Mains Practice Questions

Introduction

Western Disturbances(WD) are extra-tropical storm systems that originate in the Mediterranean region and travel eastward, bringing sudden winter rain and snow to the northwestern parts of the Indian subcontinent.

Body

Formation and Characteristics:

• Origin: WDs typically form over the Mediterranean Sea or Atlantic Ocean during the winter and early spring seasons.
• Movement: These systems move eastward across Europe and Central Asia, eventually reaching the Indian subcontinent.
• Characteristics: WDs are characterised by their low-pressure centres, associated fronts (warm and cold), and precipitation.
  • They often bring significant rainfall, snowfall, and changes in temperature to the regions they pass over.

Impact on North India's Weather:

• Winter Rainfall: WDs are the primary source of winter rainfall in North India, particularly in the northwestern regions of Punjab, Haryana, and Jammu and Kashmir.
  • The precipitation brought by WDs is essential for agriculture and replenishing groundwater levels.
• Temperature Fluctuations: The passage of WDs can lead to significant fluctuations in temperature.
  • Cold air masses associated with WDs can cause a sudden drop in temperature, leading to chilly weather conditions.
    • Conversely, the warm sector of a WD can bring milder temperatures.
• Snowfall: In the higher reaches of the Himalayas, WDs can bring snowfall, which is crucial for maintaining snow cover in the glaciers and rivers.
  • This snowmelt plays a vital role in irrigation and hydropower generation.
• Agricultural Impact: WDs are beneficial for agriculture in North India, as they provide much-needed moisture for crops.
  • However, excessive rainfall or untimely snowfall can also cause damage to crops.
    • In 2019, due to Western Disturbances, the mustard crop was affected in Haryana, and it damaged the potato crop in Punjab.

Conclusion

Western Disturbances play a crucial role in shaping the weather patterns of North India, particularly during the winter months. Their impact extends beyond meteorology, affecting agriculture, water resources, and the overall economy of the region.