Climate change impact is being felt now and it is getting stronger. It is not the story of future possibilities anymore as predicted by scientists. The Intergovernmental Panel on Climate Change (IPCC) has published reports since 1990 on the science and possible impact of climate change and now reaching its 7th cycle for climate change impact assessment. Clear impacts to be understood by the public include increasing in temperature, increasing in extreme climate events such as higher rainfall intensities, more intense wind and storm as well as super and slower typhoons. Enhancement of climatic patterns such as the El Nino and the Southern Oscillation (ENSO), Maden Julian Oscillation and cold surges will bring higher amount of rain to our country. All of these impacts contribute to higher risk of natural disaster occurrence. Disasters associated to hydro-meteorology will be increased due to climate change, such as floods, drought, landslides, and storm surges.

The November 2024 flood events in the East Coast of Peninsular Malaysia is one of several extreme events we are experiencing due to climate change. The east coast of Peninsular Malaysia was hit by major flood in 2014 and 2007 previously. The rainfall intensities during the 2014 event flood were extremely high due to the cold surges occurring at the northern hemisphere and the occurrence of Madden Julian Oscillation (MJO) as proven by Met Malaysia and satellite data observation by Japan Aerospace Exploration Agency (JAXA). During the December 2014 flood, mild El Nino and the Southern Oscillation (ENSO) influence was reported. However, in November 2024 the associated winds due to the North-east monsoon season carries heavy rainfall across the South China Sea to our peninsular. The meteorological agency, Met Malaysia has predicted the increase possibility of La-Nina in the months between October to December 2024 indicating strong ENSO influence which enhance higher amount of moisture carried by the winds. Warnings information was delivered by Met Malaysia and the Department of Irrigation and Drainage (JPS) through various medias such as TV news, news-papers and social media platforms.

According to rainfall observation recorded by DID stations through its Public Infobanjir website https://publicinfobanjir.water.gov.my/ between 20 and 29 November 2024, several rainfall stations has showed record breaking events as comparison to the 2014 East-coast flood. Rainfall station Sungai Golok at Rantau Panjang, Kelantan has showed higher rainfall intensity with the amount of 1026 mm in November 2024 as compared to 762 mm in December 2014 for a continuous 7-day storm. Another rainfall station JPS Machang has showed a record-breaking event of a total of 1367 mm of rain in November 2024 as compared to 1055 mm in December 2014. In terms of spatial rainfall, record-breaking storm events are concentrated near the coastal area as compared to the 2014 flood where high amount of rain was experienced due to orographic effect near mountainous area (upstream of the catchment) near Gunung Gagau. The November 2024 rainfall shows not just breaking rainfall event for the persistent 7-day storm but also for the storm period of 3 and 5-days. Between the continuous rain period, high tide event also occurred worsening the flood occurrence.

Based on general observation, we might predict that these stronger intensities might indicate the impact of climate change to be stronger in the future. Therefore, it is crucial that our community living at flood risk areas as well as potentially risk areas due to sea level rise and stronger rainfall intensity to be resilience and adapt toward hydrometeorological disaster. Preparing the community to be resilient and adaptable requires strategies and action plans through policies and good disaster governance. One of important non-structural measure which relies on effective communication is a good early warning system installed and operated by the government or local authorities.

An effective end to end early warning system does not rely on only high technological approach but also influenced by effective dissemination and community acceptance to the system. The government of Malaysia has developed various platform for warning information, however there are gaps to fill and improve hence the role of researchers to contribute in improving existing system. A more localised, accurate, and reliable community based early warning system is crucial. More localised and community-based prediction means for example a system which may accurately predict the estimated time of flood arrival. More accurate predictions will increase the community acceptance to a system and enhanced trust and positive reaction from warnings and evacuation orders. New technologies such machine learning approach can be used to improve predictions. A categorical level of warnings to be issued to community is also important in order for the people to understand the scale of the expected flood event.

Structural approach of flood mitigation should consider the element of climate change factor into its design. Flood mitigation structure such as ponds, dams, major drains, pumps, river bunds, and others are usually design using rainfall data that we observed historically. In order to take account future extremes, climate change factor can be used. This factor is calculated using simulated future projected rainfall up to 100 of years data as gathered and reported through the IPCC. Due to the extreme climate and urbanization, multi-function structural approach should be considered to provide water resource and flood mitigation.

Effectiveness of flood mitigation measures in the end highly relies on the community. It is our role to be knowledgeable as well as informed and not to be ignorant to our surrounding and mitigation measures. In order to be disaster resilient, it is the responsibility in taking care of own selves, close- community, the environment and infrastructure near to us.

By Dr. Nor Eliza Alias (Centre for Environmental Sustainability and Water Security – IPASA) and Assoc. Prof. Ir. Dr. Mohamad Hidayat Jamal (Centre for River and Coastal Engineering – CRCE), Research Institute for Sustainable Environment (RISE), Universiti Teknologi Malaysia.

Both are members of the Hydraulics and Hydrology Research Group, Faculty of Civil Engineering, Universiti Teknologi Malaysia.

Source: UTM NewsHub