Context

A research testbed facility has been proposed to help meteorologists to deploy drones, mobile vans and high-end instruments to track the Nor’westers, or Kalbaisakhi, that affect the east and northeast regions of India every summer.

• Norwesters Impact: Though the Norwesters were less active this summer, there were occasional instances in April and early May. 
  • Strong winds and thunderstorms swept through the northern districts of West Bengal, Assam and Tripura, killing at least five people last month.

Enroll now for UPSC Online Course

Research Testbed Facility to Study Norwesters

• About: The proposed facility will cover a large area adjoining West Bengal, Odisha, and Jharkhand. 
  • The control centre will be at Chandbali in the Bhadrak district of Odisha, about 130 km east of Bhubaneswar.
• Development: India Meteorological Department (IMD), Indian Institute of Tropical Meteorology (IITM), Pune, and National Centre for Medium-Range Weather Forecasting (NCMRWF), Delhi, will jointly develop and use this facility.
  • Minister of Earth Sciences, stated that the facility will be completed by 2026.
• Aim: It aims to study thunderstorms from the formation stage, growth, and propagation over eastern parts of the country. 
  • This will be done using meteorological instruments, drones, and other equipment that will aid in systematically tracking thunderstorms.
  • IMD, Pune, will collate all the data generated from the testbed facility for further research and analysis.
• Complementing Existing Mechanisms: It will house several high-end instruments complementing the existing observational mechanisms.
  • The eastern India region is currently covered by meteorological radars supported by a network of instruments to record upper air and surface observations.
• Significance: The large volumes of data generated from the facility are expected to help forecasters make timely thunderstorm predictions, issue nowcast warnings (an event in less than three hours), and ultimately save lives.
  • This can help make better predictions and generate early warning mechanisms to save lives and property.
• Improved Lead Times for Extreme Weather Events: The IMD currently issues nowcast warnings for extreme weather events with a lead time of three hours. 
  • With the establishment of the first dedicated testbed for thunderstorms, the goal is to provide warnings with improved lead times and to map the areas likely to be most affected. 
  • This will give the administration and local communities more time to prepare and respond effectively.

About Norwesters

• About: Originating over east and northeast India, south Nepal, Bhutan and Bangladesh, the norwesters are extremely severe thunderstorms accompanied by squally winds. 
  • These storms usually travel from northwest to southeast direction locally known as“Kalbaisakhi” and  “Barodoli Cheerha” in Assam. 
  • A squall is a sudden, sharp increase in wind speed lasting minutes, as opposed to a wind gust, which lasts for only seconds. 
• Impact:  It brings destruction in terms of lightning, thunderstorms, hailstorms and rainfall. It is beneficial for pre-Kharif crops such as paddy, jute, and many other fruits and vegetables. 
• Need for In-depth Study of Norwesters’ Genesis and Processes: Norwesters are severe thunderstorms that need further investigation with respect to its genesis at the micro level and other processes involved. 

Mechanism:

• Heating Induced Convection:  In the early summer months (March and April), the daytime landmass heating over these regions triggers convection over some areas of Bihar, Jharkhand, Chhattisgarh, Odisha, and sub-Himalayan West Bengal.
• Interaction with Warm, Moist Air Masses Over the Bay of Bengal: As these convective clouds move towards West Bengal and Bangladesh, the norwesters mix with the warm, moist air mass persistent over the Bay of Bengal, causing significant wind discontinuity. 
• Ideal Conditions for Thunderstorm Development: The local hills, thick forest cover, and the sea breeze make it ideal for developing thunderstorm cloud cells. 
• These thunderstorm events usually prevail between two to four hours during late afternoon hours.

Enroll now for UPSC Online Classes

DOWNLOAD PDF