Our directory of things of interest

University Directory

Rising tides: islands lost to the sea

Micronesia (above), the Solomon Islands and other low-lying Pacific areas are all at risk from rising sea levels, but understanding to what varying degrees is going to be vital to their long-term futures Micronesia (above), the Solomon Islands and other low-lying Pacific areas are all at risk from rising sea levels, but understanding to what varying degrees is going to be vital to their long-term futures Photosounds
07 Nov
2017
Numerous low-lying Pacific islands have disappeared under rising seas

At first it was anecdotal evidence. Locals from Pohnpei, an island in the Federated States of Micronesia, told researchers about two islands – Nahlapenlohd and Kepidau en Pehleng – that had disappeared beneath the waves in living memory. Taking to the skies, Patrick Nunn, a climatologist from the University of the Sunshine Coast in Queensland, revealed that another six uninhabited islands have been submerged since 2007.

The findings are part of a worrying trend emerging from Pacific island nations. Last year, satellite imagery of the Solomon Islands showed that five of its reef islands had vanished since the mid-20th century. While none of those were inhabited, a further six had lost large portions of land, forcing the relocation of two villages.

‘At least 11 islands across the northern Solomon Islands have either totally disappeared over recent decades, or are currently experiencing severe erosion,’ says Simon Albert, a senior research fellow at the University of Queensland.

Both aerial surveys suggest that the low-lying islands in Micronesia and the Solomon Islands are providing a glimpse into the future for low-lying Pacific regions, which experience seven to 12 millimetres of sea level rise per year – well above the global average of three millimetres.

However, Albert stresses that the island losses are not solely being caused by climate change – wave energy and climatic cycles are playing a role too. Specifically, trade winds spurred by the Pacific Decadal Oscillation, a long-lived El Nino-like pattern of climate variability, are helping to push up sea levels, while increasing wave energy is making some islands more at-risk than others. ‘Twelve of the islands studied in the Solomons demonstrated little noticeable change in shorelines, despite being subject to the same sea-level rise,’ he explains. Islands exposed to higher wave energy fared much worse.

Similarly, Nunn observed that the inhabited Micronesian island of Pohnpei showed ‘fewer effects than might be expected from recent sea level rise’, most likely because it is protected from waves by a fringe of mangrove forests.

Nunn believes that further understanding of specific conditions such as mangroves, sediment dynamics and wave energy will be an essential part of island resilience in the decades to come

This was published in the November 2017 edition of Geographical magazine.

Related items

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Climate

Protestors from the global south were physically removed yesterday from…

Climate

Climate NGOs point fingers at nations holding back climate crisis…

Climate

The Paris Agreement has reached adolescence. Its final stages of…

Climate

A report presented at COP25 highlights the trouble with tourism,…

Climate

For the 25th time in history, the United Nations has…

Wildlife

The Wildlife Photographer of the Year’s Rising Star winner brings…

Energy

Abandoned coal mines contain a precious resource in the warm…

Climate

Marco Magrini wonders if the annual gathering of world leadership…

Wildlife

A new animation produced by the charity Born Free raises…

Wildlife

The United States is grappling with a wild pig invasion.…

Wildlife

Increased interest in the farming of endangered animals as a…

Geophoto

Will 2019 go down as the year that the world…

Climate

Large-scale air travel is under public scrutiny, and refusing to…

Climate

A review of climate crisis coverage in the global media…

Oceans

Marco Magrini looks at the carbon capturing power of the ocean’s…

Oceans

Marine Protected Areas are designed to benefit the marine ecosystem…

Climate

The link between China’s economic growth and increased pollution has…

Climate

An analysis of nine year’s worth of lightning data, covering…

Climate

When getting on ‘board’ with sustainability is the entire goal

Oceans

Many scientists believe that jellyfish numbers are increasing, pointing to…