Factors that are Affecting the Indian Climate:
1. Affect of Latitude on Indian climate:
- India is situated in the Asian continent. In this continent, India is situated between 37°6′ N to 8°4′ N Latitude. Besides this, the Tropic of Cancer which is 23°5′ N goes through the middle of India and divide this country almost into two equal part. As a result, the northern part of India lies in Temperate Zone. This zone receives less solar radiation. But the summer season of North India is very hot (except in the Himalayan region) due to the local hot wind, called “Loo”.
- On the other hand, winter in north India is cold, due to the cold wave, that comes from the Mediterranean sea. It is known as “Western Disturbance”.
- The southern part of India (south of the tropic of cancer) lies in Tropic Zone. This zone receives more solar radiation than northern India. The summer season of India is hot and the winter season is moderate.
- Although the Indian tropic zone is situated in the high longitude as well as near the sea (the Arabian Sea in the west and the Bay of Bengal in the east), here temperature is comparatively moderate during the summer season.
2. Affect of the Sea on Indian climate:
- India is surrounded by the Arabian Sea at the west, the Indian Ocean in the south, and the Bay Of Bengal in the east. Many metropolitan cities such as Kolkata, Mumbai, Chennai, Kanyakumari, Goa, etc. are situated near the seaside. So, in these cities, winter and summer seasons are not felt so clearly. As a result, the climate of those cities is moderate. On the other hand, the presence of the sea has conducive to rainfall. Owing to the surrounding of the sea from the three sides, southwestern and north-eastern monsoons is carried out huge water vapour from the sea. It causes 90% of rainfall in India.
- Many regions in north India, such as Jaipur, Delhi, Amritsar, etc. are situated far from the coastal area. So the climate of those regions is extreme, which means, the summer season is very hot and the winter season is very cold.
3. Affect of Longitude on Indian Climate:
- Temperature is decreased by 6.4° C at an altitude of one kilometre each from above sea level. It means, there is an inverse relationship between temperature and longitude.
- On account of this reason, temperature exists in high mountainous regions (such as Lahaul-Spiti region, Kedarnath, Badrinath, Rohtang, Amarnath region, etc.) are always below 10°C.
- In winter, the temperature in this region drops below the freezing point(-1°C to – 40°C). Besides, Darjeeling, Shillong, etc. hilly cities of India are located at high altitudes, for this reason, winter is felt here throughout the year.
4. Affect of Mountains on the Indian climate:
- The Himalayan mountain range has been protecting the Indian subcontinent from the bone-chilling winter of Asia. Without the Himalayas, India would have experienced severe winters like Russia and China.
- The various mountains of India have a profound effect on monsoon rainfall.
- Such monsoon winds blowing over the Arabian Sea, obstruct the Western Ghats and causes heavy rainfall (380 – 500 cm) on the western slopes states (Maharashtra, Goa, Kerala, Karnataka) of the Western Ghats.
- After heavy rainfall in the Western Ghats, It flows over the Deccan Plateau and Madhya Pradesh. Then it has fewer water drops, So the rainfall occurs less (60 to 65 cm). That is why the western part of the Western Ghats is called the rain feed region.
- The monsoon winds of the Bay of Bengal branch, reach the Khasi hills of Meghalaya and rise very high. Here the cold monsoon wind is condensed and caused heavy rainfall on the southern slopes of the Khasi hills at Cherrapunji and Mawsynram.
5. Affect of Monsoon Wind on Indian Climate:
- The winter season in India is dry and the summer season is moist due to the monsoon wind.
- In the summer season, the monsoon wind blows from the southwest direction. Whereas in the winter season, it blows from the northeast direction.
- In India, the rainfall due to the Monsoon is uncertain. Sometimes floods occur due to heavy rains and sometimes drought occurs due to the lack of rainfall.
- India gets maximum rainfall from June to September due to monsoon wind. Almost 90% of rainfall in India happens due to monsoon wind. Almost 60% of the agricultural land area of India depends on this rainfall.
Also, Read El Nino and La Nino
6. Affect of El Nino on Indian Climate:
- El-Nino is a Spanish word it means “Bad Boy”. El Nino is occasionally seen on the Peru Coast in the south Pacific Ocean. It is an unusual south-facing warm ocean current (Equatorial Current).
- It is seen every four or seven years of concealment. During the El Nino years, heavy rainfall or several droughts have been seen in different parts of India as well as in the world.
7. Affect of La-Nino on Indian Climate:
- It is also a Spanish word. Basically, it is a female counterpart of El Nino. This word is used to identify the southern oscillation of El-Nino or the cold ocean current of lower latitudes in the Pacific Ocean. It is a very powerful Trade Wind. It occurs every 3/7 years of concealment.
8. Affect of Jet Steam:
- It is a flow of wind in the Troposphere. It blows at 9 km above sea level. Its average speed is 160 km per hour to 900 km per hour.
- Mainly two branches of the Jet stream affect on Indian Climate. That is an easterly jet stream and a westerly jet stream. Tropical easterly jet stream flows over the Indian subcontinent. It creates a very low pressure thereby pulling up the surface of the air. To feel up the low-pressure wind from the high-pressure area of the Arabian Sea begins to flow in the northeast direction known as South-west Monsoon.
- Due to the westerly jet stream, temperate storms hit on northwest India which is known as a western disturbance. Almost 3 to 5 cyclonic weaves hit this region from October to April. Although western disturbances give occasional rainfall which is very beneficial for Rabi crops.
9. Affect of Tropical Cyclone
- It originates in the Bay of Bengal as well as in the Arabian Sea. Tropical cyclone impacts the larger parts of the Indian peninsular region.
- Most cyclones originate in the Bay of Bengal. During the southwest monsoon season, tropical cyclones influence the weather conditions in the coastal areas. These cyclones are low-intensity in nature.
- Sometimes cyclones are born during the time of the retreating monsoon season, in October and November. These types of cyclones are high-intensity cyclones. It impacts the weather conditions along the eastern coast of India.