Climate change will have many devastating effects related to changes in weather patterns, but the most damage will be caused by rising sea levels and nowhere more than on inhabited islands that will soon be underwater.
Global sea levels have risen by about 20 centimeters since 1870, and according to models from the Intergovernmental Panel on Climate Change they could rise by another meter or more by the end of the century.
“No one better understands the grave risks posed by climate change than [Small Island Developing States],” said Baron Waqa, president of the Republic of Nauvu and chair of the Alliance of Small Island States (AOSIS), at the 2014 United Nations Climate Summit in New York City. “Climate change and sea level rise are already threatening our viability and even our existence as sovereign nations.”
The world's 52 island nations -- home to an estimated 62 million people -- are slowly being swept away by sea-level rise.
Depending on regional influences, like nearby melting glaciers, ocean currents, and even tectonic activity, sea level rise can happen at different rates in different areas. The UN reports that sea level rise on these islands is up to four times the global average, and it's already driving inhabitants away from their homes.
This map shows the average annual sea level rise for various Pacific islands between 1992 and 2010. You can see how variable these measurements are: the increase is 2.6 millimeters off the coast of Kiribati, but is nearly 17 mm in Micronesia.
The nation of Kiribati is about halfway between Hawaii and Australia and is made up of 32 low-lying atolls and one raised island. Its land sits about 2 meters above sea level on average, and it's quickly disappearing. By the end of century, or perhaps sooner, Kiribati could be gone.
There's been an average sea level increase in Kiribati of 2.6 mm per year between 1992 and 2010. Even without factoring in future accelerated sea level rise due to rapid glacial melting and thermal expansion, such a trend would suggest a sea-level rise of nearly 30 cm by the end of the century.
The president of Kiribati, Anote Tong, has bought 6,000 acres of land on the Fijian island of Vanua Levu -- a deal that cost the country more than $8 million -- in order to relocate the more than 104,000 people that live on Kiribati.
Some people have already been displaced. In fact, villagers on Abaiang, one of the Kiribati Islands, had to relocate the entire village of Tebunginako to escape the rising seas.
The Maldives face a similar threat. Consisting of more than 1,100 islands to the west of India, the Maldives is the world's lowest-lying nation. On average the islands are only 1.3 meters above sea level.
A Maldives government report from 2007 reported a long-term annual sea level increase of 1.7 millimeters per year and predicted sea level to rise by anywhere from 9 to 88 centimeters by the end of the century. And on top of the rising seas, many of the islands are already reporting significant beach erosion, which only shrinks them further.
Seychelles is another nation in the western Indian Ocean facing the destruction of sea level rise. It consists of 115 granite and coral islands with a population of nearly 100,000.
Some countries, like the Federated States of Micronesia, are taking the lead on climate policy to try and fight the effects of climate change. Micronesia is made up of 607 mountainous islands and low-lying coral atolls that are being eroded away by rising sea levels. The islands are east of the Philippines and have a population of around 105,000.
There's definitely cause for alarm. The International Climate Change Adaptation Initiative predicts sea level to rise by 16 to 62 inches -- that's about 40 to 158 cm -- by the end of the century.
Palau, a group of more than 300 islands about 500 miles southeast of the Philippines, is geographically part of the island group that makes up Micronesia. Its population of more than 21,000 is also at risk.
The Palau Conservation Society writes, 'Rising sea temperatures cause widespread coral bleaching, threatening Palau's tourism industry and fisheries livelihoods. Sea level rise threatens outer island atolls and coastal habitats, as well as the communities and animal populations that rely on them.'
As the plight of Kiribati has shown, relocation is the only hope for many people at this point, including those living on the Carteret Islands. The Carterets are located in the south-west Pacific Ocean near Papua New Guinea. They're home to about 2,000 people -- although probably not for long, as some scientists believe the islands will be submerged this year.
Already, saltwater intrusion in the soil on the Carterets has made it extremely difficult to grow food on the islands. There's an ongoing effort to relocate the families living on the Carteret Islands to the nearby larger island of Bougainville.
Residents of the Solomon Islands are also preparing for evacuation. The Solomon Islands lie east of Papua New Guinea, and have a population of about 610,000.
Residents of the town of Choiseul have plans to build a new town on the nearby mainland. Other areas in the Solomon Islands have been exploring adaptation techniques, such as installing rainwater tanks to collect salt-free drinking water.
Tuvalu consists of six true atolls and three reef islands that has a population of nearly 11,000. The highest point in the country is less than five meters above sea level, and most of it is less than a meter above.
In addition to the threat of flooding by sea level rise, Tuvalu's soil -- like that of the Carterets -- is suffering thanks to saltwater intrusion. The increasingly salty soil makes it difficult to grow crops for food.
The Torres Strait Islands are familiar with climate change refugee status. They're located between Australia and New Guinea and are made up of more than a hundred islands with a population of around 7,000.
The United Nations declared the approximately 100 residents of Tegua, part of the Torres Strait Islands, the first climate change refugees in 2005. These residents had to be relocated further inland on the island after the rising sea repeatedly swamped their homes.
The small island states expressed their concerns again this past December at the UN climate change conference in Lima, Peru, pictured here. By the end of this year, all attending nations at the conference are expected to submit plans for cutting carbon emissions and halting the worst effects of climate change, including accelerated sea-level rise.
For some islands, such as the Carterets, it may already be too late. But for others, the mission to slow global climate change is one that could mean the difference between existence and obliteration.
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