1. What is the difference between weather and climate?
Answer:
- Weather refers to the short-term atmospheric conditions like temperature, humidity, rainfall, and wind in a particular place at a specific time.
- Climate is the average weather condition of a place over a long period (typically 30 years or more).
2. What are the major controls of the climate of any place?
Answer: The major controls of climate are:
- Latitude
- Altitude
- Pressure and wind system
- Distance from the sea (continentality)
- Ocean currents
- Relief features (like mountains)
3. Why does India have a monsoon type of climate?
Answer: India has a monsoon type of climate because:
- It lies in the tropical zone and is greatly influenced by the monsoon winds.
- These winds change direction seasonally, leading to seasonal rainfall and variations in temperature.
4. What are the six major controls of the climate of India?
Answer: The six major controls are:
- Latitude
- Altitude
- Pressure and Wind System
- Distance from the sea
- Ocean currents
- Relief features
5. Name the elements of climate and weather.
Answer: The major elements are:
- Temperature
- Atmospheric pressure
- Wind
- Humidity
- Precipitation
6. What is meant by the monsoon?
Answer: The term monsoon is derived from the Arabic word ‘mausim’, meaning season. It refers to the seasonal reversal in the direction of winds, bringing rainfall to India during summer.
7. What are the characteristics of the Indian monsoon?
Answer:
- Seasonal reversal of winds
- Uneven distribution of rainfall
- Orographic rainfall is common
- Sudden onset and withdrawal
- Breaks in rainfall
8. What are the four main seasons in India according to the Indian Meteorological Department (IMD)?
Answer:
- Cold Weather Season (Winter) – December to February
- Hot Weather Season (Summer) – March to May
- Advancing Monsoon Season – June to September
- Retreating Monsoon Season – October to November
9. What causes the retreating of the monsoon?
Answer:
- The low-pressure area weakens as the sun moves southwards.
- Winds start withdrawing from northern India.
- High pressure begins to build in the north, pushing away the moisture-laden winds.
10. What is meant by ‘burst’ of the monsoon?
Answer: The term refers to the sudden onset of the monsoon, often with violent thunderstorms and heavy rainfall, after a long dry spell.
11. Why does Tamil Nadu receive rainfall in winters?
Answer: Tamil Nadu receives rainfall from the North-East monsoon winds, which pick up moisture from the Bay of Bengal and bring rain during October–November.
12. What is the role of Himalayas in India’s climate?
Answer:
- Blocks the cold winds from Central Asia
- Helps retain monsoon winds, causing widespread rainfall
- Influences climate variation in the northern plains
13. Define ‘rain shadow area’ with an example.
Answer: A rain shadow area is a region on the leeward side of a mountain that receives very little rainfall due to descending dry winds.
Example: The Deccan Plateau lies in the rain shadow of the Western Ghats.
14. How does altitude affect the climate of a place?
Answer:
- Temperature decreases with increase in altitude.
- Places at higher altitudes are cooler even if located in the tropical zone (e.g., Shimla is cooler than Delhi).
15. How does the distance from the sea affect climate?
Answer:
- Coastal areas have moderate climate due to the influence of sea.
- Interior areas have extreme or continental climate.
16. Explain the term ‘Jet Stream’. How does it affect Indian climate?
Answer:
- Jet Streams are high-altitude, fast-moving air currents in the upper atmosphere.
- The westerly jet stream influences western disturbances in North India during winter.
- The subtropical jet stream affects the onset of the southwest monsoon.
17. What are western disturbances?
Answer:
- Western disturbances are moisture-laden winds from the Mediterranean Sea.
- They bring winter rainfall in north and northwest India, beneficial for rabi crops.
18. What is the ITCZ?
Answer: ITCZ stands for Inter-Tropical Convergence Zone.
- It is a low-pressure zone near the equator where northeast and southeast trade winds converge.
- Plays a key role in the formation of monsoon winds.
19. What are the local winds and how do they affect the climate?
Answer:
- Local winds are winds that blow over a small area.
- Example: Loo – hot, dry wind blowing over North India in summer, causes heatwaves.
20. What is El Niño and how does it affect Indian climate?
Answer:
- El Niño is a climate phenomenon associated with the warming of the central and eastern Pacific Ocean.
- It weakens the monsoon winds, often leading to droughts in India.