Kerala to soon have 218 rainfall observatories

Work to be completed before December this year: IMD

In order to be better equipped against extreme rainfall events and its localised spatial distribution, a key challenge Kerala faces, the State will soon have 218 rainfall monitoring observatories, including automatic and manual, against the required 115 as mandated by the Bureau of Indian Standard (BIS)-1994.

In reply to a question in Parliament recently, Jitendra Singh, Union Minister of State (Independent Charge) for Science and Technology and Earth Sciences, said there had been a request for installation of 100 more Automatic Weather Stations (AWS) in Kerala, out of which 15 AWS have already been installed. Work is under way for the installation of the remaining 85, which will take the number of observatories for rainfall monitoring in the State to 218.

Sources in the India Meteorological Department (IMD) said the work is to be completed before December this year. But with the current pace of work, officials are hopeful of installing the AWS before the next monsoon season. The State already has 133 observatories, including 63 functional automatic stations – 30 AWS, three Agro AWS and 30 automatic rain gauges (ARG) – to record rainfall, in addition to the 70 manual observatories.

However, a document published by the BIS in 1994 on the number of non-recording/recording rain gauges per sq km computed that the State requires 63 rain stations for coastal and plain lands, which account for 80% of the total area of the State, whereas the hilly terrain requires 52 rain stations. Hence, 115 rain stations are required for the State as per the BIS.

Speaking to The Hindu, K Santhosh, Director, IMD, Thiruvananthapuram, said: “with 218 rainfall monitoring observatories, the State will receive more localised data on weather parameters such as wind speed and pressure, temperature, atmospheric pressure and rainfall in short intervals. This would help the IMD assess the quality of the forecast through forecast verification. Moreover, the State now requires more such weather stations considering the frequency and intensity of rainfall or temperature being recorded,” said Mr. Santhosh.

A mix of both manual and automatic would do well for the State as chances for error could not be ruled out in automatic stations in the event of technical glitches, while the chances for error are relatively low in manual stations, said officials.