Time for that annual warning about the folly of over-developing Australia's coastline due to increased flooding, erosion and sea inundation. A warning that all three tiers of government have blithely ignored for too many years

 

Science and climate modelling has been informing people living in Australia's coastal zones that global warming-induced sea level rises, along with changes in east & west coast current speeds, more erosive wave patterns & increased flooding, will make living along the coastal fringe highly problematic the deeper the earth moves into this era-long climate change.

Coastal residents have been warned every year since at least 2006 and 2022 is no different.

This is the message in 2021-22.

What the NSW Government’s ADAPT NSW has to say about climate change-induced sea-level rise along the state’s coastline:

Projected sea level rise along the NSW coast

There is a direct relationship between climate change and sea level rise. As our climate warms, sea level rises mainly because of thermal expansion (when water warms up, it expands) and melting of snow, glaciers and ice caps (which increases the volume of ocean water). However, sea level rise is also effected by local oceanographic processes (e.g. changes to ocean currents) and changes to land levels.

Sea level rise is projected to accelerate over the 21st century. The most recent sea level rise projections are from the Intergovernmental Panel on Climate Change (IPCC) 6th Assessment Report. The IPCC predict a likely sea level increase on the central NSW coast of

between 0.21m and 1.06m by 2100, and

between 0.28m and 1.95m by 2150.

This is dependent on the level of future greenhouse gas emissions.

IPCC modelling suggests slightly higher sea level rise to the north of the state and slightly lower to the south. These projections do not include processes associated with the melting of ice sheets which for NSW could result in sea level rise of up to 2.3m by 2100 and 5.5m by 2150.

In the longer term, the IPCC show sea level is committed to rise for centuries to millennia due to continuing deep ocean warming and ice sheet melt, and will remain elevated for thousands of years.

If warming is limited to 1.5°C, global mean sea level will rise by about 2 to 3m.

for 2°C, 2 to 6m is expected, and

for 5° 19 to 22m is expected.  

This is the current seawater inundation scenario message in Predicted Coastal Flooding Resulting from Climate Change, based the IPCC Sixth Assessment Report Update 2021.

Examples from Coastal Risk Australia 2100 interactive mapping tool using IPCC scenarios for the period 2021 to 2100.

Sometime in the next 79 years this is what two small coastal towns will probably look like from the air.......

Ballina, New South Wales - blue area seawater inundation at 0.8m

Yamba, New South Wales - blue area seawater inundation at 0.8m

The Daily Telegraph on 18 January 2022:

The Coastal Risk Map shows what Australia will look like if sea levels rise due to climate change, showing how much extra water will filter into our cities and suburbs and the impact it will have on our way of life.

The map was originally created by spatial mapping company NGIS with non-profit partner Frontier SI in 2015, but has recently been updated with new data from the United Nations Intergovernmental Panel on Climate Change’s Sixth Assessment Report.

The sea level projections show that if greenhouse gas emissions are moderated, the ocean may rise by 0.84m by 2100.

But a global rise approaching 2m by 2100 and 5m by 2150 would be possible under a very high greenhouse gas emissions scenario- much higher than first thought.

NGIS Executive Director Nathan Eaton said the aim of the map was to illustrate the data and give Australians a better understanding of how sea level rises could impact their lives.

“Previously the map showed a rise of 0.74m at it’s lowest, that’s since changed to 0.84m,” Mr Eaton said.

“Now less than a metre doesn’t seem like a massive difference to someone, but in low lying areas, even 10 centimetres can make a huge difference.”

Geobiology, archaeology and sea level expert Dr Ben Shaw said the map could be a “wake up call” for authorities on the urgency of curbing climate change.

“It’s phenomenal to see how impacted parts of Australia will be … a real concern for people living in Sydney, across NSW and around Australia, our coastline will look very different and there could be a serious environmental disaster,” Dr Shaw said.

“We will see the impacts of climate change regardless, but if we put the policies and strategies in place now to curb it … it can make a huge difference over generations and decades to avoid something like this.”

“Otherwise things like our water sources, our infrastructure, our suburbs and way of life may have to change drastically.”

The Daily Telegraph has analysed the Coastal Risk Map to see just how much a five metre rise in sea levels would impact NSW - here’s what we found and how it will affect you.

HOW NSW WILL CHANGE IF SEA LEVELS RISE

Under the current worst case projections, if sea levels rise by 5 metres by 2150:

FAR NORTH COAST (Tweed Heads and beyond down to Coffs Harbour)

Most of Coffs Harbour will feel the impact of rising sea levels. Residents living in the vicinity of Boambee Beach out to North Boambee Valley and in and around Park Beach will be impacted, with water set to flow into the CBD.

Moonee Beach and significant sections of Woolgoolga and Emerald Beach will disappear or become a small set of islands as water flows above the shoreline. Other beachside areas like Red Rock, Wooli and Sandon will be overrun and become lakes or bays.

A major new lake system will be established flowing more than 60km inland from Yamba to Grafton if sea levels rise.

Areas like Grafton itself, Cowper, Townsend Harwood Island, Talumbi and Yamba and Wood Head will cease to exist, forming a large lake with a the village of South Arm in the centre.

A similar large harbour will be carved out between Evans Head and Lennox Head, swallowing up Ballina, Wardell, Broadwater, Coraki, Woodburn and as far down as Bungawalbin, with waterways also swelling to impact Lismore.

Directly along the coastline, the enclave of Byron Bay will be completely awash, as will every other settlement stretching up to Kingscliff and past the Queensland border.

Water will overtake Brunswick Heads, New Brighton, Pottsville, Hastings Point, Casuarina all the way up to Tweed Heads, flowing inland to inundate areas like Murwillumbah, and creating another large lake.

Down near Byron, Mullumbimby will also be severely impacted.

Erosion continues along Byron Bay coastline in 2020

 

Byron Bay storm erosion 31 July 2020 from BluecoastConsultingEngineers on Vimeo.

Echo NetDaily, 18 November 2020:

The state government is set to install sand bags at Clarkes Beach to protect the Beach Byron Bay cafe and Whites Cottage from the coastal erosion that has decimated the popular strip.

But it says the bags are just a temporary measure to give the building owners time to ‘reconfigure’ their premises, and that the cafe owner has been told to prepare for ‘future retreat’.

Management strategies were discussed at an urgent meeting held last month by the various state and local agencies who have responsibility for the Clarkes Beach area, including Council, Crown Lands and the Environment Department.

Clarkes has been severely affected by erosion over the past 12 to 18 months, with tonnes of sand stripped away exposing a rock shelf beneath. The beach is littered with uprooted pandanus trees, and the eroded dune line is now within metres of the Beach Byron Bay cafe.

There has also been further exposure of Aboriginal middens……

Representatives from a number of the agencies also expressed their views about the causes of the erosion; most were generally in agreement. This included an expert from the NSW Environment Department’s Sciences Group, who said the erosion was owing to a general reduction in the frequency of southerly swells, which played an important role in bringing sand to Clarkes Beach and Main Beach.

At the same time, there was an increase in the frequency of east and/or north east swells – patterns that have the effect of taking sand away from the beaches.

‘The net result over time is that the shoreline is undergoing a long-term trend of landward recession…’ the expert reportedly told the meeting.

‘Shoreline recession will also be influenced by sea level rise. An erosion period is occurring at the moment with no way to estimate when it will end. History tells us that the shorelines will eventually accrete [gather more sand]; however, when this will occur there is no way to know’.

[my yellow highlighting]

The Guardian, 20 October 2020:

Australia’s famous Byron Bay beach has been closed to swimmers and surfers as authorities carry out emergency sandbagging to prevent further damaging erosion.

Escalating erosion at Main Beach and Clarkes Beach in the northern New South Wales town has left a drop of several metres from the top of crumbling dunes down to the beach.

Max Pendergast, a 77-year-old local who has lived and surfed at Byron Bay his whole life, told Guardian Australia he had never seen the beaches in a worse condition.

“I’ve been through quite a few big cyclones, I’ve seen the sea come over the six-metre high dunes, but what’s happening now is an etching away of the beach,” he said.

“It looks pretty ugly right now, because a lot of the beach is just gone. It’s very bad.”

Pendergast said he noticed the beach deteriorate significantly over the past six months, and said he was concerned that if erosion continued waves would threaten units and the road along the beachfront.

“Not that long ago it was beautiful white sand all the way down to the water, but now it’s just rock, it really has eaten it away......

The climate change risk coastal towns and villages don't discuss enough

Financial Review, 15 November 2018:

Insurance giant IAG has warned a failure to reduce greenhouse gas emissions could result in a world that is "pretty much uninsurable", with poorer communities likely to bear the brunt of the effects.

In Australia, IAG said temperature increases of more than 3 degrees would expose greater swaths of Queensland to cyclones and flooding, while a rise of more than 4 degrees could make the risks to insurers prohibitive.

Timaru Herald, 26 May 2018, p.7:

Anyone now considering a coastal property should know what sea level rise is.

If they already own one, they shouldn't be surprised if buyers expect to know how it might affect them.

It's time to accept these properties may come with some risk, and let government and other agencies get on with the job of preparing without worrying about court battles over lost capital gains.

It's an inconvenient truth, but it appears that the value of flood- prone property will go down and many coastal towns will face a new threat.

The Sydney Morning Herald, 14 February 2018:

If any Australian company needs to come clean over its climate risks, it’s QBE.

Not just so shareholders can understand how secure (or not) their capital is as climate impacts intensify.

This is about Australians being able to see just how perilous our future has become without urgent action to cut greenhouse gas emissions.

Last October QBE said it expected 2017 to be the costliest year in the history of the global insurance industry, flagging a $US600 million ($767 million) hit to its pre-tax earnings. They weren't wrong, nor were they alone.

The triple-whammy of hurricanes Harvey, Irma and Maria hitting the US and Caribbean contributed to a record $US135 billion in payouts globally on natural disasters. Wildfires in California made things worse and, for Australian general insurers, Tropical Cyclone Debbie added to the pain.

Tom Herbstein, of Cambridge University’s insurance industry-funded project ClimateWise, summed it up in saying “climate change fundamentally challenges the existing insurance business model.”

And understandably there have been some drastic responses from within the industry. Hannover Re was even forced to sell its entire stock portfolio, worth €953 million ($A1.5 billion) , prompted by natural disaster claims.

Costly natural hazards are nothing new to QBE or indeed any of Australia’s big three general insurers.

Last year, individual large claims and natural hazards cost QBE $1.7 billion, or 15 per cent of the company’s net earned premium.

Compare this to the seven year average of 8.1 per cent to 2010, and you get an idea why QBE called it “unprecedented”.

Additionally, over the past decade, IAG under-provisioned for natural hazard claims by almost $1 billion while Suncorp under-provisioned by $1.9 billion.

It appears none of our general insurers are keeping up with the pace of climate change.

BACKGROUND

Excerpt from the Insurance Council of Australia’s Climate Change Policy:

The role of general insurance is to assist policyholders to recover from losses, such as those caused by extreme weather events. With expertise in risk management developed over hundreds of years of operation, general insurers play a critical role in communicating, managing and responding to the the risks that many policyholders face today, as well as how those risks may evolve under a changing climate.

It follows that the general insurance industry naturally supports community policy adjustments that will enhance resilience to extreme weather, as well as measures that may assist to reduce emissions.

Using the industry’s expertise in the pricing, transfer and management of risk, the following activities being undertaken by the industry are intended to assist policy-makers and communities to address the implications of climate change:

Maintain the strong prudential foundations underpinning the Australian market, to ensure that the industry continues to be able to respond to large disaster events when they occur.

Manage the commercial, individual and community-level risks posed by climate change via innovative risk-transfer solutions.

Ensure that risk-transfer solutions deliver competitive price signals, through risk based pricing, that assist communities and decision makers to recognise and adapt to current and emerging extreme weather risks.

Assist to increase community resilience over time by sharing industry expertise that will help policy decision makers and the community to:

Reduce exposures by making development control decisions for exposed locations that are appropriate for both the location and the planned life cycle of the development, accounting for the increased risk posed by the changing climate.

Reduce vulnerability to natural disasters by implementing localised defensive infrastructure where necessary to achieve an acceptable residual risk of damage to an exposed community.

Reduce vulnerability to natural disasters by improving building codes to ensure that built structures remain viable following predictable events over their planned life cycle, accounting for the increased risk posed by the changing climate.

Assist policy-makers to understand the long term economic implications of climate change, as well as the benefits of any appropriate emission mitigation schemes, by providing credible data on current exposures and vulnerabilities, as measured by the general insurance industry.

Assist to implement practical solutions to emission reduction strategies, through the consideration of risk-transfer products that incentivise solutions to be brought to market by other industries.

This policy was approved by the ICA's Board on August 4, 2016.

Coast Adapt, 2015:

Climate change threatens the viability of insurance in Australia and across the globe.

Despite a number of recent ‘quiet’ years, a trend of increasing losses is apparent in Australia and globally due to extreme weather events.

Insurers are covering at a loss some parts of Australia that are considered disaster-prone.

Sea Levels and the NSW Coastine in 2018: Ballina

“A recent study estimates that the pace of global sea-level rise has nearly tripled since 1990 (Dangendorf et al. 2017). More than 50% of the Australian coastline is vulnerable to erosion from rising sea levels….As sea levels continue to rise, coastal flooding during high sea level events will become more frequent and more severe (CSIRO and BoM 2015).”  [Climate Council, 2018, ICONS AT RISK: CLIMATE CHANGE THREATENING AUSTRALIAN TOURISM]]

New South Wales has est. 2,109kms of open coastline and 40 per cent of this is considered vulnerable to the effects of sea level rise.

Ballina is a coastal town in the NSW Northern River region. Its CBD is on the banks of the tidal Richmond River where it empties into the sea.

Sea level rise is something Ballina has been discussing for many years because for the Ballina community the evidence is right before residents’ eyes.

This was Tamar Street in the CBD in January 2018 at high tide.

Tamar Street, Ballina NSW, January 2018. Saltwater intrusion at high tide, Entrance to main bus station on the  left.

* Photograph via @Captainturtle

Coastal regions should note that last month saw second warmest April on record & also saw record-low Arctic, near-record-low Antarctic sea ice

“The average global temperature for April 2017 was 1.62 degrees F above the 20th-century average of 56.7 degrees, according to the analysis by scientists from NOAA’s National Centers for Environmental Information. This was the second highest for April in the 1880-2017 record, behind last year by 0.31 degrees.” [US National Oceanic and Atmospheric Administration (NOAA), May 2017]

The Northern Star, 24 May 2017:

INUNDATION THREAT: Areas in dark blue show the impact of a 0.74m seal level rise, while areas in light blue show a 2m rise.

NEW modelling has escalated the threat of sea level rises to the North Coast putting many more homes and valuable public infrastructure at risk.

Just four years after an initial report predicted a worst-case 0.74m sea level rise, rapid melting of the Antarctic and Greenland ice sheets have prompted scientists to publish a new report which predicts a 2m rise, although the chances of this worst-case scenario occurring are just 2%.

The research data provided by the US National Oceanic and Atmospheric Administration has been mapped into an interactive website published by Coastal Risk Australia, which puts the 2013 and 2017 predictions side by side.

Dark blue represents a 0.74m sea level rise and light blue represents the inundation spread with a 2m seal level rise, based

on US National Oceanic and Atmospheric Administration (NOAA) calculations

The Australian national mean temperature for April 2017 was 0.09 °C above average, according to the Australian Bureau of Meteorology.

With the continuation of warm conditions contributing to the sixth warmest January to April period on record.

When the ocean begins to flood a city.....

An object lesson for the Abbott Government and many communities on the east coast of Australia....

Quartz 30 June 2014:

The usual US partisan divisions over climate change were absent today in the state of Virginia, where Republican and Democratic officials met to discuss what to do about the threat of rising sea levels to the state. The proposals include the launch of a climate-change task force, which Virginia's Democratic governor will announce tomorrow. Christina DeConcini, government affairs director at the World Resources Institute, a research organization, told Quartz this is the first time to her knowledge that Republican leaders (very few of whom accept global warming is both real and man-made) and Democratic ones have come together to craft a policy on global warming.

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That's probably because Virginia is more vulnerable to storm-surge destruction than anywhere else on the US's east coast. Problems are particularly acute in Norfolk, Virginia's second-biggest city and home to the world's largest naval base; sea levels there are now 14.5 inches (37 cm) higher than they were in 1930—so high that parts of Norfolk flood when the moon is full. Sea levels are rising faster there than anywhere else along the coast, due to the vagaries of ocean currents:

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​Sewells Point is a peninsula off Norfolk.Natural Resources Defense Council

"A severe Category 2 or a Category 3 storm—if we were to receive a direct hit, almost all of the city would be underwater," Paul Fraim, Norfolk's mayor, told National Public Radio in 2012.

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This doesn't mean that high tide is lapping at Virginians' front doors. The main danger comes when storms pummel the coasts with huge waves, which are amplified by tidal forces. Here's an illustration of how high tides and storm surges, as they're called, differ:

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​"Virginia Hurricane Evacuation Guide"

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http://www.vaemergency.gov/sites/default/files/VirginiaStormSurge_Norfolk.pdf