Class 6 Science Chapter-7 Question Answer

1. Definition of Weather:

• Weather refers to the day-to-day state or condition of the atmosphere at a particular place with respect to temperature, humidity, rainfall, wind speed, and direction.   
• It is a complex phenomenon that can change rapidly over very short periods, such as from day to day or week to week.   

2. Elements of Weather and Measuring Instruments:

• Temperature (Maximum and Minimum): Measured using a thermometer.   
• Rainfall: Measured using a rain gauge.   
• Wind Direction: Indicated using a wind vane.   
• Wind Speed: Measured using an anemometer.   
• Air Pressure: Measured using a barometer.   
• Humidity: Represents the amount of water vapor present in the atmosphere.   

3. Definition of Climate:

• Climate represents the long-term pattern, or average weather conditions, recorded over a long period (typically 25 to 30 years or more) for a specific region.   
• For example, the climate of the Rajasthan desert is hot and dry, whereas the climate of Jammu and Kashmir is extremely cold.   

4. Global Climatic Zones and Sun’s Role:

• All weather and climatic patterns on Earth are driven primarily by energy from the Sun.   
• Equatorial / Tropical Zone: Located between the Tropic of Cancer and the Tropic of Capricorn. It receives direct, intense sunlight, resulting in high heat and heavy rainfall.   
• Polar Regions (North and South Poles): Extremely cold and covered with snow. The Sun does not set for 6 months and does not rise for the other 6 months of the year.   
• Temperate Zone: Experiences moderate climate (neither extremely hot nor extremely cold) with clear seasonal cycles (summer, autumn, winter, and monsoon).

5. Factors Affecting Climate:

• The climate of a region depends on its height above sea level (altitude), terrain/relief, and distance from the sea.   

6. Climate and Agriculture in Assam:

• Assam experiences a tropical monsoon rainy climate characterized by high humidity and moderate temperatures.   
• Kharif Crops: Grown during the summer and rainy season due to high temperatures and heavy rain brought by the southwest monsoon winds (e.g., paddy/rice and jute).   
• Rabi Crops: Sown at the beginning of autumn/winter because they require cooler temperatures and less water (e.g., wheat, mustard, chickpeas/pulses, potatoes, and spinach).   

7. Climate Change and Environmental Impacts:

• Atmospheric temperatures are steadily rising due to greenhouse gas emissions caused by the excessive burning of fossil fuels, industrial activities, and domestic electrical appliances.   

 Major Consequences:

• Melting of polar ice and glaciers.   
• Rising sea levels and coastal flooding.   
• Increased frequency of severe droughts, causing agricultural soil to crack and leading to crop shortages.   
• Frequent dust storms, forest fires, intense heatwaves, and loss of wildlife habitats.   

Mitigating climate change requires collective awareness, sustainable living practices, and environmentally responsible human activities.