New Zealand’s government has declared it will become the world’s first country to require its financial sector to report on climate risks.
A collaboration between Australian banks, insurers and climate scientists – the Climate Measurement Standards Initiative – has issued the nation’s first comprehensive framework to assess climate-related risks to buildings and critical infrastructure.
The first was HESTA, the industry super fund for health and community sector workers, in June. The second was CBus, the construction and mining industry super fund, last month. “The reality is that things are coalescing fast around us,” said Kristian Fok, CBus’ chief investment officer at the time.
While the superannuation industry remains very much in transition, analysis by ClimateWorks Australia and the Monash Sustainable Development Institute indicates a new determination among Australia’s 20 largest Registrable Superannuation Entity licensees to act on climate change risks.
These 20 licensees represent about 55% of all superannuation investments in Australia, worth a total of about A$2.7 trillion.
Along with the 2050 commitments by HESTA, CBus and UniSuper, another 13 funds are actively looking to reduce their portfolio’s emissions intensity. For example, Aware Super (formerly First State Super) announced in July it would divest from thermal coal miners and reduce emissions in its listed equities portfolio by at least 30% by 2023.
Only four of the 20 – Colonial First State, IOOF, Nulis and OnePath – still have no emissions reduction targets or activities.
This flurry of announcements reflects a changing context.
In the past, fund managers sometimes argued that, in a heavily regulated industry, their legal responsibilities prevented them from committing to emissions reductions. They were tasked, they said, with protecting their members’ finances, not guarding the environment.
Until about 2017, super funds tended to limit action to asking companies in which they owned shares to disclose their climate risks and to offering voluntary sustainable investment options to their members.
But since the Paris climate agreement in 2015, targets of net zero emissions by 2050 (or earlier) have been adopted by governments, businesses and investors. More than 100 countries and all Australian states and territories have net zero targets in place. So do some major companies, such as BHP and Qantas.
Many businesses now recognise the financial implications of global warming.
ANZ, for example, this month announced it expected the 100 biggest-emitting customers to have a plan to adapt to a low-carbon economy – something the bank’s chief executive, Shayne Elliot, said was simply “good old-fashioned risk management”.
This accords with the perspective of regulators, with Australian Prudential Regulation Authority regarding global warming not as a moral issue but one “distinctly financial in nature”.
This means asset managers are increasingly thinking about how more frequent and extreme weather events will devalue property and infrastructure. They are also thinking about the future worth of companies rusted to fossil fuels as the global economy shifts to net zero emissions.
Investors must also consider the possibility of litigation. For example, 24-year-old Brisbane council worker Mark McVeigh has taken the Retail Employees Superannuation Trust to court on the basis it has failed to protect his savings from the financial consequences of ruinous climate change.
Creating the new normal
Understandably, many funds are hesitant to commit to net zero emission portfolio targets without knowing how those targets might be achieved.
But by setting targets, super funds can create a norm that spurs investment in the ways and means to achieve those goals.
With the manifestations of that warming becoming ever more apparent, pressure will grow on super funds to make net zero pledges across their entire portfolios – and then to back these pledges with both interim commitments and detailed transition strategies.
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If we stopped oil, gas and coal extraction immediately – what would happen? What would we need to change about the way our economies and societies work in order to adjust to that resource no longer being available? Do alternatives already exist that mean it could be business as usual if we (governments and individuals) make changes, or would it mean a major adjustment to the way we live our lives?
It is not feasible to immediately stop extracting and using fossil fuels. The global economy, human health and livelihoods currently depend heavily on oil, coal and gas. But over time, we need to displace fossil fuels with low-carbon renewable energy sources.
The first priority should be on switching to renewable energy, not just for electricity but also for heating, cooling and transport fuels. It will be much harder to substitute fossils fuels used for chemical processing, such as the manufacture of plastics or fertiliser, but it is technically possible with biomass (organic material from plants and animals). After all, the hydrocarbons in coal, oil and gas were originally derived from biomass millions of years ago.
The aim of governments, local and national, should be to encourage reduced use of fossil fuels by supporting renewable energy systems.
Countries with good renewable resources can reach a significantly higher share. New Zealand, for example, now produces around 85% of its total electricity from renewable sources (including hydro, wind, solar and geothermal) without government intervention. But overall, renewable energy contributes only 40% of all energy demands in New Zealand, and far less globally.
There are many examples of how renewable energy can meet intensive industry demands, in New Zealand and elsewhere. New Zealand’s aluminium smelter uses electricity generated by the country’s largest hydro power station built underground at Lake Manapōuri. A steel mill in Sweden uses “green hydrogen”, produced by using renewable electricity to split water into hydrogen and oxygen.
Green hydrogen can also be used to displace natural gas for heating and cooking as well as for fuelling trucks, cars, boats and planes.
But the problem is fossil fuels remain relatively cheap, because the cost of their pollution isn’t usually factored in, and energy dense (there is more energy contained in a lump of coal than a piece of wood of a similar size). Displacement is not easy and will take time to allow those working in the fossil fuel industry to go through a “just transition” to work in other sectors.
Government intervention is often required for low-carbon options to increase their share in meeting total energy demands. But changing people’s behaviour around energy use is more challenging than deploying new low-carbon technologies to provide the same energy services.
We should not forget the additional benefits that come with a shift to low-carbon energy generation. More walking and cycling improves health, electric vehicles reduce local air pollution (compared with petrol and diesel vehicles) and using public transport and carrying more freight by rail can reduce traffic congestion. Other simple energy-saving measures – switching off lights, not wasting food – can all save money while lowering someone’s carbon footprint.
We have become a wasteful society, with consequences for the environment. Perhaps now is the time to make major adjustments to how we live before climate change impacts do it for us.
The fossil fuel lobby, led by the Minerals Council of Australia, seem pretty happy with the current system of environment laws. In a submission to a review of the Environment Protection and Biodiversity Conservation (EPBC) Act, it “broadly” supports the existing laws and does not want them replaced.
True, the group says the laws impose unnecessary burdens on industry that hinder post-pandemic economic recovery. It wants delays and duplication in environmental regulation reduced to provide consistency and certainty.
But for the fossil fuel industry to broadly back the current regime of environmental protection is remarkable. It suggests deep problems with the current laws, which have allowed decision-making driven by politics, rather than independent science.
So let’s look at the resources industry’s stance on environment laws, and what it tells us.
The Minerals Council’s submission calls for “eliminating or reducing duplication” of federal and state laws.
The fossil fuel lobby has long railed against environmental law – the EPBC Act in particular – disparaging it as “green tape” that it claims slows projects unnecessarily and costs the industry money.
On this, the federal government and the mining industry are singing from the same songbook. Announcing the review of the laws last year, the government flagged changes that it claimed would speed up approvals and reduce costs to industry.
Previous governments have tried to reduce duplication of environmental laws. In 2013 the Abbott government proposed a “one-stop shop” in which it claimed projects would be considered under a single environmental assessment and approval process, rather than scrutinised separately by state and federal authorities.
That proposal hit many political and other hurdles and was never enacted. But it appears to remain on the federal government’s policy agenda.
It’s true the federal EPBC Act often duplicates state approvals for mining and other activities. But it still provides a safety net that in theory allows the federal government to stop damaging projects approved by state governments.
The Commonwealth rarely uses this power, but has done so in the past. In the most famous example, the Labor party led by Bob Hawke won the federal election in 1983 and stopped the Tasmanian Liberal government led by Robin Gray building a major hydroelectric dam on the Gordon River below its junction with the Franklin River.
The High Court’s decision in that dispute laid the foundation for the EPBC Act, which was enacted in 1999.
In 2009 Peter Garrett, Labor’s then-federal environment minister, refused the Queensland Labor government’s proposed Traveston Crossing Dam on the Mary River under the EPBC Act due to an unacceptable impact on threatened species.
The Conversation put these arguments to the Minerals Council of Australia, and CEO Tania Constable said:
The MCA’s submission states that Australia’s world-leading minerals sector is committed to the protection of our unique environment, including upholding leading practice environmental protection based on sound science and robust risk-based approaches.
Reforms to the operation of the EPBC Act are needed to address unnecessary duplication and complexity, providing greater certainty for businesses and the community while achieving sound environmental outcomes.
But don’t change the current system much
Generally, the Minerals Council and other resources groups aren’t lobbying for the current system to be changed too much.
The groups support the federal environment minister retaining the role of decision maker under the law. This isn’t surprising, given a succession of ministers has, for the past 20 years, given almost unwavering approval to resource projects.
For example, in 2019 the then-minister Melissa Price approved the Adani coal mine’s groundwater management plan, despite major shortcomings and gaps in knowledge and data about its impacts.
When approached by The Conversation, the Minerals Council did not confirm it was referring to the New Acland project. Tania Constable said:
The case studies were submitted from a range of companies, and are representative of the regulatory inefficiency and uncertainty which deters investment and increases costs while greatly limiting job opportunities and economic benefits for regional communities from mining.
The New Acland mine expansion is on prime agricultural land on the Darling Downs, Queensland’s southern food bowl. Nearby farmers strongly opposed the project over fears of damage to groundwater, the creation of noise and dust, and climate change impacts.
But the Minerals Council fails to mention that since 2016, the mine has been building a massive new pit covering 150 hectares.
When mining of this pit began, the mine’s expansion was still being assessed under state and federal laws. Half of the pit was subsequently approved under the EPBC Act in 2017.
Based on my own research using satellite imagery and comparing the publicly available application documents, mining of West Pit started while Stage 3 of the mine was still being assessed under the EPBC Act. And after approval was given, mining was conducted outside the approved footprint.
The Conversation contacted New Hope Group, the company that owns New Acland mine, for comment, and they refuted this assertion. Chief Operating Officer Andrew Boyd said:
New Hope Group strongly deny any allegations that New Hope Coal has in any way acted unlawfully.
New Acland Coal had and still has all necessary approvals relating to the development of the pit Dr McGrath refers to. It is also not correct to say that the Land Court alerted the Department of its powers to act with regards to this pit.
The Department is obviously aware of its enforcement powers and was aware of the development of the pit well before 2018. Further, the Land Court in 2018 rejected Dr McGrath’s arguments and accepted New Acland Coal’s position that any issues relating to the lawfulness of the pit were not within the jurisdiction of the Land Court on the rehearing in 2018.
Accordingly, the lawfulness of the pit was irrelevant to the 2018 Land Court hearing.
Dr McGrath also fails to mention that his client had originally accepted in the original Land Court hearing (2015-2017) that the development of the pit was lawful only to completely change its position in the 2018.
State and federal environmental laws work in favour of the fossil fuel industry in other ways. “Regulatory capture” occurs when government regulators essentially stop enforcing the law against industries they are supposed to regulate.
This can occur for many reasons, including agency survival and to avoid confrontation with powerful political groups such as farmers or the mining sector.
In one apparent example of this, the federal environment department decided in 2019 not to recommend two critically endangered Murray-Darling wetlands for protection under the EPBC Act because the minister was unlikely to support the listings following a campaign against them by the National Irrigators Council.
Holes in our green safety net
Recent ecological disasters are proof our laws are failing us catastrophically. And they make the mining industry’s calls to speed-up project approvals particularly audacious.
A new United Nations report shows the world’s major fossil fuel producing countries, including Australia, plan to dig up far more coal, oil and gas than can be burned if the world is to prevent serious harm from climate change.
The report found fossil fuel production in 2030 is on track to be 50% more than is consistent with the 2℃ warming limit agreed under the Paris climate agreement. Production is set to be 120% more than is consistent with holding warming to 1.5℃ – the ambitious end of the Paris goals.
Australia is strongly implicated in these findings. In the same decade we are supposed to be cutting emissions under the Paris goals, our coal production is set to increase by 34%. This trend is undercutting our success in renewables deployment and mitigation elsewhere.
It reviewed seven top fossil fuel producers (China, the United States, Russia, India, Australia, Indonesia, and Canada) and three significant producers with strong climate ambitions (Germany, Norway, and the UK).
The production gap is largest for coal, of which Australia is the world’s biggest exporter. By 2030, countries plan to produce 150% more coal than is consistent with a 2℃ pathway, and 280% more than is consistent with a 1.5℃ pathway.
The gap is also substantial for oil and gas. Countries are projected to produce 43% more oil and 47% more gas by 2040 than is consistent with a 2℃ pathway.
Keeping bad company
Nine countries, including Australia, are responsible for more than two-thirds of fossil fuel carbon emissions – a calculation based on how much fuel nations extract, regardless of where it is burned.
Prospects for improvement are poor. As countries continue to invest in fossil fuel infrastructure, this “locks in” future coal, oil and gas use.
US oil and gas production are each projected to increase by 30% to 2030, as is Canada’s oil production.
Australia’s coal production is projected to jump by 34%, the report says. Proposed large coal mines and ports, if completed, would represent one of the world’s largest fossil fuel expansions – around 300 megatonnes of extra coal capacity each year.
The expansion is underpinned by a combination of ambitious national plans, government subsidies to producers and other public finance.
In Australia, tax-based fossil fuel subsidies total more than A$12 billion each year. Governments also encourage coal production by fast-tracking approvals, constructing roads and reducing royalty requirements, such as for Adani’s recently approved Carmichael coal mine in the Galilee Basin.
Ongoing global production loads the energy market with cheap fossil fuels – often artificially cheapened by government subsidies. This greatly slows the transition to renewables by distorting markets, locking in investment and deepening community dependency on related employment.
In Australia, this policy failure is driven by deliberate political avoidance of our national responsibilities for the harm caused by our exports. There are good grounds for arguing this breaches our moral and legal obligations under the United Nations climate treaty.
Cutting off supply
So what to do about it? As our report states, governments frequently recognise that simultaneously tackling supply and demand for a product is the best way to limit its use.
For decades, efforts to reduce greenhouse gas emissions have focused almost solely on decreasing demand for fossil fuels, and their consumption – through energy efficiency, deployment of renewable technologies and carbon pricing – rather than slowing supply.
While the emphasis on demand is important, policies and actions to reduce fossil fuels use have not been sufficient.
It is now essential we address supply, by introducing measures to avoid carbon lock-in, limit financial risks to lenders and governments, promote policy coherence and end government dependency on fossil fuel-related revenues.
Policy options include ending fossil fuel subsidies and taxing production and export. Government can use regulation to limit extraction and set goals to wind it down, while offering support for workers and communities in the transition.
Several governments have already restricted fossil fuel production. France, Denmark and New Zealand have partially or totally banned or suspended oil and gas exploration and extraction, and Germany and Spain are phasing out coal mining.
Australia is clearly a major contributor in the world’s fossil fuel supply problem. We must urgently set targets, and take actions, that align our future fossil fuel production with global climate goals.
Opposition Leader Bill Shorten announced last week that a federal Labor government would create a Just Transition Authority to overseee Australia’s transition from fossil fuels to renewable energy. This echoes community calls for a “fast and fair” energy transition to avoid the worst impacts of climate change.
Based purely on the technical lifetime of existing power stations, the Australian market operator predicts that 70% of coal-fired generation capacity will be retired in New South Wales, South Australia and Victoria by 2040. If renewables continue to fall in price, it could be much sooner.
We must now urgently decide what a “just” and “fair” transition looks like. There are many Australians currently working in the energy sector – particularly in coal mining – who risk being left behind by the clean energy revolution.
Coal communities face real challenges
The history of coal and industrial transitions shows that abrupt change brings a heavy price for workers and communities. Typically, responses only occur after major retrenchments, when it is already too late for regional economies and labour markets to cope.
Coal communities often have little economic diversity and the flow-on effects to local economies and businesses are substantial. It is easy to find past cases where as many as one third of workers do not find alternative employment.
We often hear about power stations, but there are almost 10 times as many workers in coal mining, where there is a much higher concentration of low and semi-skilled workers. The 2016 Census found almost half of coal workers are machinery operators and drivers.
The demographics of coal mining workers in Australia suggest natural attrition through early retirements will not be sufficient: 60% are younger than 45.
Mining jobs are well paid and jobs in other sectors are very unlikely to provide a similar income, so even under the best scenarios many will take a large pay cut.
Another factor is the long tradition of coal mining that shapes the local culture and identity for these communities. Communities are particularly opposed to change when they experience it as a loss of history and character without a vision for the future.
Lastly, the local environmental impacts of coal mining can’t be neglected. The pollution of land, water and air due to mining operations and mining waste have created brownfields and degraded land that needs remediation.
However, using the concept of energy justice, there are three main aspects which have to be considered for workers, communities and disadvantaged groups:
distributing benefits and costs equally,
a participatory process that engages all stakeholders in the decision making, and
recognising multiple perspectives rooted in social, cultural, ethical and gender differences.
A framework developed at the Institute for Sustainable Futures maps these dimensions.
A just transition requires a holistic approach that encompasses economic diversification, support for workers to transition to new jobs, environmental remediation and inclusive processes that also address equity impacts for marginalised groups.
The politics of mining regions
If there is not significant investment in transition plans ahead of coal closures, there will be wider ramifications for energy transition and Australian politics.
In Australia, electricity prices have been at the centre of the “climate wars” over the past decade. Even with the steep price rises in recent years, the average household still only pays around A$35 a week. But with the closure of coal power plants at Hazelwood and Liddell, Australia is really only just getting to the sharp end of the energy transition where workers lose jobs.
There are some grounds for optimism. In the La Trobe Valley, an industry wide worker redeployment scheme, investment in community projects and economic incentives appears to be paying dividends with a new electric vehicle facility setting up.
AGL is taking a proactive approach to the closure of Liddelland networks are forming to diversify the local economy. But a wider transition plan and investment coordinated by different levels of government will be needed.
Climate change became a topic of mainstream international concern in the early 1990s. For the first two decades of international climate cooperation, until the failed Copenhagen climate conference in 2009, the international environment movement embraced a more “technocratic” approach. Professionally-staffed environment groups made technical arguments aimed at persuading politicians and the public to adopt global climate treaties, national greenhouse gas emission reduction targets, and complex market-based policy mechanisms such as emissions trading schemes.
All of these things, if sufficiently stringent, would have been great if they were politically possible. But the groups advocating them were politically weak; they had few political resources. Consequently, in the competition to influence policy they were systematically outgunned by the fossil fuel industry.
Not only did the environment movement lack money and power over the economy, they lacked public support for their policy agenda. While public concern for climate change throughout this period was widespread, it was shallow. It was a political priority for few people, and fewer still were willing to take to the streets to demand strong, urgent action.
Why fossil fuels resonate
Compared with such ineffective climate activism, the present wave of anti-fossil fuel politics has an important advantage: it resonates better with ordinary people.
First, fossil fuels and associated infrastructure are readily understood by lay audiences. In contrast, concepts such as greenhouse gases, “2°C average warming”, and “350 ppm” are abstract, technical constructions not readily grasped by laypersons.
Surveys about energy sources in theUSandAustralia, for example, support the claim that fossil fuels are unpopular. In China, local air pollution caused by fossil fuels is one of the biggest public concerns. And casestudies from various countries indicatethepotential for proposed fossil fuel infrastructure to generate strong local opposition, social conflict, and wider media attention.
Third, targeting fossil fuels helps to personalize the causes of climate change. One of the reasons climate change is not psychologically salient to most people is that it is typically perceived to be an unintentional side-effect of the everyday actions of billions of people. This makes it hard for us to attribute blame.
Among anti-fossil fuel campaigns, the fossil fuel divestment movement aims most directly and explicitly to delegitemise the fossil fuel industry. Studiesshowthatthedivestmentmovementhas, in a very short time, had a revitalising effect on climate activism through the mobilisation of young people, and improved wider public discourse toward climate change action, among other beneficial effects.
Targeting fossil fuels is not the only way to build more successful movements around climate action. Campaigns providing a more positive vision around renewable energy, for example, have also been successful in mobilising grassroots support, and are a crucial component in contemporary climate activism. And successful grassroots mobilisation is not everything: elite politics and international relations also greatly affect climate policy.
But building wide and deep social movements committed to urgent climate action is a necessary element of the political task before us. As the rising tide of anti-fossil fuel activism shows, if campaigners work with the grain of ordinary human motivation, drawing on what we know about the psychology and sociology of social movements, then they are in with a fighting political chance.
For the third year in a row, global carbon dioxide emissions from fossil fuels and industry have barely grown, while the global economy has continued to grow strongly. This level of decoupling of carbon emissions from global economic growth is unprecedented.
Global CO₂ emissions from the combustion of fossil fuels and industry (including cement production) were 36.3 billion tonnes in 2015, the same as in 2014, and are projected to rise by only 0.2% in 2016 to reach 36.4 billion tonnes. This is a remarkable departure from emissions growth rates of 2.3% for the previous decade, and more than 3% during the 2000s.
Given this good news, we have an extraordinary opportunity to extend the changes that have driven the slowdown and spark the great decline in emissions needed to stabilise the world’s climate.
The slowdown in emissions growth has been primarily driven by China. After strong growth since the early 2000s, emissions in China have levelled off and may even be declining. This change is largely due to economic factors, such as the end of the construction boom and weaker global demand for steel. Efforts to reduce air pollution and the growth of solar and wind energy have played a role too, albeit a smaller one.
The United States has also played a role in the global emissions slowdown, largely driven by improvements in energy efficiency, the replacement of coal with natural gas and, to a lesser extent, renewable energy.
What makes the three-year trend most remarkable is the fact that the global economy grew at more than 3% per year during this time. Previously, falling emissions were driven by stagnant or shrinking economies, such as during the global financial crisis of 2008.
Developed countries, together, showed a strong declining trend in emissions, cutting them by 1.7% in 2015. This decline was despite emissions growth of 1.4% in the European Union after more than a decade of declining emissions.
Emissions from emerging economies and developing countries grew by 0.9% with the fourth-highest emitter, India, growing at 5.2% in 2015.
Importantly, the transfer of CO₂ emissions from developed countries to less developed countries (via trade of goods and services produced in places different to where they are consumed) has declined since 2007.
Deforestation and other changes in land use added another 4.8 billion tonnes of CO₂ in 2015, on top of the 36.3 billion tonnes of CO₂ emitted from fossil fuels and industry. This is a significant increase by 42% over the average emissions of the previous decade.
This jump in land use change emissions was largely the result of increased fires at the deforestation frontiers, particularly in Southeast Asia, driven by dry conditions brought by a strong El Niño in 2015-16. In general, though, long-term trends for emissions from deforestation and other land use change appear to be lower for the most recent decade than they were in the 1990s and early 2000s.
The carbon quota
When combining emissions from fossil fuels, industry, and land use change, the global economy released another 41 billion tonnes to the atmosphere in 2015, and will add roughly the same amount again this year.
We now need to turn this no-growth to actual declines in emissions as soon as possible. Otherwise, it will be a challenge to keep cumulative emissions below the level that would avoid a 2℃ warming, as required under the Paris Agreement.
As part of our carbon budget assessment, we estimate that cumulative emissions from 1870 (the reference year used by the Intergovernmental Panel on Climate Change to calculate carbon budgets) to the end of 2016 will be 2,075 billion tonnes of CO₂. The remaining quota to avoid the 2℃ threshold, assuming constant emissions, would be consumed at best in less than 25 years (with remaining quota estimates ranging from 450 to 1,050 billion tonnes of CO₂). Ultimately, we must reduce emissions to net zero to stabilise the climate.
We are strongly sympathetic to the need for a rapid global shift away from fossil fuels. But new modelling conducted independently and made publicly available by my colleague at the Understandascope, Josh Floyd, suggests that such a transition may face significant challenges.
Analyses of how to get to 100% renewable energy typically look at how future energy sources can supply enough energy to meet a given future demand.
This is what’s known as an “energy balance”. The high-quality work of Mark Diesendorf and his colleagues on the transition of Australia’s electricity supply to 100% renewables typifies such modelling.
But this approach doesn’t tell us what will happen to overall energy supply during the transition.
This new modelling suggests a significant decline in availability of overall energy services during the transition phase. This reflects the increased energy demand associated with the transition task itself.
Such an energy “trough” would significantly impact the economy during the transition. This has flow-on consequences for how to maintain the massive renewables roll-out.
What are net energy services?
To investigate what might happen to energy availability during transition, the model looks at “net energy services” at a global scale.
Net energy services are the total work and heat that energy sources – for instance solar photovoltaic (PV) systems or petroleum – make available to end users, minus the energy services required to provide that supply.
Petroleum requires energy services to find, produce, transport and refine it. Solar PV systems require energy services for mining raw materials, manufacturing, installation, replacement and so on. The net services are what remains available for all other purposes, such as heating buildings and moving goods and people.
A rapid, large-scale energy transition creates extra demands for energy services. This demand will compete with other economic activity.
The speed of transition matters
To start with, the model assumes that fossil fuels are phased out over about 50 years. Biomass, hydro and nuclear contributions are assumed roughly to double.
The model then attempts to maintain the net energy services to the global economy at the maximum level before the fossil fuel phase-out. To do this it uses electricity from onshore wind turbines and large-scale solar PV plants, buffered with lithium ion batteries.
The findings show that the faster the transition rate, the greater the energy services required by the transition task, and the lower the services available for other uses.
This is because of the time lag between energy investments and returns. It is exacerbated for sources where up-front energy investment is a relatively high proportion of the total life cycle, particularly so for solar PV.
A 50-year fossil-fuel phase-out represents a relatively modest transition rate. Even so, in the model’s baseline scenario, net energy services decline during that transition period by more than 15% before recovering.
And that recovery is not certain. The model doesn’t consider how this decline in energy services might affect the transition effort. If less energy services are available, then energy transition will come at the expense of other economic activity. That may impact the collective will to continue.
The cost of transition
In the model’s baseline scenario – phasing out fossil fuels over 50 years – wind and solar plants need to be installed at eight to ten times current rates by 2035.
Financially, this corresponds with capital investment in wind and solar PV plants plus batteries of around US$3 trillion per year (in 2015 dollars) and average lifetime capital cost in the order of US$5 trillion to US$6 trillion per year.
This implies that total expenditure on energy supply will increase its share of world spending, reducing scope for other expenditure. Compounding the decline in energy services during transition, this has potential to apply contractionary pressure to the global economy. This has implications in turn for financing and maintaining the political will for the renewables rollout.
What if it were possible to roll out renewables even faster? This could reduce the depth and duration of the decline, but not eliminate it. Again, due to the time lags involved, accelerating deployment in the short term takes energy services away, rather than adding them.
What does this mean?
Of course, this is “just” modelling. But good models can tell us a lot about the real world. If this modelling is right, and energy services fall and costs rise, we’ll have to complement building cleaner energy supply with other approaches.
The other key aspect of transition that we have control over is how much energy we expect to use. Usually discussions of transition focus on maintaining energy supply sufficient for a growing economy much like we see today – just with “clean” energy. But this is changing.
Growing numbers of analysts, business leaders and other prominent figures are calling for broader cultural change, as it becomes clearer that technological change alone is not enough to avoid climate catastrophe and myriad other consequences of energy-intensive consumer societies.
This is about more than efficiency. It is about a shift in our collective priorities and how we define progress, wellbeing and quality of living. Reducing energy demand within these redefined aspirations will markedly improve our prospects for successful transition.
The sea level changes for several reasons, including rising temperatures as fossil fuel burning increases the amount of greenhouse gases in the atmosphere. In a warming climate, the seas are expected to rise at faster rates, increasing the risk of flooding along our coasts. But until now we didn’t know what fraction of the rise was the result of human activities.
As the amount of greenhouse gases we are putting into the atmosphere continues to increase, we need to understand how sea level responds. This knowledge can be used to help predict future sea level changes.
Measuring sea level
Nowadays, we can measure the sea surface height using satellites, so we have an accurate idea of how the sea level is changing, both regionally and in the global mean.
Prior to this (before 1993), sea level was measured by tide gauges, which are spread unevenly across the world. As a result, we have a poorer knowledge of how sea level has changed in the past, particularly before 1960 when there were fewer gauges.
Nevertheless, the tide gauge measurements indicate that global mean sea level has increased by about 17 cm between 1900 and 2005.
What drives sea level rise?
The two largest contributors to rising seas are the expansion of the oceans as temperatures rise, loss of mass from glaciers and ice sheets, and other sources of water on land. Although we now know what the most important contributions to sea-level rise are, we did not know what is driving these changes.
Changes in sea level are driven by natural factors such as natural climate variability (for example El Niño), ongoing response to past climate change (regional warming after the Little Ice Age), volcanic eruptions, and changes in the sun’s activity.
Volcanic eruptions and changes in the sun affect sea level across years to decades. Large volcanic eruptions can cause a temporary sea-level fall because the volcanic ash reduces the amount of solar radiation reaching the ocean, thus cooling the ocean.
Humans have also contributed to sea level rise by burning fossil fuels and increasing the concentration of greenhouse gases in the atmosphere.
Separating the causes
We used climate models to estimate ocean expansion and loss of mass from glaciers and ice sheets for each of the individual factors responsible for sea level change (human and natural). To this we added best estimates of all other known contributions to sea level change, such as groundwater extraction and additional ice sheet contributions.
We then compared these model results to the observed global mean 20th century sea-level change to figure out which factor was responsible for a particular amount of sea level change.
Over the 20th century as a whole, the impact of natural influences is small and explains very little of the observed sea-level trend.
The delayed response of the glaciers and ice sheets to the warmer temperatures after the Little Ice Age (1300-1870 AD) caused a sea-level rise in the early 20th century. This explains much of the observed sea-level change before 1950 (almost 70%), but very little after 1970 (less than 10%).
The human factor
The largest contributions to sea-level rise after 1970 are from ocean thermal expansion and the loss of mass from glaciers in response to the warming from increasing greenhouse gas concentrations. This rise is partly offset by the impact of aerosols, which on their own would cause a cooling of the ocean and less melting of glaciers.
The combined influence of these two factors (greenhouse gases and aerosols) is small in the beginning of the century, explaining only about 15% of the observed rise. However, after 1970, we find that the majority of the observed sea-level rise is a direct response to human influence (nearly 70%), with a slightly increasing percentage up to the present day.
When all factors are considered, the models explain about three quarters of the observed rise since 1900 and almost all of the rise over recent decades (almost 90% since 1970).
The reason for this difference can be found either in the models or in the observations. The models could underestimate the observed rise before 1970 due to, for instance, an underestimated ice sheet contribution. However, the quality and number of sea level observations before the satellite altimeter record is also less.
Tipping the scales
Our paper shows that the driving factors of sea-level change have shifted over the course of the 20th century.
Past natural variations in climate were the dominant factor at the start of the century, as a result of glaciers and ice sheets taking decades to centuries to adapt to climate change.
In contrast, by the end of the 20th century, human influence has become the dominant driving factor for sea-level rise. This will probably continue until greenhouse gas emissions are reduced and ocean temperatures, glaciers and ice sheets are in equilibrium with climate again.
John will be on hand for an Author Q&A between 4 and 5pm AEST on Tuesday, April 12, 2016. Post your questions in the comments section below.