FOR most of my working life, a sea-level rise has been spoken of in the future tense, a problem for our grandchildren. That language is dangerously out of date.
The water is already here. It is in the wells of villagers in coastal Kedah whose drinking water has turned salty. It is in the streets of Shah Alam and Taman Sri Muda in Selangor, where the December 2021 floods rose to 4m in places and displaced tens of thousands in days.
In April 2026, I joined 25 other commissioners worldwide in launching the Lancet Commission on Sea-Level Rise, Health and Justice. Our co-chair, Christiana Figueres, architect of the Paris Agreement, has called sea-level rise “the mother of all injustices”.
She is right. By 2100, up to 410 million people will live on land below high-tide levels. In 14 Pacific island countries, 62% of health facilities sit within 500m of the sea or a river. The hospitals built to save lives are themselves on the front line.
As far as I can tell, Malaysia tends to think of this as someone else’s emergency. It is not. The 2021 to 2022 floods cost the country RM6.1bil, equivalent to 0.4% of GDP in a single event, and only around a third of those losses were insured.
The Natural Resources and Environmental Sustainability Ministry has identified 111 towns and cities along Peninsular Malaysia’s coast as at risk.
Sea levels are projected to rise 0.4m to 0.7m by 2100, with greater magnitudes in Sabah and Sarawak. Johor’s southern industrial and port corridor sits on highly vulnerable land. Coastal erosion is already eating into Miri, Sarawak, and much of Sabah’s coastline faces growing inundation risk.
These are not projections about some distant future. They are the present, accelerating.
The health consequences follow directly. Dengue seasons are lengthening as temperatures rise, with Kuala Lumpur and surrounding regions among the most vulnerable.
Leptospirosis, cholera, typhoid, and dysentery all spike when sewerage systems fail after floods. Salinity intrusion in coastal Kedah and Kelantan is likely driving higher rates of pregnancy-related hypertension and renal disease, consistent with what researchers have documented in comparable coastal settings in Bangladesh.
Most of these burdens fall on people who can least afford to bear them, and most of the mental health consequences of displacement, the anxiety, depression, and post-traumatic stress that follow repeated flooding, go entirely unmeasured.
And yet Malaysia is not without resources. We have a maritime space twice the size of our land area. We hold some of the most biodiverse mangroves on earth. Our fisheries communities carry generations of knowledge about living with water rather than fighting against it.
In Vunidogoloa, Fiji, 26 households chose managed relocation on their own terms, and it worked precisely because the community led the process. In Bangladesh, hundreds of thousands have returned to salt-tolerant crops and centuries-old floating garden techniques.
Malaysia can do all this at a far greater scale and has the institutional foundations to do so.
Two of them deserve particular attention. The 13th Malaysia Plan’s Blue Economy Blueprint, currently being formulated, could lift our marine economy from 23% of GDP today to an estimated RM1.4 trillion by 2030.
But a blue economy measured only in growth figures is just an ocean economy with a fashionable name. A genuinely transformative one treats mangroves, seagrass, and coral reefs as critical public health infrastructure; a healthy mangrove buffer defends a coastal hospital from storm surge as effectively as a concrete sea wall at a fraction of the cost.
The second foundation is the National Planetary Health Action Plan, launched in November 2025 and built over three years with input from more than 3,500 contributors. It is the first framework in this region to explicitly connect ecological integrity with public health and economic resilience, and the Planetary Health Alliance has recognised it as among the most ambitious science-based responses globally.
Both foundations exist. What they lack is urgency and real money.
Four things need to happen now. First, the National Planetary Health Action Plan must be backed by real and committed political engagement and funding, including for the governance arrangements proposed within it; a framework built over three years with input from more than 3,500 contributors cannot be left to stall for want of a budget.
Coastal health facilities must then be mapped against sea-level projections and prioritised for retrofit, as Fiji has systematically done. A national managed-relocation policy must be developed before displacement becomes chaotic and its costs crush the poorest communities.
And finally, Malaysia should be leading the region in demanding loss and damage finance from the world’s largest greenhouse gas emitters; not from a position of innocence, as Malaysia’s own carbon trajectory demands scrutiny, but from one of solidarity with the far more vulnerable nations alongside whom it sits in this region.
Following the International Court of Justice’s 2025 advisory opinion establishing binding state obligations on climate action, the legal case has never been stronger. This is precisely the moment to make it.
Anote Tong, former president of the archipelagic nation Kiribati, once said it more starkly than I ever could: “We might be on the frontline today, but others will be on the front line next.”
Malaysia is next. The sea will not wait. Neither should we.
Prof Tan Sri Dr Jemilah Mahmood, a physician and experienced crisis leader, is the executive director of the Sunway Centre for Planetary Health at Sunway University. She is the founder of Mercy Malaysia and has served in leadership roles internationally with the United Nations and Red Cross for the last decade. She writes on Planetary Health Matters once a month in Ecowatch. The views expressed here are entirely the writer's own.
