Escap sees cyclone risk hotspots in Bay, Arabian Sea at baseline warming

The World Meteorological Organisation/UN-Economic and Social Commission for Asia and the Pacific (WMO/Escap) Panel on Tropical Cyclones (PTC) is observing 50 years of existence at a time when the world has more heat in the oceans and atmosphere, which can supercharge cyclones. The PTC was set up in the context of the deadliest tropical cyclone Bhola of 1972 that killed more than three lakh people in Bangladesh.

Intense heat engines 

A cyclone is a heat engine, transferring heat from warm ocean water up into colder layers of the atmosphere, explains Sanjay Srivastava, Chief, Disaster Risk Reduction, Escap. “More heat in the system means more intense heat engines. An ESCAP analysis has identified intensifying and expanding risk hotspots in the Bay of Bengal and Arabian Sea at baseline, 1.5- and 2.0-degree warming, flagging the challenges of resilience in risker times,” Srivastava wrote to businessline.

Hard lesson from Bhola

The hard lesson learnt from Bhola was not having an effective cyclone warning system to forewarn at risk communities. The panel PTC started with six member countries and now comprises of 13 from the Bay and the Arabian Sea regions. Over the last 50 years, the Panel has successfully tracked and monitored cyclones from formation to landfall through cross-border collaboration, involving real-time data sharing and risk information exchange across the common ocean basin, Srivastava said. 

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PTC effectiveness to fore

The positive outcomes in managing two recent cyclones emphasise its effectiveness, he pointed out. On May 14 this year, cyclone Mocha hit Myanmar accompanied by sustained winds of 180-190 km/hr, violent gusts, torrential rainfall and flooding. The landfall region had a most vulnerable context marked by compounding poverty, inequality and environmental degradation. But the impact differed significantly from the 2008 devastation from cyclone Nargis, a storm as powerful as Mocha, which had resulted in the loss of over 1.38 lakh lives in Myanmar.

Cyclones Biparjoy, Mocha

On June 26, cyclone Biparjoy with wind speed of 140 km/h hit the densely populated Gujarat coast in India. Despite its ferocity, no casualties were recorded. The accuracy of early warnings leading to targeted evacuations during Mocha and Biparjoy saved tens of thousands of lives at risk. The Regional Specialised Meteorological Centre (RSMC) within the Indian Meteorological Department was able to forecast these cyclones four days in advance, which gave sufficient lead time for authorities to manoeuver the coastal communities to safer areas. 

IMD’s expert tracking

The PTC notes cyclones in the Bay (Amphan) and Arabian Sea (Tauktae) have shown a rapid intensification, complex tracks and increased curvature. Titli (East Coast of India, 2018) caused landslides and fatal flooding despite precise early warning, resulting in over 50 casualties. Cyclones that intensify rapidly are difficult to forecast and can lead to forecasting errors. For accurate predictions, advanced surveillance should be deployed to detail monitoring of complex cyclone formation, and high-quality modelling frameworks adopted integrating ocean, atmosphere and land phenomena.

Escap methodology

Impact-based forecasting (IBF) narrows the gaps that exist between forecasters and the end-users. Escap has developed a methodology that translates cyclone track, intensity, and landfall prediction into impact scenarios. Anticipatory action (AA) is central to early warning and action, intricately tied to IBF. It plays a key role in proactive measures enhancing to preparedness to mitigate the impacts of cyclones. Operationalising IBF and AA through PTC attachment training and capacity development activities is an important step forward and would see a seven-fold return on investment, Srivastava said.

UN Early Warnings

The UN Early Warnings for All Executive Action Plan 2023-27 is based on four pillars – knowledge of risk, monitoring and forecasting, warning dissemination and communication, and preparedness for response. The effectiveness of multi-hazard early warning systems relies on each pillar and needs to be supported by policy, plans, and financial mechanisms to enable its availability and accessibility. PTC@50 can take forward cyclone early warnings for all its members.

The Secretariat of the PTC is imperative to driving operations and should be strengthened to ensure that the panel is fully owned, funded, administered, and governed by its members. It can be built on the four pillars of cyclone early warnings, following the modality of the Early Warnings for All initiative, through its working groups. The 50th celebration provides an opportunity to rejuvenate PTC ready to manage complex cyclones in riskier times.