PETALING JAYA: Although Malaysia is unlikely to see tropical storms forming directly over its territory, the country will continue to experience spillover effects from cyclones developing in neighbouring regions, say experts.
They said tropical storms forming particularly in areas such as the Philippines, Vietnam, the South China Sea and the Bay of Bengal could lead to more intense and extreme rainfall in Malaysia.
National Antarctic Research Centre climatologist Emeritus Prof Datuk Dr Azizan Abu Samah said research showed a clear upward trend in extreme weather events across the region but Malaysia is rarely struck by full-blown tropical cyclones.
“Studies by Malaysian researchers show there is an increase in extreme weather in this region. But for Malaysia, we usually only experience the spillover effects,” he said when contacted yesterday.Out of thousands of cyclones that have hit countries such as the Philippines and Vietnam, Malaysia may only feel the impact of around one in 100, he explained, adding that direct hits remain rare and are not expected to occur frequently.
Prof Azizan said tropical storms in the South China Sea or the Andaman Sea can still intensify rainfall over Malaysia, particularly during the northeast monsoon.
“If a cyclone develops in the Andaman Sea, especially near northern Aceh, it can accelerate the monsoon surge, strengthen winds and produce heavier rainfall in the northern parts of Peninsular Malaysia,” he said.
Asked whether climate change is directly responsible, Prof Azizan said more research is needed, although the link cannot be ruled out.
While the risk of cyclones striking Malaysia remains low, he stressed the importance of strengthening resilience against flooding and landslides.
This, he said, includes public education, robust disaster management systems and curbing deforestation on hillslopes.
“Deforestation on hillslopes must stop. On flat land, water can spread out, but on slopes it rises quickly and becomes dangerous,” he said, citing the Gunung Inas tragedy in Kampung Iboi, Baling, Kedah in 2022.
Emeritus Prof Dr Fredolin Tangang said recent storms such as Tropical Storm Senyar demonstrated that a combination of ocean warming and large-scale climate patterns can create favourable conditions for tropical systems to intensify close to Malaysia.The Academy of Sciences Malaysia fellow said Senyar’s development was not the result of a single factor but rather several processes occurring almost simultaneously.
“One important reason is that sea surface temperatures are generally warmer,” he said, adding that this has been influenced by La Nina conditions, the evolving phase of the Indian Ocean Dipole and long-term global warming.
When La Nina arrives, Fredolin said warm water tends to be pushed towards the region.
“On top of that, seas around South-East Asia, including the Straits of Malacca, have been getting warmer because of global warming,” he said.
These elevated sea surface temperatures, Fredolin explained, provide additional energy for low-pressure systems to strengthen.“A simulation by the World Weather Attribution group has attributed Senyar’s intensification to higher sea surface temperatures over the Bay of Bengal and the Straits of Malacca, suggesting climate change has already played a role in shaping the storm’s strength,” he said.
Fredolin also explained why Malaysia generally does not experience strong typhoons, despite warmer seas.
“Tropical systems are rotating winds, and for them to strengthen, they need the Coriolis force.
“Near the equator, which is below about five degrees north or south, the Coriolis force is weak.
“That’s why we don’t get big typhoons like those affecting the Philippines or Vietnam.”
Fredolin pointed out that Senyar, however, was unusual.
Despite forming near the equator, it then strengthened into a tropical storm, with reported wind speeds of 80 to 90km/h near Aceh.“More strikingly, instead of tracking westwards as most such systems do, Senyar moved southwards along the Straits of Malacca and crossed Peninsular Malaysia.
He added that steering winds at the time, or the influence of strong cold surges that had earlier affected parts of Thailand and northern Malaysia, may have contributed to the storm’s behaviour.
While forecasting tools allow meteorological agencies to issue warnings, Fredolin said prolonged heavy rainfall almost inevitably leads to flooding with the severity of impact depending heavily on conditions on the ground.“When you have unsustainable development, deforestation and poor land-use practices, you increase your exposure.
“That amplifies the impact of flooding, exactly as we have seen in places like Sumatra, where unusual floods carried massive logs and uprooted trees.
In this context, Fredolin said, climate change cannot be viewed in isolation.
“We have to look at the whole framework; not just climate change alone, but how development choices interact with these hazards,” he added.
