Scott Morrison has taken another, albeit very small, step towards endorsing a target of net zero emissions by 2050.
He told the National Press Club on Monday: “Our goal is to reach net zero emissions as soon as possible, and preferably by 2050”.
This follows his previous wording of wanting net zero “as quickly as possible”.
It remains unclear whether the baby steps will lead to his embracing the 2050 target later this year. But he’d almost certainly like to do so – it would undoubtedly smooth the way with the Biden administration as well as putting Australia in a better position for the Glasgow climate conference in November.
But there are pesky Nationals (and a few others) ready to make the road rocky.
The next climate test for Morrison is President Biden’s planned leaders’ climate summit on Earth Day, April 22.
Climate is at the centre of the Biden agenda, which makes the April summit particularly important.
The President’s climate envoy John Kerry told a White House press briefing last week: “the convening of … this summit is essential to ensuring that 2021 is going to be the year that really makes up for the lost time of the last four years and that the U.N. Climate Conference — COP26, as it’s called, which the UK is hosting in November — to make sure that it is an unqualified success”.
Kerry spoke to energy minister Angus Taylor last week when, according to the Australia readout of the discussion, Kerry “welcomed Australia’s commitment to achieving net zero emissions as soon as possible”.
As, perhaps, one might welcome an infant’s early progress.
Asked on Monday whether he expected to attend the Biden climate conference, Morrison replied cautiously, on the basis of lack of information.
Perhaps he didn’t want to take any risks. In December he was embarrassed when an expected invitation to a speaking spot at the “climate ambition summit” hosted by Britain, France and the United Nations didn’t eventuate. Australia was judged as not having sufficient “ambition” to warrant a slot.
“ At this stage, we haven’t received the details or nature of the event,” Morrison said of the April gathering.
“As you can appreciate, things are very busy over in the White House at the moment.”
When details were received, “then I’m sure the Minister for Foreign Affairs, Marise Payne and I, and Angus Taylor, and others, will discuss what is the best way for us to participate in that and how that will work.
“But we welcome it and we look forward to supporting it.”
Maybe there’ll be more to know when Morrison speaks to Biden. As of Monday, the PM was still waiting fot his first post-inauguration call from the President (they spoke after the election). The Prime Minister’s Office could only say the call was expected “within coming days”.
Morrison on Monday repeated strongly his mantra of advancing climate policy by “technology” not “tax”.
If he does move to the 2050 target, the rationale he will give for the shift will be the progress of technology.
“My commitment to Australians that I will not tax our way to net zero by 2050 is a very, very important one and I will hold my faith with the Australian people on those issues. So we will see how the technology develops,” he said.
If he wished, he obviously could use “technology” at any point as his cover for changing his position. The issue will be if and when he thinks he has the political cover.
Global emissions are expected to decline by about 7% in 2020 (or 2.4 billion tonnes of carbon dioxide) compared to 2019 — an unprecedented drop due to the slowdown in economic activity associated with the COVID-19 pandemic.
To put this into perspective, the Global Financial Crisis in 2008 saw a 1.5% drop in global emissions compared to 2007. This year’s emissions decline is more than four times larger.
It may sound like welcome news, but we can’t celebrate yet. A rapid bounce back of emissions to pre-COVID levels is likely, possibly by as soon as next year. A recent study found emissions in China snapped back to above last year’s levels during late spring when economic activity began to return to normal.
These findings come ahead of the Climate Ambition Summit on Saturday, where global leaders will demonstrate their commitments to climate action five years since the Paris Agreement. This huge drop in emissions should be taken as a unique opportunity to divert the historical course of emissions growth for good.
Emissions in the pandemic year
The total global fossil carbon dioxide emissions for 2020 are estimated to be 34 billion tonnes of carbon dioxide.
Estimated emissions at the beginning of December are lower than their levels in December last year, at least in the transport sectors. However, emissions have been edging back up since the peak global daily decline of 17% in early April.
The decline in emissions in 2020 was particularly steep in the United States (12%) and European Union (11%), where emissions were already declining before the pandemic, mainly from reductions in coal use.
Emissions from India dropped by 9%, while emissions from China, which have returned to close or above 2019 values, saw an estimated drop of only about 1.7%.
Australian greenhouse gas emissions during the peak of the pandemic lockdown (the quarter of March to June 2020) were lower by 6.2% compared to the previous quarter. The largest declines were seen in transport and fugitive emissions (emissions released during the extraction, processing and transport of fossil fuels).
Globally, the transport sector also contributed the most to the 2020 emissions drop, particularly “surface transport” (cars, vans and trucks). At the peak of the pandemic lockdowns, the usual levels of transport emissions were halved in many countries, such as in the US and Europe.
While aviation activity collapsed by 75%, its contribution to the total decline was relatively small given the sector only accounts for about 2.8% of the total emissions on an average year. The number of global flights was still down 45% as of the first week of December.
Global emissions were already slowing down pre-COVID
Overall, global emissions have increased by 61% since 1990. But the pace of this growth has varied.
In the early 1990s, the growth in emissions slowed down due to the collapse of the former Soviet Union, but then increased very quickly during the 2000s, by 3% per year on average. This was, in part, due to the rise of China as an economic power.
Over the last decade, however, the pace of emissions began to slow again, with an increase just below 1% per year. And emissions in 2019 didn’t grow much, if at all, when compared to 2018.
Behind the global slowing trend, there are 24 countries that had carbon dioxide fossil emissions declining for at least one decade while their economy continued to grow. They include many European countries such as the Denmark, the UK and Spain, and the USA, Mexico and Japan. For the rest of the world, emissions continued to grow until 2019.
An opportunity to boost ambition
The pandemic, along with other recent trends such as the shift towards clean energy, have placed us at a crossroad: the choices we make today can change the course of global emissions.
In addition to the slow down in global emissions in recent years, and this year’s drop, there are now dozens of countries that have pledged to reach net zero emissions by mid century or soon after.
Importantly, the first (China), second (USA), third (European Union), sixth (Japan) and ninth (South Korea) top emitters — together responsible for over 60% of the global fossil carbon dioxide emissions — have either legally binding pledges or serious ambitions to reach net zero emissions by 2050 or soon after.
Coal production, the largest fossil fuel source of carbon dioxide emissions, peaked in 2013. Its decline continues to this date; however, increasing natural gas and oil negate much of this decline in emissions.
We are in the midst of extraordinary levels of economic investment in response to the pandemic. If economic investment is appropriately directed, it could enable the rapid expansion of technologies and services to put us on track towards net zero emissions.
Many countries have already committed to green recovery plans, such as South Korea and the EU, although investments continue to be dominated by the support of fossil-based infrastructure.
As global leaders prepare for tomorrow’s summit, they have an opportunity like never before. The choices we make now can have a disproportionate impact on the future trajectory of emissions, and keep temperature rise well and truly below 2℃.
Australia is on track to meet its 2030 Paris climate targets without resorting to carryover credits and could exceed them with the aid of the recently-announced technology roadmap, according to projections to be released on Thursday.
Australia has pledged to reduce emissions by 26-28% on 2005 levels by 2030.
The annual update of emissions projections shows that to meet the 26% cut, without using carryover credits, a further reduction of 56 million tonnes would be needed over the decade to 2030.
To reach the higher target of a 28% cut without the credits, a reduction of 123 million tonnes would be required over the decade.
Neither of these scenarios includes the technology investment roadmap – which is the government’s policy to support new and emerging energy technologies to a price that is comparable with higher emitting alternatives.
The Minister for Emissions Reduction, Angus Taylor, said if the roadmap was taken into account, “Australia is projected to beat its 2030 target by 145 million tonnes”.
This would be without relying on the credits which have been gained from exceeding earlier targets.
“Under this scenario, Australia’s emissions are projected to be 29% below 2005 levels by 2030,” Taylor said.
Scott Morrison has flagged the government won’t use the carryovers if they are not necessary to meet Australia’s commitments.
He is set to confirm this when he addresses a Pacific Islands Forum virtual climate summit on Friday. This precedes the Climate Ambition Summit hosted by Britain, France and the United Nations at the weekend to mark the fifth anniversary of the Paris accord.
The Pacific summit is aimed at putting pressure on the weekend meeting, which is being called “the sprint to Glasgow”, the delayed climate conference to be held in a year’s time.
There has been argy bargy over whether Morrison could get a speaking role at the weekend meeting, where leaders are being asked to make new commitments. As of Wednesday, he was not expected to be a speaker.
The update in the Australia’s emissions projections 2020 report shows Australia’s position against the 2030 target has improved by more than 300 million tonnes since the 2019 projections, and by 639 million tonnes since 2018.
The improvement since 2018 is equivalent to taking all of the country’s passenger vehicles off the road for 15 years.
Emissions are projected to decline to 478 million tonnes in 2030 which is 22% below 2005 levels. Incorporating the technology investment roadmap, emissions are forecast to be 436 million tonnes in 2030 – 29% below 2005 levels.
The update says the downward revision in the 2020 projections reflects:
the inclusion of new measures to speed up the development and deployment of low emissions technologies in the recent budget
a further reduction in projected emissions from the electricity sector due to continued strong uptake of renewables – especially small and mid-scale solar – by households and businesses; and
the temporary effect of COVID-related restrictions on the economy.
This colossal amount of nitrogen makes crops and pastures grow more abundantly. But it also releases nitrous oxide (N₂O), a greenhouse gas.
Agriculture is the main cause of the increasing concentrations, and is likely to remain so this century. N₂O emissions from agriculture and industry can be reduced, and we must take urgent action if we hope to stabilise Earth’s climate.
Where does nitrous oxide come from?
We found that N₂O emissions from natural sources, such as soils and oceans, have not changed much in recent decades. But emissions from human sources have increased rapidly.
Atmospheric concentrations of N₂O reached 331 parts per billion in 2018, 22% above levels around the year 1750, before the industrial era began.
Agriculture caused almost 70% of global N₂O emissions in the decade to 2016. The emissions are created through microbial processes in soils. The use of nitrogen in synthetic fertilisers and manure is a key driver of this process.
Other human sources of N₂O include the chemical industry, waste water and the burning of fossil fuels.
N₂O is destroyed in the upper atmosphere, primarily by solar radiation. But humans are emitting N₂O faster than it’s being destroyed, so it’s accumulating in the atmosphere.
N₂O both depletes the ozone layer and contributes to global warming.
As a greenhouse gas, N₂O has 300 times the warming potential of carbon dioxide (CO₂) and stays in the atmosphere for an average 116 years. It’s the third most important greenhouse gas after CO₂ (which lasts up to thousands of years in the atmosphere) and methane.
N₂O depletes the ozone layer when it interacts with ozone gas in the stratosphere. Other ozone-depleting substances, such as chemicals containing chlorine and bromine, have been banned under the United Nations Montreal Protocol. N₂O is not banned under the protocol, although the Paris Agreement seeks to reduce its concentrations.
What we found
The Intergovernmental Panel on Climate Change has developed scenarios for the future, outlining the different pathways the world could take on emission reduction by 2100. Our research found N₂O concentrations have begun to exceed the levels predicted across all scenarios.
The current concentrations are in line with a global average temperature increase of well above 3℃ this century.
We found that global human-caused N₂O emissions have grown by 30% over the past three decades. Emissions from agriculture mostly came from synthetic nitrogen fertiliser used in East Asia, Europe, South Asia and North America. Emissions from Africa and South America are dominated by emissions from livestock manure.
In terms of emissions growth, the highest contributions come from emerging economies – particularly Brazil, China, and India – where crop production and livestock numbers have increased rapidly in recent decades.
N₂O emissions from Australia have been stable over the past decade. Increase in emissions from agriculture and waste have been offset by a decline in emissions from industry and fossil fuels.
What to do?
N₂O must be part of efforts to reduce greenhouse gas emissions, and there is already work being done. Since the late 1990s, for example, efforts to reduce emissions from the chemicals industry have been successful, particularly in the production of nylon, in the United States, Europe and Japan.
Reducing emissions from agriculture is more difficult – food production must be maintained and there is no simple alternative to nitrogen fertilisers. But some options do exist.
In Europe over the past two decades, N₂O emissions have fallen as agricultural productivity increased. This was largely achieved through government policies to reduce pollution in waterways and drinking water, which encouraged more efficient fertiliser use.
Other ways to reduce N₂O emissions from agriculture include:
better management of animal manure
applying fertiliser in a way that better matches the needs of growing plants
alternating crops to include those that produce their own nitrogen, such as legumes, to reduce the need for fertiliser
enhanced efficiency fertilisers that lower N₂O production.
Getting to net-zero emissions
Stopping the overuse of nitrogen fertilisers is not just good for the climate. It can also reduce water pollution and increase farm profitability.
Even with the right agricultural policies and actions, synthetic and manure fertilisers will be needed. To bring the sector to net-zero greenhouse gas emissions, as needed to stabilise the climate, new technologies will be required.
Astronomers know all too well how precious and unique the environment of our planet is. Yet the size of our carbon footprint might surprise you.
Our study, released today in Nature Astronomy, estimated the field produces 25,000 tonnes of carbon dioxide-equivalent emissions per year in Australia. With fewer than 700 active researchers nationwide (including PhD students), this translates to 37 tonnes per astronomer per year.
As a point of reference, the average Australian adult was responsible for 26 tonnes of emissions in 2019, total. That means the job of being an astronomer is 40% more carbon-intensive than the average Australian’s job and home life combined.
While we often defer to governments for climate policy, our global carbon footprint can be dramatically reduced if every industry promotes strategies to reduce their own footprint. For individual industries to make progress, they must first recognise just how much they contribute to the climate emergency.
Where do all the emissions come from?
We found 60% of astronomy’s carbon footprint comes from supercomputing. Astronomers rely on supercomputers to not only process the many terabytes of data they collect from observatories everyday, but also test their theories of how the Universe formed with simulations.
Frequent flying has historically been par for the course for astronomers too, be it for conference attendance or on-site observatory visits all around the world. Prior to COVID-19, six tonnes of annual emissions from flights were attributed to the average astronomer.
An estimated five tonnes of additional emissions per astronomer are produced in powering observatories every year. Astronomical facilities tend to be remote, to escape the bright lights and radio signals from populous areas.
Others, like the Murchison Radio-astronomy Observatory in Western Australia, need to be powered by generators on site. Solar panels currently provide around 15% of the energy needs at the Murchison Radio-astronomy Observatory, but diesel is still used for the bulk of the energy demands.
Finally, the powering of office spaces accounts for three tonnes of emissions per person per year. This contribution is relatively small, but still non-negligible.
They’re doing it better in Germany
Australia has an embarrassing record of per-capita emissions. At almost four times the global average, Australia ranks in the top three OECD countries for the highest per-capita emissions. The problem at large is Australia’s archaic reliance on fossil fuels.
The difference lies in the amount of renewable energy available in Germany versus Australia. The carbon emissions produced for each kilowatt-hour of electricity consumed at the German institute is less than a third pulled from the grid in Australia, on average.
The challenge astronomers in Australia face in reducing their carbon footprint is the same challenge all Australian residents face. For the country to claim any semblance of environmental sustainability, a swift and decisive transition to renewable energy is needed.
Taking emissions reduction into our own hands
A lack of coordinated action at a national level means organisations, individuals, and professions need to take emissions reduction into their own hands.
For astronomers, private arrangements for supercomputing centres, observatories, and universities to purchase dedicated wind and/or solar energy must be a top priority. Astronomers do not control the organisations that make these decisions, but we are not powerless to effect influence.
CSIRO expects the increasing fraction of on-site renewables at the Murchison Radio-astronomy Observatory has the potential to save 2,000 tonnes of emissions per year from diesel combustion. And most major universities in Australia have released plans to become carbon-neutral this decade.
As COVID-19 halted travel worldwide, meetings have transitioned to virtual platforms. Virtual conferences have a relatively minute carbon footprint, are cheaper, and have the potential to be more inclusive for those who lack the means to travel. Despite its challenges, COVID-19 has taught us we can dramatically reduce our flying. We must commit this lesson to memory.
Methane is a shorter-lived greenhouse gas – why do we average it out over 100 years? By doing so, do we risk emitting so much in the upcoming decades that we reach climate tipping points?
The climate conversation is often dominated by talk of carbon dioxide, and rightly so. Carbon dioxide is the climate warming agent with the biggest overall impact on the heating of the planet.
But it is not the only greenhouse gas driving climate change.
Comparing apples and oranges
For the benefit of policy makers, the climate science community set up several ways to compare gases to aid with implementing, monitoring and verifying emissions reduction policies.
In almost all cases, these rely on a calculated common currency – a carbon dioxide-equivalent (CO₂-e). The most common way to determine this is by assessing the global warming potential (GWP) of the gas over time.
The simple intent of GWP calculations is to compare the climate heating effect of each greenhouse gas to that created by an equivalent amount (by mass) of carbon dioxide.
In this way, emissions of one gas – like methane – can be compared with emissions of any other – like carbon dioxide, nitrous dioxide or any of the myriad other greenhouse gases.
These comparisons are imperfect but the point of GWP is to provide a defensible way to compare apples and oranges.
Limits of metrics
Unlike carbon dioxide, which is relatively stable and by definition has a GWP value of one, methane is a live-fast, die-young greenhouse gas.
Methane traps very large quantities of heat in the first decade after it is released in to the atmosphere, but quickly breaks down.
After a decade, most emitted methane has reacted with ozone to form carbon dioxide and water. This carbon dioxide continues to heat the climate for hundreds or even thousands of years.
Emitting methane will always be worse than emitting the same quantity of carbon dioxide, no matter the time scale.
How much worse depends on the time period used to average out its effects. The most commonly used averaging period is 100 years, but this is not the only choice, and it is not wrong to choose another.
As a starting point, the Intergovernmental Panel on Climate Change’s (IPCC) Fifth Assessment Report from 2013 says methane heats the climate by 28 times more than carbon dioxide when averaged over 100 years and 84 times more when averaged over 20 years.
Many sources of methane
On top of these base rates of warming, there are other important considerations.
Fully considered using the 100-year GWP and including natural feedbacks, the IPCC’s report says fossil sources of methane – most of the gas burned for electricity or heat for industry and houses – can be up to 36 times worse than carbon dioxide. Methane from other sources – such as livestock and waste – can be up to 34 times worse.
These works will be assessed in the IPCC’s upcoming Sixth Assessment Report, with the physical science contribution due in 2021.
While we should prefer the most up to date science at any given time, the choice to consider – or not – the full impact of methane and the choice to consider its impact over 20, 100 or 500 years is ultimately political, not scientific.
Undervaluing or misrepresenting the impact of methane presents a clear risk for policy makers. It is vital they pay attention to the advice of scientists and bodies such as the IPCC.
Undervaluing methane’s impact in this way is not a risk for climate modellers because they rely on more direct assessments of the impact of gases than GWP.
The idea of climate tipping points is that, at some point, we may change the climate so much that it crosses an irreversible threshold.
At such a tipping point, the world would continue to heat well beyond our capability to limit the harm.
There are many tipping points we should be aware of. But exactly where these are – and precisely what the implications of crossing one would be – is uncertain.
Unfortunately, the only way we can be sure of where these tipping points are is to cross them. The only thing we know for sure about them is that the impact on lives, livelihoods and the places we love would be beyond catastrophic if we did.
But we cannot ignore disturbing impacts of climate change that are already here.
The scientific understanding of climate change goes well beyond simple metrics like GWP. Shuffling between metrics – such as 20-year or 100-year GWP – cannot avoid the fact our very best chance of avoiding ever-worsening climate harm is to massively reduce our reliance on coal, oil and gas, along with reducing our emissions from all other sources of greenhouse gas.
If we do this, we offer ourselves the best chance of avoiding crossing thresholds we can never return from.
Its observations in the wake of our Black Summer suggest the commission’s final report, due on October 28, may recommend a major shake-up of how disaster management is governed at the federal level. This includes setting up a national body focused on recovery from and resilience to future disasters.
Most initial observations are uncontroversial and sensible, but there is a glaring omission. It involves the most urgent measure to reduce the risk of future disasters: reducing greenhouse gas emissions.
In my former role as the United Nations Secretary General’s Special Representative for Disaster Risk Reduction, I saw first-hand the impacts of natural disasters, and nations’ efforts to build their climate change resilience. The royal commission process is a unique opportunity to accelerate progress in these areas, which are so critical for Australia’s future.
What’s in the report?
In February, the royal commission was tasked with finding ways to improve disaster management in three main areas:
how the federal government coordinates with other levels of government
resilience to climate change and mitigating disaster risk
the laws governing the federal government response to national emergencies.
The initial observations touch on each of these areas. This includes the need to collate, harmonise and share disaster data across jurisdictions; enhance research in climate and disaster resilience; reassess aerial firefighting capabilities; and plan more effectively around critical infrastructure.
It’s also worth noting the royal commission hasn’t yet formed a view on a key change Prime Minister Scott Morrison suggested was necessary in the wake of the bushfires: establishing the legal authority for the federal government to declare a national state of emergency. Currently, only state and territory governments have this power.
AFAC is a non-government organisation that facilitates the deployment of emergency personnel and equipment interstate and internationally. But the states and territories may not be willing to relinquish the engagement they have under the current arrangements.
Most importantly, the royal commission is considering consolidating disaster recovery and resilience functions in a new national body.
These functions reside in at least three agencies. They include Emergency Management Australia, the National Bushfire Recovery Agency, and the National Drought and North Queensland Flood Response and Recovery Agency.
Consolidation makes good sense as the recovery phase from disasters can contribute to strengthening resilience.
It’s also sensible to separate the resilience function from the disaster response function, currently led by Emergency Management Australia. In my experience, resilience work rarely gets the whole-of-government attention it deserves when it’s embedded in agencies focused around responding to emergencies.
Three months of disasters
After the devastation Black Summer wrought, it’s clear resilience to future disasters must start with action on climate change. So it’s disappointing the royal commission has not yet commented on the need to lower greenhouse gas emissions as rapidly as possible.
Although COVID-19 has masked our awareness of the rapidly increasing climate threat, the evidence — even over just the past three months — is overwhelming.
In June, the record was set for the highest temperature ever recorded in the Arctic. The associated unprecedented heatwave in Siberia contributed to massive bushfires razing an astonishing 20 million hectares.
While Siberia burned, severe floods devastated South Asia, China and Japan. One-third of Bangladesh was underwater, affecting almost 15 million people.
In China the figure was 63 million, with daily rainfall records set across the country. China’s Three Gorges Hydroelectric Dam, the world’s biggest, received the largest inflow of water in its history, prompting fears last week the dam would be breached.
In southern Japan, record-setting rains that dumped 1,000 millimetres of water in just three days forced hundreds of thousands of people from their homes.
Then, earlier this month, deadly fires erupted across California, exacerbated by persistent drought and record-setting temperatures. In just five days, the fires burned more land in the state than was destroyed in all of 2019.
We can’t ignore climate change
While it’s difficult to scientifically demonstrate that climate change “causes” any one disaster, the general direction is crystal clear. As the climate continues to warm, the frequency and severity of these events will increase.
We’re already seeing worrying signs of this in Queensland, our most hazard-prone state. Over the past three years, 53 of Queensland’s 77 local government areas have endured three or more major disasters. And 71 out of 77 local government areas have experienced two or more such events.
These communities are increasingly in the unsustainable situation of chronically recovering from disasters.
The prime minister has argued “Australia, on its own, cannot control the world’s climate, as Australia accounts for just 1.3% of global emissions”.
But because we’re disproportionately vulnerable to the threats of climate change, it’s imperative we convince other nations to reduce their greenhouse gas emissions.
Our international advocacy will only be credible if we strengthen our own ambition to mitigate climate change. And as the government prepares to submit its updated targets under the Paris Climate Agreement, a recommendation to reduce emissions from the royal commission would be appropriate and extremely useful.
To slow climate change, humanity has two main options: reduce greenhouse gas emissions directly or find ways to remove them from the atmosphere. On the latter, storing carbon in soil – or carbon farming – is often touted as a promising way to offset emissions from other sources such as energy generation, industry and transport.
The Morrison government’s Technology Investment Roadmap, now open for public comment, identifies soil carbon as a potential way to reduce emissions from agriculture and to offset other emissions.
In particular, it points to so-called “biochar” – plant material transformed into carbon-rich charcoal then applied to soil.
But the government’s plan contains misconceptions about both biochar, and the general effectiveness of soil carbon as an emissions reduction strategy.
What is biochar?
Through photosynthesis, plants turn carbon dioxide (CO₂) into organic material known as biomass. When that biomass decomposes in soil, CO₂ is produced and mostly ends up in the atmosphere.
This is a natural process. But if we can intervene by using technology to keep carbon in the soil rather than in the atmosphere, in theory that will help mitigate climate change. That’s where biochar comes in.
Making biochar involves heating waste organic materials in a reduced-oxygen environment to create a charcoal-like product – a process called “pyrolysis”. The carbon from the biomass is stored in the charcoal, which is very stable and does not decompose for decades.
Plant materials are the predominant material or “feedstock” used to make biochar, but livestock manure can also be used. The biochar is applied to the soil, purportedly to boost soil fertility and productivity. This has been tested on grassland, cropping soils and in vineyards.
But there’s a catch
So far, so good. But there are a few downsides to consider.
First, the pyrolysis process produces combustible gases and uses energy – to the extent that when all energy inputs and outputs are considered in a life cycle analysis, the net energy balance can be negative. In other words, the process can create more greenhouse gas emissions than it saves. The balance depends on many factors including the type and condition of the feedstock and the rate and temperature of pyrolysis.
Second, while biochar may improve the soil carbon status at a new site, the sites from which the carbon residues are removed, such as farmers’ fields or harvested forests, will be depleted of soil carbon and associated nutrients. Hence there may be no overall gain in soil fertility.
Third, the government roadmap claims increasing soil carbon can reduce emissions from livestock farming while increasing productivity. Theoretically, increased soil carbon should lead to better pasture growth. But the most efficient way for farmers to take advantage of the growth, and increase productivity, is to keep more livestock per hectare.
Livestock such as cows and sheep produce methane – a much more potent greenhouse gas than carbon dioxide. Our analysis suggests the methane produced by the extra stock would exceed the offsetting effect of storing more soil carbon. This would lead to a net increase, not decrease, in greenhouse gas
A policy failure
The government plan refers to the potential to build on the success of the Emissions Reduction Fund. Among other measures, the fund pays landholders to increase the amount of carbon stored in soil through carbon credits issued through the Carbon Farming Initiative.
However since 2014, the Emissions Reduction Fund has not significantly reduced Australia’s greenhouse gas emissions – and agriculture’s contribution has been smaller still.
So far, the agriculture sector has been contracted to provide about 9.5% of the overall abatement, or about 18.3 million tonnes. To date, it’s supplied only 1.54 million tonnes – 8.4% of the sector’s commitment.
The initiative has largely failed because several factors have made it uneconomic for farmers to take part. They include:
overly complex regulations
requirements for expensive soil sampling and analysis
the low value of carbon credits (averaging $12 per tonne of CO₂-equivalent since the scheme began).
A misguided strategy
We believe the government is misguided in considering soil carbon as an emissions reduction technology.
Certainly, increasing soil carbon at one location can boost soil fertility and potentially productivity, but these are largely private landholder benefits – paid for by taxpayers in the form of carbon credits.
If emissions reduction is seen as a public benefit, then the payment to farmers becomes a subsidy. But it’s highly questionable whether the public benefit (in the form of reduced emissions) is worth the cost. The government has not yet done this analysis.
To be effective, future emissions technology in Australia should focus on improving energy efficiency in industry, the residential sector and transport, where big gains are to be made.
COVID-19 has curtailed the activities of millions of people across the world and with it, greenhouse gas emissions. As climate scientists at the Cape Grim Baseline Air Pollution Station, we are routinely asked: does this mean carbon dioxide concentrations in the atmosphere have fallen?
The answer, disappointingly, is no. Throughout the pandemic, atmospheric carbon dioxide (CO₂) levels continued to rise.
In fact, our measurements show more CO₂ accumulated in the atmosphere between January and July 2020 than during the same period in 2017 or 2018.
Emissions from last summer’s bushfires may have contributed to this. But there are several other reasons why COVID-19 has not brought CO₂ concentrations down at Cape Grim – let’s take a look at them.
Measuring the cleanest air in the world
Cape Grim is on the northwest tip of Tasmania. Scientists at the station, run by the CSIRO and Bureau of Meteorology, have monitored and studied the global atmosphere for the past 44 years.
The air we monitor is the cleanest in the world when it blows from the southwest, off the Southern Ocean. Measurements taken during these conditions are known as “baseline concentrations”, and represent the underlying level of carbon dioxide in the Southern Hemisphere’s atmosphere.
Emissions reductions due to COVID-19 started in China in January, and peaked globally in April. Our measurements show atmospheric CO₂ levels rose during that period. In January 2020, baseline CO₂ was 408.3 parts per million (ppm) at Cape Grim. By July that had risen to 410 ppm.
Since the station first began measurements in 1976, carbon dioxide levels in the atmosphere have increased by 25%, as shown in the graph below. The slowdown in the rate of carbon emissions during the pandemic is a mere tug against this overall upward trend.
The CO₂ increase is due to the burning of fossil fuels for energy, and land use change such as deforestation which leaves fewer trees to absorb CO₂ from the air, and changes the uptake and release of carbon in the soils.
Large air circulation patterns in the atmosphere spread gases such as CO₂ around the world, but this process takes time.
Most emissions reduction due to COVID-19 occurred in the Northern Hemisphere, because that’s where most of the world’s population lives. Direct measurements of CO₂ in cities where strict lockdown measures were imposed show emissions reductions of up to 75%. This would have reduced atmospheric CO₂ concentrations locally.
But it will take many months for this change to manifest in the Southern Hemisphere atmosphere – and by the time it does, the effect will be significantly diluted.
Natural ups and downs
Emissions reductions during COVID-19 are a tiny component of a very large carbon cycle. This cycle is so dynamic that even when the emissions slowdown is reflected in atmospheric CO₂ levels, the reduction will be well within the cycle’s natural ebb and flow.
Here’s why. Global carbon emissions have grown by about 1% a year over the past decade. This has triggered growth in atmospheric CO₂ levels of between 2 and 3 ppm per year in that time, as shown in the graph below. In fact, since our measurements began, CO₂ has accumulated more rapidly in the atmosphere with every passing decade, as emissions have grown.
But although CO₂ emissions have grown consistently, the resulting rate of accumulation in the atmosphere varies considerably each year. This is because roughly half of human emissions are mopped up by ecosystems and the oceans, and these processes change from year to year.
For example, in southeast Australia, last summer’s extensive and prolonged bushfires emitted unusually large amounts of CO₂, as well as changing the capacity of ecosystems to absorb it. And during strong El Niño events, reduced rainfall in some regions limits the productivity of grasslands and forests, so they take up less CO₂.
The graph below visualises this variability. It shows the baseline CO₂ concentrations for each year, relative to January 1. Note how the baseline level changes through a natural seasonal cycle, how that change varies from year to year and how much CO₂ has been added to the atmosphere by the end of the year.
The growth rate has been as much as 3 ppm per year. The black line represents 2020 and lines for the preceding five years are coloured. All show recent annual growth rates of about 2-3 ppm/year – a variability in the range of about 1 ppm/year.
Research in May estimated that due to the COVID-19 lockdowns, global annual average emissions for 2020 would be between 4.2% and 7.5% lower than for 2019.
Let’s simplistically assume CO₂ concentration growth reduces by the same amount. There would be 0.08-0.23 ppm less CO₂ in the atmosphere by the end of 2020 than if no pandemic occurred. This variation is well within the natural 1 ppm/year annual variability in CO₂ growth.
The road ahead
It’s clear COVID-19 has not solved the climate change problem. But this fact helps us understand the magnitude of change required if we’re to stabilise the global climate system.
The central aim of the Paris climate agreement is to limit global warming to well below 2℃, and pursue efforts to keep it below 1.5℃. To achieve this, global CO₂ emissions must decline by 3% and 7% each year, respectively, until 2030, according to the United Nations Emissions Gap Report.
Thanks to COVID-19, we may achieve this reduction in 2020. But to lock in year-on-year emissions reductions that will be reflected in the atmosphere, we must act now to make deep, significant and permanent changes to global energy and economic systems.
The lead author, Zoe Loh, discusses the CO₂ record from Cape Grim in Fight for Planet A, showing now on the ABC.
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Is humanity doomed? If in 2030 we have not reduced emissions in a way that means we stay under say 2℃ (I’ve frankly given up on 1.5℃), are we doomed then?
Humanity is not doomed, not now or even in a worst-case scenario in 2030. But avoiding doom — either the end or widespread collapse of civilisation — is setting a pretty low bar. We can aim much higher than that without shying away from reality.
It’s right to focus on global warming of 1.5℃ and 2℃ in the first instance. The many manifestations of climate change — including heat waves, droughts, water stress, more intense storms, wildfires, mass extinction and warming oceans — all get progressively worse as the temperature rises.
Climate scientist Michael Mann uses the metaphor of walking into an increasingly dense minefield.
The global average temperature is currently about 1.2℃ higher than what it was at the time of the Industrial Revolution, some 250 years ago. We are already witnessing localised impacts, including the widespread coral bleaching on Australia’s Great Barrier Reef.
First, it’s possible technically and economically. For example, the use of wind and solar power has grown exponentially in the past decade, and their prices have plummeted to the point where they are now among the cheapest sources of electricity. Some areas, including energy storage and industrial processes such as steel and cement manufacture, still need further research and a drop in price (or higher carbon prices).
Second, it’s possible politically. Partly in response to the Paris Agreement, a growing number of countries have adopted stronger targets. Twenty countries and regions (including New Zealand and the European Union) are now targeting net zero emissions by 2050 or earlier.
A recent example of striking progress comes from Ireland – a country with a similar emissions profile to New Zealand. The incoming coalition’s “programme for government” includes emission cuts of 7% per year and a reduction by half by 2030.
The challenges would be exacerbated and we would have new issues to consider. First, under the “shifting baseline” phenomenon — essentially a failure to notice slow change and to value what is already lost — people might discount the damage already done. Continuously worsening conditions might become the new normal.
Second, climate impacts such as mass migration could lead to a rise of nationalism and make international cooperation harder. And third, we could begin to pass unpredictable “tipping points” in the Earth system. For example, warming of more than 2°C could set off widespread melting in Antarctica, which in turn would contribute to sea level rise.