Chapter- 3 Climates of India

 Chapter- 3 Climates of India

1. Difference Between Weather and Climate

• Weather is the daily or hourly condition of the atmosphere—such as rain, sunshine, or wind—and changes frequently.
• Climate is the average pattern of weather in a region over a long period (decades or more).

2. What Are Seasons?

• Seasons are caused by the Earth's movement around the Sun.
• Each season lasts a few months and recurs every year.
• Common seasons include spring, summer, autumn, winter, and in India, the monsoon (rainy season).

3. Relationship Between Weather, Climate, and Seasons

• Seasons influence weather—for example, summer is hot and dry, while the monsoon brings rain.
• Climate influences seasons—regions with different climates experience different patterns of seasons.

4. Seasons and Life on Earth

• Human, plant, and animal life adapt to the changing seasons:
• Crops and food habits vary with the season.
• Clothes change with the temperature.
• Plants bloom or shed leaves, and animals may grow thicker fur in winter.

5. Climate Change

• Normally, climate stays stable over long periods.
• But in recent decades, scientists have noticed climate changes around the world.
• Many of these changes are caused by human activities (like pollution, deforestation, and burning fossil fuels).

6. Recap: Weather, Seasons, and Climate

• Weather: What we experience daily—hot, cold, rainy, windy, etc.
• Seasons: Repeat every year. Each season has different weather patterns.
• Climate: The average weather pattern in a region over many years.

Types of Climates in India:- India’s climate is as diverse as its people and landscapes. Here's how it varies across different regions:

1. Alpine Climate – Northern Himalayas

• Winters: Very cold and snowy
• Summers: Cool
• Clothing: Thick woollens needed
• Example: Upper Himalayas
• Similar to the Alps in Europe

2. Temperate Climate – Lower Himalayas and Hilly Areas

• Winters: Moderately cold
• Summers: Pleasant, not too hot
• Popular for hill stations like Shimla or Darjeeling

3. Subtropical Climate – Northern Plains

• Summers: Very hot
• Winters: Cold
• Crops: Ideal for growing wheat

4. Arid Climate – Western India (Thar Desert)

• Days: Extremely hot
• Nights: Cool
• Rainfall: Very little
• People use innovative methods to save water

5. Tropical Wet Climate – Western Coastal Strip

• Rainfall: Heavy during monsoon
• Climate: Hot and humid
• Crops: Rice, spices thrive here

6. Semi-Arid Climate – Central Deccan Plateau

• Summers: Hot
• Winters: Mild
• Rainfall: Moderate during rainy season

7. Tropical Climate – Eastern India & Southern Peninsula

• Winter: Mild
• Rainfall: Wet and dry periods based on monsoon winds
• Very dependent on monsoon for farming and water

Factors Determining the Climate

Different places have different climates because of various factors. Some of these act on a global scale, while others are local. 

a) Latitude – Distance from the Equator:- Latitude refers to how far a place is from the Equator (the imaginary line around the middle of the Earth).

How Sunlight Affects Temperature:

Near the Equator (Low Latitudes):

• Sun’s rays fall directly (almost vertically).
• Energy is concentrated on a small area.
• Result: Hotter climate.
• Examples in India: Kanniyakumari, Nicobar Islands (hot most of the year).

Near the Poles (High Latitudes):

• Sun’s rays are slanted (oblique).
• Energy is spread out over a large area.
• Rays also pass through more of the atmosphere, losing more energy.
• Result: Colder climate.
• Example in India: Srinagar (cooler temperatures).

b) Altitude – Height Above Sea Level:- Have you noticed that hill stations like Ooty, Shimla, or Darjeeling are much cooler than the plains? That’s because they are at a higher altitude.

How Does Altitude Affect Temperature?

• As you go higher up, the temperature gets cooler. Here’s why:
• Lower Air Pressure at Higher Altitudes
• As you go up, the air becomes thinner (less dense).
• Thin air holds less heat, so it feels cooler.
• Heat Comes from the Earth's Surface
• The Sun heats the Earth’s surface, and the surface warms the air.
• The higher you go, the farther you are from the warm surface, so it's colder.

Example: The Himalayas:- Many Himalayan peaks are so high that the temperature stays below freezing, keeping them covered in snow all year.

Examples of Cool Hill Stations in India:

• South: Ooty, Munnar, Madikeri, Mahabaleshwar
• North: Shimla, Nainital, Darjeeling, Tawang
• Northeast: Shillong

c) Proximity to the Sea – Nearness to Water Bodies:- Places that are close to the sea have milder climates. This means:

• Summers aren’t too hot
• Winters aren’t too cold
• This happens because the sea acts like a temperature controller, or a moderator.

Why Does This Happen?:- Water heats up and cools down more slowly than land. So, during:

• Summer: The sea absorbs heat and keeps the land cooler.
• Winter: The sea slowly releases stored heat, keeping the land warmer.
• As a result, coastal areas stay more comfortable all year round.

Example: Mumbai vs. Nagpur

Both cities are at similar latitudes, but:

Feature                     Mumbai (Near the Sea)                     Nagpur (Inland)

Summer                             ~32°C                                                 ~44°C

Winter                             ~18°C                                                 ~10°C

Temperature Range                14°C                                                    34°C

Finally we can say Mumbai has a smaller range in temperature and a more moderate climate, while Nagpur experiences extreme temperatures.

d) Winds – Moving Air that Affects Climate:- Winds carry air from one region to another. Depending on where the wind comes from, it can bring heat, cold, dryness, or moisture.

How Do Winds Influence Climate?

• Hot and Dry Winds
• Example: Punjab, Haryana, Rajasthan, Madhya Pradesh
• Winds come from the west, traveling over Arabian and Afghan deserts.
• These winds are dry and hot, causing heat waves in summer.

Cold Winds

• In winter, cold winds blow down from the Himalayas.
• These winds bring cold waves to the Himalayan foothills and nearby areas.
• Moist Winds (From the Sea)
• Winds that come from the sea carry moisture.
• These can lead to rainfall when they move over land.
• An important example is the monsoon winds, which we’ll study next.

Winds Also Affect:

• Temperature (can warm or cool a place)
• Humidity (amount of moisture in the air)
• Precipitation (rain or snow)

e) Topography – Physical Features of the Land:- Topography means the shape and features of the land, including mountains, valleys, slopes, coasts, and plains. These physical features have a major influence on the climate of a region.

How Does Topography Affect Climate?

• Mountains as Barriers
• Example: The Himalayas and the Karakoram ranges
• These high mountain ranges block cold winds from Central Asia, helping keep northern India warmer in winter than it would otherwise be.

Flat Land Offers No Protection

• Example: The Thar Desert
• Its flat, open land means there’s nothing to block hot, dry winds, making it extremely hot and arid.
• The Western Ghats also play a role by blocking moist monsoon winds, causing heavy rainfall on one side and dry conditions on the other (this will be explained in the next section).

The Monsoons – Monsoons are seasonal winds that bring heavy rainfall in summer and dry conditions in winter. They are vital for agriculture, rivers, drinking water, and life in general across India.

What Does the Word 'Monsoon' Mean?

• Comes from the Arabic word mausim, meaning “season.”
• Refers to seasonal winds in the Indian Ocean region, affecting countries like India, Australia, and parts of Africa and Southeast Asia.

How Monsoons Work:- Land heats and cools faster than the sea.

Summer Monsoon (Southwest Monsoon)

Feature                                                                     Description

Direction                                             Winds blow from sea to land (southwest direction)

What happens                                     Land heats up → creates low pressure

Wind movement                             Moist winds are pulled in from the ocean

Result                                     Heavy rainfall across India (especially on the west coast and northeast)

Timing                                     Starts in early June from the south, spreads across India by mid-July

The Western Ghats play a big role here:

• Their western slopes get heavy rain.
• Eastern side (Deccan Plateau) gets less rain — this is called the rain shadow area.

Winter Monsoon (Northeast Monsoon)

Feature                                                             Description

Direction                                 Winds blow from land to sea (northeast direction)

What happens                          Land cools faster → becomes high pressure

Wind movement                  Winds flow out from land to sea

Special case                           Some winds pass over Bay of Bengal, pick up moisture, and bring rain to                                                    east and southeast India (like Tamil Nadu)

Timing                                    From October to December

Climate and Our Lives:- Climate doesn’t just affect the weather — it affects everything we do. From culture and festivals to farming, jobs, water, and even the economy, our lives are closely connected with the climate.

1. Climate and Culture

• Many of India’s festivals are linked to seasons and agriculture.
• Example: Pongal, Baisakhi, Onam, and Makar Sankranti are all linked to harvest seasons.
• The changing seasons influence what we wear, eat, and even how we celebrate.

2. Climate and Economy

• Agriculture depends heavily on the monsoon.
• If the monsoon fails (i.e., there’s very little rainfall), it causes many problems:
• Poor crop growth
• Water scarcity – especially hard on women, who often walk long distances to fetch water
• Migration – farm workers may move to cities to find work
• Higher food prices – this leads to inflation (everything becomes more expensive)

3. Impact on Industry

• Many industries need predictable weather and plenty of water.
• When the climate is unpredictable, industries can suffer, affecting jobs and production.

4. Climate Disasters

• Floods, droughts, cyclones, and heatwaves can all disrupt lives and damage homes, farms, and businesses.
• These events put extra pressure on people and the economy — especially in poorer regions.

a. Cyclones

• Cyclones are powerful storms with very strong winds and heavy rain.
• They form mostly over the warm waters of the ocean.
• The Indian coastline, especially the eastern coast, faces many cyclones every year.

How Are Cyclones Formed?

• Sometimes, the air pressure over the sea drops below the surrounding areas, creating a low-pressure system.
• Air from surrounding areas rushes in to fill this low-pressure zone.
• This incoming air carries moisture, which forms clouds and rain.
• When the system grows stronger, winds spin and gather speed, forming a cyclone.
• At the center of the cyclone is the ‘eye’, a calm and cloudless area surrounded by violent winds.

Effects of Cyclones

• Loss of human and animal lives.
• Damage to houses, buildings, and infrastructure.
• Uprooting of trees.
• Soil erosion leading to land degradation.
• Disruption of local economies and agriculture.

Monitoring Cyclones:- The India Meteorological Department (IMD) tracks cyclones carefully.

• They provide warnings about:
• Where a cyclone is forming.
• How it’s developing.
• When and where it will make landfall.
• This helps people prepare and reduces loss.

b. Floods:- A flood happens when water overflows into areas that are usually dry.

Causes include:

• Heavy rainfall creating lots of runoff water that the land can’t soak up.
• Rivers, lakes, or reservoirs getting so full that their banks overflow or break.

When and Where Do Floods Occur?

• Floods are very common during the monsoon season.
• Some states in India that are especially prone to floods include:
• Uttar Pradesh, Bihar, Kerala, Andhra Pradesh, Assam.
• In the Himalayan regions, floods can happen due to glacial bursts.

What Is a Glacial Burst?

• Glacial lakes form behind natural barriers of rocks and ice.
• These lakes collect water from melting glaciers.
• If glaciers melt too fast or heavy rainfall occurs, the water pressure increases.
• Eventually, the barrier breaks, releasing huge amounts of water suddenly.
• This is called a glacial burst and causes serious damage downstream.

Urban Flooding

• Cities also face floods when:
• Drainage systems can’t handle heavy rain.
• Construction blocks natural water flow.
• Surfaces like concrete or asphalt don’t absorb water, causing runoff to pool.

Effects of Floods

• Damage to homes and property.
• Disruption of daily life and transportation.
• Loss of crops and livestock.
• Spread of waterborne diseases.

c. Landslides:-  A landslide is the sudden fall or slide of rock, soil, or debris down a slope.

Often triggered by:- Heavy rain, Earthquakes, Volcanic activity

Where Do Landslides Happen?:- Common in hilly and mountainous regions such as:

• Himachal Pradesh
• Uttarakhand
• Sikkim
• Arunachal Pradesh
• Western Ghats
• Usually occur during the monsoon season due to heavy rainfall.

Causes of Increased Landslides

• Human activities such as:
• Cutting down forests (deforestation)
• Poorly planned infrastructure
• Construction blocking natural water flow
• These make slopes unstable and increase landslide risks.

d. Forest Fires:- Uncontrolled fires that spread quickly through vegetation. Fueled by:

• Dry weather
• Drought
• Strong winds
• Human carelessness (accidental fires)
• Where Are Forest Fires Common?

States with large forest or grassland areas, such as:

• Uttarakhand
• Himachal Pradesh
• Madhya Pradesh
• Chhattisgarh
• Western Ghats

Effects of Forest Fires:- 

• Destruction of large forest areas.
• Harm to wildlife.
• Damage to ecosystems.
• Poor air quality.
• Displacement of local communities.
• Significant environmental and economic losses.

Climate Change:- Climate change refers to long-term changes in:

• Temperature
• Rainfall patterns
• Weather events
• It can occur globally or regionally.

Natural vs. Human-Caused Change:- In the past, climate change happened due to natural processes (like volcanic eruptions, ocean currents, etc.).

• Since the 19th century, the major cause has been human activity, especially:
• Burning fossil fuels (coal, oil, gas)
• Deforestation
• Polluting industries
• Overconsumption and waste

The Greenhouse Effect:-Earth’s atmosphere naturally traps some of the Sun’s heat – this is called the greenhouse effect and it keeps the planet warm enough for life. Human activities release too many greenhouse gases, like carbon dioxide (CO₂).

This causes:

• Extra heat to get trapped
• Global warming
• Disruption of natural climate patterns

Effects in India:- Example: In early 2025, India had temperatures 1–3°C above normal.

• Shorter, milder winters
• Poor agricultural output
• Disrupted small industries

Why It Matters:- Climate change increases the risk of disasters like floods, heatwaves, and droughts. 

It affects:

• Farming
• Economy
• Health
• Water and food security

What Can Be Done?:- Governments and people can take action through:

• Reducing emissions
• Planting more trees
• Using renewable energy (like solar or wind)
• Saving energy
• Sustainable living (less waste, more reuse)

However, this often conflicts with economic growth and high consumption.

NCERT QUESTIONS

1.  Match the climatic factors with their effects:

 Column A                                                Column B

 (1) Latitude                                                  (a) Brings wet air to India during summer

 (2) Altitude                                                  (b) Creates different climates in 

 (3) Proximity to the ocean                           (c)  Keeps higher places cooler 

 (4) Monsoon winds                                      (d) Moderates the temperature

Answer:- (1 -b)   (2-c)   (3-d)    (4-a)

2.  Answer the following questions:

 a) What is the difference between weather and climate?

 b) Why do places near the ocean have milder temperatures than places far away from it?

 c) What role do monsoon winds play in affecting India’s climate?

 d) Why is Chennai warm or hot throughout the year, while Leh is cold?

Answer:- 

a) :-

• Weather is the daily condition of the atmosphere (like rain, heat, or wind).
• Climate is the average weather pattern of a place over a long period (30+ years).

b) :- The ocean moderates the temperature by cooling the land in summer and warming it in winter, making coastal areas milder.

c):- Monsoon winds bring seasonal rainfall, which is crucial for agriculture and water supply in India.

d):-

• Chennai is near the Equator and at sea level, so it stays warm.
• Leh is at a high altitude, so it remains cold most of the year.

 3.  Look at a map of India given at the end of this book. Identify the climate for these cities — Leh, Chennai, Delhi, Panaji and Jaipur.

• Is the place near the sea, in the mountains, or in the desert? 
• How do these factors affect the climate there?

Answer:- 1. Leh (Ladakh, Jammu & Kashmir)

• Location: In the Himalayan mountains, at a high altitude
• Climate: Cold alpine climate — very cold winters, cool summers
• Effect of location: High altitude means thinner air and lower temperatures year-round. Snowfall is common in winter.

2. Chennai (Tamil Nadu)

• Location: On the eastern coast, near the Bay of Bengal
• Climate: Tropical climate — hot and humid throughout the year
• Effect of location: Being near the sea, Chennai has milder temperature changes. It receives rainfall from the northeast monsoon in winter.

3. Delhi

• Location: In the northern plains, away from the sea
• Climate: Subtropical — very hot summers and cold winters
• Effect of location: Distance from the sea means more extreme temperatures. Surrounded by land, so no sea breeze to moderate the climate.

4. Panaji (Goa)

• Location: On the western coast, near the Arabian Sea
• Climate: Tropical wet climate — warm and receives heavy rainfall during the southwest monsoon
• Effect of location: Coastal location moderates temperature and brings lots of rain in monsoon months.

5. Jaipur (Rajasthan)

• Location: In or near the Thar Desert, inland
• Climate: Arid or semi-arid — very hot summers, cool nights, and low rainfall
• Effect of location: Desert region means dry and extreme weather. Lack of vegetation and moisture makes it hotter during the day and cooler at night.

These factors — proximity to sea, altitude, and topography — play a major role in shaping the climate of each place.

                                                                

 Q. 6.  Imagine you are a farmer in India. Write a short diary entry about how you would prepare for the rainy season.

Answer:- Diary Entry – June 5 (Mention any date during Rainy Season)

Today, the sky looked heavy with clouds. The monsoon is almost here, and I must get everything ready. I checked the fields to make sure the bunds are strong and won’t let water wash away the soil. We cleaned the canals and checked the pump sets too. Tomorrow, I will buy the paddy seeds and fertilizers. My wife is drying the grain sacks and covering the stored grain to keep it safe from the rain. This is the most important season for us — if the rains come on time, we will have a good harvest.

Q.  7.  Identify a natural disaster (e.g., cyclone, flood, landslide, or forest fire) and write a short essay that includes the causes and impacts. Suggest actions that individuals, communities and the government can take to reduce the impact.

Answer:- Floods in India

Floods are one of the most common natural disasters in India. They are mainly caused by heavy rainfall, overflowing rivers, glacial bursts, and poor urban drainage. During monsoon season, areas like Bihar, Assam, and Kerala often face severe flooding.

The impacts of floods are serious: homes are destroyed, crops are damaged, people lose their belongings, and diseases can spread through dirty water. Roads, bridges, and power lines also get damaged, affecting daily life and the economy.

To reduce the impact of floods:

• Individuals should keep emergency kits ready, avoid building on floodplains, and listen to weather alerts.
• Communities can keep drains clean, build raised platforms for shelter, and help each other during rescue and relief.
• The government should build strong embankments, improve drainage systems, plant more trees, and provide early warning systems.