The Maldives have been in the news a bit lately, sometimes for good reasons (like democratically electing the current president and moving out of a dictatorship of nearly 30 years; or for their amazing coral reefs) and sometimes for bad reasons (like a Maldivian who professed he was an atheist and was then arrested but let go after he recanted; or the western couple who had a marriage ceremony at Vilu Reef Resort and the Maldivians recited slander and curses at the couple in their local language, which was discovered after the happy couple posted their video on YouTube and it was translated by a concerned Maldivian).
Having lived in the Maldives for two years, I've been asked on multiple occasions how long the Maldives have before sinking into the ocean. In reality, the fate of the Maldives, like those of the coral reefs that created them, is likely to follow a course whereby they are still around a hundred years from now but where they probably will look a lot different than they do today.
I thought that I would clear up a misconception: the Maldives are not sinking. Rather, it is feared that as the lowest-lying nation in the world, they will be the first to succumb to rising sea levels, which is predicted to rise by about 1 meter (3.34 feet) over the next 100 years. As a country with an average height above sea level of just over 4 feet and a highest elevation almost certainly below 20 feet (no country wide survey has taken place and satellite imagery cannot penetrate dense tree cover), the Maldives certainly has a lot to lose from rising sea levels (illustrated in the figure above from Der Spiegel, the German newspaper).
However, in my experience in the Maldives and my understanding of global climate change, I believe the Maldives will still be around in 100 years at current rates of sea level rise, but that perhaps as much as 30+ % will be submerged. Of course, if all the ice on Greenland melted, the global sea level will rise 10 meters, which will spell the doom for the Maldives and a number of other low-lying nations or regions (e.g., Bangladesh, Texas and the Gulf coast of the United States, and many Pacific Island nations).
Having lived there, I think there are 3 main threats to the survival of the Maldives: 1) die-off of corals, mostly through mass coral bleaching events, especially following the 1998 El Niño-Southern Oscillation event that killed over 70% of corals throughout the Maldives; 2) increasing beach erosion from changing weather patterns, exasperated by still-recovering reefs that no longer block sand from leaving the islands; and 3) sea level rise.
One potentially bright spot for the Maldives was noted by Dr. Paul Kench of the University of Auckland in New Zealand, whom has been conducting detailed seasonal geomorphology mapping of Maldivian islands. He discovered at least one island with evidence that 2,500 years ago, the sea level surrounding the Maldives was 50 cm higher than today's sea level. His work has shown that the Maldives can still exist with higher sea levels but also point out that their survival depends on the dynamic ability of coral sand islands to move with changing weather patterns. He found that round islands can shift around on the edge of a reef much easier than elliptical-shaped islands, which tend to be more static. Therefore, the round islands of the Maldives will likely just move around and adjust to changing weather patterns and sea levels, while the longer islands may erode away. This dynamic ability of the Maldives was noted by past explorers (and mentioned in one of Charles Darwin's works on coral reefs and atoll formation) as well as sea-farers from Zanzibar, who traded between Oman and India, calling the Maldives the land of shifting islands.
Unfortunately, there are two main obstacles standing in the way of the natural ability of the Maldives to respond to climate change.
First, the Maldives, at least for the last 1,000 years and confirmed by the oral traditions of Maldivians, have had a stable climate dominated by two shifting monsoons. The winds and rains blow in from one direction for half of the year and the other direction the other half of the year (with a buffer between the seasons). These monsoons are because of the Himalaya Mountains, whereby during winter they pump cold air down their slopes and into India and further down into the Maldives, whereas the other half of the year winds blowing off Africa and the Arabian Peninsula dominate the climate. The problem is that at least for the last 20 years, the traditional Maldivian calendar has become less accurate at predicting the shifting seasons as a result of changing weather patterns. Now, the monsoons aren't behaving exactly like they are "supposed" to (or historically have). Traditionally dry seasons are now wet and vice versa. Not only does this affect tourism but it also affects weather patterns and I have personally witnessed an out-of-season storm come through and carry away 1 meter of beachfront in a single afternoon on a small (but typical) Maldivian coral island. Because a lot of coral is still dead from the 1998 El Niño and subsequent bleaching events, most of the sand I witnessed being carried away crossed over the reef into deeper waters. Therefore, that sand was "lost" as far as island formation was concerned. This is why I personally believe that beach erosion is the greatest threat facing the Maldives today.
Secondly, people now inhabit the Maldives, along with lots of resorts. About 300 islands are now occupied out of a total 1,190 or so. With population growth good and resorts with million-dollar villas counting on specific beach configurations, people don't want to have to deal with the natural ability of islands to survive changing wave patterns through shifting around. When a beachfront villa is destroyed because all the sand surrounding it is undercut, a number of resorts (and local islands as well) have adopted sea walls around the islands. However, most of the sea walls are built on top of the very reefs that tourists come to see (and even if tourists didn't come to see them, healthy reefs are vital to the survival of the Maldives as far as island formation goes). And while the sea walls do protect the beach and its sand, they prevent water flow (their main function), thereby killing most of the coral inside their barriers. As a result, the lagoons get static water and lower oxygen levels, leading to cyanobacteria (blue-green algae) and other nasty shifts in the ecosystem. However, sea walls may be one of the easiest ways to save the Maldives, though the reefs tend to die as a result of trying to save the islands in their current shape configuration to suit human needs. Unfortunately, this practice does not seem like it will change too quickly as the alternative would be to perform multi-year surveys of beachlines _before_ building any structures. And with leases typically only 25 years long and costing millions of dollars, companies want to build right away and recoup their investment costs.
There are a few resorts with good environmental track records, but I don't want to be partisan so I just encourage interested parties to do their research. Trust me, the list is short compared to the 100-150 resorts already in (or being planned for) the Maldives. But just like I also believe that corals will survive into the 22nd century, I'm not so sure that large reefs will survive at the current rate of climate change and exploitation. Already 25% of reefs worldwide are destroyed beyond repair in our lifetimes and another 25% are severely impaired. Following the 1998 El Niño alone, nearly 13% of corals died worldwide (that's 1 out of 8 corals on the planet) as a result of temperature-induced bleaching. Most of the Caribbean is already effectively dead from a healthy ecosystem perspective and something like only 3% of Caribbean reefs are still as diverse as they were 30 years ago. Couple coral loss with overfishing and mass killing of sharks (40-200 million sharks are killed each year) and large herbivores (like sea turtles) and the fate of reefs are grim. But nature always finds a way. It just may be that the "way" that nature adjusts is in a manner completely foreign to what we as people consider beautiful.
I believe that every environmental problem in the world can be solved by removing people. Of course, this is impractical. However, I also know that all environmental degradation can be stopped and support even higher population densities than today using technology already developed. The problem is that there's no mass will to do so. As a result, I suppose we'll all just have to witness the change while doing our small parts to stem the inevitable tide of biodiversity loss. It just may be one "movie" that we don't really want to watch.
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