Christian Jakob, Monash University and Michael Reeder, Monash UniversityEight days ago, it rained over the western Pacific Ocean near Japan. There was nothing especially remarkable about this rain event, yet it made big waves twice.
First, it disturbed the atmosphere in just the right way to set off an undulation in the jet stream – a river of very strong winds in the upper atmosphere – that atmospheric scientists call a Rossby wave (or a planetary wave). Then the wave was guided eastwards by the jet stream towards North America.
Along the way the wave amplified, until it broke just like an ocean wave does when it approaches the shore. When the wave broke it created a region of high pressure that has remained stationary over the North American northwest for the past week.
This is where our innocuous rain event made waves again: the locked region of high pressure air set off one of the most extraordinary heatwaves we have ever seen, smashing temperature records in the Pacific Northwest of the United States and in Western Canada as far north as the Arctic. Lytton in British Columbia hit 49.6℃ this week before suffering a devastating wildfire.
What makes a heatwave?
While this heatwave has been extraordinary in many ways, its birth and evolution followed a well-known sequence of events that generate heatwaves.
Heatwaves occur when there is high air pressure at ground level. The high pressure is a result of air sinking through the atmosphere. As the air descends, the pressure increases, compressing the air and heating it up, just like in a bike pump.
Sinking air has a big warming effect: the temperature increases by 1 degree for every 100 metres the air is pushed downwards.
High-pressure systems are an intrinsic part of an atmospheric Rossby wave, and they travel along with the wave. Heatwaves occur when the high-pressure systems stop moving and affect a particular region for a considerable time.
When this happens, the warming of the air by sinking alone can be further intensified by the ground heating the air – which is especially powerful if the ground was already dry. In the northwestern US and western Canada, heatwaves are compounded by the warming produced by air sinking after it crosses the Rocky Mountains.
How Rossby waves drive weather
This leaves two questions: what makes a high-pressure system, and why does it stop moving?
As we mentioned above, a high-pressure system is usually part of a specific type of wave in the atmosphere – a Rossby wave. These waves are very common, and they form when air is displaced north or south by mountains, other weather systems or large areas of rain.
Rossby waves are the main drivers of weather outside the tropics, including the changeable weather in the southern half of Australia. Occasionally, the waves grow so large that they overturn on themselves and break. The breaking of the waves is intimately involved in making them stationary.
Importantly, just as for the recent event, the seeds for the Rossby waves that trigger heatwaves are located several thousands of kilometres to the west of their location. So for northwestern America, that’s the western Pacific. Australian heatwaves are typically triggered by events in the Atlantic to the west of Africa.
Another important feature of heatwaves is that they are often accompanied by high rainfall closer to the Equator. When southeast Australia experiences heatwaves, northern Australia often experiences rain. These rain events are not just side effects, but they actively enhance and prolong heatwaves.
What will climate change mean for heatwaves?
Understanding the mechanics of what causes heatwaves is very important if we want to know how they might change as the planet gets hotter.
We know increased carbon dioxide in the atmosphere is increasing Earth’s average surface temperature. However, while this average warming is the background for heatwaves, the extremely high temperatures are produced by the movements of the atmosphere we talked about earlier.
So to know how heatwaves will change as our planet warms, we need to know how the changing climate affects the weather events that produce them. This is a much more difficult question than knowing the change in global average temperature.
How will events that seed Rossby waves change? How will the jet streams change? Will more waves get big enough to break? Will high-pressure systems stay in one place for longer? Will the associated rainfall become more intense, and how might that affect the heatwaves themselves?
Explainer: climate modelling
Our answers to these questions are so far somewhat rudimentary. This is largely because some of the key processes involved are too detailed to be explicitly included in current large-scale climate models.
Climate models agree that global warming will change the position and strength of the jet streams. However, the models disagree about what will happen to Rossby waves.
From climate change to weather change
There is one thing we do know for sure: we need to up our game in understanding how the weather is changing as our planet warms, because weather is what has the biggest impact on humans and natural systems.
To do this, we will need to build computer models of the world’s climate that explicitly include some of the fine detail of weather. (By fine detail, we mean anything about a kilometre in size.) This in turn will require investment in huge amounts of computing power for tools such as our national climate model, the Australian Community Climate and Earth System Simulator (ACCESS), and the computing and modelling infrastructure projects of the National Collaborative Research Infrastructure Strategy (NCRIS) that support it.
We will also need to break down the artificial boundaries between weather and climate which exist in our research, our education and our public conversation.
Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.
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When we say there’s a scientific consensus that human-produced greenhouse gases are causing climate change, what does that mean? What is the Intergovernmental Panel on Climate Change and what do they do?
The Intergovernmental Panel on Climate Change (IPCC) provides the world’s most authoritative scientific assessments on climate change. It provides policymakers with regular assessments of the scientific basis of climate change, its impacts and risks, and options for cutting emissions and adapting to impacts we can no longer avoid.
The IPCC has already released five assessment reports and is currently completing its Sixth Assessment (AR6), with the release of the first part of the report, on the physical science of climate change, expected on August 9.
Each assessment cycle brings together scientists from around the world and many disciplines. The current cycle involves 721 scientists from 90 countries, in three working groups covering the physical science basis (WGI), impacts, adaptation and vulnerability (WGII) and mitigation of climate change (WGIII).
In each assessment round, the IPCC identifies where the scientific community agrees, where there are differences of opinion and where further research is needed.
IPCC reports are timed to inform international policy developments such as the UN Framework Convention on Climate Change (UNFCCC) (First Assessment, 1990), the Kyoto Protocol (Second Assessment, 1995) and the Paris Agreement (Fifth Assessment, 2013-2014). The first AR6 report (WGI) will be released in August this year, and its approval meeting is set to take place virtually, for the first time in the IPCC’s 30-year history.
This will be followed by WGII and WGIII reports in February and March 2022, and the Synthesis Report in September 2022 — in time for the first UNFCCC Global Stocktake when countries will review progress towards the goal of the Paris Agreement to keep warming below 2℃.
During the AR6 cycle, the IPCC also published three special reports:
- on global warming of 1.5℃ (2018)
- on oceans and the cryosphere in a changing climate (2019)
- on climate change and land (2019).
How the IPCC reaches consensus
IPCC authors come from academia, industry, government and non-governmental organisations. All authors go through a rigorous selection process — they must be leading experts in their fields, with a strong publishing record and international reputation.
Author teams usually meet in person four times throughout the writing cycle. This is essential to enable (sometimes heated) discussion and exchange across cultures to build a truly global perspective. During the AR6 assessment cycle, lead author meetings (LAMs) for Working Group 1 were not disrupted by COVID-19, but the final WGII and WGIII meetings were held remotely, bringing challenges of different time zones, patchy internet access and more difficult communication.
The IPCC’s reports go through an extensive peer review process. Each chapter undergoes two rounds of scientific review and revision, first by expert reviewers and then by government representatives and experts.
This review process is among the most exhaustive for any scientific document — AR6 WGI alone generated 74,849 review comments from hundreds of reviewers, representing a range of disciplines and scientific perspectives. For comparison, a paper published in a peer-reviewed journal is reviewed by only two or three experts.
The role of governments
The term intergovernmental reflects the fact that IPCC reports are created on behalf of the 193 governments in the United Nations. The processes around the review and the agreement of the wording of the Summary for Policymakers (SPM) make it difficult for governments to dismiss a report they have helped shape and approved during political negotiations.
Importantly, the involvement of governments happens at the review stage, so they are not able to dictate what goes into the reports. But they participate in the line-by-line review and revision of the SPM at a plenary session where every piece of text must be agreed on, word for word.
Acceptance in this context means that governments agree the documents are a comprehensive and balanced scientific review of the subject matter, not whether they like the content.
The role of government delegates in the plenary is to ensure their respective governments are satisfied with the assessment, and that the assessment is policy relevant without being policy prescriptive. Government representatives can try to influence the SPM wording to support their negotiating positions, but the other government representatives and experts in the session ensure the language adheres to the evidence.
Climate deniers claim IPCC reports are politically motivated and one-sided. But given the many stages at which experts from across the political and scientific spectrum are involved, this is difficult to defend. Authors are required to record all scientifically or technically valid perspectives, even if they cannot be reconciled with a consensus view, to represent each aspect of the scientific debate.
The role of the IPCC is pivotal in bringing the international science community together to assess the science, weighing up whether it is good science and should be considered as part of the body of evidence.
Aaron Simmons, University of New England; Annette Cowie, University of New England; Brian Wilson, University of New England; Mark Farrell, CSIRO; Matthew Tom Harrison, University of Tasmania; Peter Grace, Queensland University of Technology; Richard Eckard, The University of Melbourne; Vanessa Wong, Monash University, and Warwick Badgery, The University of MelbourneSoil carbon is in the spotlight in Australia. A key plank in the Morrison government’s technology-led emissions reduction policy, it involves changing farming techniques so soils store more carbon from the atmosphere.
Farmers can encourage and accelerate this process through methods that increase plant production, such as improving nutrient management or sowing permanent pastures. For each unit of atmospheric carbon they remove in this way, farmers can earn “carbon credits” to be sold in emissions trading markets.
But not all carbon credits are created equal. In one high-profile deal in January, an Australian farm sold soil carbon credits to Microsoft under a scheme based in the United States. We analysed the methodology behind the trade, and found some increases in soil carbon claimed under the scheme were far too optimistic.
It’s just one of several problems raised by the sale of carbon credits offshore. If not addressed, the credibility of carbon trading will be undermined. Ultimately the climate – and the planet – will be the loser.
What is soil carbon trading?
Plants naturally remove carbon dioxide (CO₂) from the air through photosynthesis. As plants decompose, carbon-laden organic matter is added to the soil. If more organic matter is added than is lost, soil carbon levels increase.
Carbon trading schemes require the increase in soil carbon levels to be measured. The measurement methods are well-established, but can be costly and complex because they involve collecting and analysing large numbers of soil samples. And different carbon credit schemes measure the change in different ways – some more robust than others.
The Australian government’s Emissions Reduction Fund has a rigorous approach to soil sampling, laboratory analysis and calculation of credits. This ensures only genuine removals of atmospheric carbon are rewarded, in the form of “Australian Carbon Credit Units”.
Farmers can choose other schemes under which to earn carbon credits, such as the US-based carbon offset platform Regen Network.
Regen Network’s method for estimating soil carbon largely involves collecting data via satellite imagery. The extent of physical on-the-ground soil sampling is limited.
Regen Network issues “CarbonPlus credits” to farmers deemed to have increased soil carbon stores. Farmers then sell these credits on the Regen Network trading platform.
‘A number of concerns’
It was Regen Network which sold Microsoft the soil carbon credits generated by an Australian farm, Wilmot Station. Wilmot is owned by the Macdoch Group, and other Macdoch properties have also claimed carbon credits under the Regen Scheme.
Regen Network should be applauded for making its methods and calculations available online. And we appreciate Regen’s open, collaborative approach to developing its methods.
However, we have reviewed their documents and have a number of concerns:
- the dry weight of soil in a known volume, also known as “bulk density”, is a key factor in calculating soil carbon stocks. Rather than bulk density being measured from field samples, it was calculated using an equation. We examined this method and determined it was far less reliable than field sampling
- Estimates of soil carbon were not adjusted for gravel content. Because gravel contains no carbon, carbon stock may have been overestimated
- The remote sensing used by Regen Network involved assessment of vegetation cover via satellite imagery, from which soil carbon levels were estimated. However, vegetation cover obscures soil, and research has found predictions of soil carbon using this method are highly uncertain.
Wilmot increased soil carbon, or “sequestration”, through changes to grazing and pasture management. The resulting rates of carbon storage calculated by Regen Network were extremely high – 7,660 tonnes of carbon over 1,094 hectares. This amounts to 7 tonnes of carbon per hectare from 2018 to 2019.
These results are not consistent with our experience of what is possible through pasture management. For example, the CSIRO has documented soil carbon increases of 0.1 to 0.3 tonnes of carbon per hectare per year in Australia from a range of methods to increase pasture production.
We believe inaccurate methods have led to the carbon increase being overestimated. Thus, it appears excess carbon credits may have been awarded.
Many carbon trading schemes apply rules to ensure integrity is maintained. These include:
- an “additionality test” to ensure the extra carbon storage in the soil would not have happened anyway. It would prevent, for example, farmers claiming credits for practices they adopted in the past
- ensuring sequestered carbon is maintained over time
- disallowing double-counting of credits – for example, by preventing a country claiming credits that have been sold offshore.
Responses to these claims from Regen Network and Macdoch Group can be found at the end of this article. A full response from Regen can also be found here.
Not in the national interest?
Putting aside the problems noted above, the offshore sale of soil carbon credits generated by Australian farmers raises other concerns.
Second, soil carbon does not have unlimited emissions reduction potential. The quantum of carbon that can be stored in each hectare of soil is constrained, and limited by factors such as land availability and climate change. So measures to increase soil carbon should not detract from society’s efforts to reduce emissions from fossil fuel use.
And third, ensuring carbon remains in soil long after it’s deposited is a challenge because soil microbes break down organic matter. Carbon credit schemes commonly manage this by requiring a “buffer” of unsold credits. If stored carbon is lost, farmers must relinquish credits from the buffer.
If the loss is greater than the buffer, credits must be purchased to make up the difference. This exposes farmers to financial risk, especially if carbon prices rise.
Getting it right
Soil carbon is a promising way for Australia to substantially reduce its emissions. But methods used to measure gains in soil carbon must be accurate.
Carbon markets must be regulated to ensure credit is awarded for genuine abatement, and risks to farmers are limited. And the extent to which offshore carbon markets prevent Australia from meeting its own obligations to reduce emissions should be clarified and managed.
Improving the integrity of soil carbon trading will have benefits beyond emissions reduction. It will also improve soil health and farm productivity, helping agriculture become more resilient under climate change.
Regen Network response
Regen Network provided The Conversation with a response to concerns raised in this article. The full nine-page statement provided by Regen Network is available here.
The following is a brief summary of Regen Network’s statement:
– Limited on-ground soil sampling: Regen Network said its usual minimum number of soil samples was not reached in the case of Wilmot Station, because historical soil samples – taken before the project began – were used. To compensate for this, relevant sample data from a different farm was combined with data from Wilmot.
“We understand the use of ancillary data does not follow best practice and our team is working hard to ensure future projects are run using a sufficient number of samples,” Regen Network said.
– Bulk density: Regen Network said the historical sample data from Wilmot did not include “bulk density” measurements needed to estimate carbon stocks, which required “deviations” from its usual methodology. However the company was taking steps to ensure such estimates in future projects “can be provided with higher degrees of accuracy”.
– Gravel content: Regen Network said lab reports for soil samples included only the weight, not volume, of gravel present. “Best sampling practice should include the gravel volume as an essential parameter for accurate bulk density measurements. We will make sure to address this in our next round of upgrades and appreciate the observation!” the statement said.
– Remote sensing of vegetation: Regen Network said it did not use vegetation assessment at Wilmot station. It tested a vegetation assessment index at another property and found it ineffective at estimating soil carbon. At Wilmot station Regen used so-called individual “spectral bands” to estimate soil carbon at locations where on-ground sampling was not undertaken.
– Sequestration rates at Wilmot: Regen Network said while it was difficult to directly compare local sequestration rates across climatic and geologic zones, the sequestration rates for the projects in question “fall within the relatively wide range of sequestration rates” reported in key scientific studies.
Regen Network said its methodology “provides a conservative estimate on the final number of credits issued”. Its statement outlines the steps taken to ensure soil carbon levels are not overestimated.
– Integrity safeguards: Regen Network said it employs standards “based both on existing standards of reputable programs […] and inputs from project developers, in order to come up with a standard that not only is rigorous but also practical”. Regen Network takes steps to ensure additionality and permanence of carbon stores, as well as avoid double counting of carbon credits generated through their platform.
A more detailed response from Regen Network can be found here.
Wilmot Station response
Wilmot Station provided the following response from Alasdair Macleod, chairman of Macdoch Group. It has been edited for brevity:
We entered into the deals with Regen Network/Microsoft because we wanted to give a hint of the huge potential that we believe exists for farmers in Australia and globally to sequester soil carbon which can be sold through offset markets or via other methods of value creation.
Whilst we recognise that the soil carbon credits generated on the Macdoch Group properties in the Regen Network/Microsoft deal will not be included in Australia’s national carbon accounts, it is our hope that over time the regulated market will move towards including appropriately rigorous transactions such as these in some form.
At the same time we have also been working closely with the Australian government, industry organisations, academia and other interested parties on Macdoch Group properties to develop appropriate soil carbon methodologies under the government’s Climate Solutions Fund.
This is because carbon measurement methodologies are an evolving science. We have always acknowledged and will welcome improvements that will be made over the coming years to the methodologies utilised by both the voluntary and regulated markets.
In any event it has become clear that there is huge demand from the private sector for offset deals of this nature and we will continue to work towards ensuring that other farmers can take advantage of the opportunities that will become available to those that are farming in a carbon-friendly fashion.
Aaron Simmons, Adjunct Senior Research Fellow, University of New England; Annette Cowie, Adjunct Professor, University of New England; Brian Wilson, Associate Professor, University of New England; Mark Farrell, Principal Research Scientist, CSIRO; Matthew Tom Harrison, Associate Professor of Sustainable Agriculture, University of Tasmania; Peter Grace, Professor of Global Change, Queensland University of Technology; Richard Eckard, Professor & Director, Primary Industries Climate Challenges Centre, The University of Melbourne; Vanessa Wong, Associate Professor, Monash University, and Warwick Badgery, Research Leader Pastures an Rangelands, The University of Melbourne
Peter Christoff, The University of MelbourneResurrected Nationals leader Barnaby Joyce is back in the saddle, facing backwards. His determination to prevent the Morrison government from adopting a target of net-zero greenhouse emissions by 2050 will again delay the renovation of Australia’s climate policy.
The Nationals’ leadership spill reportedly followed growing disquiet about Morrison’s slow pivot towards a net-zero by 2050 goal. Many Nationals MPs have indicated they don’t back the target, and Joyce says he will be “guided by the party room” on the issue.
If Morrison eventually gets the 2050 target past Joyce and passed by the joint party room, there will be little cause for celebration. In fact, the achievement will be as exciting as watching a vaudeville magician wrench an old rabbit out of a moth-eaten hat.
Australia’s premiers will yawn in unison. Every state and territory in the country has already adopted this target, or better. Yet at the end of the day, net-zero by 2050 is a risky and inadequate goal, especially for wealthy nations such as Australia.
A target is nothing without a plan to get there
All G7 states and 11 G20 members are aiming for net-zero emissions by mid-century. These include the United Kingdom, Japan, Canada, Germany, France, the Republic of Korea, Italy, the European Union, Argentina and the United States. China, the world’s largest emitter, has committed to net-zero by 2060.
However, as international environment law expert Professor Lavanya Rajamani has argued, net-zero targets should not automatically be applauded. First, they should be checked for their credibility, accountability and fairness. On these measures, a net-zero by 2050 target for Australia is nothing to cheer.
Why? First, because a target is nothing without an effective strategy to get there – something Australia is sorely lacking.
To successfully achieve net-zero emissions by 2050, tough short- and medium-term targets are essential to staying on track. Victoria, for example, has pledged to halve carbon emissions by 2030. The UK is aiming for a 78% reduction by 2035, reflecting its confidence in existing and emerging technologies.
The Morrison government’s 2030 target – a 26-28% reduction below 2005 emissions levels – is not credible. Experts say a 2030 target of between 50% and 74% is needed to put Australia in line with keeping warming below 2℃ and 1.5℃ respectively – the goals of the Paris Agreement.
Reaching net-zero requires substantial government funding and tax relief for investors in renewable technologies. Morrison’s announcement of an additional A$540 million for new technologies is insufficient and partly misdirected.
For instance, the government is investing in carbon capture and storage. As others have argued, the technology is increasingly commercially unviable and encourages further fossil fuel use.
2050 goal is risky business
Even if Australia adopted a goal of net-zero by 2050, and measures to get there comfortably, the target is risky.
In 2018, the Intergovernmental Panel on Climate Change (IPCC) released a report on the potentially catastrophic impacts of exceeding 1.5℃ global warming. In the same report it established the idea of “net zero” as a global aim, saying achieving the target by 2050 was needed to stay below that warming threshold.
The IPCC described the emissions-reduction pathways required, but failed to emphasise crucial assumptions underlying them. Most depended on “negative emissions” – drawing down carbon from the atmosphere.
Many of those presumed drawdown measures involve land use measures that potentially threaten biodiversity or food security, for instance by requiring farmland and virgin forests to be used for growing “carbon crops”. Others involve geo-engineeering technologies which are yet to be tested or proven safe at scale.
It’s a risky strategy to avoid rapid, substantial and real emissions cuts in favour of gradual mitigation pathways that rely on such future carbon drawdown. It locks us into technologies which are problematic or don’t yet exist. To limit these risks, Australia must aim for net-zero well before 2050, predominantly via actual emissions cuts.
A matter of fairness
The matter of equity is another where policymakers have been inattentive to nuance. The undifferentiated call for net-zero by 2050 shifts the burden and costs of effort onto poorer countries. No wonder so many developed countries have been happy to adopt it!
The United Nations Framework Convention on Climate Change, the Kyoto Protocol and the Paris Agreement each require developed countries to cut emissions faster than poorer countries – and to assist poorer countries in their efforts. This recognises the fact developed nations are largely responsible for global warming, and have the wealth and technological capacities to act.
Developing nations such as India, Pakistan and Bangladesh, as well as those in Southeast Asia, Latin America, the Pacific and Africa, are mostly below global average wealth. Forcing them to meet the same net-zero timeframe as rich nations is patently unfair.
And for the international community to achieve even the 2050 goal, China – a global emissions giant – must increase its ambition to at least net-zero by 2050 (rather than its current 2060 timeframe).
It’s clear that rich developed countries must both aim for net-zero emissions well before 2050, and provide climate finance to assist poorer countries to do the same. Anything less will almost certainly guarantee Earth overshoots an already risky target.
Australia, given its wealth and technological means, must certainly aim for net-zero well before 2050. A report in April this year suggested reaching net-zero in 2035, to make a “fair and achievable contribution to the global task” and given our vulnerability to extreme weather.
The issue of climate finance was on the agenda at this month’s G7 summit, but critics say the final commitment – meeting an overdue spending pledge of US$100 billion a year – is inadequate considering the urgency of the task.
Just months out from a crucial UN climate summit in Glasgow in November, Scott Morrison is caught in a bind. On the global stage, he’s under increasing pressure to commit to a net-zero emissions target or face carbon tariffs. At home, he’s forced to assuage a minor coalition partner now led by a man who will reportedly push for a new coal-fired power station, and for agriculture – and potentially mining – to be exempt from emissions targets.
The looming general election will test whether rural voters are prepared to endure Joyce’s climate antics or will swing to savvy independents. And it remains to be seen whether urban voters will tolerate a prime minister whose transactional politics leaves Australia increasingly exposed at home and abroad.
Yuanyuan Huang, CSIRO and Yingping Wang, CSIROPeatlands, such as fens, bogs, marshes and swamps, cover just 3% of the Earth’s total land surface, yet store over one-third of the planet’s soil carbon. That’s more than the carbon stored in all other vegetation combined, including the world’s forests.
But peatlands worldwide are running short of water, and the amount of greenhouse gases this could set loose would be devastating for our efforts to curb climate change.
Specifically, our new research in Nature Climate Change found drying peatlands could release an additional 860 million tonnes of carbon dioxide into the atmosphere every year, by around 2100. To put this into perspective, Australia emitted 539 million tonnes in 2019.
To stop this from happening, we need to urgently preserve and restore healthy, water-logged conditions in peatlands. These thirsty peatlands need water.
Peatlands are like natural archives
Peatlands are found across the world: the arctic tundra, coastal marshes, tropical swamp forests, mountainous fens and blanket bogs on subantarctic islands.
They’re characterised by having water-logged soil filled with very slowly decaying plant material (the “peat”) that accumulated over tens of thousands of years, preserved by the low-oxygen environment. This partially decomposed plant debris is locked up in the soils as organic carbon.
Peatlands can act like natural archives, letting scientists and archaeologists reconstruct past climate, vegetation, and even human lives. In fact, an estimated 20,500 archaeological sites are preserved under or within peat in the UK.
As unique habitats, peatlands are home for many native and endangered species of plants and animals that occur nowhere else, such as the white-bellied cinclodes (Cinclodes palliatus) in Peru and Australia’s giant dragonfly (Petalura gigantea), the world’s largest. They can also act as migration corridors for birds and other animals, and can purify water, regulate floods, retain sediments and so on.
But over the past several decades, humans have been draining global peatlands for a range of uses. This includes planting trees and crops, harvesting peat to burn for heat, and for other land developments.
For example, some peatlands rely on groundwater, such as portions of the Greater Everglades, the largest freshwater marsh in the United States. Over-pumping groundwater for drinking or irrigation has cut off the peatlands’ source of water.
Together with the regional drier climate due to global warming, our peatlands are drying out worldwide.
What happens when peatlands dry out?
When peat isn’t covered by water, it could be exposed to enough oxygen to fuel aerobic microbes living within. The oxygen allows the microbes to grow extremely fast, enjoy the feast of carbon-rich food, and release carbon dioxide into the atmosphere.
Some peatlands are also a natural source of methane, a potent greenhouse gas with the warming potential up to 100 times stronger than carbon dioxide.
But generating methane actually requires the opposite conditions to generating carbon dioxide. Methane is more frequently released in water-saturated conditions, while carbon dioxide emissions are mostly in unsaturated conditions.
This means if our peatlands are getting drier, we would have an increase in emissions of carbon dioxide, but a reduction in methane emissions.
So what’s the net impact on our climate?
We were part of an international team of scientists across Australia, France, Germany, Netherlands, Switzerland, the US and China. Together, we collected and analysed a large dataset from carefully designed and controlled experiments across 130 peatlands all over the world.
In these experiments, we reduced water under different climate, soil and environmental conditions and, using machine learning algorithms, disentangled the different responses of greenhouse gases.
Our results were striking. Across the peatlands we studied, we found reduced water greatly enhanced the loss of peat as carbon dioxide, with only a mild reduction of methane emissions.
The net effect — carbon dioxide vs methane — would make our climate warmer. This will seriously hamper global efforts to keep temperature rise under 1.5℃.
This suggests if sustainable developments to restore these ecosystems aren’t implemented in future, drying peatlands would add the equivalent of 860 million tonnes of carbon dioxide to the atmosphere every year by 2100. This projection is for a “high emissions scenario”, which assumes global greenhouse gas emissions aren’t cut any further.
Protecting our peatlands
It’s not too late to stop this from happening. In fact, many countries are already establishing peatland restoration projects.
For example, the Central Kalimantan Peatlands Project in Indonesia aims to rehabilitate these ecosystems by, for instance, damming drainage canals, revegetating areas with native trees, and improving local socio-economic conditions and introducing more sustainable agricultural techniques.
Likewise, the Life Peat Restore project aims to restore 5,300 hectares of peatlands back to their natural function as carbon sinks across Poland, Germany and the Baltic states, over five years.
But protecting peatlands is a global issue. To effectively take care of our peatlands and our climate, we must work together urgently and efficiently.
Sven Teske, University of Technology Sydney and Sarah Niklas, University of Technology SydneyThe International Energy Agency (IEA) last month made global headlines when it declared there is no room for new fossil fuel investment if we’re to avoid catastrophic climate change.
However, our new research suggests the horse may have already bolted. We found even if no new fossil fuel projects were approved anywhere in the world, carbon emissions set to be released from existing projects will still push global warming over the dangerous 1.5℃ threshold.
Specifically, even with no new fossil fuel expansion, global emissions would be 22% too high to stay within 1.5℃ by 2025, and 66% too high by 2030.
However, keeping global warming under 1.5℃ is still achievable with rapid deployment of renewables. Our research found solar and wind can supply the world’s energy demand more than 50 times over.
The stunning potential of wind and solar
While our findings were alarming, they also give us a new reason to be hopeful.
We analysed publicly available oil, gas and coal extraction data, and calculated the future production volume. We worked under the assumption no new fossil fuel extraction projects would be developed, and all existing projects would see production declining at standard industry rates.
We found fossil fuel projects already in the pipeline will, by 2030, produce 35% more oil and 69% more coal than what’s consistent with a pathway towards a 1.5℃ temperature rise.
Fossil fuels are the main driver of climate change, accounting for more than 75% of carbon dioxide emissions. Continuing to expand this sector will not only be catastrophic for the climate, but also for the world’s economy as it locks in infrastructure that will become stranded assets.
Ultimately, it’s not enough to simply keep fossil fuels in the ground. To meet our climate goals under the Paris Agreement, we must phase down existing production.
Solar and wind power technologies are already market ready and cost competitive. And as our analysis confirms, they’re ready to be scaled up to meet the energy demands of every person on the planet.
We mapped all the potential areas where wind and solar infrastructure can be built, and the energy potential across six continents.
Even after applying a set of robust, conservative estimates that take environmental safeguards, land constraints and technical feasibility into account, we found that solar and wind energy could meet the world’s energy demand from 2019 — 50 times over.
It’s clear we don’t need new fossil fuel development to ensure 100% energy access in the future.
Australia’s laggard status
In Australia, the Morrison government refuses to set new emissions reduction targets, and continues to fund new fossil fuel projects, such as a A$600 million gas plant in the New South Wales Hunter Valley.
Despite Australia’s laggard status on climate change, there are positive moves elsewhere around the world.
The progress was evident ahead of the G7 summit this past weekend, where climate change was firmly on the agenda. Ahead of the summit, environment ministers worldwide agreed to phase out overseas fossil fuel finance and end support for coal power.
And in recent weeks, three global fossil fuel giants – Shell, Chevron and ExxonMobil – faced legal and shareholder rebukes over their inadequate action on climate change.
Coming on top of all that, the IEA last month set out a comprehensive roadmap to achieve net-zero emissions by 2050. It included a stark warning: no new fossil fuel projects should be approved.
Natural carbon storage is key
However, the IEA’s findings contradict our own on several fronts. We believe the IEA underestimated the very real potential of renewable energy and relied on problematic solutions to fill what it sees as a gap in meeting the carbon budget.
For example, the IEA suggests a sharp increase in bioenergy is required over the next 30 years.
This would require biofuels from energy plantations — planting crops (such as rapeseed) specifically for energy use.
But conservationists estimate the sustainable potential for biofuels is lower. They also say high volumes of bioenergy might interfere with land use for food production and protected nature conservation areas.
Our research found the exact opposite is needed: rapid phase out of deforestation and significant reforestation alongside the decarbonisation of the energy sector.
Bioenergy should be produced predominantly from agricultural and organic waste to remain carbon neutral.
Likewise, the IEA calls for an extreme expansion of carbon capture and storage (CCS) projects — where carbon dioxide emissions are captured at the source, and then pumped and stored deep in the ground.
In its roadmap, the IEA expects CCS projects to grow from capturing 40 million tonnes of carbon dioxide (as is currently the case), to 1,665 million tonnes by 2030.
Establishing natural carbon sinks should be prioritised instead, such as keeping forest, mangrove and seagrass ecosystems better intact to draw carbon dioxide from the atmosphere.
Phasing out early
As a wealthy country, Australia is better placed than most to weather any economic disruption from the energy transition.
Our research shows Australia should phase out fossil fuels early and urgently. The Australian government should also ensure communities and people reliant on fossil fuel industries are helped through the transition.
We must also support poorer countries highly dependent on fossil fuels, particularly in the Asia-Pacific region.
There is new international momentum for climate action, and the future of the fossil fuel industry looks increasingly dire. The technologies to make the transition are ready and waiting – now all that’s needed is political will.
Sven Teske, Research Director, Institute for Sustainable Futures, University of Technology Sydney and Sarah Niklas, Research Consultant, Institute for Sustainable Futures, University of Technology Sydney
Hugh Saddler, Australian National University and Frank Jotzo, Australian National UniversityWorld leaders including Prime Minister Scott Morrison will gather in the UK this weekend for the G7 summit. In a speech on Wednesday ahead of the meeting, Morrison said Australia recognises the need to reach net-zero emissions in order to tackle climate change, and expects to achieve the goal by 2050.
So has Australia started the journey towards deep cuts in greenhouse gas emissions?
In the electricity supply system, the answer is yes, as renewables form an ever-greater share of the electricity mix. But elsewhere in the energy sector – in transport, industry and buildings – there has been little or no progress.
This situation needs to change. These other parts of the energy system contribute nearly 40% of all national greenhouse gas emissions – and the share is growing. In a new working paper out today, we propose a way to track the low-carbon transition across the energy sector and check progress over the last decade.
A stark contrast
The energy sector can be separated into three major types of energy use in Australia:
- electricity generation
- transport and mobile equipment used in mining, farming, and construction
- all other segments, mainly fossil fuel combustion to provide heat in industry and buildings.
In 2018-19, energy sector emissions accounted for 72% of Australia’s national total. Transition from fossil fuels to zero-emissions sources is at the heart of any strategy to cut emissions deeply.
The transition is already happening in electricity generation, as wind and solar supplies increase and coal-fired power stations close or operate less.
But in stark contrast, elsewhere in the sector there is no evidence of a meaningful low-emissions transition or acceleration in energy efficiency improvement.
This matters greatly because in 2019, these other segments contributed 53% of total energy combustion emissions and 38% of national greenhouse gas emissions. Total energy sector emissions increased between 2005 (the reference year for Australia’s Paris target) and 2019.
As the below graphic shows, while the renewables transition often gets the credit for Australia’s emissions reductions, falls since 2005 are largely down to changes in land use and forestry.
Let’s take a closer look at the areas where Australia could do far better in future.
1. Transport and mobile equipment
Transport includes road and rail transport, domestic aviation and coastal shipping. Mobile equipment includes machinery such as excavators and dump trucks used in mining, as well as tractors, bulldozers and other equipment used in farming and construction. Petroleum supplies almost 99% of the energy consumed by these machines.
Road transport is responsible for more than two-thirds of all the energy consumed by transport and mobile equipment.
What’s more, prior to COVID, energy use by transport and mobile equipment was steadily growing – as were emissions. The absence of fuel efficiency standards in Australia, and a trend towards larger cars, has contributed to the problem.
Electric vehicles offer great hope for cutting emissions from the transport sector. As Australia’s electricity grid continues to decarbonise, emissions associated with electric vehicles charged from the grid will keep falling.
2. Other energy emissions
Emissions from all other parts of the energy system arise mainly from burning:
- gas to provide heat for buildings and manufacturing, and for the power needed to liquefy gas to make LNG
- coal, for a limited range of heavy manufacturing activities, such as steel and cement production
- petroleum products (mainly LPG) in much smaller quantities, where natural gas is unavailable or otherwise unsuitable.
Emissions from these sources, as a share of national emissions, rose from 13% in 2005 to 19% in 2019.
These types of emissions can be reduced through electrification – that is, using low- or zero-carbon electricity in industry and buildings. This might include using induction cooktops, and electric heat pumps to heat buildings and water.
However the data offer no evidence of such a shift. Fossil fuel use in this segment has declined, but mainly due to less manufacturing activity rather than cleaner energy supply.
And in 2018 and 2019, the expanding LNG industry drove further emissions growth, offsetting the decline in use of gas and coal in manufacturing.
How to track progress
Over the past decade or so, Australia’s emissions reduction policies – such as they are – have focused on an increasingly narrow range of emission sources and reduction opportunities, in particular electricity generation.
Only now are electric vehicles beginning to be taken seriously, while energy efficiency – a huge opportunity to cut emissions and costs – is typically ignored.
Our paper proposes a large set of new indicators, designed to show what’s happening (and not happening) across the energy sector.
The indicators fall into four groups:
- greenhouse gas emissions from energy use
- primary fuel mix including for electricity generation
- final energy consumption including energy use efficiency
- the fuel/technology mix used to deliver energy services to consumers.
Our datasets excludes the effects of 2020 COVID-19 lockdowns. They’re based on data contained in established government publications: The Australian Energy Statistics, the National Greenhouse Gas Inventory and the Australian Bureau of Statistics’ national accounts and population estimates.
By systematically tracking and analysing these indicators, and combining them with others, Australia’s energy transition can be monitored on an ongoing basis. This would complement the great level of detail already available for electricity generation. It would also create better public understanding and focus policy attention on areas that need it.
In some countries, government agencies monitor the energy transition in great detail. In some cases, such as Germany, independent experts also conduct systematic and substantial analysis as part of an annual process.
The road ahead
Australia has begun the journey to a zero-emissions energy sector. But we must get a move-on in transport, industry and buildings.
The technical opportunities are there. What’s now needed is government regulation and policy to encourage investment in zero-emissions technologies for both supplying and using all forms of energy.
And once available, the technology should be deployed now and in coming years, not in the distant future.
Hugh Saddler, Honorary Associate Professor, Centre for Climate Economics and Policy, Australian National University and Frank Jotzo, Director, Centre for Climate and Energy Policy, Australian National University
Nerilie Abram, Australian National University; Martin De Kauwe, UNSW, and Sarah Perkins-Kirkpatrick, UNSWSenator Matt Canavan sent many eyeballs rolling yesterday when he tweeted photos of snowy scenes in regional New South Wales with a sardonic two-word caption: “climate change”.
Prime Minister Scott Morrison has previously insisted there is “no dispute in this country about the issue of climate change, globally, and its effect on global weather patterns”. But Canavan’s tweet would suggest otherwise.
The reality is, as the climate warms, record-breaking cold weather is becoming less common. And one winter storm does not negate more than a century of human-caused global warming. Here, we take a closer look at the cold weather misconception and two other common climate change myths.
Myth #1: A cold snap means global warming isn’t happening
Canavan’s tweet is an example of a common tactic used by climate change deniers that deliberately conflates weather and climate.
Parts of Australia are currently in the grip of a cold snap as icy air from Antarctica is funnelled up over the eastern states. This is part of a normal weather system, and is temporary.
Climate, on the other hand, refers to weather conditions over a much longer period, such as several decades. And as our climate warms, the probability of such weather systems bringing record-breaking cold temperatures reduces dramatically.
Just as average temperatures in Australia have risen markedly over the past century, so too have winter temperatures. That doesn’t mean climate change is not happening. In a warming world, extremely cold winter temperatures can still occur, but less often than they used to.
In fact, human-caused climate change means extreme winter warmth now occurs more often, and across larger parts of the country. Record-breaking hot events in Australia now far outweigh record breaking cold events.
Myth #2: Global warming is good for us
Yes, climate change may bring isolated benefits. For example, warmer global temperatures may mean fewer people die from extreme cold weather, or that shorter shipping routes open up across the Arctic as sea ice melts.
But the perverse benefits that may flow from climate change will be far outweighed by the damage caused.
Extreme heat can be fatal for humans. And a global study found 37% of heat-related deaths are a direct consequence of human-caused climate change. That means nearly 3,000 deaths in Brisbane, Sydney and Melbourne between 1991 and 2018 were due to climate change.
Extreme heat and humidity may make some parts of the world, especially those near the Equator, essentially uninhabitable by the end of this century.
Global warming also kills plants, animals and ecosystems. In 2018, an estimated one-third of Australia’s spectacled flying foxes died when temperatures around Cairns reached 42℃. And there is evidence many Australian plants will not cope well in a warmer world – and are already nearing their tipping point.
Heatwaves also damage oceans. The Great Barrier Reef has suffered three mass bleaching events in just five years. Within decades the natural wonder is unlikely to exist in is current form – badly hurting employment and tourism.
Myth #3: More CO₂ means Earth will definitely get greener
In January last year, News Corp columnist Andrew Bolt caused a stir with an article that suggested rising carbon dioxide (CO₂) emissions were “greening the planet” and were therefore “a good thing”.
During photosynthesis, plants absorb CO₂. So as the concentration of CO₂ in the atmosphere increases, some researchers predict the planet will become greener and crop yields will increase.
Consistent with this hypothesis, there is indirect evidence of increased global photosynthesis and satellite-observed greening. There is also indirect evidence of increased “carbon sinks”, whereby CO₂ is drawn down from the atmosphere by plants, then stored in soil.
Rising temperatures lead to an earlier onset of spring, as well as prolonged summer plant growth – particularly in the Northern Hemisphere. Researchers think this has triggered an increase in the land carbon sink.
However, there’s also widespread evidence some trees are not growing as might be expected given the increased CO₂ levels in our atmosphere. For example, a study of how Australian eucalypts might respond to future CO₂ concentrations has so far found no increase in growth.
Increased plant growth may also cause them to use more water, causing significant reductions in streamflow that will compound water availability issues in dry regions.
Overall, attempts to reconcile the various lines of evidence of how climate change will alter Earth’s land vegetation have proved challenging.
So, are we doomed?
After all this bad news, you might be feeling a bit dejected. And true, the current outlook isn’t great.
Earth has already warmed by about 1℃, and current policies have the world on track for at least 3℃ warming this century. But there is still reason for hope. While every extra bit of warming matters, so too does every action to reduce greenhouse gas emissions.
And there are promising signs of increasing ambition to reduce greenhouse gas emissions on the global front – from the United States, the United Kingdom, the European Union, Japan and others.
Unfortunately, Australia is far behind our international peers, instead pushing the burden of action onto future generations. We now need the political leadership to set our country, and the world, on a safer and more secure path. Ill-informed tweets by senior members of the government only set back the cause.
Nerilie Abram, Professor; ARC Future Fellow; Chief Investigator for the ARC Centre of Excellence for Climate Extremes; Deputy Director for the Australian Centre for Excellence in Antarctic Science, Australian National University; Martin De Kauwe, Senior lecturer, UNSW, and Sarah Perkins-Kirkpatrick, ARC Future Fellow, UNSW