Explained: Why early warning systems for floods and cyclones fall short

As the 2022 monsoon season spreads across India, triggering devastating floods in Assam and other parts of northeast India, and with climate change exacerbating extreme weather events, we take stock of India's early warning systems in preventing loss of lives, property, crops and infrastructure.

The Indian government says it has modern, sophisticated early warning systems for floods and cyclones. But the lack of impact-based forecasts that identify risks, poor dissemination of information to people, lack of scientific data on the effectiveness of warning systems and lack of localised action plans to follow warnings, are some issues that plague India's Early Warning Systems (EWS), we found.

India experienced two of the world's 10 most financially devastating climate events in 2021. Both events, Cyclone Tauktae and Cyclone Yaas, caused financial losses worth more than $1 billion each, apart from the loss of lives.

Between 2010 and 2021, the number of people dying due to cyclonic storms has increased, and floods and heavy rains have killed around 1,000 every year from 2013 onwards.

We wrote to the Ministry of Earth Sciences (MoES) for the reasons behind this increase in mortality, especially with early warning systems. The story will be updated when they respond.

 

Why early flood warning systems do not work

Floods can be riverine, such as the ones seen frequently in Assam or Bihar, or they can be urban floods largely caused by extremely heavy rainfall coupled with poor stormwater drainage systems. In India, heavy rainfall that causes urban floods is monitored by the India Meteorological Department (IMD), while rising water levels in rivers are monitored by the Central Water Commission (CWC).

Presently, there are around 1,600 hydrometeorological sites operated by the CWC across the country, covering 20 river basins. Many of these stations are used as flood monitoring stations for formulating flood forecasts.

Flood forecasting comprises level forecasting and inflow forecasting. Level forecasts help the disaster management agencies in deciding mitigating measures like evacuation, shifting people and their movable property to safer locations. Inflow forecasting is used by various dam authorities to optimise the operation of reservoirs and ensure safe passage of floodwaters downstream. It also helps ensure adequate storage in the reservoirs for meeting the demand of water during the non-monsoon period.

Flood forecasts are issued by CWC at 325 stations (132 Inflow Forecast Stations + 199 Level Forecast Stations), as per a standard operating procedure, and it annually issues over 10,000 flood forecasts. CWC has tied up with Google for dissemination of alerts regarding inundation.

For urban floods, among other things, IMD has a doppler weather radar network of 33 stations to support monitoring and forecast of severe weather, such as thunderstorms and cyclones.

The IMD also operates Flood Meteorological Offices (FMOs) at 14 locations (Agra, Ahmedabad, Asansol, Bhubaneshwar, Bengaluru, Chennai, Guwahati, Hyderabad, Jalpaiguri, Lucknow, New Delhi, Patna, Srinagar and Thiruvananthapuram).

But flash floods also pose a challenge to planning agencies, as they cause widespread destruction in a short span. A 2021 NITI Aayog report recommended a "focus on scientific research in development of a model-based system to forecast flash flood (sic) with sufficient lead time".

 

Recognising their damage potential and a general lack of flash flood warning capabilities, the IMD, in collaboration with the US National Weather Service, has developed a Flash Flood Guidance System (FFGS) for the South Asian region from October 2020. FFGS can provide warnings about 6-24 hours in advance for South Asian countries, including India, Nepal, Bhutan, Bangladesh and Sri Lanka, covering most of the Himalayan region.

FFGS enables all the member countries to issue impact-based flash flood forecasts at the watershed and also at the city level.

"If India has systems like FFGS, was it able to forecast floods like the ones we are seeing in the northeast?," asks Sridhar Balasubramanian, professor of mechanical engineering, and faculty at the Interdisciplinary Programme on Climate Studies Centre at the Indian Institute of Technology, Bombay. "Presently, our models are unable to predict floods even 24 hours in advance. More integrated effort is needed to build a robust system that can forecast floods at least 48-72 hours before the event."

The IMD gives location-specific forecasts for seven days within India's capital cities and issues nowcast (which are urgent forecasts) for the next three hours covering over 700 districts. The same forecasting abilities have been extended to cyclones as well.

Some cities, including Mumbai, have their own EWS for floods. Mumbai's system is named iFlows, but it has shown little success since its inauguration in June 2020. "In Mumbai, iFlows is directly integrated with the forecast, so it is practically the same as the forecast and not an early warning," said Balasubramanian.

India has a proposed outlay of around Rs 15,000 crore for the Flood Management and Border Area Programme (FMBAP) for 2021-26. As part of FMBAP, states can undertake schemes critical for long-term protection against floods, including building infrastructure such as embankments or dams.

We wrote to MoES and the IMD on the effectiveness of the FFGS and iFlows, and will update the story when we receive a response.

Early warning systems for cyclones often inaccurate

The frequency of cyclones and stations reporting very heavy and extremely heavy rainfall has increased in India. Cyclones can cause widespread destruction in a short span.

 

India's National Cyclone Risk Mitigation Project covers six coastal states and they have an outlay of Rs 2,059 crore. Of this, Rs 126 crore is set aside for early warning dissemination systems alone. It also envisages creation of mitigation infrastructure including multipurpose cyclone shelters, underground cabling, roads, saline embankments and bridges in these states.

IIT Bombay's Balasubramanian believes that India's cyclone EWS are better than those for floods.

"India has good models but there is scope for improvement, because once in a while a cyclone comes, like in the case of Asani, that leaves everyone stumped," he said of the cyclone that emerged in the Bay of Bengal in May 2022.

"The IMD-GSS model had predicted that Asani would go towards Orissa and then West Bengal, but it was the European model which suggested [correctly] that it would go towards Andhra Pradesh. In the case of Cyclone Vardah also, the IMD had forecast its track towards south Andhra Pradesh while the European model clearly said Chennai, and that turned out to be correct. Our systems are good but they can definitely be improved." Cyclone Vardah hit India in 2016.

One lacuna was in timely communication of disaster warnings, as the earth sciences ministry admitted in 2019. "This lacuna was severely felt during the Ockhi cyclone in 2017, when fishermen went out for deep sea fishing before the onset of the cyclone and could not be informed about the developing cyclone," the MoES said in a press release in 2019. "This communication gap resulted in loss of life, serious injuries to those rescued, and severe damages to fishing boats and fishing gear."

The Indian National Centre for Ocean Information Services (INCOIS) has developed a device named GEMINI (GAGAN Enabled Mariner's Instrument for Navigation and Information), a handheld device that receives the information transmitted through satellite system 'GAGAN' and sends it to mobile phones through Bluetooth. An app developed by INCOIS converts the satellite messages in the form of readable maps and text. The decoded information can be viewed in any of the languages spoken in the coastal states of India, and is accessible to fishers and others dependent on the sea for their livelihood.

"India has made substantial progress in installing early warning systems, but end-to-end connectivity needs to be improved where information reaches the last mile," said Abinash Mohanty, programme lead at the Delhi-based think-tank Council on Energy, Environment and Water (CEEW), who is currently researching India's EWS.

"If a super cyclone is going to hit, what does it mean for various stakeholders like farmers, fishers, construction workers? Early warnings need to be impact-based. We have strengthened information sources, but that needs to be translated up to the level of communities."

INCOIS also set up a Storm Surge Early Warning System (SSEWS) for the Indian coasts, in collaboration with the IMD, to forecast cyclone-induced storm surges and inundation extent. Under its second phase, National Disaster Management Authority (NDMA), with the IMD, has developed a web-based tool for forecasting the expected damage associated with the landfalling cyclones over coastal districts.

"EWS are being improved but the gap is at the capacity level," explained Mohanty. "Only 30% districts have updated their disaster management plans. Early warnings need to be immediately integrated into planning and disaster preparedness/response protocols. Information is going downwards but sector-specific information, impact-based information needs to be integrated in our daily lives and administrative processes."

"The glaring lack of data around our early warning systems makes for a big gap in our knowledge," says Udit Bhatia, assistant professor of civil engineering at IIT Gandhinagar. "We need to improve our collection and dissemination of data…We may have the tech in place, but if we don't have data to develop scientific models at regional scales, it would become very difficult to plan for extreme events." For instance, he says that because we have never really looked at the data, we do not have a detailed inundation model to try to understand what would be the expected magnitude of flooding.

He asks that India collect more credible data and keep them openly accessible for the scientific community and for policymakers. Then, "we should be able to measure the impact of our interventions as well, otherwise it would be very hard to convince people to believe in EWS".

We wrote to MoES and the IMD to comment on cyclone forecasting accuracy, poor communication and lack of scientific data related to our early warning systems. This story will be updated when they respond.

People are still dying

Despite all the technological advances, expenditure on EWS and the government's claims that deaths due to cyclonic storms have decreased, they in fact increased between 2010 and 2021, according to data from Rajya Sabha.

Both Mohanty and Balasubramanian estimate that the increase in deaths due to cyclones could be due to increase in frequency, intensity of cyclones, increased population and more people living in cyclone-prone regions, among other causes, and may not be a failure of EWS alone.

"At the end of the day, EWS is only one component of our disaster preparedness," said Bhatia. "Even if we have a four-hour flood warning for a certain pocket of the city, if the city's drainage system is not in place, what use is that warning?"

"Contrarily, if functioning response mechanisms are in place but there is little or no early warning, we would still be able to mitigate a lot of damage. Infrastructure cannot change within hours. We have to carefully invest in it, make it climate proof, with people at the centre."