If sea levels are rising, why is the Maldives still above water?

If you want to see the front lines of climate change, you might think to look at the Maldives. Most of the island country’s land lies less than 1 meter (3 feet) above sea level. Low elevation leaves the Maldives vulnerable as climate change causes sea levels to rise. If that’s the case, why is the Maldives still above water?

Climate contrarians often claim the answer is that climate change isn’t actually affecting the Maldives. This type of claim is false. Sea level rise is a long-term threat, and its dangers will only mount with time. Moreover, sea levels are not the only climate-change-induced threat that menaces the Maldives. We’ve already seen severe effects from some of those other threats, like warming ocean waters.

The story of the Maldives is not as simple as a chain of islands that is doomed to flood. The relationship between islands and sea levels is far more complex. Islands have both natural and artificial ways of adapting to sea level rise, as we detail below.

coral bleaching, saltwater intrusion, and other climate change effects also threaten the Maldives

The Maldives is one of the world’s lowest-lying countries. Located in the Indian Ocean, it is an archipelago of about 1,190 islands, more than 80% of which rise less than 1 meter (3 feet) above sea level. The highest point in the country is widely reported to be a mound on a golf course that tops off at 5 meters (16 feet) above sea level. 

As the planet warms, that sea level rises. There are a few reasons for this. As water heats up, it physically expands; simultaneously, more water enters the ocean from melting glaciers. As a result, the global average sea level has already risen 0.2 meters (0.7 feet) since 1880. The rate is accelerating, and half of that rise has occurred since 1990 – the ocean is now rising approximately 4 cm (1.5 inches) each decade. 

Scientists expect the seas to rise another another 0.5 to 2 meters (1.5 to 6 feet) by 2100; the more greenhouse gas the world emits, the higher the oceans will rise. What’s more, sea level rise plays out over a long time. Even if we completely stop emitting greenhouse gas now, the seas will continue rising for centuries afterward. It’s easy to see why Maldivian people and international scientists alike are quite concerned about the country’s future.

Very far from the islands, online posters cite the fact that the Maldives is still above water to purport that climate change isn’t real or that its effects are being exaggerated. See this recent post on X from Wide Awake Media, which has gathered nearly 200,000 views since 9 March 2025. (Wide Awake Media, which appears to be operated by one person, has a history of spreading similar messaging denying the effects of climate change.) Similar claims have circulated for several years.

Claims like this are false. It is incorrect to claim that, simply because certain climate impacts have not happened yet, there is no reason to worry about climate change in the future. In many cases, scientists expect such impacts to intensify as the Earth’s atmosphere continues to warm and as sea levels continue to rise. This is true for the Maldives, as a 2024 report prepared for the World Bank states:

“The projections […] indicate that up until mid-century the negative impacts are expected to be incremental only. However, by around 2050, negative impacts are expected to escalate quickly, especially under the medium- to high-emission scenarios.”

Sea level rise is a long-term effect of climate change. But we don’t have to wait until 2050 to see climate change impact the Maldives in other ways. We can already see shorter-term effects now.

In 2020, many Maldivian islands saw a die-off of mangroves, plants that grow in brackish (semi-salty) coastal waters^[1]. A 2024 study blamed this die-off on record sea levels, which drenched the mangroves in ocean water too salty for the mangroves’ health. 

The study linked these record sea levels to the Indian Ocean Dipole, in which ocean temperatures swing drastically (much like El Niño and La Niña in the Pacific)^[1]. While the Indian Ocean Dipole is a natural cycle, this 2020 event was the second-warmest on record, and it aligned with warming expected under climate change^[2]. 

Lucy Carruthers, a postdoctoral scholar in coastal studies at East Carolina University and the first author of that 2024 study, told Science Feedback:

“The widespread mangrove dieback that occurred across the nation in 2020 was as a result of extreme increases in sea level rise, offering insights into the potential challenges that lie ahead for coastal ecosystems.”

The Maldives has also experienced episodes of coral bleaching linked to warming waters. In these events, high temperatures strip the corals of their algae. While bleaching doesn’t automatically kill corals, it does deprive them of vital food and makes them more vulnerable to disease. After a severe bleaching event in the late 1990s, Maldivian corals recovered just in time for another major bleaching event to strike around 2016^[3].

We don’t need to look at the Maldives to know what climate change can do. There is unequivocal evidence that Earth’s climate is changing primarily due to greenhouse gas emitted into the Earth’s atmosphere by burning fossil fuels and other human activities^[4]. Elsewhere around the world, we’ve already seen climate change responsible for shrinking sea ice and more severe disasters.

Atoll islands may grow despite sea level rise, not because oceans aren’t rising

It can be easy to assume that the relationship between land and rising seas is straightforward – as seas rise, they flood land. The reality is far more complex.

In fact, there is evidence that many isles in the Maldives have grown in land area. Again, given that sea levels have risen 0.2 meters (0.7 feet) in 140 years, and given that many islands in the Maldives are less than a meter above sea level, how can this be possible? Again, the explanation is not that climate change isn’t affecting the Maldives. Instead, the islands that make up the Maldives have the ability to change with the climate. 

The isles of the Maldives are atolls. An atoll forms when ring-shaped coral reefs build up around volcanic islands. When the volcano goes dormant, it starts to erode. After millions of years, wind and water make the island disappear beneath sea level, but the coral reef remains as a rim. Sand, gravel, and other sediments start to pile atop the coral. If enough sediment builds up, it can pile up above sea level, creating a new ring-shaped island or chain of islands (Figure 1).

In the past decade, scientists have realised that atoll islands aren’t static, but actually dynamic. In other words they can change shape in response to changes around them^[5]. This can happen because, as waves strike atoll islands, they pick up sediment – including the decomposed remnants of coral – and drag it ashore. The sediment tends to pile atop an island, increasing its height and pushing it toward the middle of the lagoon (Figure 2).

More research is needed to better understand this process, but scientists agree that islands can grow in land area as a result. A 2023 study of 49 Maldivian atoll islands between 1969 and 2019 found that more than half had gained area over that time period^[6]. There’s also evidence that atolls in the Pacific have grown^[5].

Still, land area is not the end of the story, and it’s misleading to say that atoll islands are safe from climate change. For one, not all atoll islands will respond in the same way. There is evidence that smaller islands are more prone to losing land in rising seas, while larger islands are more likely to grow in land^[7].

Additionally, as we’ve mentioned, climate change can cause other effects, like mangrove die-offs and coral bleaching episodes. The consequences of this aren’t limited to the mangroves or coral themselves. These coastal ecosystems are crucial ‘sponges’ that absorb a great deal of energy from ocean waves. Without them, an atoll island might flood more easily or erode too quickly^[8]. 

And coral is a crucial source of sediment that atoll islands use in the process of adapting. Carruthers told Science Feedback:

“Stressors like coral bleaching, pollution, and ocean acidification disrupt these crucial marine ecosystems, reducing sediment production. This decrease threatens the islands’ ability to sustain themselves and remain stable in the face of future sea level rise.”

For another example, scientists expect that cyclones will make landfall in the Maldives more frequently. In addition to threatening Maldivian lives and livelihoods, these storms increase the risks of destructive floods and saltwater intrusion, where salty seawater seeps into an island’s fresh groundwater. Many Maldivians rely on groundwater for drinking water, and saltwater intrusion is already a major problem on many of the archipelago’s outer islands.

The Maldives are adapting to a changing climate

Importantly, the Maldivian government and people are not sitting idly in the face of climate change. Many Maldivian islands, including the capital Malé, have built sea walls to protect themselves from flooding. When the 2004 Indian Ocean tsunami struck the archipelago, Malé still flooded, but officials credited its sea walls for blunting the worst of the flood and preventing any deaths in the capital.

More ambitiously, the country is building Hulhumalé, a much larger island next to Malé, linked to the capital and its international airport by road (Figure 2). Hulhulmalé, built by extracting sand from the seafloor and pumping it into shallow parts of the atoll, will have an elevation of around 2 meters (6 feet). 

Climate change is not the only reason to build Hulhumalé – the new island is also intended to relieve a lack of space in densely populated Malé – but Hulhumalé’s architects designed it to remain above water until at least 2100. In theory, Hulhumalé could serve as a refuge for people from lower-lying islands.

Land reclamation has been used to expand the archipelago’s outer islands as well^[9]. Other futuristic ideas include a floating city inside a lagoon, made of homes that will not sink even if water levels rise.

However, these sorts of adaptations come at a cost. In 2021, Aminath Shauna, then the Maldives’ Minister of Environment, Climate Change and Technology, told ABC News that the Maldivian government spends 50% of its budget on combating climate change. If this figure is accurate, then it is valuable funding that isn’t going to other forms of development.

Altering the shapes of islands may also have unwanted consequences for the environment. Building sea walls might ‘harden’ atoll islands’ shorelines, preventing sediment from moving – hardened shores may then make atoll islands more vulnerable to rising seas^[6]. Reclaiming land by pumping sand from the seafloor can damage coral reefs – undermining their ability to provide the sediment for atolls to reshape themselves^[9].

Indeed, a 2019 study found that hardening shorelines and reclaiming land had pushed more than one-fifth of the Maldives’ inhabited islands past an “anthropogenic tipping point” beyond which an island cannot naturally adapt^[9]. People could still live on such an island, but in a future of sea level rise, they might live below sea level and rely on sea walls to stay dry; moreover, saltwater intrusion might leave them without groundwater for growing crops or drinking.

Finally, it’s important to note that our knowledge of how atoll islands work is rapidly changing, as is our knowledge of how human activity affects them. Again, this is not evidence against climate change; it simply means that scientists are gaining a better understanding of a complex subject. 

References

• 1. Carruthers et al. (2024) Sea-level rise and extreme Indian Ocean Dipole explain mangrove dieback in the Maldives. Scientific Reports.
• 2. Wang et al. (2020) A Unique Feature of the 2019 Extreme Positive Indian Ocean Dipole Event. Geophysical Research Letters.
• 3. Montefalcone et al. (2020) Influence of Local Pressures on Maldivian Coral Reef Resilience Following Repeated Bleaching Events, and Recovery Perspectives. Frontiers in Marine Science.
• 4. IPCC. (2021) Climate Change 2021: The Physical Science Basis.
• 5. Masselink et al. (2020) Coral reef islands can accrete vertically in response to sea level rise. Science Advances.
• 6. Carruthers et al. (2023) Coral reef island shoreline change and the dynamic response of the freshwater lens, Huvadhoo Atoll, Maldives. Frontiers in Marine Science.
• 7. Aslam and Kench. (2017) Reef island dynamics and mechanisms of change in Huvadhoo Atoll, Republic of Maldives, Indian Ocean. Anthropocene.
• 8. Amores et al. (2022) Coastal flooding and mean sea-level rise allowances in atoll island. Scientific Reports.
• 9. Duvat and Magnan. (2019) Rapid human-driven undermining of atoll island capacity to adjust to ocean climate-related pressures. Scientific Reports.