First wave: the presidents of two island nations draft escape plans, anticipating sea level rise.
The Maldives, a chain of some 1,200 islands in the middle of the Indian Ocean, sits about 700 kilometers southwest of Sri Lanka and lures more than half a million adventurers each year. They come to this smallest of Asian countries to scuba dive, surf, fish and cruise in picturesque atolls known for white sandy beaches, crystal-clear turquoise waters and coral reefs teeming with tropical fish of rainbow colors.
About 11,000 kilometers east, halfway between Hawaii and Fiji, lies the little-known nation of Kiribati. Spread over about 3.5 million square kilometers in the central Pacific Ocean, its three major island groups--the Gilbert, Phoenix and Line islands--are too remote and inaccessible to attract much tourism. Kiribati, however, gained scientific notice when it recently set aside more than one-tenth of its territory to establish the world's largest marine preserve harboring one of the last pristine coral reef ecosystems.
These two exotic equatorial paradises may soon be known for something far less desirable than ecological preservation and idyllic vacationing. They are among the lowest spots on Earth and consequently are in danger of becoming the first drowning victims of global warming.
Special and vulnerable
The Maldives and Kiribati highlight a hidden challenge for coping with climate change. It's not just about slowing the emissions of greenhouse gases. It's also about figuring out what to do for localities threatened with the possibility of extinction from rising ocean waters.
"They are like the canary in the coal mine in terms of the dramatic impact of climate change on a whole civilization of people," says Harvard University biological oceanographer James J. McCarthy, past president of the American Association for the Advancement of Science. "They didn't cause the problem, but they will be among the first to feel it."
You might call this a cautionary tale of two countries with vastly more ocean than land, intertwined by similar geologic ancestry and uncertain environmental futures. Although not geographic neighbors, the republics of Kiribati and the Maldives have a lot in common. Born of ancient undersea volcanoes topped with fragile atolls, or islands of coral encircling lagoons, Kiribati (pronounced KEE-reebuhss) and the Maldives (MALL-deevz) face the prospect of slow submersion in this century if temperatures keep increasing and polar ice keeps melting, causing oceanwaters to rise significantly. Most of the countries' small, flat islands are less than two meters above sea level, with many spots even lower.
"They are harbingers of things to come," warns Lonnie Thompson of Ohio State University, who has been studying how global warming impacts polar and tropical glaciers from Antarctica to Tibet. "Unfortunately, because of the lag time, many of these islands are going to suffer from rising sea level regardless of what we do right now," he says. The lag time arises from two factors: Greenhouse gases already in the atmosphere will continue to do damage for years to come, and damage from gases will be added during the time it would take to implement any public or private sector plans to curb future emissions.
R.K. Pachauri, who chairs the Nobel Prize-winning Intergovernmental Panel on Climate Change, warned in December at a United Nations climate conference in Poznan, Poland, that inaction would allow continuing and unabated rises in air and ocean temperatures that could lead to an "abrupt and irreversible change" in the Greenland and West Antarctic ice sheets--and, as a result, a possible sea level rise of several meters. "Small islands, whether located in the tropics or higher latitudes, have characteristics which make them especially vulnerable to the effects of climate change, sea level rise and extreme events," he said.
Amid the rising international din of what to do about climate change, the primary focus has been on reducing future damage to the planet from greenhouse gases emitted from power plants and cars and from those allowed to build up when tropical forests are cleared. Increasingly, however, experts believe that greenhouse gases such as carbon dioxide in the atmosphere may already be making a worldwide environmental impact, contributing to more severe storms, drought, fire and ocean warming. So helping the hardest-hit developing countries adapt to climate change is garnering new emphasis.
But in island and coastal countries, the impact may become so drastic that adaptation is not really an option, eventually forcing people out of their homes. Some vocal leaders in Kiribati, the Maldives and other threatened countries are pressing for international assistance to plan for that worst-case scenario.
In November, Mohamed Nasheed took office as president of the Maldives. The first democratically elected president in this country of about 360,000 people, Nasheed drew international attention with a dramatic proposal to set aside money to purchase land abroad for the extreme case of relocating his country's growing population later this century. In a recent statement to Science News, President Nasheed warned that, without deep cuts in carbon dioxide emissions, projected rises in sea level could ultimately inundate the Maldives.
"If we are unable to save countries like the Maldives, it may be too late to save the rest of the world from the apocalyptic effects of self-reinforcing, runaway global warming," Nasheed said.
He plans to start investing tourism proceeds in a sovereign wealth fund. "This trust fund will act as a national insurance policy to help pay for a new homeland, should future generations have to evacuate a country disappearing under the waves," said Nasheed. "For the sake of the Maldives and the rest of the world, I hope this fund never needs to be used for its ultimate purpose."
London-educated Anote Tong, president of Kiribati since 2003, has traveled the globe throughout his presidency, speaking to the United Nations and at other international gatherings about how climate change threatens his nation's survival. He is not optimistic about getting new land elsewhere, so he has proposed a different solution: starting to send his citizens offshore now, before they are forced to evacuate later. He is already asking for help from nearby countries, including Australia and New Zealand, to train a steady stream of Kiribati's younger people in skilled professions such as nursing, with an initial target of training about 1,000 annually. He wants these citizens to lead the way in finding jobs and permanent new homes abroad.
Sea level forecasting
"There is a need for direct attention to the human dimension," Tong said last fall in Cambridge, Mass., at a public lecture sponsored by the Harvard University Center for the Environment. He called climate change "the most fundamental moral challenge for humans in this century. The future of real people is on the line."
Even a marginal increase in sea level would be disastrous for his country, he said. Warning signs are already appearing, including higher tides and coastal flooding, less rainfall and diminishing freshwater supplies, as well as bleaching of some coral reefs that cradle Kiribati's islands. He said that increased flooding had already forced some villagers to move inland, but that this short trip is a temporary solution since "we're in danger of falling off if we keep moving back." (Many of the country's islands are so narrow that there really is no place to go.) Kiribati has roughly 100,000 citizens and its capital city, Tarawa, suffers from severe overcrowding.
"The reality is that we have to find alternative homes," Tong said. "The levels already in the atmosphere cannot be reversed."
The potential hazards of rising oceans because of climate change are not limited, of course, to small tropical islands. Such islands simply serve as a warning sign for vast coastal parts of the developing and industrialized world, from Bangladesh to Florida, where advancing ocean waters would also threaten areas with extensive shoreline development.
But a realistic, scientific handle on the timing and magnitude of sea level rise over this century remains a moving target. Human-induced climate change can lead to sea level rise by heating of the ocean surfaces, causing the water to expand (thermal expansion). Or it may occur through melting of land-based glaciers and ice caps or the melting and disintegration of polar ice sheets. "The science relating to sea level rise has been in a great state of flux," says Harvard's McCarthy.
The 2007 IPCC report took an extremely conservative approach to potential sea level rise, focusing on thermal expansion. It estimated that sea level increases could range from 0.2 to 0.6 meters by 2100. Experts cautioned, however, that these numbers were highly uncertain and probably underestimated the potential change. The IPCC analysis did not take into account the unexpectedly rapid rate of melting and decay of polar ice sheets, particularly in Greenland, that has been observed recently, or the prospect of accelerated breakdown of polar ice sheets in the future. "That's not something that was anticipated," says McCarthy.
Two other studies published in Science made higher projections of possible sea level rise during the 21st century. In 2007, oceanographer Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research in Germany calculated an estimated range of 0.5 to 1.4 meters. But, Rahmstorf wrote, "the possibility of a faster sea-level rise needs to be considered when planning adaptation measures, such as coastal defenses, or mitigation measures designed to keep future sea-level rise within certain limits." Last September, W.T. Pfeffer of the Institute of Arctic and Alpine Research at the University of Colorado at Boulder estimated that acceleration in ice flow might cause sea level rises of about 0.8 to 2 meters by 2100.
And all bets are off if the Greenland or West Antarctic ice sheet should become seriously unstable. A study in the Feb. 6 Science predicts that meltwater from a collapse of the West Antarctic Ice Sheet wouldn't spread evenly around the globe. It could build up and cause catastrophically higher sea level rise in some areas, such as coastal North America.
Sea rise forecasting will remain uncertain into the foreseeable future. But the levels under discussion are particularly worrisome for low-lying islands, creating growing impatience on the political front. The recent Poland conference was the midway point in a two-year U.N. negotiating process to draw up a comprehensive international climate change agreement to replace the Kyoto Protocol.
The negotiations are scheduled to culminate in a summit meeting in Copenhagen in December 2009, a target that many now consider optimistic, particularly since it will take time for the United States' new administration to get into gear. The Obama team is expected to remove the Bush administration's roadblock and endorse strong controls.
Climate change evacuees
At the Poland meeting, several organizations representing about 40 small island states and the poorest 50 developing countries pushed hard for industrialized nations to take tougher action against climate change. "Together they have been raising their voices here, and I'm hopeful that the call from these countries will be heard," said Saleemul Huq, senior fellow with the nonprofit London research group International Institute for Environment and Development. In a phone interview from the conference, he said that adaptation assistance should include relocation: "The people of small island countries may not be able to live in their own countries anymore, and bigger countries with low-lying coastal areas may need help to move people inland in their own countries."
Assisting possible climate evacuees remains a thorny issue. "This is a very difficult question, as environmental refugees are not [legally] recognized," says Espen Ronneberg, climate change adviser to the Pacific Regional Environment Programme. "Options at the moment appear to be to adapt as much as we can, negotiate strong mitigation efforts and more dollars for adaptation, but at the same time speak to the total disaster that is pending if not enough is done." The goal, he adds, is to prevent, if possible, the most vulnerable populated island states from disappearing entirely.
Many worry that any future actions may come too late to prevent crippling damage to some of the endangered island countries. It is possible that nations such as Kiribati may have already reached a tipping point because of the long delay involved in reducing greenhouse gas levels. There will be a considerable lag time in cutting new emissions significantly, and gases already in the atmosphere may remain there for decades, even centuries, so sea level could keep rising over that period, despite current efforts to slow emissions. Along the way, more frequent or severe ocean storm surges may increase coastal erosion, saltwater may intrude further into soil and freshwater supplies may dwindle due to saltwater, lower rainfall and growing populations. This loss would make it increasingly difficult for people, plants and animals to survive on these islands. "Ocean acidification from climate change can also eat away at the coral reefs, making it harder for them to recover," says Stanford oceanographer Rob Dunbar, who has done research in the Line Islands.
A study from the National Oceanic and Atmospheric Administration reports that "climate change that takes place due to increases in carbon dioxide concentrations is largely irreversible for 1,000 years after emissions stop." The study, published in the Feb. 10 Proceedings of the National Academy of Sciences, was conducted by an international team headed by Susan Solomon, a NOAA senior scientist who works from a lab in Boulder, Colo. It warns that potential increases in carbon dioxide in this century could essentially lock in a sea level rise that could "equal or exceed several meters over the next millennium or longer" and that "many coastal and island features would ultimately become submerged."
Geochemist Daniel Schrag, the head of the Harvard environment center where Tong spoke in September, says, "Climate change mitigation is extremely unlikely to reduce emissions sufficiently to protect places like Kiribati." Schrag fears that Kiribati "literally faces going out of existence," but he is also impressed with Tong's foresight in promoting an orderly long-range plan for his country's highly uncertain future. "I find what the president of Kiribati is doing extraordinary. He's socially engineering an exit solution over a timetable that may take several decades. That's unusual in government," Schrag says, noting that long-term disaster planning is often sorely lacking in other coastal communities. (Schrag is pushing for more climate change planning now in the Boston region.)
Tong is also getting kudos in the scientific and environmental communities for giving back to the world with his important conservation initiative: creation of the Phoenix Islands Protected Area, a remote archipelago of eight coral atolls and two submerged reef systems in an expanse of ocean totaling 410,000 square kilometers, roughly the size of California. The Kiribati government partnered with the New England Aquarium in Boston and with Conservation International to set up an endowment funded by international donors that compensates the country for revenue it will lose from granting fewer fishing licenses. In 2008, the aquarium awarded Tong its top award for "distinguished service on behalf of oceans."
Marine biologist Gregory Stone, the aquarium's vice president for global marine programs, says the isolated Phoenix Islands (where Amelia Earhart's plane may have disappeared) are a treasure because of their pristine wilderness and marine and land biodiversity--including some 120 species of coral and 500 species of reef fish, not to mention countless dolphins, sea turtles and birds (but almost no people). "The islands provide insight into what oceans and coral reefs may have been like 1,000 years ago," offering "a scientific baseline for understanding how climate change and environmental stressors are already impacting other marine communities," Stone says. "The Phoenix Islands give us a window into the past and what a healthy, robust coral reef ecosystem looks like."
Growing greenhouse gas emissions may threaten the future of these irreplaceable environmental treasures, as well as that of other tropical atolls. Their fates hang on whether the international community has the political will to push through tough climate controls and, if so, whether these actions will be sufficient to save vulnerable low-lying islands and coastal areas from encroaching ocean waters.
By 2100 sea level could overtake low-lying coastal areas
Much of the land of the Maldives and Kiribati is about 2 meters above present-day sea level. Below are three predictions for how many meters the ocean could rise this century.
* Visit this story online for links to maps of possible future coastlines.
Cristine Russell is a freelance science writer and senior fellow at the Belfer Center for Science and International Affairs, Harvard Kennedy School.