HANYA beberapa hari selepas kecelaruan episod cuaca ekstrem yang berlaku di rantau Asia Tenggara lebih seminggu yang lalu reda, kita dapat memahami begitu dasyat skala impak dialami penduduk di rantau ini berdasarkan pelbagai laporan dalam media dan pelbagai imej serta rakaman video yang mengerunkan, dikongsi melalui pelbagai platform media sosial termasuk YouTube.
Angka kematian sudah melebihi 1,500 termasuk di Sumatera, di selatan Thailand, di Vietnam, di Malaysia dan juga di Sri Lanka dan bilangan ini dijangka meningkat mengambilkira operasi mencari dan menyelamat terutama di Sumatra masih berjalan.
Angka kerugian harta benda juga dijangka tinggi, tidak menghairankan jika ia menjangkau puluhan hingga ratusan bilion ringgit.
Impak bencana ini ke atas penduduk terjejas akan berpanjangan, akan mempengaruhi kehidupan mereka bertahun-tahun lamanya.
Selain Filipina dan Vietnam yang begitu terdedah kepada ancaman taufan saban tahun, datangnya bertubi-tubi dan dijangka kekuatan taufan-taufan ini juga meningkat seiring dengan peningkatan pamanasan global.
Ramai yang beranggapan banyak kawasan lain di rantau Asia Tenggara tidak atau kurang terdedah kepada bencana iklim seperti yang dialami kini.
Siapa dapat menjangka ribut tropika Senyar akan terbentuk di Selat Melaka dan menyebabkan curahan hujan yang sangat tinggi mengakibatkan banjir dan tanah runtuh yang dasyat di Sumatera, dan menyebabkan kehilangan ratusan nyawa dan harta benda?
Secara semula jadi memang agak sukar ribut tropika Senyar ini berlaku mengambilkira ia terbentuk di kawasan latitud rendah di bawah 5oU, di mana daya putaran bumi atau daya Corilois itu kecil bagi sistem seperti ini mengukuh.
Tetapi realitinya ia terjadi dan menyebabkan impak yang begitu teruk malah lebih teruk dari taufan super Fung-Wong yang melanda negara jiran baru-baru ini.
Laluan ribut tropika Senyar ini juga dianggap unik. Ia bergerak ke selatan menerusi Selat Melaka sebelum mendarat dan melewati Semenanjung Malaysia dan seterusnya ke Laut China Selatan sebelum ia diserap oleh taufan Koto yang aktif di timur Vietnam pada ketika itu.
Ia sangat tidak mengikut corak biasa laluan taufan seperti yang terbentuk di bahagian barat lautan Pasifik yang biasanya bergerak ke arah barat dan melencong ke utara disebabkan pengaruh daya Coriolis.
Malah ia membuat pusingan U dan bergerak ke selatan dan ke timur, menunjukkan daya putaran ribut tropika ini mungkin tidak bergantung sepenuhnya kepada daya Corolis tetapi diperoleh dari tiupan angin kencang luruan sejuk yang melanda selatan Thailand dan juga utara Malaysia ketika itu.
Angin luruan sejuk yang saban tahun kita alami dan menyebabkan banjir teruk di Malaysia terutama negeri-negeri di Pantai Timur, bagaikan ‘peluru’ dari utara, berpotensi menjana ribut tropika seperti ini dan membawa kemusnahan lebih teruk berbanding dengan luruan sejuk itu sendiri.
Kita berasa sedikit lega episod pertama luruan sejuk telah berakhir tetapi hanya dalam tempoh lebih kurang seminggu sahaja tiupan angin luruan sejuk mula aktif semula untuk epsiod kedua dan ini dijangka akan menyebabkan satu lagi kecelaruan cuaca ekstrem dalam beberapa hari akan datang yang boleh menyebabkan banjir dan tanah runtuh, termasuk di Sarawak dan Sabah.
Kita berharap, pihak berkuasa MetMalaysia dan Jabatan Pengairan dan Saliran (JPS) dapat mengeluarkan amaran cuaca buruk dan banjir lebih awal untuk penduduk membuat persedian lebih awal bagi menghadapi sebarang kemungkinan.
Begitu keadaannya di Malaysia dan rantau Asia Tenggara, kita terdedah kepada pelbagai pemacu impak iklim atau climate impact driver (CID), satu konsep yang diperkenalkan oleh Panel Perubahan Iklim Pertubuhan Bangsa-Bangsa Bersatu (IPCC).
Apabila CID ini wujud atau berlaku secara serentak, maka kecelaruan akan berlaku dan kebarangkalian impak bencana iklim akan meningkat.
Dalam rencana saya sebelum ini, saya menyenaraikan elemen CID yang berlaku secara serentak dan menyebabkan episod kecelaruan cuaca sebelum ini.
Ini termasuk luruan sejuk, La Nina, IOD berfasa negatif, suhu permukaan laut yang ditinggi di laut sekitar Asia Tenggara dan kelembapan tinggi akibat La Nina dan IOD dan juga pemanasan global.
Semuanya menyumbang kepada kecelaruan cuaca yang kita alami, dan kecelaruan ini akan semakin meningkat jika pemanasan global tidak ditangani dunia secara tutas dan pantas.
Tetapi perkembangan rundingan iklim COP30 di Brazil baru-baru ini amat mengecewakan dan sebagai ahli klimatologi berpendapat kegagalan dunia dalam mencapai kata sepakat mencarta pelan memastikan peningkatan suhu dunia dapat dihadkan di bawah 1.5oC sangat membimbangkan.
Bagaimana lagi kita berharap ia akan menjadi realiti apabila negara besar dan antara pembebas utama gas-gas rumah hijau seperti Amerika Syarikat tidak lagi komited dan sehaluan dengan negara-negara lain dalam nenangani isu perubahan iklim.
Malaysia dan negara-negara membangun di Asia Tenggara akan sentiasa terdedah kepada CID yang boleh muncul secara serentak dan tahap pendedahan ini akan meningkat, seiring dengan pemanasan global.
Tetapi bukan saja CID yang kita khuatir, faktor bukan CID yang boleh meningkatkan risiko impak juga mesti dikawal. Pembangunan tidak mampan, penebangan hutan berleluasa, saliran dan perparitan yang tidak terurus, adalah faktor-faktor bukan CID yang berpotensi mengingkat risiko bencana disebabkan CID.
Kita perlu membangun secara mampan, beradaptasi untuk mengurang impak bencana perubahan iklim yang semakin hari tidak jelas apakah dunia boleh menanganinya.
Kita perlu membina infrastuktur termasuk tambatan banjir yang dapat meningkatkan daya tahan terhadap impak bencana iklim dan memastikan elemen rasuah dan korupsi tidak menghambat usaha kita ke arah ini.
Doa saya episod luruan sejuk kedua ini tidak menjadi kecelaruan cuaca yang teruk seperti minggu lepas. Penduduk perlu bersedia dan memberi perhatian kepada ramalan dan arahan yang dikeluarkan pihak pemerintah.
Prof Emeritus Dr. Fredolin Tangang adalah Profesor Emeritus dalam bidang klimatologi dan perubahan iklim di Universiti Kebangsaan Malaysia, Felo Akademi Sains Malaysia dan kini bertugas di Universiti Brunei Darussalam. Beliau juga bekas Naib Pengerusi Kumpulan Kerja 1 Panel Perubahan Iklim Antara-Kerajaan (IPCC), Pertubuhan Bangsa-Bangsa Bersatu (PBB).
—English version
Malaysia, Southeast Asian region are highly vulnerable, exposed to the impacts of climate-related disasters
ONLY a few days after the extreme weather episode that struck Southeast Asia more than a week ago subsided, we are now able to comprehend the severity and vast scale of the impacts experienced by people across the region based on numerous media reports and the many horrifying images and video recordings shared across various social media platforms, including YouTube.
The death toll has exceeded 1,500, including in Sumatra, southern Thailand, Vietnam, Malaysia, and Sri Lanka, and this number is expected to rise given that search and rescue operations—especially in Sumatra—are still ongoing.
Economic losses are also expected to be very high, and it would not be surprising if they reach tens or even hundreds of billions of ringgit. The impacts of this disaster on the affected communities will be long-lasting, influencing their lives for many years to come.
Besides the Philippines and Vietnam—which are highly exposed to typhoons arriving one after another every year, with their intensities expected to increase in line with global warming—many people assume that other parts of Southeast Asia are not, or are less, exposed to climate-related disasters of the kind now being experienced.
Who would have expected Tropical Storm Senyar to form in the Straits of Malacca and unleash extremely heavy rainfall, leading to devastating floods and landslides in Sumatra and resulting in the loss of hundreds of lives and extensive property damage?
Naturally, the formation of Tropical Storm Senyar is unusual, considering that it developed at low latitudes below 5°N, where the Earth’s rotational force—the Coriolis force—is weak, making it difficult for such systems to intensify.
Yet in reality it occurred and caused severe impacts, even worse than those associated with Super Typhoon Fung-Wong, which struck a neighbouring country recently.
The track of Tropical Storm Senyar was also considered unusual. It moved southwards through the Straits of Malacca before making landfall and crossing Peninsular Malaysia, then heading towards the South China Sea before being absorbed by Typhoon Koto, which was active over eastern Vietnam at the time.
This trajectory deviates significantly from the usual storm tracks in the western North Pacific, where cyclones typically move westwards and curve northwards under the influence of the Coriolis force.
Instead, Senyar made a U-turn and moved southwards and eastwards, indicating that the rotational momentum of this tropical storm may not have depended entirely on the Coriolis force but was instead driven by the strong cold-surge north easterly winds affecting southern Thailand and northern Malaysia during that period.
Cold surges, which we experience every year and which frequently cause severe flooding in Malaysia—particularly in the East Coast states—behave like a “bullet” from the north, with the potential to trigger tropical storms such as this and bring even greater devastation than the cold surge itself.
Although we were briefly relieved when the first cold-surge episode ended, within roughly a week the northeasterly surge became active again for a second episode, which is expected to generate another round of extreme weather in the coming days.
This may trigger floods and landslides, including in Sarawak and Sabah. We hope that MetMalaysia and the Department of Irrigation and Drainage will issue early weather and flood warnings so that communities can prepare in advance.
Such is the situation in Malaysia and across Southeast Asia—we are exposed to multiple climate impact drivers (CIDs), a concept introduced by the Intergovernmental Panel on Climate Change (IPCC), the United Nations’ climate science body.
When several CIDs occur simultaneously, weather instability increases and the likelihood of climate-related disasters rises.
In my previous column, I listed the CID elements that occurred concurrently and triggered the earlier episode of weather disruption.
These included cold surges, La Niña, a negative phase of the Indian Ocean Dipole (IOD), elevated sea surface temperatures in waters surrounding Southeast Asia, high atmospheric moisture associated with La Niña and the negative IOD, and global warming.
All of these contributed to the chaotic weather we experienced. Such disruptions will intensify further if global warming is not addressed decisively and swiftly by the world.
However, the outcome of the COP30 climate negotiations in Brazil recently was deeply disappointing.
As a climatologist, I am concerned that the failure of the global community to reach consensus on a clear plan to limit the global temperature increase to below 1.5°C is alarming.
How can we expect this goal to become a reality when a major global power and one of the world’s largest green house gas emitters, the United States, is no longer committed or aligned with other countries in addressing climate change?
Malaysia and other developing countries in Southeast Asia will remain exposed to CIDs that may occur simultaneously, and this level of exposure will continue to rise in tandem with global warming.
But it is not only the CIDs that we should be concerned about—non-CID factors that can heighten disaster risks must also be managed.
Unsustainable development, rampant deforestation, and poorly managed drainage systems are non-CID factors that can significantly amplify the risks posed by CIDs.
We must pursue sustainable development and enhance adaptation in order to reduce the impacts of climate-related disasters, which are becoming increasingly uncertain as to whether the world can manage them effectively.
We need to build infrastructure, including flood-mitigation systems, that strengthens resilience to climate-related disaster impacts, and we must ensure that corruption does not hinder our efforts.
I pray that this second episode of cold surge does not turn into another severe weather disruption like last week. Residents must stay prepared and pay close attention to forecasts and directives issued by the authorities.
Prof Emeritus Dr Fredolin Tangang is Professor Emeritus in climatology and climate change at Universiti Kebangsaan Malaysia, a Fellow of the Academy of Sciences Malaysia, and is currently serving at Universiti Brunei Darussalam. He is also a former Vice-Chair of Working Group I of the Intergovernmental Panel on Climate Change (IPCC), United Nations.