‘We’re very good at up to five days’ forecast, but we continue to fail in Delhi’

New Delhi, July 11 (SocialNews.XYZ) The cat is out of the bag!

M. Ravichandran, Secretary in the Ministry of Earth Sciences (MoES), under which the India Meteorological Department (IMD) is the premier weather forecasting agency, accepted on Monday that while the IMD is very good at up to five days' forecast over large areas, it continues to fail when it comes to Delhi, and suggested that the national capital needs more and more drone-based observations.

The IMD has been regularly receiving flak for not getting forecasts for Delhi correct -- be it the onset of monsoon over Delhi-NCR, or the rainfall pattern (or earlier in summer, the heat wave timings). Last week, monsoon had gone missing from the national capital since July 2. From Monday onwards, it was a case of hide and seek between the IMD forecast and rains. Finally, Delhi-NCR received rain on Monday (July 11).

Speaking with reporters, Ravichandran explained why the IMD has been failing in its forecast when it comes to Delhi.

"Delhi-NCR is the location for convergence of two regimes, the easterlies as well as the low pressure area from Bay of Bengal. We are at the border of the trough. Even the large-scale scenario is conducive but the local things are changing. That characterisation of various regimes still needs to evolve," he said, adding, "We can only forecast cloud. Here, there are clouds but there is no precipitation. In the hilly region, it will definitely rain in this condition. In the coastal areas, it will be different. In Delhi, it will be different."

To a question if there is a need for more instruments or more science, Ravichandran said, "Actually we need more science, but for more science we need instruments. Instruments serve two purposes. Some instruments are needed to understand the phenomenon, so observation is required. More high frequency observations are required to understand the process."

The IMD needs more observations to know what is going on in the atmosphere. Then, those observations are put in the forecast models and then further input is received from that model.

"So, basically high-frequency observation is required and also cloud dynamics," he said.

More number of observations is needed to be assimilated into the forecast models, for which, there is not enough of observational network, therefore, suggesting that Delhi should have more and more drone-based observational systems.

"We are experimenting with drone based observations, at least for two kms. We need three parameters - temperature, humidity and wind," Ravichandran said.

Source: IANS