The India Meteorological Department (IMD) has launched a dynamic, impact-based cyclone warning system aimed at minimising economic losses and damage to property from cyclones that hit the country’s coasts every year.
Specific warnings will be issued to help prevent economic loss/damage to infrastructure, said Mrutyunjay Mohapatra, Director-General, IMD, while making a presentation at the World Space Week celebrations organised by the Delhi chapter of the Indian Society of Remote Sensing recently.
Warning system goes live
The dynamic, impact-based cyclone warning has been commissioned from this cyclone season (October-December) season even as the IMD is currently tracking the evolution and progress of a deep depression (next only to a cyclone), the first such during post-monsoon, in the Bay of Bengal.
Dissemination of warnings for the vulnerable groups in the last mile along the coast as well those out in the sea would be improved. The Ministry of Earth Sciences is continuously upgrading its plans and strategies in the regard. Lessons learnt from past cyclone events will be used for guidance.
East coast as target
Mohapatra said that the major impact can be seen in the pre- and post-monsoon months known for cyclone genesis. The storms during the month of October to December, particularly in the Bay of Bengal, are known to ravage the country’s eastern coast and damage property.
Until now, the IMD has been giving a warning about the kind of damage that can be expected. But now it would issue district or location-specified/tailored warnings and factor in infrastructure, local population, settlements, land use as well as other elements.
Mapping of infrastructure
Disaster management agencies may make extensive use of geological, cartographic, and hydrological data available for a given district. For instance, in case of forecasts of wind up to 160 km/hr, the system will warn about the kind of infrastructure at risk, which may be mapped in advance.
According to Mohapatra, IMD’s forecast accuracy is now at par with leading centres of the world. Cyclone track forecast errors have reduced from 124 km in 2009-13 to 86 km in 2015-19 for 24-hour forecasts; from 202 to 132 km for 48-hour forecasts; and from 268 to 177 km for 72hour forecast.
Better forecasts, tracking
The 24-hour cyclone landfall forecast error has reduced from 91 km to 42 km during the period under reference. Error in the intensity forecast is about 10-15 knots for 24-72-hour predictions. Still, there are gaps in technology vis-a-vis capability, Mohapatra said.
These relate to detailed cyclone structure and dynamics; the interaction between a cyclone, ocean and surrounding environment; and internal physical and dynamical processes in clouds. He also referred to gaps in observational and modelling systems for forecasts with a high spatial resolution which too call for better forecast skills.