Wayanad’s New X-Band Radar: Enhancing Weather Monitoring and Forecasting in India
- October 14, 2024
- Posted by: OptimizeIAS Team
- Category: DPN Topics
Wayanad’s New X-Band Radar: Enhancing Weather Monitoring and Forecasting in India
Sub : Geo
Sec : Climatology
Why in News
In July 2024, heavy rainfall led to devastating floods and landslides in Kerala’s Wayanad district, causing over 200 fatalities. To improve disaster preparedness and early warning systems, the Union Ministry of Earth Sciences approved the installation of an X-band radar in Wayanad to monitor weather conditions and soil movements, which are crucial for landslide detection.
What is RADAR?
RADAR is the expansion for Radio, Detection and Ranging.
Its basic components are a transmitter, receiver, antenna, power supply system, signal processing and high computing devices.
It works on the principle of electromagnetic waves sent out by the transmitter.
The same wave that strikes an object/dense medium is reflected back to the receiver.
The distance up to the object is determined based on the speed of the electromagnetic wave, and the time to travel to the object and back.
There are at least ten types of radars.
Ground Penetrating Radar: It studies the Earth’s crust up to 9-metre in depth.
It is being used by the Defence Geoinformatics Research Establishment (DGRE) at Joshimath.
InSAR (Interferometric Synthetic Aperture Radar)
It makes high-density measurements over large areas by using radar signals from Earth-orbiting satellites and measures changes in land surface.
It is also being used in Joshimath and other parts of Uttarakhand.
History of Radar Use in India: India began using radar for meteorological purposes in the 1950s.
The first indigenously designed X-band radar was installed in 1970 in New Delhi.
In the 1990s, the Indian Meteorological Department (IMD) upgraded outdated X-band radars with digital systems. India uses both X-band and S-band radars for weather detection, with the S-band radar being preferred for long-range cyclone detection.
Expansion of Radar Infrastructure: In September 2024, the Union Cabinet approved a ₹2,000-crore ‘Mission Mausam’, aiming to install up to 60 new meteorological radars by 2026, enhancing weather forecasting capabilities.
Doppler radar:
A Doppler Radar is a specialised radar that uses the Doppler effect to produce velocity data about objects at a distance.
- When the source and the signal are in relative motion to each other, there is a change in the frequency observed by the observer. This is called the Doppler effect.
- If they are moving closer, the frequency increases and vice versa.
A Doppler Weather Radar (DWR) works on the Doppler principle.
- It is designed to improve precision in long-range weather forecasting and surveillance using a parabolic dish antenna and a foam sandwich spherical radome.
DWR has the equipment to measure rainfall intensity, wind shear and velocity and locate a storm centre and the direction of a tornado or gust front.
Why DWR is considered superior to other radars?
Unlike others, a DWR has the ability to detect air motion, wind, speed of wind, rains, temperature, thunderstorms, hail, squalls, lightning, cyclones and cloud movements and volumetric analysis of cloud and reflectivity index, among others.
It costs approximately ₹10-20 crore per unit.
The National Ocean and Atmospheric Administration (NOAA) of the US uses 148 of them.
The Indian Army and Air Force have deployed the Indian Doppler Radar (INDRA) for the detection of aircraft and other objects in the air.
What is an X-Band Radar?
An X-band radar operates in the 8-12 GHz frequency range (wavelengths of 2-4 cm). This shorter wavelength allows for high-resolution imagery, making it ideal for detecting smaller objects such as rain droplets and fog. However, because higher frequencies attenuate more quickly, X-band radars have a shorter range compared to lower-frequency radars.
Why Does Wayanad Need an X-Band Radar?
Wayanad is prone to landslides and floods, as demonstrated by the July 2024 disaster. The X-band radar will play a crucial role in monitoring soil and particle movements, providing early warnings for landslides, and improving overall disaster preparedness in the region. Additionally, the radar will complement existing weather forecasting infrastructure by providing localized, high-resolution data.
NISAR: A Joint Initiative by NASA and ISRO
The NASA-ISRO Synthetic Aperture Radar (NISAR) is a satellite designed to monitor Earth’s land masses using radar imaging. Its payload will consist of an L-band radar built by NASA and an S-band radar developed by ISRO. The satellite will track and provide data on natural processes, including soil displacement, landslides, and changes in vegetation.
The NISAR satellite is set to launch in 2025 on an ISRO GSLV Mk II rocket, with an estimated cost of $1.5 billion, largely funded by NASA. This satellite will contribute to global environmental monitoring efforts and disaster management.
The U.S. will contribute the large deployable antenna.
It is a dual band polarisable radar.
Benefits of NISAR:
- It has a large deployable antenna with an 18-meter diameter, it has a very high swath.
- It can fully cover the earth in approximately 14 to 15 days, in radar. It can monitor various aspects in very high resolution.
- It can monitor the tectonic movements to centimetre accuracy.
- It can accurately measure water bodies.
- It can look at water stressing on the earth, wherever there is deficiency of water.
- It can ground-penetrate to a certain depth. It is capable of monitoring the vegetation cover and snow cover