Debris from the 2011 tsunami carried hundreds of species across the Pacific Ocean



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Japanese vessel washed ashore on Long Beach, Washington being inspected by John Chapman.
Russ Lewis

Steven Chown, Monash University

When a foreign species arrives in a new environment and spreads to cause some form of economic, health, or ecological harm, it’s called a biological invasion. Often stowing away among the cargo of ships and aircraft, such invaders cause billions of dollars of economic loss annually across the globe and have devastating impacts on the environment.

While the number of introductions which eventually lead to such invasions is rising across the globe, most accidental introduction events involve small numbers of individuals and species showing up in a new area.

But new research published today in Science has found that hundreds of marine species travelled from Japan to North America in the wake of the 2011 Tōhoku earthquake and tsunami (which struck the east coast of Japan with devastating consequences).


Read more: Widespread invasive species control is a risky business


Marine introductions result from biofouling, the process by which organisms start growing on virtually any submerged surface. Within days a slimy bacterial film develops. After months to a few years (depending on the water temperature) fully formed communities may be found, including algae, molluscs such as mussels, bryozoans, crustaceans, and other animals.

Current biosecurity measures, such as antifouling on ships and border surveillance, are designed to deal with a steady stream of potential invaders. But they are ill-equipped to deal with an introduction event of the scale recorded along most of the North American coast. This would be just as true for Australia, with its extensive coastlines, as it is for North America.

Mass marine migration

Marine animals were transported vast distances on tsunami debris.
Carla Schaffer / AAAS

This research, led by James Carlton of Williams College, shows that over a few years after the 2011 earthquake and tsunami, many marine organisms arrived along the west coast of North America on debris derived from human activity. The debris ranged from small pieces of plastic to buoys, to floating docks and damaged marine vessels. All of these items harboured organisms. Across the full range of debris surveyed, scores of individuals from roughly 300 species of marine creatures arrived alive. Most of them were new to North America.

The tsunami swept coastal infrastructure and many human artefacts out to sea. Items that had already been in the water before the tsunami carried their marine communities along with them. The North Pacific Current then transported these living communities across the Pacific to Alaska, British Columbia, Oregon, Washington and California.

Japanese tsunami buoy with Japanese oyster Crassostrea gigas, found floating offshore of Alsea Bay, Oregon in 2012.
James T. Carlton

What makes this process unusual is the way a natural extreme event – the earthquake and associated tsunami – gave rise to an extraordinarily large introduction event because of its impact on coastal infrastructure. The researchers argue that this event is of unprecedented magnitude, constituting what they call “tsunami-driven megarafting”: rafting being the process by which organisms may travel across oceans on debris – natural or otherwise.

It’s not known how many of these new species will establish themselves and spread in their new environment. But, given what we know about the invasion process, it’s certain at least some will. Often, establishment and initial population growth is hidden, especially in marine species. Only once it is either costly or impossible to do something about a new species, is it detected.

Biosecurity surveillance systems are designed to overcome this problem, but surveillance of an entire coast for multiple species is a significant challenge.

Perhaps one of the largest questions the study raises is whether this was a once off event. Might similar future occurrences be expected? Given the rapid rate of coastal infrastructure development, the answer is clear: this adds a new dimension to coastal biosecurity that will have to be considered.

The ConversationInvestment in coastal planning and early warning systems will help, as will reductions in plastic pollution. But such investment may be of little value if action is not taken to adhere to, and then exceed, nationally determined contributions to the Paris Agreement. Without doing so, a climate change-driven sea level rise of more than 1 m by the end of the century may be expected. This will add significantly to the risks posed by the interactions between natural extreme events and the continued development of coastal infrastructure. In other words, this research has uncovered what might be an increasingly common new ecological process in the Anthropocene – the era of human-driven global change.

Steven Chown, Professor of Biological Sciences, Monash University

This article was originally published on The Conversation. Read the original article.

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Australia doesn’t ‘get’ the environmental challenges faced by Pacific Islanders



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Environmental threats in the Pacific Islands can be cultural as well as physical.
Christopher Johnson/Wikimedia Commons, CC BY-SA

Steven Cork, Australian National University and Kate Auty, University of Melbourne

What actions are required to implement nature-based solutions to Oceania’s most pressing sustainability challenges? That’s the question addressed by the recently released Brisbane Declaration on ecosystem services and sustainability in Oceania.

Compiled following a forum earlier this year in Brisbane, featuring researchers, politicians and community leaders, the declaration suggests that Australia can help Pacific Island communities in a much wider range of ways than simply responding to disasters such as tropical cyclones.

Many of the insights offered at the forum were shocking, especially for Australians. Over the past few years, many articles, including several on The Conversation, have highlighted the losses of beaches, villages and whole islands in the region, including in the Solomons, Catarets, Takuu Atoll and Torres Strait, as sea level has risen. But the forum in Brisbane highlighted how little many Australians understand about the implications of these events.

Over the past decade, Australia has experienced a range of extreme weather events, including Tropical Cyclone Debbie, which hit Queensland in the very week that the forum was in progress. People who have been directly affected by these events can understand the deep emotional trauma that accompanies damage to life and property.

At the forum, people from several Pacific nations spoke personally about how the tragedy of sea-level rise is impacting life, culture and nature for Pacific Islanders.

One story, which has become the focus of the play Mama’s Bones, told of the deep emotional suffering that results when islanders are forced to move from the land that holds their ancestors’ remains.

The forum also featured a screening of the film There Once Was an Island, which documents people living on the remote Takuu Atoll as they attempt to deal with the impact of rising seas on their 600-strong island community. Released in 2011, it shows how Pacific Islanders are already struggling with the pressure to relocate, the perils of moving to new homes far away, and the potentially painful fragmentation of families and community that will result.

There Once Was an Island.

Their culture is demonstrably under threat, yet many of the people featured in the film said they receive little government or international help in facing these upheavals. Australia’s foreign aid budgets have since shrunk even further.

As Stella Miria-Robinson, representing the Pacific Islands Council of Queensland, reminded participants at the forum, the losses faced by Pacific Islanders are at least partly due to the emissions-intensive lifestyles enjoyed by people in developed countries.

Australia’s role

What can Australians do to help? Obviously, encouraging informed debate about aid and immigration policies is an important first step. As public policy researchers Susan Nicholls and Leanne Glenny have noted,
in relation to the 2003 Canberra bushfires, Australians understand so-called “hard hat” responses to crises (such as fixing the electricity, phones, water, roads and other infrastructure) much better than “soft hat” responses such as supporting the psychological recovery of those affected.

Similarly, participants in the Brisbane forum noted that Australian aid to Pacific nations is typically tied to hard-hat advice from consultants based in Australia. This means that soft-hat issues – like providing islanders with education and culturally appropriate psychological services – are under-supported.

The Brisbane Declaration calls on governments, aid agencies, academics and international development organisations to do better. Among a series of recommendations aimed at preserving Pacific Island communities and ecosystems, it calls for the agencies to “actively incorporate indigenous and local knowledge” in their plans.

At the heart of the recommendations is the need to establish mechanisms for ongoing conversations among Oceanic nations, to improve not only understanding of each others’ cultures but of people’s relationships with the environment. Key to these conversations is the development of a common language about the social and cultural, as well as economic, meaning of the natural environment to people, and the building of capacity among all nations to engage in productive dialogue (that is, both speaking and listening).

This capacity involves not only training in relevant skills, but also establishing relevant networks, collecting and sharing appropriate information, and acknowledging the importance of indigenous and local knowledge.

Apart from the recognition that Australians have some way to go to put themselves in the shoes of our Pacific neighbours, it is very clear that these neighbours, through the challenges they have already faced, have many valuable insights that can help Australia develop policies, governance arrangements and management approaches in our quest to meet the United Nations Sustainable Development Goals.


The ConversationThis article was co-written by Simone Maynard, Forum Coordinator and Ecosystem Services Thematic Group Lead, IUCN Commission on Ecosystem Management.

Steven Cork, Adjunct Associate Professor, Crawford School of Public Policy, Australian National University and Kate Auty, Vice Chancellor’s Fellow, University of Melbourne

This article was originally published on The Conversation. Read the original article.

Pristine paradise to rubbish dump: the same Pacific island, 23 years apart



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The same beach on Henderson Island, in 1992 and 2015.

Jennifer Lavers, University of Tasmania and Alexander Bond, Royal Society for the Protection of Birds

A few weeks ago, the world woke to the story of Henderson Island, the “South Pacific island of rubbish”. Our research revealed it as a place littered with plastic garbage, washed there by ocean currents.

This was a story we had been waiting to tell for more than a year, keeping our discoveries under wraps while we worked our way through mountains of data and photographs.

Our May 2017 video story detailing the rubbish on Henderson Island.

Everyone wanted to know how the plastic got there, and fortunately that is a question that our understanding of ocean currents can help us answer. But the question we couldn’t answer was: when did it all start to go so wrong?

This is the million-dollar question for so many wild species and spaces – all too often we only notice a problem once it’s too big to deny, or perhaps even solve. So when did Henderson’s sad story start? The answer is: surprisingly recently.

An eloquent photo

During our research we had reached out to those who had previously worked on Henderson Island or in nearby areas, to gain a better understanding of what forces contributed to the enormous piles of rubbish that have floated to Henderson’s sandy beaches.

Then, after our research was published and the world was busy reading about 37 million plastic items washed up on a remote south Pacific island, we received an email from Professor Marshall Weisler from the University of Queensland, who had seen the news and got in touch.

In 1992, he had done archaeological surveys on Henderson Island. The photos he shared from that expedition provided a rare glimpse into the beginning of this chapter of Henderson Island’s story, before it became known as “garbage island”.

Henderson Island in happier times.
Marshall Weisler, Author provided
The same stretch of beach in 2015.
Jennifer Lavers, Author provided

There are only 23 years between these two photos, and the transformation is terrifying – from pristine South Pacific gem to the final resting place for enormous quantities of the world’s waste.

Remember, this is not waste that was dumped directly by human hands. It was washed here on ocean currents, meaning that this is not just about one beach – it shows how much the pollution problem has grown in the entire ocean system in little more than two decades.

To us, Henderson Island was a brutal wake-up call, and there are undoubtedly other garbage islands out there, inundated and overwhelmed by the waste generated in the name of progress. Although the amount of trash on Henderson is staggering – an average of 3,570 new pieces arrive each day on one beach alone – it represents a minute fraction of the rubbish produced around the globe.

Cleanup confounded

In the wake of the story, the other big question we received (and one we should have seen coming) was: can I help you clean up Henderson Island? The answer is no, for a very long list of reasons – some obvious, some not.

To quote a brilliant colleague, what matters is this: if all we ever do is clean up, that is all we will ever do. With thousands of new plastic items washing up on Henderson Island every day, the answer is clear.

The solution doesn’t require travel to a remote island, only the courage to look within. We need to change our behaviour, to turn off the tap and stem the tide of trash in the ocean. Our oceans, our islands, and our planet demand, and deserve it.

However difficult those changes may be, what choice do we have?

Prevention, not cure

While grappling with the scale of the plastics issue can at times be overwhelming, there are simple things you can do to make a difference. The solutions aren’t always perfect, but each success will keep you, your family, and your community motivated to reduce plastic use.

First, ask yourself this: when did it become acceptable for something created from non-renewable petrochemicals, extracted from the depths of the Earth and shipped around the globe, to be referred to as “single use” or “disposable”? Your relationship with plastic begins with the language you use.

But don’t stop there: here are a couple of facts illustrating how you can challenge yourself and make a difference.

Challenge: switch to bamboo toothbrushes, which cost just a few dollars each and are available from a range of online retailers or wholefood shops.

Challenge: switch to products that use crushed apricot kernels, coconut shell, coffee grounds, or sea salts as natural exfoliants.

The ConversationThese are only small changes, and you can undoubtedly think of many more. But we need to start turning the tide if we are to stop more pristine places being deluged with our garbage.

Jennifer Lavers, Research Scientist, Institute for Marine and Antarctic Studies, University of Tasmania and Alexander Bond, Senior Conservation Scientist, Royal Society for the Protection of Birds

This article was originally published on The Conversation. Read the original article.

Sludge, snags, and surreal animals: life aboard a voyage to study the abyss



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The famous “faceless fish”, which garnered worldwide headlines when it was collected by the expedition.
Rob Zugaro, Author provided

Tim O’Hara, Museum Victoria

Over the past five weeks I led a “voyage of discovery”. That sounds rather pretentious in the 21st century, but it’s still true. My team, aboard the CSIRO managed research vessel, the Investigator, has mapped and sampled an area of the planet that has never been surveyed before.

The RV Investigator in port.
Jerome Mallefet/FNRS

Bizarrely, our ship was only 100km off Australia’s east coast, in the middle of a busy shipping lane. But our focus was not on the sea surface, or on the migrating whales or skimming albatross. We were surveying The Abyss – the very bottom of the ocean some 4,000m below the waves.

To put that into perspective, the tallest mountain on the Australian mainland is only 2,228m. Scuba divers are lucky to reach depths of 40m, while nuclear submarines dive to about 500m. We were aiming to put our cameras and sleds much, much deeper. Only since 2014, when the RV Investigator was commissioned, has Australia had the capacity to survey the deepest depths.

The months before the trip were frantic, with so much to organise: permits, freight, equipment, flights, medicals, legal agreements, safety procedures, visas, finance approvals, communication ideas, sampling strategies – all the tendrils of modern life (the thought “why am I doing this?” surfaced more than once). But remarkably, on May 15, we had 27 scientists from 14 institutions and seven countries, 11 technical specialists, and 22 crew converging on Launceston, and we were off.

Rough seas

Life at sea takes some adjustment. You work 12-hour shifts every day, from 2 o’clock to 2 o’clock, so it’s like suffering from jetlag. The ship was very stable, but even so the motion causes seasickness for the first few days. You sway down corridors, you have one-handed showers, and you feel as though you will be tipped out of bed. Many people go off coffee. The ship is “dry”, so there’s no well-earned beer at the end of a hard day. You wait days for bad weather to clear and then suddenly you are shovelling tonnes of mud through sieves in the middle of the night as you process samples dredged from the deep.

Shifting through the mud of the abyss on the back deck.
Jerome Mallefet/FNRS

Surveying the abyss turns out to be far from easy. On our very first deployment off the eastern Tasmanian coast, our net was shredded on a rock at 2,500m, the positional beacon was lost, tens of thousands of dollars’ worth of gear gone. It was no one’s fault; the offending rock was too small to pick up on our multibeam sonar. Only day 1 and a new plan was required. Talented people fixed what they could, and we moved on.

I was truly surprised by the ruggedness of the seafloor. From the existing maps, I was expecting a gentle slope and muddy abyssal plain. Instead, our sonar revealed canyons, ridges, cliffs and massive rock slides – amazing, but a bit of a hindrance to my naive sampling plan.

But soon the marine animals began to emerge from our videos and samples, which made it all worthwhile. Life started to buzz on the ship.

Secrets of the deep

Like many people, scientists spend most of their working lives in front of a computer screen. It is really great to get out and actually experience the real thing, to see animals we have only read about in old books. The tripod fish, the faceless fish, the shortarse feeler fish (yes, really), red spiny crabs, worms and sea stars of all shapes and sizes, as well as animals that emit light to ward off predators.

A spiny red lithodid crab.
Rob Zugaro/Museums Victoria
The tripod fish uses its long spines to sit on the seafloor waiting for the next meal.
Rob Zugaro/Museums Victoria

The level of public interest has been phenomenal. You may already have seen some of the coverage, which ranged from the fascinated to the amused – for some reason our discovery of priapulid worms was a big hit on US late-night television. In many ways all the publicity mirrored our first reactions to animals on the ship. “What is this thing?” “How amazing!”

The important scientific insights will come later. It will take a year or so to process all the data and accurately identify the samples. Describing all the new species will take even longer. All of the material has been carefully preserved and will be stored in museums and CSIRO collections around Australia for centuries.

Scientists identifying microscopic animals onboard.
Asher Flatt

On a voyage of discovery, video footage is not sufficient, because we don’t know the animals. The modern biologist uses high-resolution microscopes and DNA evidence to describe the new species and understand their place in the ecosystem, and that requires actual samples.

So why bother studying the deep sea? First, it is important to understand that humanity is already having an impact down there. The oceans are changing. There wasn’t a day at sea when we didn’t bring up some rubbish from the seafloor – cans, bottles, plastic, rope, fishing line. There is also old debris from steamships, such as unburned coal and bits of clinker, which looks like melted rock, formed in the boilers. Elsewhere in the oceans there are plans to mine precious metals from the deep sea.

Rubbish found on the seafloor.
Rob Zugaro/Museums Victoria

Second, Australia is the custodian of a vast amount of abyss. Our marine exclusive economic zone (EEZ) is larger than the Australian landmass. The Commonwealth recently established a network of marine reserves around Australia. Just like National Parks on land, these have been established to protect biodiversity in the long term. Australia’s Marine Biodiversity Hub, which provided funds for this voyage, as been established by the Commonwealth Government to conduct research in the EEZ.

The newly mapped East Gippsland Commonwealth Marine Reserve, showing the rugged end of the Australian continental margin as it dips to the abyssal plain. The scale shows the depth in metres.
Amy Nau/CSIRO

Our voyage mapped some of the marine reserves for the first time. Unlike parks on land, the reserves are not easy to visit. It was our aim to bring the animals of the Australian Abyss into public view.

The ConversationWe discovered that life in the deep sea is diverse and fascinating. Would I do it again? Sure I would. After a beer.

Tim O’Hara, Senior Curator of Marine Invertebrates, Museum Victoria

This article was originally published on The Conversation. Read the original article.

This South Pacific island of rubbish shows why we need to quit our plastic habit


Jennifer Lavers, University of Tasmania

A remote South Pacific island has the highest density of plastic debris reported anywhere on the planet, our new study has found. The Conversation

Our study, published in the journal Proceedings of the National Academy of Sciences, estimated that more than 17 tonnes of plastic debris has washed up on Henderson Island, with more than 3,570 new pieces of litter arriving every day on one beach alone.

Our study probably actually underestimates the extent of plastic pollution on Henderson Island, as we were only able to sample pieces bigger than two millimetres down to a depth of 10 centimetres. We also could not sample along cliffs.
Jennifer Lavers, Author provided

It is estimated that there are nearly 38 million pieces of plastic on the island, which is near the centre of the South Pacific Gyre ocean current.

Henderson Island, marked here by the red pin, is in the UK’s Pitcairn Islands territory and is more than 5,000 kilometres from the nearest major population centre. That shows plastic pollution ends up everywhere, even in the most remote parts of the world.
Google Maps

A 2014 paper published in the journal PLOS One used data from surface water all over the world. The researchers estimated that there are 5.25 trillion pieces of plastic in the top 10 centimetres of the world’s oceans.

Plastics pose a major threat to seabirds and other animals, and most don’t ever break down – they just break up. Every piece of petrochemical-derived plastic ever made still exists on the planet.

Jennifer Lavers, Research Scientist, Institute for Marine and Antarctic Studies, University of Tasmania

This article was originally published on The Conversation. Read the original article.

Global warming could accelerate towards 1.5℃ if the Pacific gets cranky



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The tropical Pacific has a large say in how fast the world warms.
GTS Productions/Shutterstock.com

Ben Henley, University of Melbourne and Andrew King, University of Melbourne

Global warming is rapidly approaching 1.5℃, but according to our new research, conditions in the Pacific Ocean over the coming decades will determine how fast we get there. The Conversation

In a paper published today in Geophysical Research Letters, we use climate model simulations to quantify how fast global average temperatures will reach 1.5℃ above the pre-industrial average – one of the crucial benchmarks of the Paris Climate Agreement.

The Paris deal calls for governments to pursue the aim of keeping global warming below 1.5℃. But our results suggest that we could hit that level before the end of the next decade if the Pacific Ocean moves into a state we have nicknamed the “cranky uncle” for its effects on global temperatures.

Faster warming

Global temperature records have tumbled in recent years: 2016 was the world’s hottest year on record, the third record-breaking year in a row.

Although human emissions of greenhouse gases are the primary driver of these rising temperatures, there are other factors at play. The climate system is an unwieldy beast, containing a variety of erratic feedbacks and complex mechanisms.

One mechanism with which many people are familiar is El Niño and La Niña, a see-sawing of warm waters across the tropical Pacific every two to seven years. Climate scientists were not at all surprised to see record global temperatures in 2015 and 2016, because of the large El Niño that ended last year.

Another, lesser-known cycle in the Pacific Ocean is the Interdecadal Pacific Oscillation (IPO). Since El Niño and La Niña are Spanish for the “the boy” and “the girl”, we have nicknamed their slower-moving relatives the “cranky uncle”, El Tío, and the “kind auntie”, La Tía.

Like El Niño, warm phases of the IPO provoke a temporary acceleration in global temperature, but over much longer periods, lasting between 10 and 30 years.

The cool La Tía phase of the IPO since around 2000, and its associated slowdown in the rate of global warming, may have lulled us into a false sense of security.

Scientists are now concerned that the next El Tío phase could be on its way, which might sustain the relatively rapid global warming seen over the past few years.

Our research

With this in mind, we decided to investigate how soon we are likely to surpass the 1.5℃ level, both with and without the influence of the IPO.

We used climate model simulations to project global temperatures. The models show temperatures varying significantly from year-to-year and decade-to-decade, as we see in the real world. The centre point of the model projections indicates that the 1.5℃ level would be reached just before 2030, with 75% of the model projections crossing 1.5℃ before 2032.

With the recent slowdown period in mind, we wondered how the next IPO phase, El Tío or La Tía, would influence global temperature. We found that the rate at which global average temperature approaches the 1.5℃ level is influenced significantly by the IPO.

The influence of the IPO on global temperatures towards 1.5°C.
Author supplied

El Tío phases are responsible for an acceleration in global temperature. The centre point of the El Tío projections passes the 1.5℃ level in around 2027, and a quarter of our projections pass 1.5℃ as early as 2024.

For La Tía, the projected rate of warming is reduced, and the centre year is 2031 – the kind auntie gives us a little more breathing space.

So, is the Paris agreement a failure?

No. The Paris agreement is a critically important step in the right direction.

Although we will soon surpass the 1.5℃ warming benchmark, we still have a chance to turn around and head back down the hill. But to reduce global temperatures, we need not only to reduce our net emissions to zero, but to move swiftly into net negative carbon emissions territory. That means that overall we will need to take carbon dioxide out of the atmosphere, not add more.

But we are a very long way from that point. There is a lot of work to do.

The implications of swiftly rising global temperature are many and varied. Our group and other scientists have quantified the changing likelihood of extreme events such as heatwaves, coral bleaching, droughts and floods.

For the next few decades we have to accept that we are likely to see more extreme events as the effect of continued rising global temperatures takes its toll.

We can’t hide from our cranky uncle, but we can limit climate change and its impacts. Although the political will for evidence-based climate policy seems to be waning in some quarters, the message from climate scientists has not changed:

We need swift global cooperation to dramatically reduce atmospheric greenhouse gas concentrations.

Ben Henley, Research Fellow in Climate and Water Resources, University of Melbourne, University of Melbourne and Andrew King, Climate Extremes Research Fellow, University of Melbourne

This article was originally published on The Conversation. Read the original article.

Sea-level rise has claimed five whole islands in the Pacific: first scientific evidence


Simon Albert, The University of Queensland; Alistair Grinham, The University of Queensland; Badin Gibbes, The University of Queensland; Javier Leon, University of the Sunshine Coast, and John Church, CSIRO

Sea-level rise, erosion and coastal flooding are some of the greatest challenges facing humanity from climate change.

Recently at least five reef islands in the remote Solomon Islands have been lost completely to sea-level rise and coastal erosion, and a further six islands have been severely eroded.

These islands lost to the sea range in size from one to five hectares. They supported dense tropical vegetation that was at least 300 years old. Nuatambu Island, home to 25 families, has lost more than half of its habitable area, with 11 houses washed into the sea since 2011.

This is the first scientific evidence, published in Environmental Research Letters, that confirms the numerous anecdotal accounts from across the Pacific of the dramatic impacts of climate change on coastlines and people.

All that remains of one of the completely eroded islands.
Simon Albert, Author provided

A warning for the world

Previous studies examining the risk of coastal inundation in the Pacific region have found that islands can actually keep pace with sea-level rise and sometimes even expand.

However, these studies have been conducted in areas of the Pacific with rates of sea level rise of 3-5 mm per year – broadly in line with the global average of 3 mm per year.

For the past 20 years, the Solomon Islands have been a hotspot for sea-level rise. Here the sea has risen at almost three times the global average, around 7-10 mm per year since 1993. This higher local rate is partly the result of natural climate variability.

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. 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.

Natural variations and geological movements will be superimposed on these higher rates of global average sea level rise, resulting in periods when local rates of rise will be substantially larger than that recently observed in Solomon Islands. We can therefore see the current conditions in Solomon Islands as an insight into the future impacts of accelerated sea-level rise.

We studied the coastlines of 33 reef islands using aerial and satellite imagery from 1947-2015. This information was integrated with local traditional knowledge, radiocarbon dating of trees, sea-level records, and wave models.

Waves add to damage

Wave energy appears to play an important role in the dramatic coastal erosion observed in Solomon Islands. Islands exposed to higher wave energy in addition to sea-level rise experienced greatly accelerated loss compared with more sheltered islands.

Twelve islands we studied in a low wave energy area of Solomon Islands experienced little noticeable change in shorelines despite being exposed to similar sea-level rise. However, of the 21 islands exposed to higher wave energy, five completely disappeared and a further six islands eroded substantially.

The human story

These rapid changes to shorelines observed in Solomon Islands have led to the relocation of several coastal communities that have inhabited these areas for generations. These are not planned relocations led by governments or supported by international climate funds, but are ad hoc relocations using their own limited resources.

Many homes are close to sea level on the Solomons.
Simon Albert, Author provided

The customary land tenure (native title) system in Solomon Islands has provided a safety net for these displaced communities. In fact, in some cases entire communities have left coastal villages that were established in the early 1900s by missionaries, and retraced their ancestral movements to resettle old inland village sites used by their forefathers.

In other cases, relocations have been more ad hoc, with indivdual families resettling small inland hamlets over which they have customary ownership.

In these cases, communities of 100-200 people have fragmented into handfuls of tiny family hamlets. Sirilo Sutaroti, the 94-year-old chief of the Paurata tribe, recently abandoned his village. “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,” he told us.

In addition to these village relocations, Taro, the capital of Choiseul Province, is set to become the first provincial capital in the world to relocate residents and services in response to the impact of sea-level rise.

The global effort

Interactions between sea-level rise, waves, and the large range of responses observed in Solomon Islands – from total island loss to relative stability – shows the importance of integrating local assessments with traditional knowledge when planning for sea-level rise and climate change.

Linking this rich knowledge and inherent resilience in the people with technical assessments and climate funding is critical to guiding adaptation efforts.

Melchior Mataki who chairs the Solomon Islands’ National Disaster Council, said: “This ultimately calls for support from development partners and international financial mechanisms such as the Green Climate Fund. This support should include nationally driven scientific studies to inform adaptation planning to address the impacts of climate change in Solomon Islands.”

Last month, the Solomon Islands government joined 11 other small Pacific Island nations in signing the Paris climate agreement in New York. There is a sense of optimism among these nations that this signifies a turning point in global efforts.

However, it remains to be seen how the hundreds of billions of dollars promised through global funding models such as the Green Climate Fund can support those most at need in remote communities, like those in Solomon Islands.

Simon, Alistair and Javier will be on hand for an Author Q&A 2-3pm Monday May 9 2016. Leave your comments below.

The Conversation

Simon Albert, Senior Research Fellow, School of Civil Engineering, The University of Queensland; Alistair Grinham, Senior research fellow, The University of Queensland; Badin Gibbes, Senior Lecturer, School of Civil Engineering, The University of Queensland; Javier Leon, Lecturer, University of the Sunshine Coast, and John Church, CSIRO Fellow, CSIRO

This article was originally published on The Conversation. Read the original article.