1. Choose the correct answer from the four alternatives given below.
(i) Which one of the following places receives the highest rainfall in the world?
(a) Silchar
(b) Mawsynram
(c) Cherrapunji
(d) Guwahati
Answer: (b) Mawsynram
(ii) The wind blowing in the northern plains in summers is known as:
(a) Kaal Baisakhi
(b) Loo
(c) Trade Winds
(d) None of the above
Answer: (b) Loo
(iii) Monsoon arrives in India approximately in:
(a) Early May
(b) Early July
(c) Early June
(d) Early August
Answer: (c) Early June
(iv) Which one of the following characterises the cold weather season in India?
(a) Warm days and warm nights
(b) Warm days and cold nights
(c) Cool days and cold nights
(d) Cold days and warm nights
Answer: (c) Cool days and cold nights
2. Answer the following questions briefly.
(i) What are the controls affecting the climate of India?
Answer:
The controls affecting the climate of India are:
- Latitude
- Altitude
- Pressure and wind system
- Distance from the sea
- Ocean currents
- Relief features (like mountains)
(ii) Why does India have a monsoon type of climate?
Answer:
India has a monsoon type of climate because it experiences seasonal winds. The monsoon winds change direction twice a year – bringing rain during summer (Southwest Monsoon) and dry weather during winter (Northeast Monsoon).
(iii) Which part of India experiences the highest diurnal range of temperature and why?
Answer:
The Thar Desert in Rajasthan experiences the highest diurnal range of temperature. During the day, it is very hot, while at night, the temperature drops drastically because there is no moisture to retain heat.
(iv) Which winds account for rainfall along the Malabar coast?
Answer:
The Southwest Monsoon winds account for rainfall along the Malabar coast.
(v) Define monsoons. What do you understand by “break” in monsoon?
Answer:
Monsoons are seasonal winds that reverse direction between summer and winter. A “break” in the monsoon refers to periods of no rainfall during the rainy season. It occurs when the monsoon trough shifts, causing wet and dry spells.
(vi) Why is the monsoon considered a unifying bond?
Answer:
The monsoon is considered a unifying bond because it provides water for agriculture across the country, supporting the lives of millions. The monsoon influences the seasons, festivals, crops, and the daily lives of people, connecting the entire country through its rhythms.
3. Why does the rainfall decrease from the east to the west in Northern India?
Answer:
Rainfall decreases from east to west in Northern India because the monsoon winds lose moisture as they move from the Bay of Bengal towards the interior. The eastern part (like West Bengal and Bihar) receives more rain, while the western part (like Rajasthan) gets less rain as the winds become dry.
4. Give reasons as to why:
(i) Seasonal reversal of wind direction takes place over the Indian subcontinent?
Answer:
Seasonal reversal of wind direction occurs because of the differences in pressure over land and sea. In summer, low pressure forms over the Indian landmass, drawing in moisture-laden winds from the ocean (Southwest Monsoon). In winter, high pressure forms over the land, and dry winds blow from the land to the sea (Northeast Monsoon).
(ii) The bulk of rainfall in India is concentrated over a few months?
Answer:
The bulk of rainfall in India occurs during the monsoon season (June to September) because the Southwest Monsoon winds bring moisture from the Indian Ocean, causing heavy rains in most parts of the country during these months.
(iii) The Tamil Nadu coast receives winter rainfall?
Answer:
The Tamil Nadu coast receives winter rainfall because of the Northeast Monsoon winds, which pick up moisture from the Bay of Bengal and bring rain to the southeastern coast of India during October and November.
(iv) The delta region of the eastern coast is frequently struck by cyclones?
Answer:
The delta region of the eastern coast is frequently struck by cyclones because it is located near the Bay of Bengal, where cyclonic depressions form during the retreating monsoon season (October-November). These cyclones often hit the coastal areas, causing heavy rain and damage.
(v) Parts of Rajasthan, Gujarat, and the leeward side of the Western Ghats are drought-prone?
Answer:
These areas are drought-prone because they receive very little rainfall. Rajasthan and Gujarat are located far from the Bay of Bengal, so the monsoon winds lose most of their moisture before reaching them. The leeward side of the Western Ghats is in the rain shadow region, where the mountains block the rain-bearing winds.
5. Describe the regional variations in the climatic conditions of India with the help of suitable examples.
Answer:
India experiences a wide range of climatic conditions:
- In Rajasthan, temperatures rise to 50°C in summer and drop to near 0°C in winter.
- In Kerala, temperatures remain around 25-30°C throughout the year with heavy rainfall.
- In the Himalayas, places like Drass experience extreme cold in winter with temperatures falling below -45°C.
- In Meghalaya, places like Mawsynram receive over 400 cm of rainfall annually, while Ladakh receives less than 10 cm of rain.
6. Give an account of weather conditions and characteristics of the cold season.
Answer:
The cold season in India lasts from November to February. In northern India, the temperature ranges between 10°C and 15°C. Frost is common, and the higher slopes of the Himalayas experience snowfall. The northeast trade winds blow during this season, bringing dry weather to most parts of the country. However, the Tamil Nadu coast receives some rain from these winds. The northern plains also experience occasional cyclonic disturbances that bring winter rains, important for the rabi crops.
7. Give the characteristics and effects of the monsoon rainfall in India.
Answer:
The monsoon rainfall in India is seasonal, arriving in June and lasting until September. The monsoon winds bring heavy rains to most parts of the country. The western coast and northeastern India receive the heaviest rainfall, while parts of Rajasthan and Gujarat receive little rain. The monsoon has breaks, with periods of rain followed by dry spells. The monsoon is crucial for agriculture, but it can also cause floods in some areas and droughts in others due to its uneven distribution.