Mitigating Tropical Cyclone Risks In The Irrawaddy Region

While a geographically vulnerable region, like the Irrawaddy Delta Region, is never hazard-free, regional comprehensive mitigation strategies can still help reduce hazard risks. These include effective prediction and warning systems, hard and soft engineering methods and the community’s awareness and preparedness to tackle potential threats.

Prediction & Warning Systems

Prediction Uses long-term forecasting and short-term storm detection and path prediction to predict the seasonality and frequency of cyclones Uses Doppler radar and satellite imagery to determine the size, speed and distribution of cyclonic winds and precipitation. Uses remote sensing and cyclone modelling to forecast the cyclone path and intensity.

By predicting the cyclone and its estimated arrival, local governments can provide early warning systems to evacuate its people Have proper land-use planning based on risk assessment of the area to advise the public to not live in the most affected areas.

What is in place? Inadequate warning system and lack of radar technology led to an underestimation of the strength of Cyclone Nargis. Improvement in early warning capacity was done through Myanmar’s Department of Meteorology and Hydrology (DMH). They received US$40 million from Japan to develop three weather radar stations in Yangon, Mandalay and Kyaukpyu as well as 30 automatic weather observation stations across the country by 2017. Myanmar’s early warning system is now connected with the DMH at the regional, state, township and district scale through the use of phone or fax. Storm warnings are then given to the village from the township by phone or by deploying an officer to the site, with the village authorities making public announcements via loudspeakers.

As prediction based on modelling of individual precursors is insufficient, Brackenridge et al. (2017) suggested that the modelling should also include the effects on inland rainfall on saturated land too. It is crucial to aggregate these models and present a clear and coherent message to the public to warn or instruct for evacuation. Even with accurate prediction and warning systems in place, there still needs to be a more efficient dissemination of information from the authorities to the public. They can take inspiration from Bangladesh where they sent cyclone warning texts while those in more remote areas were notified via vibrant hot air balloons. These systems only aid in warning the locals and allow them time to react and evacuate the area. There then needs to be other strategies, such as hard and soft engineering, in place to help delay the arrival of TC impacts by giving additional time for people to respond and react.

Hard & Soft Engineering Hard Engineering Coastal Management

Creation of flood defences, such as embankments, levees and seawalls in buffering the coast against incoming floodwaters. The state has decided to invest in embankments seeing flood impacts on its agricultural sector. Since Cyclone Nargis, the state has done some emergency repairs on its embankments and polders to ensure they are functional before planting season

Coastal Shelters

Storm shelters of varying sizes to accommodate 300, 500 and 1, 000 persons, complete with power, water and provisions. Elevated local storm shelters that can withstand TCs and storm surges - where quick evacuation to higher ground is not possible.

Dwellings were modified because most structures in the region were not designed to withstand the devastating cyclonic events. Cyclone shelters were constructed by the government and the UN/INGOs in Yangon (2) and the Irrawaddy Region (54).

Houses with Building Codes

These are well planned, located at the highest spot, elevated on stilts to avoid the waters, built with well-selected materials and constructed with a strong tight frame with deeper foundations, secured with a steep-sided roof. These shelters help prevent and reduce the risk of severe damage in the next disaster.

Those who survived Cyclone Nargis were protected by the shelters which resisted against the strong winds as they were built with stronger materials instead of timber or bamboo, such as houses, monasteries or safer buildings near them. They were also situated on higher grounds.

Soft Engineering Mangroves

Mangrove roots stabilise coastal and river banks to reduce inland flooding. It serves as a protective coastal buffer against storm surges due to their wave attenuation properties and ability to minimise the speed of strong winds. Myanmar has an absence of 70, 000 hectares of mangroves between 1972 and 2005, mainly due to conversion into rice fields and large-scale shrimp and prawn farming.

Hard engineering strategies are naturally anticipatory, and they are built to withstand the highest wave ever recorded. However, it is uncertain that the 'greatest ever' has occurred, leaving the possibility that a wave of greater intensity would strike the same location. Thus, this limits the planners' ability to successfully mitigate all future occurrences of the hazard. Additionally, for soft engineering strategies such as mangrove restoration efforts, not only do they take a longer time, but improper care may undermine these strategies. Conversely, if restored well, mangroves will be an effective long-term measure in buffering the coasts against storm surges, reducing the residents’ vulnerability to them. Despite breaching these expensive structures, they nonetheless help humans earn a few precious extra moments. A region’s vulnerability can only then be effectively lowered with complementary efforts in place to heighten awareness and preparedness.

Community Awareness & Preparedness

Although cyclone warnings are given, people choose to be complacent due to warning disbelief and lack of trust in the institutions, in their prediction accuracy reliability and conduct of evacuation drills. Even though it is difficult to target people’s perceptions, awareness education could come into play to educate the most at-risk groups such as the young and the illiterate so that all members of the community can be effectively alerted prior to an event.

Conclusion

As TCs are beyond our control, those at risk must be proactive. The effectiveness of mitigation strategies hinges on the government’s efficiency in responding and managing the disaster, coupled with the community’s heightened awareness and preparedness to TCs. By implementing this multi-pronged approach, vulnerable communities can adapt and prepare themselves for future TCs.