Continuous operation of S-Band Doppler Weather Radar restored

One more radar will soon be added at Kalpakkam: Mohapatra, Director General of Meteorology

The existing S band radar, which will continuously monitor weather up to 400-km radius, was renovated as the procurement process for the new one will take three or four years

The operation of S-band doppler weather radar (DWR) on Rajaji Salai, the first to be indigenously renovated, was restored on Saturday after many challenges.

Noting that Tamil Nadu was given top priority in improving the weather observational network, M.Mohapatra, Director General of Meteorology, India Meteorological Department said another S-band radar would be set up at Kalpakkam by the Department of Atomic Energy. The department already gets weather data from radars on Rajaji Salai, NIOT Pallikaranai, and in Karaikal and Sriharikota.

There are also plans to install another radar for Chennai at another location in a few years’ time. The existing S-band radar, which would continuously monitor weather up to 400-km radius, was renovated as the procurement process for the new one would take three or four years, he said in a press briefing after the inauguration ceremony.

IMD also allocated 10-15 automatic rain gauges for the State and suitable sites were being identified to create a denser observational network. There are plans to develop city-specific ARG networks and also strengthen the existing network, said Mr.Mohapatra.

Mausam, IMD’s mobile application for weather warnings and information would soon be made available in regional languages too. Underlining the IMD’s concerted efforts to provide precise weather predictions and adopt new technology, he said the loss of lives reduced significantly due to cyclones than in the 1960s. The accuracy of weather predictions, particularly heavy rain warning, has improved to 75-80% now compared to 65% accuracy five years ago.

IMD plans to improve the accuracy of heavy rain warning up to 90-95% by 2030 and also run higher resolution models that could predict weather events within a range of six km in the next two or three years.

On the S-band DWR, S.Balachandran, Deputy Director General of Meteorology, Chennai, said it was the first DWR installed in the country in 2002 and its continuous operation was restricted due to ageing and technical snag in antenna bull gear unit. Radar is part of the range of observational network, including satellite and pilot balloons.

Elaborating on the challenges in renovating the DWR, B.Arul Malar Kannan, in charge of DWR, said the initial repairs was detected in 2018 and corrective measures were taken even as communications were exchanged with a German firm that made the spare parts. However, there were difficulties in replacing spare parts as the manufacturing time was more, technology had changed and delay due to COVID-19 pandemic. Restricted operation of the radar was carried out till 2021.

With the technical support of ISRO, new bull gear unit was designed and fabricated in the country. V.K.Anandan, ISTRAC, ISRO, Bangalore, said Chennai-based Shanthi Engineering and Karthik Engineering were engaged for restoration of radar. Its lifespan has been increased by a decade.

V.Thiruppugazh, head, advisory committee for flood risk mitigation and management in CMA, spoke on IMD’s role in reducing fatalities during natural disasters with its precise weather warnings.