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Marshall Islanders ‘sitting ducks’ as sea level rises: president

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Geneva (AFP) – Marshall Islands President Hilda Heine stressed Friday the need for dramatic climate action and international support to ensure her people are not left as “sitting ducks” when sea levels inevitably rise.

In an interview with AFP in Geneva, Heine detailed a range of projects underway aimed at helping prepare and adapt her far-flung country, made up of 1,156 low-lying islands, scattered over 29 coral atolls, to rapidly shifting realities brought on by climate change.

“We have to do something, because the only other option is to sit there and wait for the water to come,” she said.

Most of the Marshall Islands lie less than two metres (6.5 feet) above sea level, leaving the Pacific Ocean archipelago’s some 55,000 inhabitants “sitting ducks when it comes to sea level rise,” she said.

The Marshall Islands is among the countries most immediately threatened by unchecked climate change.

Heine lamented that many countries were not taking the threat against small island states seriously enough. She described Washington’s decision to withdraw from the Paris climate accords as “deeply disappointing”.

Faced with lacklustre efforts to slow warning, she said the Marshall Islands’ “survival depends on innovative approaches”, pointing for instance to ongoing discussions about possibly elevating some of the islands.

“In order for the Marshall Islands as a country and as a culture and as a people… to remain in the future, we need to make sure we have higher grounds,” she said.

Heine said the project, which is part of a national climate change adaptation plan due to be published next year, would obviously “cost a lot of money”.

The Marshall Islands has been lobbying the World Bank, the Green Climate Fund and others for a special designation for atoll nations that would give them easier access to grants and loans for climate adaptation projects.

The country itself is spending more to address the negative consequences of climate change already being felt and to prepare for future shifts, including through the building of sea walls around island communities.

The share of its gross domestic product dedicated to disaster risk management and preparedness has doubled from five to 10 percent over the past four years alone, Heine said.

– ‘Disaster’ –

But this may not be enough. The Marshall Islands is also preparing for the possibility that the territory could eventually be swallowed by the sea.

“We want to stay where we are, where we belong, but if it comes to that then we need to consider… strategies,” Heine said.

She pointed out that Marshall Islanders are granted visa-free travel to the United States, and many have already gone there to start fresh.

“If it looks like we won’t be able to save the Marshall Islands, than perhaps more people will take that option,” she said, adding that she would “hate to see that because that means the disappearance of the Marshall Islands as a country”.

“That to me would be a disaster.”

The country is also considering petitioning the UN to ensure that “borders can continue to remain where they are even though they are submerged under water”.

“Even if people relocate elsewhere, their ownership of a certain piece of the ocean would remain,” ensuring rights to fishing and other marine resources, she said.

“I think some kind of discussion along that line needs to start taking place,” she said.

– Nuclear ‘leakage’ –

At the same time, rising sea levels could also exacerbate the threat left by the Marshall Islands’ nuclear legacy.

The US, which detonated 67 bombs at the Enewetak and Bikini atolls between 1947 and 1958 as part of its nuclear test programme, built a dome-shaped structure on Runit island to store the radioactive debris.

Rising seas are now threatening to undermine the structural integrity of the thick concrete dome, which has already developed cracks.

The US energy department insists there is no danger, but the Marshall Islands wants the UN or another country to “help with an independent assessment of the leakage,” Heine said.

“How can it be safe?”


Nature Speaks

Sea levels set to ‘rise far more rapidly than expected’

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New research factors in collapsing Antarctic ice sheet that could double the sea-level rise to two metres by 2100 if emissions are not cut

Antarctica’s snowfall was expected to keep the ice sheet in balance but it is less stable than previously thought.
Antarctica’s snowfall was expected to keep the ice sheet in balance but it is less stable than previously thought. Photograph: Steve Mandel / Barcroft Media

Sea levels could rise far more rapidly than expected in coming decades, according to new research that reveals Antarctica’s vast ice cap is less stable than previously thought.

The UN’s climate science body had predicted up to a metre of sea level rise this century – but it did not anticipate any significant contribution from Antarctica, where increasing snowfall was expected to keep the ice sheet in balance.

According a study, published in the journal Nature, collapsing Antarctic ice sheets are expected to double sea-level rise to two metres by 2100, if carbon emissions are not cut.

Previously, only the passive melting of Antarctic ice by warmer air and seawater was considered but the new work added active processes, such as the disintegration of huge ice cliffs.

“This [doubling] could spell disaster for many low-lying cities,” said Prof Robert DeConto, at the University of Massachusetts Amherst, who led the work. He said that if global warming was not halted, the rate of sea-level rise would change from millimetres per year to centimetres a year. “At that point it becomes about retreat [from cities], not engineering of defences.”

As well as rising seas, climate change is also causing storms to become fiercer, forming a highly destructive combination for low-lying cities like New York, Mumbai and Guangzhou. Many coastal cities are growing fast as populations rise and analysis by World Bank and OECD staff has shown that global flood damage could cost them $1tn a year by 2050 unless action is taken.

The cities most at risk in richer nations include Miami, Boston and Nagoya, while cities in China, Vietnam, Bangladesh and Ivory Coast are among those most in danger in less wealthy countries.

The new research follows other recent studies warning of the possibility of ice sheet collapse in Antarctica and suggesting huge sea-level rises. But the new work suggests that major rises are possible within the lifetimes of today’s children, not over centuries.

“The bad news is that in the business-as-usual, high-emissions scenario, we end up with very, very high estimates of the contribution of Antarctica to sea-level rise” by 2100, DeConto told the Guardian. But he said that if emissions were quickly slashed to zero, the rise in sea level from Antarctic ice could be reduced to almost nothing.

“This is the good news,” he said. “It is not too late and that is wonderful. But we can’t say we are 100% out of the woods.” Even if emissions are slashed, DeConto said, there remains a 10% chance that sea level will rise significantly.

Prof David Vaughan, at the British Antarctic Survey and not part of the research team, said: “The new model includes for the first time a projection of how in future, the Antarctic ice sheet may to lose ice through processes that today we only see occurring in Greenland.

“I have no doubt that on a century to millennia timescale, warming will make these processes significant in Antarctica and drive a very significant Antarctic contribution to sea level rise. The big question for me is, how soon could this all begin. I’m not sure, but these guys are definitely asking the right questions.”

Active physical processes are well-known ways of breaking up ice sheets but had not been included in complex 3D models of the Antarctic ice sheet before. The processes include water from melting on the surface of the ice sheet to flow down into crevasses and widen them further. “Meltwater can have a really deleterious effect,” said DeConto. “It’s an attack on the ice sheet from above as well as below.”

Today, he said, summer temperatures approach or just exceed freezing point around Antarctica: “It would not take much warming to see a pretty dramatic increase [in surface melting] and it would happen very quickly.”

The new models also included the loss of floating ice shelves from the coast of Antarctica, which currently hold back the ice on land. The break-up of ice shelves can also leave huge ice cliffs 1,000m high towering over the ocean, which then collapse under their own weight, pushing up sea level even further.

The scientists calibrated their model against geological records of events 125,000 years ago and 3m years ago, when the temperature was similar to today but sea level was much higher.

Sea-level rise is also driven by the expansion of water as it gets warmer and in January scientists suggested this factor had been significantly underestimated, adding further weight to concerns about future rises.

Recent temperatures have been shattering records and on Monday, it was announced that the Arctic ice cap had been reduced to its smallest winter areasince records began in 1979, although the melting of this already floating sea ice does not push up ocean levels.

Nature Speaks

Sea-level rise ‘could last twice as long as human history’

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Research warns of the long timescale of climate change impacts unless urgent action is taken to cut emissions drastically

Huge sea-level rises caused by climate change will last far longer than the entire history of human civilisation to date, according to new research, unless the brief window of opportunity of the next few decades is used to cut carbon emissions drastically.

Even if global warming is capped at governments’ target of 2C – which is already seen as difficult – 20% of the world’s population will eventually have to migrate away from coasts swamped by rising oceans. Cities including New York, London, Rio de Janeiro, Cairo, Calcutta, Jakarta and Shanghai would all be submerged.

“Much of the carbon we are putting in the air from burning fossil fuels will stay there for thousands of years,” said Prof Peter Clark, at Oregon State University in the US and who led the new work. “People need to understand that the effects of climate change won’t go away, at least not for thousands of generations.”

“The long-term view sends the chilling message of what the real risks and consequences are of the fossil fuel era,” said Prof Thomas Stocker, at the University of Bern, Switzerland and also part of the research team. “It will commit us to massive adaptation efforts so that for many, dislocation and migration becomes the only option.”

The report, published in the journal Nature Climate Change, notes most research looks at the impacts of global warming by 2100 and so misses one of the biggest consequences for civilisation – the long-term melting of polar ice caps and sea-level rise.

This is because the great ice sheets take thousand of years to react fully to higher temperatures. The researchers say this long-term view raises moral questions about the kind of environment being passed down to future generations.

The research shows that even with climate change limited to 2C by tough emissions cuts, sea level would rise by 25 metres over the next 2,000 years or so and remain there for at least 10,000 years – twice as long as human history. If today’s burning of coal, oil and gas is not curbed, the sea would rise by 50m, completely changing the map of the world.

“We can’t keep building seawalls that are 25m high,” said Clark. “Entire populations of cities will eventually have to move.”

By far the greatest contributor to the sea level rise – about 80% – would be the melting of the Antarctic ice sheet. Another new study in Nature Climate Changepublished on Monday reveals that some large Antarctic ice sheets are dangerously close to losing the sea ice shelves that hold back their flow into the ocean.

Huge floating sea ice shelves around Antarctica provide buttresses for the glaciers and ice sheets on the continent. But when they are lost to melting, as happened the with Larsen B shelf in 2002, the speed of flow into the ocean can increase eightfold.

Johannes Fürst, at the University of Erlangen-Nürnberg in Germany and colleagues, calculated that just 5% of the ice shelf in the Bellingshausen Sea and 7% in the Amundsen Sea can be lost before their buttressing effect vanishes. “This is worrying because it is in these regions that we have observed the highest rates of ice-shelf thinning over the past two decades,” he said.

Avoiding the long-term swamping of many of the world’s greatest cities is already difficult, given the amount carbon dioxide already released into the atmosphere. “Sea-level rise is already baked into the system,” said Prof Stocker, one of the world’s leading climate scientists.

However, the rise could be reduced and delayed if carbon is removed from the atmosphere in the future, he said: “If you are very optimistic and think we will be in the position by 2050 or 2070 to have a global scale carbon removal scheme – which sounds very science fiction – you could pump down CO2 levels. But there is no indication that this is technically possible.” A further difficulty is the large amount of heat and CO2 already stored in the oceans.

Prof Stocker said: “The actions of the next 30 years are absolutely crucial for putting us on a path that avoids the [worst] outcomes and ensuring, at least in the next 200 years, the impacts are limited and give us time to adapt.”

The researchers argue that a new industrial revolution is required to deliver a global energy system that emits no carbon at all. They conclude: “The success of the [UN climate summit in] Paris meeting, and of every future meeting, must be evaluated not only by levels of national commitments, but also by looking at how they will lead ultimately to the point when zero-carbon energy systems become the obvious choice for everyone.”

“We are making choices that will affect our grandchildren’s grandchildren and beyond,” said Prof Daniel Schrag, at Harvard University in the US. “We need to think carefully about the long timescales of what we are unleashing.