Q.Western disturbances are generally observed as a favourable beneficial phenomenon. Comment
Approach
- Start the answer by defining the western disturbances.
- Discuss the impact of western disturbances on the Indian weather systems.
- Conclude suitably.
Introduction
Western Disturbances are low-pressure depressions that occur during winters, particularly in northern India. They are the extratropical storms that originate in the Mediterranean region and bring sudden winter rain and snow to the north-western parts of the Indian subcontinent.
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A western disturbance is an extratropical storm originating in the Mediterranean region that brings sudden winter rain to the northern parts of the Indian subcontinent. It is a non-monsoonal precipitation pattern driven by the westerlies. The moisture in these storms usually originates over the Mediterranean Sea, the Caspian Sea and the Black Sea . Extratropical storms are a global phenomenon with moisture usually carried in the upper atmosphere, unlike their tropical counterparts where the moisture is carried in the lower atmosphere. In the case of the Indian subcontinent, moisture is sometimes shed as rain when the storm system encounters the Himalayas . western disturbances are more frequent and stronger in winter season. |
Body
Impact of western disturbances on the Indian weather systems:
- Western disturbances are estimated to bring 5-10% of India’s total annual rainfall. They are the cause of the most winter and pre-monsoon season rainfall across North-West India.
- Western disturbances are usually associated with a cloudy sky, higher night temperatures, and unusual rain.
- Wheat is one of the most important crops, which helps to meet India’s food security. Western disturbances precipitation has great importance in the growth of wheat and other Rabi crops.
- However, strong western disturbances bring excessive precipitation that can cause crop damage, landslides, floods, and avalanches.
- On the other hand, weak western disturbances are associated with crop failure and water problems across north India.
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A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and/or squalls. |
Conclusion
Western disturbances are generally observed as a favorable beneficial phenomenon. However, owing to climate change, they have caused disasters in the form of cloud bursts and hailstorms.
