19/05/2020

(AU) Erosion From Surging Seas Threatens Roads, Homes And Beaches

Sydney Morning HeraldRoyce Millar | Benjamin Preiss | Miki Perkins

Surging seas have battered beaches and rattled communities along Victoria’s 2500 kilometre coastline since Easter, raising confronting questions about how to respond to rising oceans and rapid erosion.

High tides, big swells and storms have combined to pummel dunes and roads as anxious communities face the reality that homes and businesses may soon be at risk.


Coastal erosion in Inverloch, Victoria, is threatening businesses and homes.

At erosion hotspots like Inverloch, 150 kilometres south-east of Melbourne, and Apollo Bay 200 kilometres to the south-west, emergency defences including sand walls and fences have been swept away as debate intensifies over whether to defend assets or retreat to higher ground.

Despite the state’s ‘stay at home’ rules, imposed due to the coronaviruFs pandemic, anxious locals have gathered in numbers at beaches around Inverloch to watch waves tear at sand dunes, trees, roads and piers.

The main focus of concern is the low-lying road east toward Cape Paterson which has twice been closed as waves crashed onto bitumen and the sea-change dreams of nearby residents.

Last week traffic faced long delays as the government trucked in 7000 tonnes of boulders in a desperate bid to fortify the threatened stretch of road before winter. The new works came just weeks after an emergency 500-tonne rock wall was undermined by erosion.

A rock wall being built to try and halt erosion at the beach in Inverloch. Credit:Royce Millar

Locals are also anxious about the Inverloch surf life saving club which is under threat since erosion pushed the shoreline back 60 metres over the past eight years.

The latest defence for the surf club is a 70-metre emergency wall of ‘geotextile’ sandbags. While the bags are supposed to last up to 10 years, some have already been damaged by the relentless thrashing by waves and debris.

So dramatic is the erosion that the local conservation society has warned that the remaining sand dunes along the surf beach could be lost within 18 months, further exposing the coast road and nearby housing, and highlighting the much bigger challenge of sea level rise.

In September the Intergovernmental Panel on Climate Change warned that inaction on climate change would likely result in sea level rise of 1.1 metres by 2100 – up from the 2013 projection of more than 90 centimetres. Without action, the seas will be five metres higher by 2300.

While the IPCC says cutting emissions is the number one priority for dealing with rising sea levels, some change is already locked in. How we adapt is an increasingly urgent question.

As anxiety grows at Inverloch, so too has pressure for a massive rock wall along the entire length of the surf beach.

Experts query the wisdom of such walls, pointing out that they are incompatible with wide sandy beaches, and that erosion is made worse at either end.

Local environmentalists say the long-term solution is to tackle climate change. Meanwhile, a retreat to higher ground may be necessary.

Aileen Vening is a retired geography teacher who has spent almost a decade studying the causes and impacts of erosion along the Bass Coast. She is calling on her own community, and governments, to recognise that the dramatic erosion at Inverloch is not just a local phenomenon.

“We’ve got these issues everywhere on the coast. They’re not going to go away because we built a few rock walls here and there.”

Erosion at Inverloch is now threatening the coast road and nearby homes

While erosion at Inverloch is part of the natural cycle of shifting sand at the mouth of the Anderson Inlet, Bass Coast Shire has no doubt the extent of change is due in part to climate change and rising seas.

It is one of more than 30 Victorian councils to have declared a climate emergency since 2016.

“My view is that sea level is definitely rising, the climate is changing and the seasons are shifting,” said mayor Brett Tessari. “We have to do what we can to reverse some of the damage we’ve created.”

He acknowledges the “cries” from the community for a wall along the length of the sandy surf beach at Inverloch. But he is also aware that a rock wall would likely result in the disappearance of Inverloch surf beach.

The state government is now working on a longer-term solution for Inverloch through a local hazard assessment study in partnership with the council and community.

Decisions about defending or retreating, walls or beaches, are also especially topical at Apollo Bay which, like Inverloch, has been battered by angry seas since early April.

As The Age revealed in 2019, experts have proposed the inland re-routing of the heritage-listed Great Ocean Road at Apollo Bay amid warnings that it is at risk of being washed away in the next few years.

The government has resisted the re-routing push and has instead focused on building sea walls and other defences and supports.

Local surfer Peter Filmore said short-term government responses had failed to address the long-term reality of rising sea levels.

“Seventeen reports have been completed in the last 30 years on sand movements around Apollo Bay but no long-term planning is in place yet,” said Mr Filmore, also a member of the local Otway Forum.

He said governments were not being realistic about erosion, pointing to Colac Otway Shire’s plan for a $5 million coastal walking track from Apollo Bay to Skenes Creek – a track, he said, that was almost certain to be washed away.

Environmental lobby Friends of the Earth has worked closely with community groups along the Victorian coast.

Climate spokesman Leigh Ewbank said people were connecting the dots between burning fossil fuels, climate change and local impacts. “They say governments need to do more to tackle the climate crisis, it can’t just be Band-Aid fixes of dumping more rock and moving sand around.”

Environment Minister Lily D’Ambrosio said the government was assessing the erosion caused by recent “unexpected storm activity”.

She said coastal managers would install more warning signs and close sections of the foreshore as required.

Ms D’Ambrosio said the Victorian government had spent $60 million on a range of coastal and marine projects, including sand renourishment and reinforcement.

“Our precious coastline is facing significant climate challenges and we’re working hard to address this in the short and long term,” she said.

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(AU) Just How Hot Will It Get This Century? Latest Climate Models Suggest It Could Be Worse Than We Thought

The Conversation | 

AAP Image/Dave Hunt

Authors
Climate scientists use mathematical models to project the Earth’s future under a warming world, but a group of the latest models have included unexpectedly high values for a measure called “climate sensitivity”.

Climate sensitivity refers to the relationship between changes in carbon dioxide in the atmosphere and warming.

The high values are an unwelcome surprise. If they’re right, it means a hotter future than previously expected – warming of up to 7℃ for Australia by 2100 if emissions continue to rise unabated.

Our recent study analyses these climate models (named CMIP6), which were released at the end of last year, and what insights they give for Australia.

These models contain the latest improvements and innovations from some of the world’s leading climate modelling institutes, and will feed into the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report in 2021.

But the new climate sensitivity values raise the question of whether previous climate modelling has underestimated potential climate change and its effects, or whether the new models are overdoing things.

If the high estimate is right, this would require the world to make greater and more urgent emission cuts to meet any given warming target.

These higher climate sensitivity values point to the urgent need to cut our greenhouse gas emissions. Shutterstock

What is climate sensitivity?

Climate sensitivity is one of the most important factors for climate change, strongly influencing our planning for adaptation and mitigation of greenhouse gas emissions.

It’s a standardised measure of how much the climate responds when carbon dioxide concentrations in the atmosphere double. There are a few indices of climate sensitivity that the scientific community uses, and perhaps the most commonly used is “equilibrium climate sensitivity”.

We can estimate equilibrium climate sensitivity by raising carbon dioxide concentrations in models abruptly and then calculating the warming experienced after 150 years – when the atmosphere and ocean would return to a temperature balance.

In other words, giving the climate a “push” with more carbon emissions and waiting until it settles down into a new state.

The previous generation of models (CMIP5) had equilibrium climate sensitivity values between 2.1℃ to 4.7℃ global temperature change. The values for the latest models (CMIP6) are from 1.8℃ to 5.6℃.

This includes a cluster of models with sensitivity of 5℃ or more, a group of models within the previous range, and two models with very low values at around 2℃.

What this means for our future

Higher equilibrium climate sensitivity values mean a hotter future climate than previously expected, for any given scenario of future emissions.

We’ll see Australian temperature increase in a low and high emissions scenario projections (temperature relative to 1995-2014, range of models shown as coloured bands, observations as a black line). Author provided

According to these new models, Australian warming could crack more than 7℃ by 2100 under a scenario where greenhouse gas emissions continue to increase through the century.

These higher temperature changes are not currently presented in the national climate projections, as they didn’t occur under the previous generation of models and emission scenarios.

So what does this mean in practice?

Higher climate sensitivity means increases to heat extremes. It would mean we’ll see greater flow-on changes to other climate features, such as extreme rainfall, sea level rise, extreme heatwaves and more, reducing our ability to adapt.

High equilibrium climate sensitivity would also mean we need to make bigger cuts to our greenhouse gas emissions for a given global warming target. The Paris Agreement aims to keep global warming well under 2℃ since pre-industrial times.

Should we be worried?

These are credible models, representing the new generation versions of top performing modelling systems, developed over decades at high-ranking research institutions globally. Their results cannot be rejected out of hand just because we don’t like the answer.

But – we shouldn’t jump on this piece of evidence, throw out all others and assume the results from a subset of new models is the final answer.

The weight and credibility of each piece of evidence must be carefully assessed by the research community, and by scientists putting together the upcoming IPCC assessment.

We’re only just starting to understand the reasons for the high sensitivity in these models, such as how clouds interact with particles in the air.

And there are other lines of evidence underpinning the IPCC estimate of equilibrium climate sensitivity.

These include the warming seen since the last ice age around 20,000 years ago; measurements of warming seen over recent decades from greenhouse gases already emitted; and understanding different climate feedbacks from field experiments and observed natural variability. These other lines of evidence may not support the new model results.

Essentially, the jury is still out on the exact value of equilibrium climate sensitivity, high values can’t be ruled out, and the results from the new models need to be taken seriously.

In any case, the new values are a worrying possibility that no one wants, but one we must still grapple with. As researchers in one study conclude: “what scares us is not that the models’ [equilibrium climate sensitivity] is wrong […] but that it might be right”.

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How Our Brains Make It Hard To Solve Climate Change

Washington PostChris Mooney

Shahzeen Attari studies the psychology behind energy use and our views of the climate problem

A molten salt solar thermal tower situated in the Atacama Desert in Chile. (Tamara Merino Bloch for The Washington Post)

Shahzeen Attari, 38, is an associate professor at the School of Public and Environmental Affairs at Indiana University. She’s particularly focused on the way people perceive their personal energy use and the decisions they make in their daily lives, and how that impacts greenhouse gas emissions linked to a warming planet.

She published a paper earlier this year that examined how people understand the energy system in the United States and what they hoped it would look like in 2050. She and her team of researchers found that both liberals and conservatives expect the energy system of the future will be dominated by renewable sources, such as solar and wind.

This Q&A with Attari has been edited for brevity and clarity.

One of the things you found is that people really don’t understand a lot about energy in their lives or in society. Tell us about that work.
Attari: In general, people are able to rank appliances in terms of energy use, but they don’t have a clear understanding for what magnitude the energy differences might be. So they will know an air conditioner might be using more energy than a desktop or laptop computer, but they don’t know how much. And so I think that’s somewhat problematic.
But the good news is, in 2050, both conservatives and liberals want a severely decarbonized energy system. That’s really hopeful. But the question is, how do you get from where we are today to this 2050 vision?

Okay, so people don’t know how little the iPhone is drawing and how much the washer is drawing. What are the implications of that?
Attari: Since the 1980s, when people have been asked what is the single most effective thing you can do to conserve energy in your life, people have said … turn off the lights. 
Turning off the lights is great, but it’s not the most effective thing we can do … It’s actually the HVAC system. 
 So these misperceptions are really important because if I am a motivated individual and I wanted to decrease my carbon footprint or my energy footprint, I’m putting my effort into the wrong bucket.

What would you do to correct this?
Attari: One avenue of research that we’re looking at is trying to … provide novices with a “heuristic,” which is a simple rule. 
So we just told people, hey, large appliances that heat and cool use a lot more energy than you think. And that actually improves people’s perceptions. That actually makes them more accurate.

Are you of the belief that people can make pretty big differences within their four walls … for the whole world or not?
Attari: Are individuals enough? No, when it comes to climate change or energy use. Are individuals required? I think yes. … 
And I’m not just saying individuals decreasing their energy use, but individuals going from the personal, which is changing their energy use, to the societal.

Shahzeen Attari, an associate professor at the School of Public and Environmental Affairs at Indiana University, studies human behavior and climate change. (Paul H. O’Neill School of Public and Environmental Affairs/Indiana University)


Why is it that it’s not enough to just tell people pretty clearly that, your Energy Star appliance, your electric car, your solar panels, they’re all gonna save you lots of money.
Attari: You’re exactly right. Except we have this pernicious problem called “status quo bias.” We’re kind of stuck in our ways as social animals, so it’s very hard to get people to change.

You find people care a lot about the person who’s communicating to them [about climate change], and they don’t just want that person to be an expert. They want them to practice what they preach.
Attari: What we found was, the climate communicator’s carbon footprint really matters when it comes to credibility …

When a scientist gives a talk, usually the auditorium doesn’t fit more than 100. You’re not changing society when that happens.
Attari: In terms of modeling change, I completely agree with you. 
I don’t think climate scientists and climate communicators in the traditional sense are the best communicators for this. … We need people who are conservatives and liberals and people of religious and not religious [beliefs]. 
I mean, like all hands on deck because they’re getting really, really different swaths of the audience out there, the world out there.

You also found it was credibility enhancing for a communicator to be green, but you could go too far and be too green, and then people got angry at you. Is that right?
Attari: If you’re super extreme, that actually hurts you as a communicator … it puts people off, which makes sense. Like you’re too holier than thou, so I don’t want to listen to you or change my behavior.

What are some other blockages that are psychological to getting people to care about the climate or energy?
Attari: One pattern that I’m trying to understand how to break, is how do we bridge this growing partisan gap when it comes to a lot of different things, everything from who people choose to marry to the coronavirus response to climate change. 
So where are the points where we’re more similar than we are different? And what are the types of stories that can actually bridge those gaps?
The one bright spot is that both conservatives and liberals want this green future, which is the report that we just published, which was really surprising to us. 
Because everything we’ve seen in climate change over the past few decades has shown that there has been this growing gap when it comes to conservatives and liberals. 
But here we have data that show that both of them want a green future, which is dominated by renewables. That’s amazing.

What behavioral changes could be made by people, employers, organizations as we emerge from the pandemic that would help mitigate the effects of climate change?
Attari: We have made unprecedented changes to our behavior in the past few months. This tells us that when we face a problem, we can indeed activate, even while suffering large losses. … 
To deal with climate, I tend to think about behavioral changes that are personal, social and political. 
Examples of personal behaviors are decreasing your carbon footprint and making changes to your lifestyle that help to transition away from fossil fuels. 
These behaviors include getting your home energy from renewable sources (solar panels on your roof for example), going meat free, buying and using an electric vehicle, and switching to efficient home appliances. 
On the social side you can talk to friends and family members about climate change, you can discuss how you have made changes in your life and inspire others. 
On the political side, write to elected officials about why acting on climate change now is a priority for our community. Vote people into office that take climate change seriously and will act to transform our energy system.
I love what Arundhati Roy said: "Historically, pandemics have forced humans to break with the past and imagine their world anew. This one is no different. It is a portal, a gateway between one world and the next. 
"We can choose to walk through it, dragging the carcasses of our prejudice and hatred, our avarice, our databanks and dead ideas, our dead rivers and smoky skies behind us. 
"Or we can walk through lightly, with little luggage, ready to imagine another world. And ready to fight for it.”

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