48 hrs early prediction of Uttarakhand-like cloud-burst by 2022, says report
India will be able to forecast extreme weather events like ‘cloud bursts’ at least two days in advance from 2022, the ministry of earth sciences (MoES) has informed a parliamentary committee.
“The ministry (MoES) stated that unlike cyclones, forecasting a cloudburst is very difficult due to the dynamics of the rapidly developing clouds over a very small area. However, they could make a probabilistic forecast on the possibility of cloudburst events over a specific area 48 hours in advance with an enhanced computing facility,” the parliamentary committee stated in its report submitted to the Rajya Sabha earlier this month.
Cloud bursts are extreme weather events in which an area registers more than 100 mm rain in just one hour. The Uttarakhand flood of June 2013 triggered by cloud bursts killed a few thousand people and many more were reported missing apart from causing a massive loss to property and infrastructure.
At present India’s weather forecasting system depends on high-performance computing (HPC) system with a capacity of 10 PetaFlops. Plans are, however, afoot to augment the current HPC from 10 PFlops to 40 PFlops by 2022 and to 100 PFlops by 2024.
“With the facility being upgraded, we will be able to forecast extreme weather events such as cloud bursts at least two days in advance by 2022. Also at present, our forecasts have a resolution with a precision up to 12 km. With such advanced computing system we will be able to give forecast up to 5 km, or maybe even up to 3 km, with far more detailed predictions,” said Madhavan Nair Rajeevan, secretary of MoES.
Experts said that this will allow authorities a period of at least two days to initiate pre-emptive actions to save lives and property. At present cloudbursts are predicted two to three hours in advance in terms of heavy rainfall using Doppler Weather Radars and Satellite Data.
“At present science is not the limiting factor. Computing facility is the limiting factor. To forecast extreme events like cloud bursts and very heavy rainfall, highly localized phenomenon, we not only need to increase our horizontal resolution to less than one kilometre but also increase our vertical resolution,” said KJ Ramesh, former director-general of the India Meteorological Department.
“With an upgraded HPC system of 100 PFlops, meteorologists will be able to analyze the fast-changing microphysical characteristics of clouds and better will be our forecast,” he said.
India has witnessed an increase in extreme weather events like extremely heavy rainfall leading to floods, severe heat waves and cyclones in the recent past, the Lok Sabha was told earlier this month. In the changing climate scenario, central and northern India and the western Himalayas have become more prone to extreme rainfall events, whereas north, northwest and neighbouring central India are prone to heat waves. In 2019, at least eight cyclonic storms formed over the Arabian Sea and Bay of Bengal. Usually, five cyclones develop in the Indian seas in a year.