includes changes like:
- Rain
- Sunshine
- Wind
- Temperature (hot or cold)
- Weather changes frequently, even within
hours or days.
👉 Example:
If it rains today but is sunny tomorrow, that is a change in weather.
Climate
- Climate refers to the long-term pattern of
weather in a place.
- It is studied over many years (decades or
more).
- Climate does not change quickly like
weather.
- Different regions have different climates.
👉 Example:
A desert has a hot and dry climate, while a hill station has a cool
climate.
2. Seasons and Their
Occurrence
Before understanding climate,
it is important to know about seasons.
What are Seasons?
- Seasons are periods of the year with
specific weather conditions.
- They occur because the Earth revolves
around the Sun.
- Each season lasts for a few months and
repeats every year.
Main Seasons
Generally, the seasons
include:
- Spring (Vasanta)
- Summer
- Monsoon (Rainy Season)
- Autumn (Sharad)
- Winter
👉 These seasons occur in a
cycle every year.
3. Relationship between
Weather, Seasons and Climate
Seasons are connected to both weather
and climate.
Weather and Seasons
- Weather changes according to the season:
- Summer → hot and dry
- Monsoon → rainy and humid
- Winter → cold
Climate and Seasons
- The pattern of seasons in a region is
closely related to its climate.
- Most parts of the world have four main
seasons:
- Spring
- Summer
- Autumn
- Winter
Special Feature of India
- India has an extra important season:
- Monsoon (Rainy Season)
- Rainfall occurs mainly during this specific
period.
4. Life and Seasons (Natural
Rhythm)
All living things adjust
according to seasons.
Human Life
- People change:
- Clothes (cotton in summer, wool
in winter)
- Food habits
- Daily activities
Plant Life
- Plants behave differently in different
seasons:
- Bloom in spring
- Shed leaves in autumn
- Change colour in some regions
Animal Life
- Animals also adapt:
- Some develop thick fur in winter
- Others change behaviour according to seasons
👉 This shows that life on Earth
follows a natural seasonal rhythm (ṛitus).
5. Stability and Change in
Climate
- Climate usually remains stable over long
periods.
- However, in recent decades, scientists have
observed changes in climate.
Cause of Climate Change
- Many changes are caused by human activities,
such as:
- Pollution
- Deforestation
- Industrial activities
Types of Climates in India
India is known for its great
diversity, and this diversity is clearly seen in its climate.
Different regions of India experience different types of climates due to
variations in location, altitude, and distance from the sea.
1. Alpine Climate (Himalayan
Region)
- Found in the northern Himalayan mountains.
- Characterised by:
- Very cold and snowy
winters
- Cool summers
- The term alpine comes from the Alps
mountains in Europe.
- People here wear thick woollen clothes
due to extreme cold.
👉 Example: High mountain
regions like Ladakh or Himachal’s upper areas.
2. Temperate Climate (Lower
Himalayas & Hill Areas)
- Found in:
- Lower Himalayan regions
- Many hilly areas of India
- Features:
- Moderately cold winters
- Pleasant, not too hot
summers
- These regions have many hill stations.
👉 Importance:
- People from hot plains visit these areas for relief
from heat.
👉 Example: Shimla, Darjeeling,
Ooty.
3. Subtropical Climate
(Northern Plains)
- Found in the northern plains of India.
- Features:
- Very hot summers
- Cold winters
- This region is important for agriculture,
especially:
- Wheat cultivation
👉 Example: Punjab, Haryana,
Uttar Pradesh.
4. Arid Climate (Thar Desert Region)
- Found in the western part of India (Thar
Desert).
- Features:
- Extremely hot days
- Cool nights
- Very little rainfall
- Due to water scarcity, people have developed special
methods to collect and store water.
👉 Example: Rajasthan desert
region.
5. Tropical Wet Climate
(Western Coastal Region)
- Found along the western coastal strip.
- Features:
- Heavy rainfall during
monsoon
- Warm and humid conditions
- This climate is ideal for growing:
- Rice
- Spices
👉 Example: Kerala, coastal
Karnataka.
6. Semi-Arid Climate (Deccan
Plateau)
- Found in the central Deccan Plateau.
- Features:
- Hot summers
- Mild winters
- Moderate rainfall during monsoon
👉 This region is not as dry as
deserts but not very wet either.
7. Tropical Climate (Eastern
India & Southern Peninsula)
- Found in:
- Eastern India
- Southern peninsula
- Features:
- Mild winters
- Clear wet and dry seasons
- Rainfall is mainly controlled by monsoon
winds.
8. Important Note
- Terms like tropical and subtropical
are related to special lines of latitude called the tropics.
- These will be explained in detail later.
Factors Determining the Climate
The climate of a place is not
decided by a single factor. It depends on many factors working together.
Some factors operate on a global scale, while others affect specific
regions or local areas.
Let us understand the main
factors:
1. Latitude (Distance from the
Equator)
What is Latitude?
- Latitude measures the distance of a place
from the Equator.
- It increases as we move north or south
of the Equator.
Effect on Climate
- Near the Equator (low latitudes) → very hot
- Away from the Equator (higher latitudes) → cooler to very cold
Reason
- The difference is due to the angle of the
Sun’s rays:
- At the Equator → Sun’s rays fall directly
(perpendicular)
→ Heat is concentrated → more temperature - Near the poles → Sun’s rays fall slanting
(oblique)
→ Heat spreads over a larger area → less temperature - Also, slanting rays pass through more
atmosphere, losing energy.
Example in India
- Kanniyakumari and Nicobar Islands
→ hot throughout the year
- Srinagar → much cooler due to higher
latitude
2. Altitude (Height above Sea
Level)
What is Altitude?
- Altitude is the height of a place above sea
level.
Effect on Climate
- As altitude increases → temperature decreases
Reasons
- Lower air density at higher altitude
- Air becomes thinner → holds less heat → cooler temperature
- Distance from Earth’s surface
- The Sun heats the Earth’s surface first
- Air farther from the surface receives less
heat
Examples
- Hill stations like:
- Munnar, Ooty (Udhagamandalam), Shimla,
Darjeeling, Nainital, Shillong, etc.
- High Himalayan peaks remain covered with
snow because temperatures stay below freezing.
3. Proximity to the Sea
(Distance from the Sea)
Effect on Climate
- Coastal areas (near sea):
- Moderate climate
- Not very hot in summer
- Not very cold in winter
- Interior areas (far from sea):
- Extreme climate
- Very hot summers
- Very cold winters
Reason
- The sea acts as a temperature moderator:
- Water heats and cools slowly
- This reduces temperature variation
Example
- Mumbai (coastal):
- Summer ~32°C
- Winter ~18°C
- Temperature range ~14°C (small variation)
- Nagpur (inland):
- Summer ~44°C
- Winter ~10°C
- Temperature range ~34°C (large variation)
4. Winds
Role of Winds
- Winds carry warm or cold air from one
place to another.
- They affect:
- Temperature
- Humidity
- Rainfall (precipitation)
Examples
- Hot winds in summer:
- Blow from deserts of Arabia and Afghanistan
- Affect states like Punjab, Haryana,
Rajasthan, Madhya Pradesh
- Cause heat waves
- Cold winds in winter:
- Come from across the Himalayas
- Cause cold waves in northern India
- Moist winds from the sea:
- Bring humidity and rainfall
👉 Winds play a key role in monsoon
rainfall.
5. Topography (Physical
Features of Land)
What is Topography?
- It refers to the physical features of a
region, such as:
- Mountains
- Plateaus
- Plains
Effect on Climate
- Landforms can block or allow winds.
Examples
- Himalayas and Karakoram ranges:
- Act as a barrier
- Protect India from cold winds of Central
Asia
- Thar Desert:
- Flat land with no barriers
- Exposed to hot, dry winds
- Western Ghats:
- Play an important role in monsoon rainfall
(explained later)
6. Combined Effect of All
Factors
- Climate is determined by the combined
influence of:
- Latitude
- Altitude
- Distance from sea
- Winds
- Topography
Climate Description Includes
- Temperature patterns
- Precipitation (rain, snow, fog, mist)
- Wind conditions
- Observed over 30 years or more
7. Microclimate (Local
Climate)
What is Microclimate?
- A small area with its own climate,
different from surrounding regions.
Features
- Unique patterns of:
- Temperature
- Humidity
- Rainfall
Examples
- Enclosed valleys
- Dense forests
- Urban Heat Islands
Urban Heat Island
- Cities with:
- Many buildings and concrete structures
- Very little vegetation
- These areas trap heat and become warmer
than nearby regions
Importance
- Microclimates affect:
- Plants and animals (flora and fauna)
- Crops grown
- Human health and well-being
The Monsoons
The monsoon season is
extremely important for life in India. It affects agriculture, water supply,
and the daily lives of people.
1. Importance of Monsoons
- During monsoon:
- Rivers fill up
- Soil becomes moist and
fertile
- Crops grow well
- Plants, animals, and
humans thrive
👉 This is why monsoons are
considered the lifeline of India.
2. Meaning of Monsoon
- The word ‘monsoon’ comes from the
Arabic word “mausim”, meaning ‘season’.
- It refers to seasonal winds that blow
over:
- Indian Ocean
- South Asia
- Africa
- Australia
👉 In common usage, “monsoon”
usually means seasonal rainfall, though technically it refers to winds.
3. Basic Mechanism of Monsoons
The monsoon system works
because:
- Land heats and cools faster than water
Key Principle
- Air moves from high pressure to low
pressure
4. Summer Monsoon (Southwest
Monsoon)
Process
- During summer:
- The Asian landmass heats up quickly
- This creates a low-pressure area over
land
- The ocean remains cooler:
- Creates a high-pressure area
- Winds move:
- From high pressure (ocean) → low pressure (land)
- These winds:
- Carry moisture from the sea
- Rise over land and condense
- Result in heavy rainfall
👉 This is known as the Southwest
Monsoon (named after the direction of winds).
5. Progress of Monsoon in
India
- Monsoon enters India from the southern
tip in early June
- Moves northward gradually
- Covers the entire country by mid-July
Important Feature
- The spread is not smooth or uniform
6. Role of Western Ghats
- The Western Ghats act as a natural barrier:
- Western slopes → receive heavy rainfall
- Eastern side (Deccan
Plateau) → receive less and
irregular rainfall
7. Winter Monsoon (Northeast
Monsoon)
Reversal of Pattern
- In winter:
- Land cools faster → becomes high pressure
- Ocean remains warmer → low pressure
- Winds now blow:
- From land → ocean
Features
- Winds are generally dry
- Bring cold weather to many parts of
India
Special Case
- Some winds pass over the Bay of Bengal
- Pick up moisture
- Bring rainfall to eastern and southern
India
👉 This is called the Northeast
Monsoon.
Climate and Our Lives
Human life is closely
connected to climate. It affects not only our daily activities but also our
culture, economy, and overall way of living.
1. Climate and Culture
- Climate influences local traditions and
lifestyles.
- In India, many festivals are linked to
seasons and agriculture.
Examples
- Harvest festivals (like Pongal, Baisakhi)
celebrate crop seasons
- Seasonal changes influence:
- Food habits
- Clothing
- Daily routines
👉 This shows that culture is
often shaped by climatic conditions.
2. Climate and Economy
Climate has a direct impact
on economic activities, especially in a country like India.
Agriculture
- Farming depends heavily on:
- Rainfall
- Temperature
- A term often used is “monsoon failure”:
- It means insufficient rainfall during
monsoon
- Leads to crop failure
Effects of Monsoon Failure
- Agriculture suffers
- Water becomes scarce
- People (especially women) may walk long
distances to fetch water
- Agricultural labourers may:
- Lose jobs
- Migrate to cities in search of work
- Food items like:
- Grains
- Vegetables
- Fruits
become costlier
👉 This leads to inflation
(rise in prices)
3. Climate and Industry
- Many industries depend on:
- Regular weather
conditions
- Availability of water
- Irregular climate can:
- Disrupt production
- Affect economic growth
4. Climate and Socioeconomic
Conditions
- Around the world, climate influences:
- Living standards
- Employment
- Availability of resources
👉 Good climate conditions → stable life
👉 Poor climate conditions → difficulties in living
Climates and Disasters
India’s diverse climate and weather patterns
sometimes lead to extreme
natural events, known as climate-related
disasters.
Impact
of Climate Disasters
These disasters:
·
Affect
human and animal life
·
Damage
agriculture
·
Destroy
infrastructure
(roads, houses, bridges)
·
Disturb
local economies
1.
Cyclones
Occurrence
·
Cyclones
mainly affect the Indian
coastline
·
The
eastern coast
is more prone to cyclones
·
Some
cyclones are highly
destructive
Effects
·
Loss
of life (humans and
animals)
·
Damage
to property and
infrastructure
·
Uprooting
of trees
·
Soil
erosion
Monitoring
·
The
India Meteorological Department tracks cyclones
·
It
provides information about:
o Formation
o Movement
o Landfall location
Formation
of Cyclones
·
Cyclones
form due to a low-pressure
system over the sea
·
Process:
1.
Air
pressure becomes low
over the sea
2.
Surrounding
air moves towards this low-pressure area
3.
Moist
air from the sea enters
4.
Strong
winds and heavy rainfall develop
·
As
winds move inward:
o They form clouds
o Rotate around the centre
Eye
of the Cyclone
·
The
centre is called the “eye”
·
It
is:
o Calm
o Cloudless
2.
Floods
What
is a Flood?
·
Flood
occurs when water
overflows onto normally dry land
Causes
·
Heavy
rainfall
·
Excess
water in:
o Rivers
o Lakes
·
Water
exceeding capacity or breaking river banks
Flood-Prone
Areas in India
·
Uttar
Pradesh
·
Bihar
·
Kerala
·
Andhra
Pradesh
·
Assam
Special
Case: Glacial Floods
·
Occur
in Himalayan regions
·
Caused
by glacial lakes
How it Happens
·
Glaciers
melt → water collects in lakes
·
Lakes
are blocked by ice and
rocks
·
If
pressure increases:
o Barrier breaks
o Sudden flood occurs →
called glacial burst
👉 These floods are very dangerous and destructive
Urban
Flooding
·
Common
in cities due to:
o Poor drainage systems
o Unplanned construction
o Blocking natural waterways
·
Concrete
surfaces (roads, buildings):
o Do not absorb water
o Increase flooding
3.
Landslides
What
is a Landslide?
·
Sudden
collapse of:
o Rock
o Soil
o Debris
Causes
·
Heavy
rainfall
·
Earthquakes
·
Volcanic
activity
Areas
Affected
·
Himalayan
states:
o Himachal Pradesh
o Uttarakhand
o Sikkim
o Arunachal Pradesh
·
Western
Ghats and other hilly regions
Human
Causes
·
Deforestation
·
Poor
construction practices
·
Too
many buildings blocking water flow
👉 Landslides often occur during the monsoon season
4.
Forest Fires
What
are Forest Fires?
·
Uncontrolled
fires that spread across:
o Forests
o Grasslands
Causes
·
Dry
climate
·
Drought
·
Strong
winds
·
Human
carelessness
(major cause)
Affected
Areas
·
Uttarakhand
·
Himachal
Pradesh
·
Madhya
Pradesh
·
Chhattisgarh
·
Western
Ghats
Effects
of Forest Fires
·
Destroy
large forest areas
·
Harm
wildlife
·
Damage
the ecosystem
·
Reduce
air quality
·
Force
people to leave their
homes
👉 Impacts are both:
·
Environmental
·
Economic
Climate Change
1. What is Climate Change?
- Climate change refers to long-term
and significant changes in climate.
- These changes may occur:
- On a global (planetary) scale
- Or in a specific region
It includes changes in:
- Temperature
- Rainfall (precipitation)
- Weather patterns and events
2. Causes of Climate Change
Natural Causes (Past)
- In earlier times (millions of years ago),
climate change was caused by:
- Natural processes
- Changes in Earth’s system
Human Causes (Present)
Since the 19th century,
climate change has mainly been caused by human activities, such as:
- Burning of fossil fuels (coal, oil, gas)
- Deforestation (cutting down forests)
- Harmful industrial practices
- Excessive consumption and wasteful lifestyles
3. Greenhouse Effect and
Global Warming
Natural Greenhouse Effect
- The Earth has a natural carbon cycle
- Gases like carbon dioxide (CO₂) trap
heat from the Sun
- This keeps the Earth warm enough to support
life
Problem: Excess Greenhouse
Gases
- Human activities release large amounts of
greenhouse gases
- This leads to:
- Extra heat being trapped
- Rise in global temperature
👉 This process is called global
warming
Impact
- Climate patterns are disturbed
- Plants, animals, and humans struggle to adapt
- Changes happen faster than natural
adaptation
4. Effects of Climate Change
(Example from India)
- Rising temperatures are noticeable in India
- Example:
- In early 2025, temperatures were 1°C
to 3°C above normal
Consequences
- Shorter and milder winters
- Impact on:
- Agriculture (crop production)
- Small-scale industries
👉 This shows how climate change
creates new challenges
5. Climate Change and
Disasters
- Climate change increases the risk of:
- Extreme weather events
- Natural disasters (floods, droughts,
cyclones)
👉 Understanding this link helps
us:
- Prepare better
- Reduce damage
6. Solutions and Actions
(Mitigation & Adaptation)
Governments around the world,
including India, are taking steps to reduce climate change.
Key Measures
- Reducing greenhouse gas emissions
- Planting more trees (afforestation)
- Promoting renewable energy (solar,
wind)
- Improving energy efficiency
- Encouraging sustainable lifestyles
7. Challenge
- These solutions sometimes conflict with
economic growth:
- Industries want to expand
- People want higher consumption
👉 This creates a balance
problem between:
- Development
- Environmental protection
*******
Questions and activities
1.
Match the Climatic Factors with Their Effects
|
Column A |
Column B |
Answer |
|
(1)
Latitude |
Creates
different climates in the north and south |
(b) |
|
(2)
Altitude |
Keeps
higher places cooler |
(c) |
|
(3)
Proximity to ocean |
Moderates
the temperature |
(d) |
|
(4)
Monsoon winds |
Brings
wet air to India during summer |
(a) |
2.
Answer the Following Questions
(a)
Difference between Weather and Climate
·
Weather:
o Short-term condition of the
atmosphere
o Changes daily (rain, sunshine, wind,
etc.)
·
Climate:
o Long-term pattern of weather
o Observed over many years
(b)
Why do places near the ocean have milder temperatures?
·
The
sea heats and cools slowly
·
It
acts as a temperature
moderator
·
So:
o Summers are not very hot
o Winters are not very cold
(c)
Role of Monsoon Winds in India’s Climate
·
Monsoon
winds bring seasonal
rainfall
·
In
summer:
o Winds blow from sea to land
o Carry moisture → cause rain
·
In
winter:
o Winds blow from land to sea
o Mostly dry
👉 They are very important for:
·
Agriculture
·
Water
supply
(d)
Why is Chennai hot while Leh is cold?
·
Chennai:
o Near the sea
o At low altitude
o Close to the Equator
o →
Warm/hot climate
·
Leh:
o Located at high altitude in mountains
o Temperature decreases with height
o →
Very cold climate
3.
Climate of Given Cities
|
City |
Location Type |
Climate Type |
Reason |
|
Leh |
Mountains (Himalayas) |
Alpine |
High altitude →
very cold |
|
Chennai |
Coastal |
Tropical |
Near sea →
warm & humid |
|
Delhi |
Inland plains |
Subtropical |
Far from sea →
extreme temps |
|
Panaji |
Coastal (Goa) |
Tropical wet |
Heavy rainfall, near sea |
|
Jaipur |
Desert (Rajasthan) |
Arid |
Very little rainfall |
4.
Monsoon Cycle (How to Draw on Map)
Summer
Monsoon (Southwest)
·
Draw
arrows from:
o Arabian Sea & Bay of Bengal → towards India
·
Show:
o Winds entering from southwest direction
·
Mark
heavy rainfall on:
o Western coast
o Northeast India
Winter
Monsoon (Northeast)
·
Draw
arrows:
o From land → towards sea
·
Show:
o Winds blowing from northeast direction
·
Mark
rainfall in:
o Tamil Nadu (southeast coast)
5.
Poster on Festivals (Ideas)
Include:
·
Baisakhi →
Harvest festival (Punjab)
·
Onam →
Harvest & monsoon (Kerala)
·
Pongal →
Harvest (Tamil Nadu)
·
Makar
Sankranti →
Seasonal change
👉 Add:
·
Drawings
of crops, farmers, celebrations
·
Bright
colours and labels
6.
Diary Entry (Farmer Preparing for Rainy Season)
Date: 10 June
Today I started preparing my fields
for the coming monsoon. I ploughed the land and made channels so that rainwater
can be properly stored. I have also bought good quality seeds for sowing.
The monsoon is very important for
us. If the rains are good, our crops will grow well and we will have a good
harvest. I am also repairing the bunds around my field to prevent soil erosion.
I hope the rains arrive on time this
year. My family and I are depending on it.
7.
Short Essay: Floods
Floods:
Causes, Impacts and Solutions
Causes
·
Heavy
rainfall
·
Overflowing
rivers
·
Poor
drainage systems
·
Urbanisation
blocking water flow
Impacts
·
Loss
of life and property
·
Damage
to crops
·
Water
contamination
·
Displacement
of people
Solutions
Individuals
·
Avoid
dumping waste in drains
·
Be
prepared for emergencies
Communities
·
Maintain
drainage systems
·
Create
awareness
Government
·
Build
dams and flood barriers
·
Improve
drainage and planning
·
Provide
early warnings
Conclusion
Floods are dangerous but their
impact can be reduced through proper
planning and cooperation.
*****