Installation of X-Band Radar | 18 Oct 2024

Source: TH

Why in News?

Recently, the Ministry of Earth Sciences approved an X-band radar to be installed in Kerala’s Wayanad district after devastating floods and landslides. 

What are Key Facts About X-Band Radars? 

• About Radar: Radar is a device that uses radio waves to detect and locate objects by measuring the reflection of the waves.  
  • Radar stands for radio detection and ranging. 
• Working of Radar: The radar device comprises a transmitter that emits a signal aimed at an object whose characteristics are to be ascertained (e.g., cloud in meteorology).  
  • A part of the emitted signal is echoed by the object back to the device, where a receiver tracks and analyses it. 
• Applications in Meteorology: Doppler radars (weather radar) reveal how fast a cloud is moving and in which direction based on the cloud’s relative motion changes the frequency of the radiation striking it. 
  • A Pulse-Doppler radar can measure the intensity of rainfall by emitting radiation in pulses and tracking how often they’re reflected to the receiver. 
  • Doppler effect is the change in frequency of sound waves as their source moves towards and away from a listener.  
  • Doppler radars rely on Rayleigh scattering in which light or other electromagnetic radiation is scattered by particles much smaller than the wavelength of the light. 
  • Modern Doppler radars can monitor weather conditions and anticipate new wind patterns, the formation of storms, etc. 
• X-Band Radar: An X-band radar is radar that emits radiation in the X-band of the electromagnetic spectrum (8-12 GHz) corresponding to wavelengths of around 2-4 cm (this is in the microwave part of the spectrum.) 
  • It uses radiation of lower wavelengths to observe smaller particles like rain droplets or fog. 
  • The smaller wavelengths allow the radar to produce images of higher resolution but X-band radars have a relatively shorter range. 
• Role of X-Band Radar in Wayanad: It will monitor soil particle movements, assisting in the issuance of landslide warnings. 
  • It will conduct high temporal sampling, allowing for rapid detection of changes in particle movement over brief periods. 

How many radars does India have? 

• Historical Context: The India Meteorological Department (IMD) began using radar for weather in the early 1950s.  
  • In 1970, it installed the first indigenously designed X-band storm detection radar in New Delhi. By 1996, IMD upgraded 10 outdated X-band radars to digital versions. 
• Types of Radar Network: In its X-band radar network, India has both wind-finding and storm-detecting radars, and some with dual capabilities.  
  • India also uses S-band radars (2-4 GHz) for long-range detection.  
  • The first S-band cyclone detection radar was installed in Visakhapatnam in 1970 and the first locally made variant was commissioned in Mumbai in 1980.  
• Recent Initiatives: As of September 2024, India plans to install 56 additional Doppler radars, part of the Rs 2,000-crore Mission Mausam initiative aimed at enhancing meteorological infrastructure by 2026. 
  • The government is also in the process of acquiring and installing 10 X-band Doppler radars in northeastern states and Himachal Pradesh’s Lahaul and Spiti district. 
  • A C-band radar (4-8 GHz) with an observational range of 250 km will be installed in Mangaluru.