The Union Ministry of Earth Sciences approved an X-band radar to be installed in Kerala’s Wayanad district.
- The decision came after devastating floods and landslides killed more than 200 people in Wayanad n July 2024.
- A torrential downpour triggered the landslide in the valley above Punchirimattom, near the Mundakkai region.
About Radar
- Radar is short for ‘radio detection and ranging’. The device uses radio waves to determine the distance, velocity, and physical characteristics of objects around the device.
Doppler radar
- Doppler radar (Weather radar) is a common application of this device.
- Doppler radars can reveal how fast a cloud is moving and in which direction based on how the cloud’s relative motion changes the frequency of the radiation striking it.
- Modern Doppler radars can monitor weather conditions and anticipate new wind patterns, the formation of storms, etc.
- A pulse-Doppler radar can measure the intensity of, say, rainfall by emitting radiation in pulses and tracking how often they’re reflected to the receiver.
- Doppler radar relies on Rayleigh scattering, when the scatterer is much smaller than the wavelength of the radiation.
- A radar trying to see smaller particles like rain droplets or fog will need to use radiation of lower wavelengths, like in the X-band. The smaller wavelengths allow the radar to produce images of higher resolution. However, the greater the frequency of some radiation, the faster it will be attenuated.
X-band radars
- X-band radars have a relatively shorter range. In Wayanad, the new radar is expected to be able to monitor the movements of particles, such as soil, to inform landslide warnings.
- 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.
(Source: The Hindu)
