Radar used to forecast weather was not working when high-velocity dust storm killed over 100 in Rajasthan, UP

New Delhi/Jaipur: The doppler radar in the Jaipur Met office, a critical component in the accurate forecasting of weather events, was not working the night of May 2 when a high velocity dust storm cut a swathe of destruction through parts of Rajasthan, killing at least 35 people, an IMD official said.

The doppler, a product of Finnish company Vaisala, has been dysfunctional for the last 10 days, said Devendra Pradhan, additional director general of the India Meteorological Department. "The doppler radar of Jaipur has been dysfunctional for the last 10 days due to some technical issues. The engineers of Vaisala, a Finnish company, are here. The problem will be rectified in the next two-three days," Pradhan said. Besides doppler radars, the IMD depends on observatories and satellites for accurate weather forecasts. 

A doppler radar helps in better assessment of the severity of a hailstorm, thunderstorms, wind movement and also helps in nowcasts, weather alerts issued for two-three hours, Pradhan explained. "It is an important tool for disaster management," Pradhan, who looks after doppler radars across the country, said. 

Of the 27 IMD doppler radars in the country, two, in Jaipur and Karaikal, are not working, Pradhan said. "We had been issuing alerts since April 29 using our doppler radar from Delhi. Had the Jaipur radar been working, we would have been in a much better position," he said. 

There was a fault in the doppler radar on May 2, which was rectified the next day, said Himanshu Sharma, acting director, IMD Jaipur. "However, we had issued a warning to the relief department about the dust storm that affected three districts of Rajasthan," Sharma added.

More than 100 people were killed as the dust storm whipped through parts of Rajasthan, including Dholpur and Bharatpur, and Uttar Pradesh, bringing down houses, uprooting trees and electricity poles and flattening crops. 

A fresh warning was issued today about a possible thunderstorm accompanied with squall which may hit West Bengal, Odisha, Bihar and Uttar Pradesh, a home ministry spokesperson said. A doppler has a radius of 250 km and the alert issued by the Jaipur IMD today was based on the doppler radar in Delhi, officials said. 

However, several places in the Agra division, where more than 40 people were killed, and areas like Dholpur fall beyond the radius. Dholpur, for instance, is much closer to Jaipur than Delhi. There is a doppler at Lucknow but the dust storm that hit parts of Rajasthan and Uttar Pradesh was beyond its range. 

The importance of doppler radars was felt after the 2005 Mumbai floods, in which hundreds of people were killed, following which the process was fast-tracked.