A great start, but still not enough: why Victoria’s new climate target isn’t as ambitious as it sounds


Anita Foerster, Monash University; Alice Bleby, UNSW, and Anne Kallies, RMIT UniversityIn a great start towards net zero emissions by 2050, the Victorian Government recently released their Climate Change Strategy, committing to halving greenhouse emissions by 2030.

Victoria’s leadership, alongside commitments from other Australian states and territories, stands in stark contrast to the poor climate performance of our federal government.

But is it enough? Climate scientists are urging Australia to do more to reduce emissions and to do it quicker if we’re going to avert dangerous global warming. In fact, a recent Climate Council report claims achieving net zero emissions by 2050 is at least a decade too late.

We think the Victorian government has the legal mandate to do more. But we also recognise that ambitious climate action at the state level is hindered by a lack of commitment at the federal level.

Using law to drive emissions reductions

Victoria’s new strategy was developed under the Climate Change Act 2017, state legislation requiring the government to set interim emissions reduction targets on the way to net zero by 2050.

It spreads the job of achieving these targets across the economy, with different ministers responsible for pledging emissions reductions actions and reporting on progress over time.

Laws like this are emerging around the world to set targets and hold governments accountable for delivering on them. They’re a key tool to deliver on international commitments under the Paris Agreement to limit global warming to well below 2℃.

Although Australia has set a national target for emissions reduction under the Paris Agreement, it’s widely considered to be inadequate, and there’s currently no framework climate law at the national level. Independent Zali Steggall introduced such a bill in 2020, but the Morrison government hasn’t supported it.

Victoria’s new strategy lacks detail

Victoria’s Climate Change Strategy contains many exciting climate policy announcements, including:

  • renewable energy zones and big batteries in the regions
  • all government operations including schools and hospitals powered by 100% renewables by 2025
  • targets and subsidies for electric vehicle uptake
  • commitments to support innovation in hard-to-abate sectors such as agriculture.

It also recognises the need to phase out natural gas and accelerate Victoria’s renewable hydrogen industry.

These policies are designed to reduce emissions while supporting economic growth and job creation. Yet they are scant on detail.

There’s heavy reliance on achieving emissions reductions in the energy sector — arguably, this is the low-hanging fruit. Policies in transport and agriculture are far less developed, with no quantification of targeted emissions reductions to 2030.

Cows in a paddock
Victoria has committed to support innovation in hard-to-abate sectors such as agriculture.
Shutterstock

This makes it difficult to assess whether the sector pledges will drive enough change to achieve the government’s interim targets (ambitious or otherwise) and support a trajectory to net zero.

It has taken several years to develop the Climate Change Strategy. This makes the lack of detail and the undeveloped nature of some pledges a big concern.

There are also few safeguards in the Climate Change Act to ensure pledges add up to achieving targets, or that ministers across sectors deliver on them. Much depends on the political will of the government of the day.

Why Victoria’s targets aren’t enough

The Victorian Government proposes targets to reduce emissions by 28–33% on 2005 levels by 2025, and by 45–50% on 2005 levels by 2030.

The government claims these targets are ambitious. Compared to current federal government targets, this is true.




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However, the target ranges are lower than those recommended in 2019 by the Independent Expert Panel, established under the Climate Change Act to advise the government on target setting.

The panel recommended targets of 32–39% by 2025 and 45–60% by 2030 as Victoria’s “fair share” contribution to limiting warming to well below 2℃ in accordance with Paris Agreement goals. And it acknowledged these recommended ranges still wouldn’t be enough to keep warming to 1.5℃, in the context of global efforts.

Solar panels on a roof
Reducing emissions in the energy sector is low-hanging fruit.
Shutterstock

Ultimately, Victoria’s targets don’t match what scientists are now telling us about the importance of cutting emissions early to avoid the worst impacts of climate change.

A pragmatic approach or a missed opportunity?

In setting the targets, the state government has clearly taken a politically pragmatic approach.

The government claims the targets are achievable and suggests they would’ve set more ambitious targets if the federal government made a stronger commitment to climate action.

Yes, the current lack of climate ambition at the federal level in Australia is a very real constraint on progress in some areas such as energy, where a coordinated approach is crucial. But this shouldn’t outweigh aligning to best available science.

State governments have many regulatory, policy and economic levers at their disposal, with opportunities to drive significant change and innovation. And Victoria has already demonstrated strong progress in emissions reduction and renewables in the energy sector, easily meeting and exceeding previous targets.

Under the Climate Change Act, the Victorian Government will need to set new, more ambitious targets in five years.

But waiting five years goes against Victoria’s aim to lead the nation on climate action and contribute fairly to global efforts to mitigate global warming. More ambitious, science-aligned targets now would’ve been a valuable signal for industry and a sign of real climate leadership.

We need stronger laws

Without doubt, the new Climate Change Strategy is a significant step forward on an issue that’s plagued Australian politics for years. Victoria has showed framework climate laws can drive government action on climate change.




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But there are also opportunities to bolster the Climate Change Act by aligning targets to science, strengthening legal obligations to drive timely progress, and including an ongoing role for independent experts to advise on target setting and oversee progress.

Finally, it’s important to get on with the job at a federal level.

Zali Steggall’s Climate Change Bill 2020 picks up on best practice climate laws from around the world. It’s also supported by industry groups and investors.

Victoria’s experience suggests it’s surely time for Australia to take this important step.The Conversation

Anita Foerster, Senior Lecturer, Monash University; Alice Bleby, PhD Candidate, UNSW, and Anne Kallies, Senior Lecturer, RMIT University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Spot the difference: as world leaders rose to the occasion at the Biden climate summit, Morrison faltered


Lesley Hughes, Macquarie University and Will Steffen, Australian National UniversityPrime Minister Scott Morrison overnight addressed a much anticipated virtual climate summit convened by US President Joe Biden, claiming future generations “will thank us not for what we have promised, but what we deliver”.

But what will his government actually deliver?

Morrison’s speech was notable for its stark lack of ambition and a defensive tone at odds with the urgent, front-footed approach of other world leaders. He resisted the peer pressure to enter the global fold on climate action by setting clear goals, saying Australia made only “bankable” emissions-reduction commitments.

Morrison instead pointed to Australia’s “transformative technology targets”. As we will explain below, those targets are small, vague and certainly not “bankable”. And the spending commitments pale in comparison to the past and future cost of extreme weather in Australia.

Expectations of Australia heading into the summit were low – a fact perhaps reflected in the summit’s agenda. Morrison’s address was way down in the running order – he was 21st of 27 speakers. Biden was reportedly not in the room when Morrison spoke. And in an unfortunate glitch, Morrison’s microphone was on mute at the start of his speech.

The summit did deliver some major gains. There was palpable relief as Biden brought the US back to the table on global climate efforts, committing to an emissions-reduction target twice the ambition of Australia’s. Other nations including Japan, Canada and Britain also outlined major new commitments.

But sadly for Australians, the summit revealed the stark contrast in climate policy leadership between Morrison and his international peers.

Scott Morrison in front of Sydney harbour backdrop and Australian flags
The contrast on climate policy leadership between Scott Morrison and Joe Biden was on display at the summit.
Mick Tsikas/AAP

The world steps up

Biden opened the summit by emphasising the urgent need to keep global warming below 1.5℃ This century. Failing to do so, he said, would bring:

More frequent and intense fires, floods, droughts, heat waves, and hurricanes tearing through communities, ripping away lives and livelihoods, increasingly dire impacts to our public health […] We can’t resign ourselves to that future. We have to take action, all of us.

Biden committed the US to a 50-52% emissions reduction by 2030 compared with 2005 levels. Other notable emissions-reduction pledges included:

There were hopes Morrison would use the summit to announce Australia would finally join more than 100 countries to set an emissions target of net-zero by 2050. (Australia’s current emissions trajectory has us on track to get to net-zero in the year 2167).

But Morrison dashed those hopes early, telling world leaders: “For Australia, it is not a question of if or even by when for net-zero, but importantly how”.

He pointed to the government’s Technology Investment Roadmap, including A$20 billion to bring down the cost of clean hydrogen, green steel, energy storage and carbon capture. He also spoke of a goal to produce clean hydrogen for A$2 a kilogram, and his dream that Australia’s hydrogen industry would one day rival the scale of California’s Silicon Valley.




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Homes with solar panels on roof
Morrison spruiked Australia’s high uptake of rooftop solar.
Shutterstock

Will technology save us? Not likely

Earlier this week, Morrison set the scene for his address by announcing a suite of technology funding commitments. Let’s take a closer look at them.

On Wednesday Morrison announced A$540 million for regional hydrogen hubs and carbon-capture and storage (CCS) projects. Some A$275 million will be committed to seven hydrogen hubs in regional areas over five years – that’s about A$7.8 million per hub each year.

It’s hard to see this buying much more than a plan on a piece of paper. Further, there’s little detail on how much will be spent on clean vs dirty hydrogen – that is, hydrogen generated from renewables vs fossil fuels. However the proposed location of some of these hubs in fossil-fuel rich areas, such as the Latrobe Valley and Hunter Valley, does not bode well.

A further A$263.7 million over ten years will fund CCS projects. Since 2003, the Australian government has spent more than A$1 billion on CCS projects, with very little to show for it.

Globally, CCS has been criticised as unproven and expensive, simply designed to extend the life of fossil fuel industries.




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trucks carry coal through mine
CCS critics say it is simply a move to prop up fossil fuel industries.
Shutterstock

The third tranche of funding, announced on Thursday, is A$566 million for research partnerships with other countries for new technology such as green steel, small modular nuclear reactors and soil carbon storage. There was little detail in the announcement, so for now it remains rather hypothetical.

In sum, the government will spend a relatively small amount on hydrogen production and CCS, spread wafer thin in various regional areas (and at least some of it subsidising fossil fuels), plus hypothetical funding for research.

Compare this to the A$35 billion cost of extreme weather disasters in Australia between 2010 and 2019, as detailed in this Climate Council report.

More recently, the New South Wales government estimated the potential cost of last month’s devastating floods at A$2 billion. A report by the NSW Treasury estimated by 2061, future economic costs of climate impacts in four key risk areas (bushfires, sea level rise, heatwaves and agricultural production) could reach up to A$17.2 billion a year – and this is just for NSW.




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Debris washed up against bridge
The recent NSW floods caused $2 billion in damage, the state government says.
James Gourley/AAP

A tale of two leaders

Morrison told world leaders Australia would update its emissions-reduction target ahead of the Glasgow climate summit later this year. The current target – a 26-28% cut by 2030, based on 2005 levels – is broadly viewed as woefully inadequate.

Any increased ambition would be long overdue. However, more broadly, the contrast on climate policy between Morrison and Biden could not be clearer. Biden used the summit to tell world leaders:

Your leadership on this issue is a statement to the people of your nation and to the people of every nation, especially our young people, that we’re ready to meet this moment […] We really have no choice. We have to get this done.

Morrison, depressingly, showed little sign of hearing that message.The Conversation

Lesley Hughes, Professor, Department of Biological Sciences, Macquarie University and Will Steffen, Emeritus Professor, Fenner School of Environment & Society, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Is Malcolm Turnbull the only Liberal who understands economics and climate science – or the only one who’ll talk about it?


Darren England/AAP

Richard Denniss, Crawford School of Public Policy, Australian National UniversityYesterday, former Liberal prime minister Malcolm Turnbull was unceremoniously dumped as chair of the New South Wales government’s climate advisory board, just a week after being offered the role. His crime? He questioned the wisdom of building new coal mines when the existing ones are already floundering.

No-one would suggest building new hotels in Cairns to help that city’s struggling tourism industry. But among modern Liberals it’s patently heresy to ask how rushing to green light 11 proposed coal mines in the Hunter Valley helps the struggling coal industry.

Coal mines in the Hunter are already operating well below capacity and have been laying off workers in the face of declining world demand for coal, plummeting renewable energy prices and trade sanctions imposed by China. The problem isn’t a shortage of supply, but an abundance.

The simple truth is building new coal mines will simply make matters worse, especially for workers in existing coal mines that have already been mothballed or had their output scaled back.

coal mine in the Hunter Valley
Turnbull has called for a moratorium on new coal mines in the Hunter Valley, such as the one pictured above.
Dean Lewins/AAP

It gets worse. Once an enormous, dusty, noisy open cut coal mine is approved, the agriculture, wine, tourism and horse breeding industries – all major employers in the Hunter Valley – are reluctant to invest nearby. While building new coal mines hurts workers in existing coal mines, the mere act of approving new coal mines harms investment in job creation in the industries that offer the Hunter a smooth transition from coal.

The NSW planning department doesn’t have a plan for how many new coal mines are needed to meet world demand. Nor does it have a plan for how much expansion of rail and port infrastructure is required to meet the output of all the new mines being proposed.




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That’s why my colleagues and I recently called for a moratorium on new coal mines in the Hunter until such plans were made explicit. Just as you wouldn’t approve 1,000 new homes in a town where the sewerage system was already at capacity, it makes no sense to approve 11 new coal mines in a region that couldn’t export that much coal if it tried.

But if there’s one thing that defines the debate about coal in Australia, its that it makes no sense.

Just as it made no sense for then-treasurer Scott Morrison to wave a lump of coal around in parliament in 2017, it makes no sense for right-wing commentators to pretend approving new mines will help create jobs in coal mining. And it makes no sense for the National Party to ignore the pleas of farmers to protect their land from the damage coal mines do.

Scott Morrison with a lump of coal to Question Time in 2017.
Scott Morrison took a lump of coal to Question Time in 2017.
Lukas Coch/AAP

On the surface, Turnbull’s support for a pause on approving new mines while a plan is developed is old-fashioned centrism. It protects existing coal workers from new, highly automated mines, it protects farmers and it should make those concerned with climate change at least a bit happy. Win. Win. Win.

But there’s no room for a sensible centre in the Australian coal debate. And when someone even suggests the industry might not be set to grow, its army of loyal parliamentary and media supporters swing into action.

Labor’s Joel Fitzgibbon said Turnbull “wants to make the Upper Hunter a coal-mine-free zone”. The Nationals’ Matt Canavan suggested stopping coal exports was “an inhumane policy to keep people in poverty”. The head of the NSW Minerals Council suggested 12,000 jobs were at risk.

But of course, the opposite is true. Turnbull’s proposal to protect existing coal workers from competition from new mines would save jobs, not threaten them. He didn’t suggest coal mines be shut down tomorrow, or even early. And, given existing coal mines are running so far below capacity, his call has no potential to impact coal exports.




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Labor politicians need not fear: Queenslanders are no more attached to coal than the rest of Australia


Coal workers
Opening new coal mines won’t help save the jobs of existing coal workers.
Dan Himbrechts/AAP

Predictably, the Murdoch press ran a relentlessly misleading campaign in support of the coal industry and in opposition to their least favourite Liberal PM. But surprisingly, the NSW government rolled over in record time.

While the government might think appeasing the coal industry will play well among some older regional voters, they must know such kowtowing is a gift to independents such as Zali Steggall, and a fundamental threat to inner-city Liberals such as Dave Sharma, Jason Falinski and Trent Zimmerman.

The decision to dump Turnbull might have bought NSW Premier Gladys Berejiklian some respite from attacks from the Daily Telegraph. But such denial of economics and climate science will provide no respite for existing coal workers in shuttered coal mines or the agriculture and tourism industry that is looking to expand.

No doubt the National Party are pleased with their latest scalp. But it must be remembered this is the party that last year wanted to wage a war against koalas on behalf of property developers. Such political instincts might help the Nationals fend off the threat from One Nation in regional areas but it does nothing to retain votes in leafy Liberal strongholds that deliver most Liberal seats.




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The Conversation


Richard Denniss, Adjunct Professor, Crawford School of Public Policy, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: how particles ejected from the Sun affect Earth’s climate


Earth’s magnetic field protects us from the solar wind, guiding the solar particles to the polar regions.
SOHO (ESA & NASA)

Annika Seppälä


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz


When the Sun ejects solar particles into space, how does this affect the Earth and climate? Are clouds affected by these particles?

When we consider the Sun’s influence on Earth and our climate, we tend to think about solar radiation. We are acutely aware of the skin-burning dangers of ultraviolet, or UV, radiation.

But the Sun is an active star. It also continuously releases what is known as “solar wind”, made up of charged particles, largely protons and electrons, that travel at speeds of hundreds of kilometres per hour.

Some of these particles that reach Earth are guided into the polar atmosphere by our magnetic field. As a result, we can see the southern lights, aurora australis, in the southern hemisphere, and the northern equivalent, aurora borealis.

Aurora Australis
Aurora australis observed above southern New Zealand.
Shutterstock/Fotos593

This visible manifestation of solar particles entering Earth’s atmosphere is a constant reminder there is more to the Sun than sunlight. But the particles have other effects as well.




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Solar particles and ozone

When solar particles enter the atmosphere, their high energies ionise neutral atmospheric nitrogen and oxygen molecules, which make up 99% of the atmosphere. This “energetic particle precipitation”, named because it’s like a rain of particles from space, is a major source of ionisation in the polar atmosphere above 30km altitude — and it sets off a chain of reactions that produces chemicals that facilitate the destruction of ozone.

The impact of solar particles on atmospheric ozone was first observed in 1969. Since the early 2000s, thanks to new kinds of satellite observations, we have seen growing evidence that solar particles play an important part in influencing polar ozone. During particularly active times, when the Sun releases large amounts of particles into space, up to 60% of ozone at altitudes above 50km can be depleted. The effect can last for weeks.

Lower down in the atmosphere, below 50km, solar particles are important contributors to the year-to-year variability in polar ozone levels, often through indirect pathways. Here, solar particles again contribute to ozone loss, but a recent discovery showed they also help curb some of the depletion in the Antarctic ozone hole.

How ozone affects the climate

Most of the ozone in the atmosphere resides in a thin layer at altitudes of 20-25km — the “ozone layer”.

But ozone is everywhere in the atmosphere, from the Earth’s surface to altitudes above 100km. It is a greenhouse gas and plays a key role in heating and cooling the atmosphere, which makes it critical for climate.

In the southern hemisphere, changes in polar ozone are known to influence regional climate conditions.

Satellite image of Earth's atmosphere
Solar particles ionise nitrogen and oxygen molecules in the atmosphere, which leads to other chemical reactions that contribute to ozone destruction.
Shutterstock/PunyaFamily

Its depletion above Antarctica had a cooling effect, which in turn pulled the westerly wind jet that circles the continent closer. As the Antarctic hole recovers, this wind belt can meander further north and affect rainfall patterns, sea-surface temperatures and ocean currents. The Southern Annular Mode describes this north-south movement of the wind belt that circles the southern polar region.

Ozone is important for future climate predictions, not only in the thin ozone layer, but throughout the atmosphere. It is crucial we understand the factors that influence ozone variability, be it man-made or natural like the Sun.

The Sun’s direct influence

The link between solar particles and ozone is reasonably well established, but what about any direct effects solar particles may have on the climate?

We have observational evidence that solar activity influences regional climate variability at both poles. Climate models also suggest such polar effects link to larger climate patterns (such as the Northern and Southern Annular Modes) and influence conditions in mid-latitudes.

The details are not yet well understood, but for the first time the influence of solar particles on the climate system will be included in climate simulations used for the upcoming Intergovernmental Panel on Climate Change (IPCC) assessment.




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Solar weather has real, material effects on Earth


Through solar radiation and particles, the Sun provides a key energy input to our climate system. While these do vary with the Sun’s 11-year cycle of magnetic activity, they can not explain the recent rapid increase in global temperatures due to climate change.

We know rising levels of greenhouse gases in the atmosphere are pushing up Earth’s surface temperature (the physics have been known since the 1800s). We also know human activities have greatly increased greenhouse gases in the atmosphere. Together these two factors explain the observed rise in global temperatures.

What about clouds?

Clouds are much lower in the atmosphere than where most solar particles penetrate. Particles know as galactic cosmic rays (coming from the centre of our galaxy rather than the Sun) may be linked to cloud formation.

It has been suggested cosmic rays could influence the formation of condensation nuclei, which act as “seeds” for clouds. But recent research at the CERN nuclear research facility suggests the effects are insignificant.

This doesn’t rule out some other mechanisms for cosmic rays to affect cloud formation, but thus far there is little supporting evidence.The Conversation

Annika Seppälä, Senior Lecturer in Geophysics

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Paris Agreement 5 years on: big coal exporters like Australia face a reckoning



Shutterstock

Jeremy Moss, UNSW

On Saturday, more than 70 global leaders came together at the UN’s Climate Ambition Summit, marking the fifth anniversary of the Paris Agreement.

Prime Minister Scott Morrison was denied a speaking slot, in recognition of Australia’s failure to set meaningful climate commitments. Meanwhile, the European Union and the UK committed to reduce domestic emissions by 55% and 68% respectively by 2030.

As welcome as these new commitments are, the Paris Agreement desperately needs to be updated. Since it was passed, the production and supply of fossil fuels for export has continued unabated. And the big exporters — such as Norway, Canada, the US, Russia, Saudi Arabia and of course Australia — take no responsibility for the emissions created when those fossil fuels are burned overseas.

It’s time this changed. Australia is the world’s biggest coal exporter. And in 2019, emissions from fossil fuels exported by this nation, as well as the US, Norway and Canada, accounted for more than 10% of total world emissions, according to calculations from a research project on Australia’s carbon budget at the University of NSW, which I run. Exporting nations are not legally responsible for these offshore emissions, but their actions are clearly at odds with the climate emergency.

Business as usual

A 2019 UN report notes governments are planning to extract 50% more fossil fuels than is consistent with meeting a 2℃ target and an alarming 120% more than a 1.5℃ target, by 2030. Coal is the main contributor to this supply overshoot.

UN Secretary-General António Guterres urged all leaders to declare a climate emergency.

But rather than reducing their production of fossil fuels, many countries are doubling down and actually increasing supply. For example, in Australia, government figures show the greenhouse gas emissions from Australia’s exported fossil fuels increased by 4.4% between 2018 to 2019.

Australia is the world’s largest coal exporter and approved three new fossil fuel projects in recent months: the Vickery coal mine extension, Olive Downs and the Narrabri Gas Project

This is a worldwide trend. Let’s take Norway as another example. Norway gets the bulk of its electricity from hydropower and has partially divested its Government Pension Fund from some fossil fuels. Yet it’s also one of the largest exporters of greenhouse gases through its gas exports, behind Qatar and Russia.




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The situation is mirrored in the corporate world. Many large fossil fuel companies are trumpeting their emissions reductions targets while continuing to push for new fossil fuel mining projects. BHP, one of the world’s biggest miners, stated it is reducing its emissions, yet in October the company increased its stake in an oil field in the Gulf of Mexico.

Responsibility doesn’t stop at the border

What underpins this situation is an outdated “territorial” model of responsibility for climate harms. Governments and companies seem to think responsibility stops at the border, not with the overall livability of the global climate. Once the coal, oil and gas products are loaded onto ships, they are no longer our problem.

Unfortunately, the accounting rules of the United Nations, under the Paris Agreement, currently allow exporters to pass on responsibility for fossil fuel emissions.

We must move from this territorial model of responsibility to one that considers the whole chain of responsibility for climate harms.

So what should Australia, Canada, the US, Norway and other exporting countries do to address the over-supply of fossil fuels?

First, they need to acknowledge their responsibility, at least in part, for the emissions and associated harms caused by their exports. Allowing compensation and funding for mitigation to track the role played in the causal chain better attributes responsibility and places mitigation burdens back on the exporting countries.




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Future climate negotiations, such as in Glasgow in 2021 (COP26), need to adjust the scope of their targets to include robust reductions in the supply of fossil fuels in the next round of agreements.

Instead of just focusing on reducing demand, the process needs to function as a kind of “reverse OPEC” (the Organisation of the Petroleum Exporting Countries), where exporting countries are given ambitious phase-out targets for their fossil fuel exports.

Drastic emissions cuts needed

The 2020 Production Gap report notes global fossil fuel production will have to decrease by 6% a year between 2020-30 to meet a 1.5℃ target.

For Australia, this must mean we include the reduction in “exported emissions” as part of any net-zero target. Australia’s exported emissions are double our domestic emissions – a situation that cannot continue.

Top of the list of what’s needed, is the phasing out of generous subsidies for fossil fuel producers. The billions of dollars currently spent annually in Australia on subsidising and encouraging fossil fuel exports are simply not compatible with the aims and spirit of the Paris Agreement.




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Phasing out the supply of fossil fuels also needs to occur in a way that doesn’t just pay the current big suppliers to stop. Governments implementing a transition ought to think very carefully about how to fairly deploy scarce resources to ensure a just transition.

Last but not least, governments need to accept that the strong influence fossil fuel corporations wield over the political process is hindering global efforts to address climate change. The donations , rotation of industry staff to government positions and influence of fossil fuel lobby groups cannot lead to good decisions for the climate.

Placing a ban on such influence, particularly at future climate negotiations, would go a long way towards addressing the undue influence of the fossil fuel industry.

Until the fossil fuel export industry is subject to demanding targets, and made to accept responsibility for the emissions associated with their products, Earth will continue on its highly dangerous global warming trajectory.The Conversation

Jeremy Moss, Professor of Political Philosophy, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Biden says the US will rejoin the Paris climate agreement in 77 days. Then Australia will really feel the heat


Christian Downie, Australian National University

When the US formally left the Paris climate agreement, Joe Biden tweeted that “in exactly 77 days, a Biden Administration will rejoin it”.

The US announced its intention to withdraw from the agreement back in 2017. But the agreement’s complex rules meant formal notification could only be sent to the United Nations last year, followed by a 12-month notice period — hence the long wait.

While diplomacy via Twitter looks here to stay, global climate politics is about to be upended — and the impacts will be felt at home in Australia if Biden delivers on his plans.

Biden’s position on climate change

Under a Biden administration, the US will have the most progressive position on climate change in the nation’s history. Biden has already laid out a US$2 trillion clean energy and infrastructure plan, a commitment to rejoin the Paris agreement and a goal of net-zero emissions by 2050.

As Biden said back in July when he announced the plan:

If I have the honour of being elected president, we’re not just going to tinker around the edges. We’re going to make historic investments that will seize the opportunity, meet this moment in history.

And his plan is historic. It aims to achieve a power sector that’s free from carbon pollution by 2035 — in a country with the largest reserves of coal on the planet.

Biden also aims to revitalise the US auto industry and become a leader in electric vehicles, and to upgrade four million buildings and two million homes over four years to meet new energy efficiency standards.

Can he do it under a divided Congress?

While the votes are still being counted — as they should (can any Australian believe we actually need to say this?) — it seems likely the Democrats will control the presidency and the House, but not the Senate.

This means Biden will be able to re-join the Paris agreement, which does not require Senate ratification. But any attempt to legislate a carbon price will be blocked in the Senate, as it was when then-President Barack Obama introduced the Waxman-Markey bill in 2010.

In any case, there’s no reason to think a carbon price is a silver bullet, given the window to act on climate change is closing fast.




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What’s needed are ambitious targets and mandates for the power sector, transport sector and manufacturing sector, backed up with billions in government investment.

Fortunately, this is precisely what Biden is promising to do. And he can do it without the Senate by using the executive powers of the US government to implement a raft of new regulatory measures.

Take the transport sector as an example. His plan aims to set “ambitious fuel economy standards” for cars, set a goal that all American-built buses be zero emissions by 2030, and use public money to build half a million electric vehicle charging stations. Most of these actions can be put in place through regulations that don’t require congressional approval.

And with Trump out of the White House, California will be free to achieve its target that all new cars be zero emissions by 2035, which the Trump administration had impeded.

If that sounds far-fetched, given Australia is the only OECD country that still doesn’t have fuel efficiency standards for cars, keep in mind China promised to do the same thing as California last week.

What does this mean for Australia?

For the last four years, the Trump administration has been a boon for successive Australian governments as they have torn up climate policies and failed to implement new ones.

Rather than witnessing our principal ally rebuke us on home soil, as Obama did at the University of Queensland in 2014, Prime Minister Scott Morrison has instead benefited from a cosy relationship with a US president who regularly dismisses decades of climate science, as he does medical science. And people are dying as a result.

Obama on climate change at the University of Queensland.

For Australia, the ambitious climate policies of a Biden administration means in every international negotiation our diplomats turn up to, climate change will not only be top of the agenda, but we will likely face constant criticism.

Indeed, fireside chats in the White House will come with new expectations that Australia significantly increases its ambitions under the Paris agreement. Committing to a net zero emissions target will be just the first.

The real kicker, however, will be Biden’s trade agenda, which supports carbon tariffs on imports that produce considerable carbon pollution. The US is still Australia’s third-largest trading partner after China and Japan — who, by the way, have just announced net zero emissions targets themselves.

Should the US start hitting Australian goods with a carbon fee at the border, you can bet Australian business won’t be happy, and Morrison may begin to re-think his domestic climate calculus.

And what political science tells us is if international pressure doesn’t shift a country’s position on climate change, domestic pressure certainly will.




Read more:
Under Biden, the US would no longer be a climate pariah – and that leaves Scott Morrison exposed


With Biden now in the White House, it’s not just global climate politics that will be turned on its head. Australia’s failure to implement a serious domestic climate and energy policy could have profound costs.

Costs, mind you, that are easily avoidable if Australia acts on climate change, and does so now.The Conversation

Christian Downie, Australian Research Council DECRA Fellow, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

China just stunned the world with its step-up on climate action – and the implications for Australia may be huge



Lukas Coch/AAP

Hao Tan, University of Newcastle; Elizabeth Thurbon, UNSW; John Mathews, Macquarie University, and Sung-Young Kim, Macquarie University

China’s President Xi Jinping surprised the global community recently by committing his country to net-zero emissions by 2060. Prior to this announcement, the prospect of becoming “carbon neutral” barely rated a mention in China’s national policies.

China currently accounts for about 28% of global carbon emissions – double the US contribution and three times the European Union’s. Meeting the pledge will demand a deep transition of not just China’s energy system, but its entire economy.

Importantly, China’s use of coal, oil and gas must be slashed, and its industrial production stripped of emissions. This will affect demand for Australia’s exports in coming decades.

It remains to be seen whether China’s climate promise is genuine, or simply a ploy to win international favour. But it puts pressure on many other nations – not least Australia – to follow.

A man walking against an industrial skyline
It remains to be seen whether China will deliver on its climate pledge.
Da qing/AP

Goodbye, fossil fuels

Coal is currently used to generate about 60% of China’s electricity. Coal must be phased out for China to meet its climate target, unless technologies such as carbon-capture and storage become commercially viable.

Natural gas is increasingly used in China for heating and transport, as an alternative to coal and petrol. To achieve carbon neutrality, China must dramatically reduce its gas use.

Electric vehicles and hydrogen fuel-cell vehicles must also come to dominate road transport – currently they account for less than 2% of the total fleet.




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China must also slash the production of carbon-intensive steel, cement and chemicals, unless they can be powered by renewable electricity or zero-emissions hydrogen. One report suggests meeting the target will mean most of China’s steel is produced using recycled steel, in a process powered by renewable electricity.

Modelling in that report suggests China’s use of iron ore – and the coking coal required to process it into steel – will decrease by 75%. The implications for Australia’s mining industry would be huge; around 80% of our iron ore is exported to China.

It is critically important for Australian industries and policymakers to assess the seriousness of China’s pledge and the likelihood it will be delivered. Investment plans for large mining projects should then be reconsidered accordingly.

Conversely, China’s path towards a carbon neutral economy may open up new export opportunities for Australia, such as “green” hydrogen.

A bust road in China
To meet its pledge, China must decarbonise its transport system.
DIEGO AZUBEL/EPA

A renewables revolution

Solar and wind currently account for 10% of China’s total power generation. For China to meet the net-zero goal, renewable energy generation would have to ramp up dramatically. This is needed for two reasons: to replace the lost coal-fired power capacity, and to provide the larger electricity needs of transport and heavy industry.

Two factors are likely to reduce energy demand in China in coming years. First, energy efficiency in the building, transport and manufacturing sectors is likely to improve. Second, the economy is moving away from energy- and pollution-intensive production, towards an economy based on services and digital technologies.

It’s in China’s interests to take greater action on climate change. Developing renewable energy helps China build new “green” export industries, secure its energy supplies and improve air and water quality.

A solar array in China
A transition to renewable energy would improve air pollution in China.
Sam McNeil/AP

The global picture

It’s worth considering what factors may have motivated China’s announcement, beyond the desire to do good for the climate.

In recent years, China has been viewed with increasing hostility on the world stage, especially by Western nations. Some commentators have suggested China’s climate pledge is a bid to improve its global image.

The pledge also gives China the high ground over a major antagonist, the US, which under President Donald Trump has walked away from its international obligations on climate action. China’s pledge follows similar ones by the European Union, New Zealand, California and others. It sets an example for other developing nations to follow, and puts pressure on Australia to do the same.




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South Korea’s Green New Deal shows the world what a smart economic recovery looks like


The European Union has also been urging China to take stronger climate action. The fact Xi made the net-zero pledge at a United Nations meeting suggests it was largely targeted at an international, rather than Chinese, audience.

However, the international community will judge China’s pledge on how quickly it can implement specific, measurable short- and mid-term targets for net-zero emissions, and whether it has the policies in place to ensure the goal is delivered by 2060.

Much is resting on China’s next Five Year Plan – a policy blueprint created every five years to steer the economy towards various priorities. The latest plan, covering 2021–25, is being developed. It will be examined closely for measures such as phasing out coal and more ambitious targets for renewables.

Also key is whether the recent rebound of China’s carbon emissions – following a fall from 2013 to 2016 – can be reversed.

President Xi and President Trump
President Xi, left, has taken the high ground over the Trump-led US with its bold climate plan.
AP

Wriggle room

The 2060 commitment is bold, but China may look to leave itself wriggle room in several ways.

First, Xi declared in his speech that China will “aim to” achieve carbon neutrality, leaving open the option his nation may not meet the target.

Second, the Paris Agreement states that developed nations should provide financial resources and technological support to help developing countries reduce their emissions. China may make its delivery of the pledge conditional on this support.

Third, China may seek to game the way carbon neutrality is measured – for example, by insisting it excludes carbon emissions “embodied” in imports and exports. This move is quite likely, given exports account for a significant share of China’s total greenhouse gas emissions.

So for the time being, the world is holding its applause for China’s commitment to carbon neutrality. Like every nation, China will be judged not on its climate promises, but on its delivery.




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The Conversation


Hao Tan, Associate professor, University of Newcastle; Elizabeth Thurbon, Scientia Fellow and Associate Professor in International Relations / International Political Economy, UNSW; John Mathews, Professor Emeritus, Macquarie Business School, Macquarie University, and Sung-Young Kim, Senior Lecturer in International Relations, Discipline of Politics & International Relations, Macquarie School of Social Sciences, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: Sunspots do affect our weather, a bit, but not as much as other things



NASA

Robert McLachlan, Massey University


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz


Are we headed for a period with lower Solar activity, i.e. sunspots? How long will it last? What happens to our world when global warming and the end of this period converge?

When climate change comes up in conversation, the question of a possible link with the Sun is often raised.

The Sun is a highly active and complicated body. Its behaviour does change over time and this can affect our climate. But these impacts are much smaller than those caused by our burning of fossil fuels and, crucially, they do not build up over time.

The main change in the Sun is an 11-year Solar cycle of high and low activity, which initially revealed itself in a count of sunspots.

One decade of solar activity in one hour.

Sunspots have been observed continuously since 1609, although their cyclical variation was not noticed until much later. At the peak of the cycle, about 0.1% more Solar energy reaches the Earth, which can increase global average temperatures by 0.05-0.1℃.

This is small, but it can be detected in the climate record.

It’s smaller than other known sources of temperature variation, such as volcanoes (for example, the large eruption of Mt Pinatubo, in the Philippines in 1991, cooled Earth by up to 0.4℃ for several years) and the El Niño Southern Oscillation, which causes variations of up to 0.4℃.




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Climate explained: how volcanoes influence climate and how their emissions compare to what we produce


And it’s small compared to human-induced global warming, which has been accumulating at 0.2℃ per decade since 1980.

Although each 11-year Solar cycle is different, and the processes underlying them are not fully understood, overall the cycle has been stable for hundreds of millions of years.

A little ice age

A famous period of low Solar activity, known as the Maunder Minimum, ran from 1645 to 1715. It happened at a similar time as the Little Ice Age in Europe.

But the fall in Solar activity was too small to account for the temperature drop, which has since been attributed to volcanic eruptions.

Solar activity picked up during the 20th century, reaching a peak in the cycle that ran from 1954 to 1964, before falling away to a very weak cycle in 2009-19.

Bear in mind, though, that the climatic difference between a strong and a weak cycle is small.

Forecasting the Solar cycle

Because changes in Solar activity are important to spacecraft and to radio communications, there is a Solar Cycle Prediction Panel who meet to pool the available evidence.

Experts there are currently predicting the next cycle, which will run to 2030, will be similar to the last one. Beyond that, they’re not saying.

If activity picks up again, and its peak happened to coincide with a strong El Niño, we could see a boost in temperatures of 0.3℃ for a year or two. That would be similar to what happened during the El Niño of 2016, which featured record air and sea temperatures, wildfires, rainfall events and bleaching of the Great Barrier Reef.

The extreme weather events of that year provided a glimpse into the future. They gave examples of what even average years will look like after another decade of steadily worsening global warming.

A journey to the Sun

Solar physics is an active area of research. Apart from its importance to us, the Sun is a playground for the high-energy physics of plasmas governed by powerful magnetic, nuclear and fluid-dynamical forces.

The Solar cycle is driven by a dynamo coupling kinetic, magnetic and electrical energy.




Read more:
Explainer: how does our sun shine?


That’s pretty hard to study in the lab, so research proceeds by a combination of observation, mathematical analysis and computer simulation.

Two spacecraft are currently directly observing the Sun: NASA’s Parker Solar Probe (which will eventually approach to just 5% of the Earth-Sun distance), and ESA’s Solar Orbiter, which is en route to observe the Sun’s poles.

Hopefully one day we will have a better picture of the processes involved in sunspots and the Solar cycle.The Conversation

Exploring the 11-year Solar cycle.

Robert McLachlan, Professor in Applied Mathematics, Massey University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Marine life found in ancient Antarctica ice helps solve a carbon dioxide puzzle from the ice age



Chris Fogwill, Author provided

Chris Turney, UNSW and Chris Fogwill, Keele University

Evidence of minute amounts of marine life in an ancient Antarctic ice sheet helps explain a longstanding puzzle of why rising carbon dioxide (CO₂) levels stalled for hundreds of years as Earth warmed from the last ice age.

Our study
shows there was an explosion in productivity of marine life at the surface of the Southern Ocean thousands of years ago.




Read more:
Ancient Antarctic ice melt caused extreme sea level rise 129,000 years ago – and it could happen again


And surprisingly, this marine life once played a part regulating the climate. Hence, this finding has big implications for future climate change projections.

Walking into the past

Our research took us on a four-hour flight from Chile to the Weddell Sea, at the extreme southern end of the Atlantic Ocean, to land on an ice runway at a frigid latitude of 79° south.

Our Ilyshion aircraft landed on the Union Glacier (Antarctic Logistics and Expeditions).
Chris Turney, Author provided

The Weddell Sea is frequently choked with sea ice and has been hazardous to ships since the earliest explorers ventured south.

In 1914, the Anglo-Irish explorer Ernest Shackleton and his men became stuck here for two years, 1,000 kilometres from civilisation. They faced isolation, starvation, freezing temperatures, gangrene, wandering icebergs and the threat of cannibalism.

Surviving here is tough, as is undertaking science.




Read more:
What an ocean hidden under Antarctic ice reveals about our planet’s future climate


We spent three weeks in the nearby Patriot Hills, drilling through ice to collect samples.

Normally when scientists collect ice samples, they drill a deep core vertically down through the annual layers of snow and ice. We did something quite different: we went horizontal by drilling a series of shorter cores across the icescape.

That’s because the Patriot Hills is a fiercely wild place strafed by Weddell Sea cyclones that dump large snowfalls, followed by strong frigid winds (called katabatic winds) pouring off the polar plateau.

Those katabatic winds blowing hard.

As the winds blow throughout the year, they remove the surface ice in a process called sublimation. Older, deeper ice is drawn up to the surface. This means walking across the blue ice towards Patriot Hills is effectively like travelling back through time.

A walk across the blue ice is a walk back in time.
Matthew Harris, Keele University, Author provided

The exposed ice reveals what was happening during the transition from the last ice age around 20,000 years ago into our present warmer world, known as the Holocene.

The Antarctic Cold Reversal

As Earth was warming, carbon dioxide levels in the atmosphere were rising rapidly from around 190 to 280 parts per million.

But the warming trend wasn’t all one way.

Starting around 14,600 years ago, there was a 2,000 year-long period of cooling in the Southern Hemisphere. This period is called the Antarctic Cold Reversal, and is where CO₂ levels stalled at around 240 parts per million.

Why that happened was the puzzle, but understanding it could be crucial for improving today’s climate change projections.

Finding life in the ice

Over three weeks we battled the winds and snow to make a detailed collection of ice samples spanning the end of the last ice age.

We collected sample of ice to study later in the lab.
Chris Turney, Author provided

To our surprise, hidden in our ice samples were organic molecules – remnants of marine life thousands of years ago. They came from the cyclones off the Weddell Sea, which swept up organic molecules from the ocean surface and dumped them onshore to be preserved in the ice.

Antarctic ice, which forms from snowfall, usually only tells scientists about the climate. What’s exciting about finding evidence of lifẻ in ancient Antarctic ice is that, for the first time, we can reconstruct what was happening offshore in the Southern Ocean at the same time, thousands of years ago.

We found an unusual period, displaying high concentrations and a diverse range of marine microplankton. This increased ocean productivity coincided with the Antarctic Cold Reversal.

Melting sea ice in summer sustains marine life

Our climate modelling reveals the Antarctic Cold Reversal was a time of massive change in the amount of sea ice across the Southern Ocean.

Sea ice formed in winter melts in summer, and dumps nutrients into the ocean.
Shutterstock

As the world lurched out of the last ice age, the summer warmth destroyed large amounts of sea ice that had formed through winter. When the sea ice melts, it releases valuable nutrients into the Southern Ocean, and fuelled the explosion in marine productivity we found in the ice on the continent.

This marine life caused more carbon dioxide to be drawn from the atmosphere as it photosynthesised, similar to the way plants use carbon dioxide. When the marine life die they sink to the floor, locking away the carbon. The amount of carbon dioxide absorbed in the ocean was sufficiently large to register around the world.

What this mean for climate change today

Today, the Southern Ocean absorbs some 40% of all carbon put in the atmosphere by human activity, so we urgently need a better understand the drivers of this important part of the carbon cycle.




Read more:
The last ice age tells us why we need to care about a 2℃ change in temperature


Marine life in the Southern Ocean still plays an important role in regulating the amount of atmospheric carbon dioxide.

But as the world warms with climate change, less sea ice will be formed in polar regions. This natural carbon sink of marine life will only weaken, increasing global temperatures further.

It’s a timely reminder that while the Antarctic may seem remote, it’s impact on our future climate is closer and more connected than we might think.The Conversation

Chris Turney, Professor of Earth Science and Climate Change, Director of the Changing Earth Research Centre and the Chronos 14Carbon-Cycle Facility at UNSW, and Node Director of the ARC Centre of Excellence for Australian Biodiversity and Heritage, UNSW and Chris Fogwill, Professor of Glaciology and Palaeoclimatology, Head of School Geography, Geology and the Environment and Director of the Institute for Sustainable Futures, Keele University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We dug up Australian weather records back to 1838 and found snow is falling less often



State Library of South Australia

Joelle Gergis, Australian National University and Linden Ashcroft, University of Melbourne

As we slowly emerge from lockdown, local adventures are high on people’s wish lists. You may be planning a trip to the ski fields, or even the nearby hills to revel in the white stuff that occasionally falls around our southern cities after an icy winter blast.

Our new research explores these low-elevation snowfall events. We pieced together weather records back to 1838 to create Australia’s longest analysis of daily temperature extremes and their impacts on society.

These historical records can tell us a lot about Australia’s pre-industrial climate, before the large-scale burning of fossil fuels tainted global temperature records.

They also help provide a longer context to evaluate more recent temperature extremes.

We found snow was once a regular feature of the southern Australian climate. But as Australia continues to warm under climate change, cold extremes are becoming less frequent and heatwaves more common.

Heatwaves in Adelaide are becoming more common.
David Mariuz/AAP

Extending Australia’s climate record

Data used by the Bureau of Meteorology to study long-term weather and climate dates back to the early 1900s. This is when good coverage of weather stations across the country began, and observations were taken in a standard way.

But many older weather records exist in national and state archives and libraries, as well as local historical societies around the country.




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We analysed daily weather records from the coastal city of Adelaide and surrounding areas, including the Adelaide Hills, back to 1838. Adelaide is the Australian city worst affected by heatwaves, and the capital of our nation’s driest state, South Australia.

To crosscheck the heatwaves and cold extremes identified in our historical temperature observations, we also looked at newspaper accounts, model simulations of past weather patterns, and palaeoclimate records.

The agreement was remarkable. It demonstrates the value of historical records for improving our estimation of future climate change risk.

Weather journal of Adelaide’s historical climate held by the National Archives of Australia.
National Archives of Australia

‘Limpness to all mankind’

While most other historical climate studies have looked at annual or monthly values, the new record enabled us to look at daily extremes.

This is important, because global temperature increases are most clearly detected in changes to extreme events such as heatwaves. Although these events may only last a few days, they have very real impacts on human health, agriculture and infrastructure.

Our analysis focused on the previously undescribed period before 1910, to extend the Bureau of Meteorology’s official record as far as possible.

Using temperature observations, we identified 34 historical heatwaves and 81 cold events in Adelaide from 1838–1910. We found more than twice as many of these “snow days” by conducting an independent analysis of snowfall accounts in historical documents.

Almost all the events in the temperature observations were supported by newspaper reports. This demonstrated our method can accurately identify historical temperature extremes.

For example, an outbreak of cold air on June 22, 1908, delivered widespread snow across the hills surrounding Adelaide. The Express and Telegraph newspaper reported:

Many people made a special journey from Adelaide by train, carriage, or motor to revel in the unwonted delight of gazing on such a wide expanse of real snow, and all who did so felt that their trouble was amply rewarded by the panorama of loveliness spread out before their enraptured eyes.

Snowballing at Mount Lofty 29 August 1905.
Source: State Library of South Australia

From December 26-30, 1897, Adelaide was gripped by a heatwave that produced five days above 40℃. Newspapers reported heat-related deaths, agricultural damage, animals dying in the zoo, bushfires and even “burning hot pavements scorching the soles of people’s shoes”. As The Advertiser reported:

When the mercury reaches its “century” (100℉ or 37.6℃) there must be a really uncomfortable experience for everyone. One such day can be struggled with; but six of them in a fortnight, three in succession — that is a thing to bring limpness to all mankind.

On December 31, 1897, the South Australian Register wrote prophetically of future Australian summers:

May Heaven preserve us from being here when the “scorchers” try and add a few degrees to the total.

Newspaper account of a deadly heatwave published in the South Australian Register on Friday 31 December 1897.
National Library of Australia

A longer view

While Australia has a long history of hot and cold extremes, our extended analysis shows that their frequency and intensity is changing.

The quality of the very early part of the record is still uncertain, so the information from the 1830s and 1840s must be treated with caution. That said, there is excellent agreement with newspaper and other historical records.

Our research suggests low-elevation snow events around Adelaide have become less common over the past 180 years. This can be seen in both temperature observations and independent newspaper accounts. For example, snowfall was exceptionally high in the 1900s and 1910s — more than four times more frequent than other decades.




Read more:
Black skies and raging seas: how the First Fleet got a first taste of Australia’s unforgiving climate


We also found heatwaves are becoming more frequent in Adelaide. The decade 2010–19 has the highest count of heatwaves of any decade in the record. Although recent heatwaves are not significantly longer than those of the past, our analysis showed heatwaves of up to ten days are possible.

Previous Australian studies have identified an increase in extreme heat and a corresponding decrease in cold events. However, this is the longest analysis in Australia, and the first to systematically combine instrumental and documentary information.

Number of heatwaves identified in Adelaide from January 1838 to August 2019. No digitised temperature observations are available from 1 January 1848 – 1 November 1856, so these decades are shown in lighter shades.
Author supplied
Number of extreme cold days identified in Adelaide from January 1838 to August 2019. No digitised temperature observations are currently available from 1 January 1848 – 1 November 1856, so these decades are shaded grey.
Author supplied

Learning from the past

This study shows we can use historical weather records to get a better picture of Australia’s long-term weather and climate history. By using different sources of information, we can piece together the significant events in our climate history with greater certainty.

Historical records tell us about more than just exciting day trips of the past. They also hold the key to understanding impacts of extreme events, such as heat-related deaths or agricultural damage, in the future.

A better understanding of these pre-industrial extremes will help emergency management services better adapt to increased climate risk, as Australia continues to warm.




Read more:
Just how hot will it get this century? Latest climate models suggest it could be worse than we thought


The Conversation


Joelle Gergis, Senior Lecturer in Climate Science, Australian National University and Linden Ashcroft, Lecturer in climate science and science communication, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.