Geography Notes Chapter 5 Temperature Class 6 Maharashtra Board

1. What is Temperature?

• Temperature is the measure of heat in the air at a particular place.
• The Sun is the main source of heat for the Earth.
• Temperature affects weather, climate, and living conditions.

2. How Sunrays Fall on Earth?

• Sunrays travel straight, but because the Earth is round, they fall differently on different areas.
• Some places get direct sunrays, while others get slanting sunrays.

Types of Sunrays:

1. Direct Sunrays → Cover less area, bring more heat (Near the Equator).
2. Slanting Sunrays → Cover larger area, bring less heat (Near the Poles).

Effect on Temperature:

• Near the Equator (Torrid Zone) → Hot because sunrays are direct.
• Between 23.5° and 66.5° (Temperate Zone) → Moderate temperature.
• Near the Poles (Frigid Zone) → Cold because sunrays are slanting.

3. Factors Affecting Temperature

Apart from latitude, other factors also affect temperature:

1. Altitude (Height above sea level)

• Higher places (like mountains) are colder than lower places (like plains).
• Example: Shimla is colder than Delhi because it is on a mountain.

2. Distance from the Sea

• Near the sea → Climate is moderate (less difference between day and night temperature).
• Far from the sea → Climate is extreme (hotter in summer, colder in winter).
• Example: Mumbai (coastal) has moderate climate, but Nagpur (inland) has extreme climate.

3. Land and Water Heating

• Land heats up and cools down quickly, but water heats up and cools down slowly.
• This creates differences in temperature between land and sea.

4. Winds and Ocean Currents

• Warm winds make the area hot, and cold winds make it cool.
• Ocean currents carry warm or cold water, changing the temperature of coastal areas.

4. Temperature Zones of the Earth

The Earth is divided into three temperature zones based on sunrays:

1. Torrid Zone (Hot Zone)

• Between 0° and 23.5° (Equator to Tropics).
• Very hot due to direct sunrays.

2. Temperate Zone (Moderate Zone)

• Between 23.5° and 66.5° (Tropics to Arctic/Antarctic Circles).
• Mild climate, not too hot or too cold.

3. Frigid Zone (Cold Zone)

• Between 66.5° and 90° (Poles).
• Very cold due to slanting sunrays.

5. What is an Isotherm?

• An isotherm is a line on a map that connects places with the same temperature.
• It helps in studying global temperature distribution.

6. What is a Thermometer?

• A thermometer is used to measure temperature.
• It contains mercury or alcohol, which rises or falls based on heat.
• Temperature is measured in degrees Celsius (°C) or Fahrenheit (°F).

7. Difference Between Coastal and Inland Climate

8. How Do Land and Water Affect Temperature?

• Land heats up quickly and cools down quickly.
• Water heats up slowly and cools down slowly.
• This is why coastal areas have a more stable climate, while inland areas have extreme temperatures.

9. How Do Ocean Currents Affect Climate?

• Warm currents make nearby lands warmer (Example: Gulf Stream warms Europe).
• Cold currents make nearby lands colder (Example: Labrador Current cools Canada).
• Fishing is good where warm and cold currents meet (Example: Japan and North America coasts).

10. Global Warming and Greenhouse Gases

• Greenhouse gases (CO₂, water vapor, methane) trap heat in the atmosphere.
• This causes global warming, increasing Earth’s temperature.
• Effects: Melting ice, rising sea levels, extreme weather changes.