Disappearance of five islands in the Pacific blamed on climate change

Scientists in Australia found that rising sea levels and coastal erosion have caused the disappearance of at least five reef islands in the remote Solomon Islands – believed to be the first evidence of climate change wiping out Pacific islands. 

A study of aerial and satellite imagery from 1947 to 2015, backed up by local knowledge and carbon dating of trees,  examined shoreline changes across 33 low-lying  islands.

It found that five have been completely lost and six have been severely eroded, including some that are at least 300 years old. 

The study, published in the journal Environmental Research Letters, found that in the island of Nuatambu, home to 25 families, half of the houses have been “washed into the ocean as a result of dramatic shoreline recession”.

Many of the islands families have fled to a nearby higher volcanic island.

Sirilo Sutaroti, a 94-year-old tribal chief who recently abandoned his village, told the researchers: “The sea has started to come inland, it forced us to move up to the hilltop and rebuild our village there away from the sea.” 

Previous research of islands in the Pacific has found that shoreline changes were caused by a mix of extreme events, seawalls and inappropriate coastal development rather than sea-level rises alone.

But the study found that islands were being directly lost to phenomena caused by accelerating sea-level rises and other recent changes to the climate. 

It found the five lost islands ranged in size from one to five hectares and were previously the site of tropical vegetation that was at least 300 years old.

“Here, we present the first analysis of coastal dynamics from a sea-level rise hotspot in the Solomon Islands,” said the study. 

“We have identified five vegetated reef islands that have vanished over this time period and a further six islands experiencing severe shoreline recession.

Shoreline recession at two sites has destroyed villages that have existed since at least 1935, leading to community relocations.”

Across the Pacific, tiny island nations have been warning about the impact of climate change which could force mass evacuations of entire populations.

About a quarter of Kiribati residents have already moved inland or abroad and eight per cent of those in Tuvalu have moved.

The study, led by researchers at the University of Queensland, focussed on the remote Solomon Islands, which has been a “global sea-level rise hotspot”. 

In the past twenty years, the area around the country has experienced sea level rises of around 7 to 10 millimetres a year – more than double the global average of 3 millimetres a year.

“These higher rates are in line with what we can expect across much of the Pacific in the second half of this century as a result of human-induced sea-level rise,” the researchers said in an article in The Conversation. 

“Many areas will experience long-term rates of sea-level rise similar to that already experienced in Solomon Islands in all but the very lowest-emission scenarios.”