Why there’s more greenhouse gas in the atmosphere than you may have realised



The Cape Grim observatory, home of the ‘world’s cleanest air’… and rising greenhouse gases.
CSIRO, Author provided

Zoe Loh, CSIRO; Blagoj Mitrevski, CSIRO; David Etheridge, CSIRO; Nada Derek, CSIRO; Paul Fraser, CSIRO; Paul Krummel, CSIRO; Paul Steele, CSIRO; Ray Langenfelds, CSIRO, and Sam Cleland, Australian Bureau of Meteorology

This week brought news that atmospheric carbon dioxide (CO₂) levels at the Mauna Loa atmospheric observatory in Hawaii have risen steeply for the seventh year in a row, reaching a May 2019 average of 414.7 parts per million (ppm).

It was the highest monthly average in 61 years of measurements at that observatory, and comes five years after CO₂ concentrations first breached the 400ppm milestone.

But in truth, the amount of greenhouse gas in our atmosphere is higher still. If we factor in the presence of other greenhouse gases besides carbon dioxide, we find that the world has already ticked past yet another milestone: 500ppm of what we call “CO₂-equivalent”, or CO₂-e.




Read more:
Forty years of measuring the world’s cleanest air reveals human fingerprints on the atmosphere


In July 2018, the combination of long-lived greenhouse gases measured in the “cleanest air in the world” at Cape Grim Baseline Atmospheric Pollution Station surpassed 500ppm CO₂-e.

As the atmosphere of the Southern Hemisphere contains less pollution than the north, this means the global average atmospheric concentration of greenhouse gases is now well above this level.

What is CO₂-e?

Although CO₂ is the most abundant greenhouse gas, dozens of other gases – including methane (CH₄), nitrous oxide (N₂O) and the synthetic greenhouse gases – also trap heat. Many of them are more powerful greenhouse gases than CO₂, and some linger for longer in the atmosphere. That means they have a significant influence on how much the planet is warming.

Southern Hemispheric radiative forcing relative to 1750 due to the long-lived greenhouse gases (carbon dioxide, methane, nitrous oxide and synthetic greenhouse gases), expressed as watts per square metre, from measurements in situ at Cape Grim, from the Cape Grim Air Archive, and Antarctic firn air.
CSIRO

Atmospheric scientists use CO₂-e as a convenient way to aggregate the effect of all the long-lived greenhouse gases.

As all the major greenhouse gases (CO₂, CH₄ and N₂O) are rising in concentration, so too is CO₂-e. It has climbed at an average rate of 3.3ppm per year during this decade – faster than at any time in history. And it is showing no sign of slowing.

Cape Grim/Antarctic carbon dioxide equivalent (CO₂-e) calculated from the long-lived greenhouse gas radiative forcing data shown in the figure above with CO₂ data shown for reference, annual data through to 2018. Inset panel shows the monthly mean CO₂-e data for Cape Grim from 2015 through to March 2019, showing CO₂-e surpassing 500ppm in July 2018.
CSIRO

This milestone, like so many others, is symbolic. The difference between 499 and 500ppm CO₂-e is marginal in terms of the fate of the climate and the life it sustains. But the fact that the cleanest air on the planet has now breached this threshold should elicit deep concern.

Warming on the way

The Paris climate agreement is aimed at limiting global warming to less than 2℃ above pre-industrial levels, to avoid the most dangerous effects of climate change. But the task of predicting how human greenhouse emissions will perturb the climate system on a scale of decades to centuries is complex.

The best estimate of long-term global warming expected from 500ppm CO₂-e is about 2.5℃. But so far, since pre-industrial times, the global climate (including oceans) has warmed by only 0.7℃.

This is partly because industrial smog and other tiny particles (together called aerosols) reflect sunlight out to space, offsetting some of the expected warming. What’s more, the climate system responds slowly to rising atmospheric greenhouse gas concentrations because much of the excess heat is taken up by the oceans.

The amount of heat each greenhouse gas can trap depends on its absorption spectrum – how strongly it can absorb energy at different wavelengths, particularly in the infrared range. Despite its simple molecular structure, there is still much to learn about the heat-absorbing properties of methane, the second-biggest component of CO₂-e.

Studies published in 2016 and 2018 led to the estimate of methane’s warming potential being revised upwards by 15%, meaning methane is now considered to be 32 times more efficient at trapping heat in the atmosphere than CO₂, on a per-molecule basis over a 100-year time span.

Considering this new evidence, we calculate that greenhouse gas concentrations at Cape Grim crossed the 500ppm CO₂-e threshold in July 2018.

This is higher than the official estimate based on the previous formulation for calculating CO₂-e, which remains in widespread use. For instance, the US National Oceanic and Atmospheric Administration is reporting 2018 CO₂-e as 496ppm.

The graph below shows the two curves for the time evolution of CO₂-e in the atmosphere as measured at Cape Grim, using the old and new formulae.

Cape Grim monthly CO2-e from 2015 until Sept 2018 calculated using the old and new formulae.
CSIRO

Some greenhouse gases, such as chlorofluorocarbons (CFCs), also deplete the ozone layer. CFCs are in decline thanks to the Montreal Protocol, which bans the production and use of these chemicals, despite reports that indicate some recent production of CFC-11 in China.

But unfortunately their ozone-safe replacements, hydrofluorocarbons (HFCs), are very potent greenhouse gases, and are on the rise. The recently enacted Kigali Amendment to the protocol means that consumption controls on HFCs are now in place, and this will see the growth rate of HFCs slow significantly and then reverse in the coming decades.

We can change

Australia is at the forefront of initiating measures to curb the impact of HFCs on climate change.

Methane is another low-hanging fruit for climate action, while we undertake the slower and more difficult transition away from CO₂-emitting energy sources.

The significant human methane emissions from leaks in reticulated gas systems, landfills, waste water treatment, and fugitive emissions from coal mining and oil and gas production can be monitored and reduced. We have the science and technology to do this now.

Both in the oil and gas sectors and in urban areas, there are many examples of how methane “hot spots” can be identified and tackled.

It’s a classic win-win that saves money and reduces climate change, and something we should be implementing in Australia in the near future.The Conversation

Zoe Loh, Research Scientist, CSIRO; Blagoj Mitrevski, Research scientist, CSIRO; David Etheridge, Principal Research Scientist, CSIRO; Nada Derek, Research Projects Officer, Oceans and Atmosphere, Climate Science Centre, CSIRO; Paul Fraser, Honorary Fellow, CSIRO; Paul Krummel, Research Group Leader, CSIRO; Paul Steele, Honorary Fellow, CSIRO; Ray Langenfelds, Scientist at CSIRO Atmospheric Research, CSIRO, and Sam Cleland, Officer in Charge, Cape Grim Baseline Air Pollution Station, Australian Bureau of Meteorology

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

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Whichever way you spin it, Australia’s greenhouse emissions have been climbing since 2015


Tim Baxter, University of Melbourne

Let me explain how to see through the spin on Australia’s rising greenhouse emissions figures.

With the release today of Australia’s emissions data for the December 2018 quarter, federal energy and emissions reduction minister Angus Taylor has been more forthcoming than usual about the rising trend in Australia’s emissions.

There’s one small issue, though. Despite Taylor’s comments in which he sought to explain away Australia’s 0.7% year-on-year rise in emissions as a product of increased gas investment, actual emissions in the December quarter were in fact down relative to the September 2018 quarter. This is due mainly to the fact that people use much more energy for heating in the July-September period than they do during the milder spring weather of October-December.

Taylor, meanwhile, was discussing the “adjusted” data, which reveals an 0.8% increase between the two quarters.

This might all sound like minor quibbling. But knowing the difference between quarterly and annual figures, and raw and adjusted data – and knowing what’s ultimately the most important metric – is crucial to understanding Australia’s emissions. And it might come in handy next time you’re listening to a politician discussing our progress (or lack thereof) towards tackling climate change.




Read more:
Australia is not on track to reach 2030 Paris target (but the potential is there)


Highlighting the difference between quarters is problematic, because emissions data are what statisticians describe as “noisy”. Emissions levels jump around from period to period, which can obscure the overall trend.

Quarterly data is important for understanding how Australia is tracking more generally towards doing its fair share on reducing its emissions. But too much stock is put on the noise, and not enough on the underlying trend.

The charts below compare our estimated actual emissions on a quarterly basis (top) with the cumulative emissions for the year leading up to that quarter (here described as the “year-to-quarter emissions” and shown in the lower chart).

Quarterly emissions. (LULUCF stands for Land use, land-use change, and forestry.)
Dept Environment and Energy (data)
Year-to-quarter emissions. (LULUCF stands for Land use, land-use change, and forestry.)
Dept Environment and Energy (data)

These charts, both built on today’s data, make a few things clear.

Quarterly emissions are noisy

The first thing to note is that saying that our emissions are down compared with the previous quarter is hardly remarkable, or worth patting ourselves on the back for. This is especially true if we are comparing the December quarter data, released today, with the data for the preceding quarter.

September quarter emissions are almost always higher than the rest of the year. This is because, while September itself is in spring, the September quarter also covers July and August.

Our winter heating needs are generally met using fossil fuels, whether through electric heaters or natural gas, which is why the September quarter has the highest emissions. In the December quarter, which covers most of spring, our need for heating drops, and so do our emissions.

But if you look beyond the difference between quarters, as in the second chart above, you can see the underlying rising trend in our greenhouse gas emissions.

Cherrypicking the best metric

Readers who follow climate politics may remember the spectacular moment in March when Taylor appeared on ABC’s Insiders opposite Barrie Cassidy.

Many journalists, including those on the Insiders panel that day, responded at the time that Taylor’s claim that emissions had dipped over the preceding three months was true but not meaningful, in the context of an annual rising trend.

But it was not even necessarily true. As is visible in the quarterly chart, emissions were not lower in the September quarter of 2018 than they were in the preceding quarter.

Specifically, Taylor claimed that “total emissions are coming down right now”. This is only true if we are talking about “seasonally adjusted, weather-normalised total emissions”. The adjusted data are shown above. While the adjusted data went down between quarters, the actual emissions went up.

The process of adjustment is not unprincipled, and is used to see through the noise of our emissions data. “Seasonal adjustment” and “weather normalisation” are two separate processes.

Seasonal adjustment refers to the process of adjusting the emissions figures to account for the predictable seasonal fluctuations described earlier. Weather normalisation does the same, but takes into account individual temperature extremes, both hot and cold, during any given period, and adjusts accordingly.

Much as a golf handicap lets us compare the performance of golfers of differing abilities, these data adjustments tell us whether our emissions are tracking higher or lower than we might expect.

But if a golfer with a handicap of 10 goes around the course in 82 shots, we don’t declare that they have actually hit the ball only 72 times.

This is essentially what Taylor did in his interview with Cassidy. It is not correct to refer to these adjusted emissions data as our “total emissions”.

What does data adjustment mean?

Building on this, it is important to note that the adjusted data and actual data often disagree on whether emissions have increased between quarters. Since the Coalition took office in 2013, there have been 21 quarterly emissions data releases.

The actual quarterly emissions have increased nine times between quarters. The adjusted data says there have been 12 of these increases. And they have only agreed on whether there was an increase six times.

When one form of the data shows an increase and the other does not, the minister has a choice about which figure to highlight.

In the September quarter, the actual emissions gave bad news (an increase), and the adjusted emissions gave good news (a reduction). Taylor chose to refer to the adjusted data, as did the then environment minister Melissa Price, who had portfolio responsibility for emissions reduction at the time.

Today, this was flipped. The actual emissions showed good news (a reduction) and the adjusted data showed bad news (an increase).

It’s refreshing, then, to see Taylor choose to focus on the adjusted emissions data this time around, when he could have chosen the spin route and focused on the fact that the raw data showed a decrease between quarters.

So what does it all mean?

What we can say without any equivocation at all is that since 2015, in the wake of the carbon price repeal the preceding July, Australia’s greenhouse emissions have increased. On the government’s own projections , this trend is not expected to change.

Even if the government’s Climate Solutions Package delivers the amount of emissions reductions that have been promised (and it is unclear that it will), the overall effect will be to stabilise emissions rather than bring them down. This is because the government intends to use Kyoto carryover credits to help meet its Paris Agreement goal, rather than using fresh carbon reductions to deliver in full.




Read more:
Australia has two decades to avoid the most damaging impacts of climate change


Stabilisation is not enough. As the Intergovernmental Panel on Climate Change made clear in its Special Report on 1.5℃ last year, deep cuts are required to ensure a safe climate. The Paris Agreement, while calling on all nations to do their part, says rich countries such as Australia should take the lead.

The need to reduce emissions is pressing. And while the raw emissions figures may be down this quarter, this is not meaningful progress. Far more meaningful is the fact that Australia has no effective policy to limit our impact on the global climate.The Conversation

Tim Baxter, Fellow – Melbourne Law School; Associate – Australian-German Climate and Energy College, University of Melbourne

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

Australians could have saved over $1 billion in fuel if car emissions standards were introduced 3 years ago



Legislative action regarding vehicle emissions is overdue, and needs urgent attention by the federal government.
Shutterstock

Robin Smit, The University of Queensland; Jake Whitehead, The University of Queensland, and Nic Surawski, University of Technology Sydney

When it comes to road transport, Australia is at risk of becoming a climate villain as we lag behind international best practice on fuel efficiency.

Road transport is one of the main sources of greenhouse gas emissions and represented 16% of Australia’s total carbon dioxide emissions in 2000, growing to 21% in 2016. Total CO₂ emissions from road transport increased by almost 30% in the period 2000-16.

Fuel efficiency (CO₂ emission) standards have been adopted in around 80% of the global light vehicle market to cap the growth of transport emissions. This includes the United States, the European Union, Canada, Japan, China, South Korea and India – but not Australia.




Read more:
Emissions standards on cars will save Australians billions of dollars, and help meet our climate targets


If Australia had introduced internationally harmonised emissions legislation three years ago, households could have made savings on fuel costs to the tune of A$1 billion.

This shocking figure comes from our preliminary calculations looking at the effect of requiring more efficient vehicles to be sold in Australia.

A report, published yesterday by Transport Energy/Emission Research, looked at what Australia has achieved in vehicle fuel efficiency and CO₂ standards over the past 20 years. While Australia has considered and tried to impose standards a number of times, sadly these attempts were unsuccessful.

Legislative action on vehicle CO₂ emissions is long overdue and demands urgent attention by the Australian government.

Australian consumers are increasingly buying heavier vehicles with bigger emissions.
Shuterstock

How did Australia get here?

The most efficient versions of vehicle models offered in Australia are considerably less efficient than similar vehicles in other markets.

Australia could increasingly become a dumping ground for the world’s least efficient vehicles with sub-par emissions performance, given our lack of fuel efficiency standards. This leaves us on a dangerous path towards not only higher vehicle emissions, but also higher fuel costs for passenger travel and freight.

Australia has attempted to impose CO₂ or fuel efficiency standards on light vehicles several times over the past 20 years, but without success. While the federal government was committed to addressing this issue in 2015, four years later we are still yet to hear when – or even if – mandatory fuel efficiency standards will ever be introduced.

The general expectation appears to be that average CO₂ emission rates of new cars in Australia will reduce over time as technology advances overseas. In the absence of CO₂ standards locally, it is more likely that consumers will continue to not be offered more efficient cars, and pay higher fuel costs as a consequence.

Estimating the fuel savings

Available evidence suggests Australian motorists are paying on average almost 30% more for fuel than they should because of the lack of fuel efficiency standards.

The Australian vehicle fleet uses about 32 billion litres of fuel per year.

Using an Australian fleet model described in the TER report, we can make a conservative estimate that the passenger vehicle fleet uses about half of this fuel: 16 billion litres per year. New cars entering the fleet each year would represent about 5% of this: 800 million litres per year.

So assuming that mandatory CO₂ standards improve fuel efficiency by 27%, fuel savings would be 216 million litres per year.

In the last three years, the average fuel price across Australia’s five major cities is A$1.33 per litre. This equates to a total savings of A$287 million per year, although this would be about half the first year as new cars are purchased throughout the year and travel less, and would reduce as vehicles travel less when they age.

The savings are accumulative because a car purchased in a particular year continues to save fuel over the following years.

The table below shows a rough calculation of savings over the three year period (2016-2018), for new cars sold in the same period (Model Years 2016, 2017 and 2018).

As a result, over a period of three years, A$1.3 billion in potential savings for car owners would have accumulated.

Policy has come close, but what are we waiting for?

The Australian government is not progressing any measures to introduce a fuel efficiency target. In fact, it recently labelled Labor’s proposed fuel efficiency standard as a “car tax”.

But Australia has come close to adopting mandatory vehicle CO₂ emission standards in the past.

In late 2007, the Labor government committed to cutting emissions to achieve Australia’s obligations under the Kyoto Protocol. The then prime minister, Kevin Rudd, instructed the Vehicle Efficiency Working Group to:

… develop jointly a package of vehicle fuel efficiency measures designed to move Australia towards international best practice.

Then, in 2010, the Labor government decided mandatory CO₂ emissions standards would apply to new light vehicles from 2015. But a change in government in 2013 meant these standards did not see the light of day.

The amount of fuel that could have been saved is A$287 million per year.
Shutterstock

Things looked promising again when the Coalition government released a Vehicle Emissions Discussion Paper in 2016, followed by a draft Regulation Impact Statement in the same year.

The targets for adopting this policy in 2025, considered in the draft statement, were marked as “strong” (105g of CO₂ per km), “medium” (119g/km) and “mild” (135g/km) standards.

Under all three targets, there would be significant net cost savings. But since 2016, the federal government has taken no further action.

It begs the question: what exactly are we waiting for?

The technical state of play

Transport Energy/Emission Research conducted preliminary modelling of Australian real-world CO₂ emissions.

This research suggests average CO₂ emission rates of the on-road car fleet in Australia are actually increasing over time and are, in reality, higher than what is officially reported in laboratory emissions tests.

In fact, the gap between mean real-world emissions and the official laboratory tests is expected to grow from 20% in 2010 to 65% in 2025.

This gap is particularly concerning when we look at the lack of support for low-emissions vehicles like electric cars.




Read more:
Why battery-powered vehicles stack up better than hydrogen


Given that fleet turnover is slow, the benefits of fuel efficiency standards would only begin to have a significant effect several years into the future.

With continuing population growth, road travel will only increase further. This will put even more pressure on the need to reduce average real-world CO₂ emission rates, given the increasing environmental and health impacts of the vehicle fleet.

Even if the need to reduce emissions doesn’t convince you, the cost benefits of emissions standards should. The sale of less efficient vehicles in Australia means higher weekly fuel costs for car owners, which could be avoided with the introduction of internationally harmonised emissions legislation.The Conversation

Robin Smit, Adjunct professor, The University of Queensland; Jake Whitehead, Research Fellow, The University of Queensland, and Nic Surawski, Lecturer in Environmental Engineering, University of Technology Sydney

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

Eastern China pinpointed as source of rogue ozone-depleting emissions



Sunset at Australia’s Cape Grim observatory, one of the key global background monitoring sites for CFC-11.
Paul Krummel/CSIRO, Author provided

Paul Krummel, CSIRO; Bronwyn Dunse, CSIRO; Nada Derek, CSIRO; Paul Fraser, CSIRO, and Paul Steele, CSIRO

A mysterious rebound in the emissions of ozone-depleting chemicals – despite a global ban stretching back almost a decade – has been traced to eastern China.

Research published by an international team today in Nature used a global network of monitoring stations to pinpoint the source of the rogue emissions. According to these data, 40-60% of the increase in emissions seen since 2013 is due to possibly illegal industrial activity in the Chinese provinces of Shandong and Hebei.




Read more:
After 30 years of the Montreal Protocol, the ozone layer is gradually healing


Chlorofluorocarbon-11 (CFC-11) is a powerful ozone-depleting chemical that plays a major role in the appearance, each spring, of the ozone “hole” over Antarctica.

In the past, CFC-11 had been used primarily as a propellant in aerosol products and as a foam plastic blowing agent. The production and consumption (use) of CFC-11 are controlled by the global Montreal Protocol. CFC-11 consumption has been banned in developed countries since 1996, and worldwide since 2010.

This has resulted in a significant decline of CFC-11 in the atmosphere. Long-term CFC-11 measurements at Cape Grim, Tasmania, show the amount in the atmosphere peaked in 1994, and fell 14% by 2018.

However, this decline has not been as rapid as expected under the global zero production and consumption mandated by the Montreal Protocol since 2010.

Background levels of CFC-11 measured at Australia’s Cape Grim Baseline Air Pollution Station, located at the north-west tip of Tasmania.
CSIRO/Bureau of Meteorology

A 2014 study was the first to deduce that global emissions of CFC-11 stopped declining in 2002. In 2015, CSIRO scientists advised the Australian government, based on measurements compiled by the Advanced Global Atmospheric Gases Experiment (AGAGE), which includes those from Cape Grim, that emissions had risen significantly since 2011. The cause of this rebound in CFC-11 emissions was a mystery.

Global CFC-11 emissions based on atmospheric measurements compared with the expected decline of this compound in the atmosphere if compliance with the Montreal Protocol was adhered to.
CSIRO/AGAGE

An initial explanation came in 2018, when researchers led by Stephen Montzka of the US National Oceanic and Atmospheric Administration analysed the CFC-11 data collected weekly at Mauna Loa, Hawaii. They deduced that the increased emissions originated largely from East Asia – likely as a result of new, illegal production.

Montzka’s team concluded that if these increased CFC-11 emissions continued, the closure of the Antarctic ozone hole could be delayed, possibly for decades. This was a remarkable piece of detective work, considering that Mauna Loa is more than 8,000km from East Asia.

Suspicions confirmed

A still more detailed explanation is published today in the journal Nature by an international research team led by Matt Rigby of the University of Bristol, UK, and Sunyoung Park of Kyungpook National University, South Korea, together with colleagues from Japan, the United States, Australia and Switzerland. The new study uses data collected every two hours by the AGAGE global monitoring network, including data from Gosan, South Korea, and from an AGAGE-affiliated station at Hateruma, Japan. Crucially, Gosan and Hateruma are just 1,000km and 2,000km, respectively, from the suspected epicentre of CFC-11 emissions in East Asia.

The Korean and Japanese data show that these new emissions of CFC-11 do indeed come from eastern China – in particular the provinces of Shandong and Hebei – and that they have increased by around 7,000 tonnes per year since 2013.

Meanwhile, the rest of the AGAGE network has detected no evidence of increasing CFC-11 emissions elsewhere around the world, including in North America, Europe, Japan, Korea or Australia.

Yet while this new study has accounted for roughly half of the recent global emissions rise, it is possible that smaller increases have also taken place in other countries, or even in other parts of China, not covered by the AGAGE network. There are large swathes of the globe for which we have very little detailed information on CFC emissions.

Map showing the region where the increased CFC-11 emissions came from, based on atmospheric measurements and modelling.
University of Bristol/CSIRO

Nevertheless, this study represents an important milestone in atmospheric scientists’ ability to tell which regions are emitting ozone-depleting substances and in what quantities. It is now vital we find out which industries are responsible for these new emissions.

If the emissions are due to the manufacture and use of products such as foams, it is possible that, so far, we have seen in the atmosphere only a fraction of the total amount of CFC-11 that was produced illegally. The remainder could be locked up in buildings and chillers, and will ultimately be released to the atmosphere over the coming decades.




Read more:
Explainer: what is the Antarctic ozone hole and how is it made?


While our new study cannot determine which industry or industries are responsible, it does provide strong evidence that substantial new emissions of CFC-11 have occurred from China. Chinese authorities have identified, and closed down, some illegal production facilities over the past several years.

This study highlights the importance of undertaking long-term measurements of trace gases like CFC-11 to verify that international treaties and protocols are working. It also identifies shortcomings in the global networks for detecting regional emissions of ozone depleting substances. This should encourage expansion of these vital measurement networks which would lead to a capability of more rapid identification of future emission transgressions.The Conversation

Paul Krummel, Research Group Leader, CSIRO; Bronwyn Dunse, Climate Science Centre, CSIRO Oceans and Atmosphere, CSIRO; Nada Derek, Centre for Australian Weather and Climate Research, CSIRO; Paul Fraser, Honorary Fellow, CSIRO, and Paul Steele, Centre for Australian Weather and Climate Research, CSIRO

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

Turning methane into carbon dioxide could help us fight climate change



It’s not cows’ fault they fart, but the methane they produce is warming the planet.
Robert Bye/Unsplash

Pep Canadell, CSIRO and Rob Jackson, Stanford University

Discussions on how to address climate change have focused, very appropriately, on reducing greenhouse gas emissions, particularly those of carbon dioxide, the major contributor to climate change and a long-lived greenhouse gas. Reducing emissions should remain the paramount climate goal.

However, greenhouse gas emissions have been increasing now for two centuries. Damage to the atmosphere is already profound enough that reducing emissions alone won’t be enough to avoid effects like extreme weather and changing weather patterns.

In a paper published today in Nature Sustainability, we propose a new technique to clean the atmosphere of the second most powerful greenhouse gas people produce: methane. The technique could restore the concentration of methane to levels found before the Industrial Revolution, and in doing so, reduce global warming by one-sixth.

Our new technique sounds paradoxical at first: turning methane into carbon dioxide. It’s a concept at this stage, and won’t be cheap, but it would add to the tool kit needed to tackle climate change.

The methane menace

After carbon dioxide, methane is the second most important greenhouse gas leading to human-induced climate change. Methane packs a climate punch: it is 84 times more powerful than carbon dioxide in warming the planet over the first 20 years of its molecular life.




Read more:
Methane is a potent pollutant – let’s keep it out of the atmosphere


Methane emissions from human activities are now larger than all natural sources combined. Agriculture and energy production generate most of them, including emissions from cattle, rice paddies and oil and gas wells.

The result is methane concentrations in the atmosphere have increased by 150% from pre-industrial times, and continue to grow. Finding ways to reduce or remove methane will therefore have an outsize and fast-acting effect in the fight against climate change.


Global Carbon Atlas

What we propose

The single biggest challenge for removing methane from the atmosphere is its low concentration, only about 2 parts per million. In contrast, carbon dioxide is now at 415 parts per million, roughly 200 times higher. Both gases are much more diluted in air than when found in the exhaust of a car or in a cow’s burp, and both would be better served by keeping them out of the atmosphere to start with.

Nonetheless, emissions continue. What if we could capture the methane after its release and convert it into something less damaging to climate?




Read more:
What is a pre-industrial climate and why does it matter?


That is why our paper proposes removing all methane in the atmosphere produced by human activities – by oxidising it to carbon dioxide. Such an approach has not been proposed before: previously, all removal techniques have only been applied to carbon dioxide.

This is the equivalent of turning 3.2 billion tonnes of methane into 8.2 billion tonnes of carbon dioxide (equivalent to several months of global emissions). The surprising aspect to this trade is that it would reduce global warming by 15%, because methane is so much more warming than carbon dioxide.

Proposed industrial array to oxidise methane to carbon dioxide.
Jackson et al. 2019 Nature Sustainability

This reaction yields energy rather than requires it. It does require a catalyst, though, such as a metal, that converts methane from the air and turns it into carbon dioxide.

One fit-for-purpose family of catalysts are zeolites. They are crystalline materials that consist of aluminum, silicon and oxygen, with a very porous molecular structure that can act as a sponge to soak up methane.

They are well known to industrial researchers trying to oxidise methane to methanol, a valuable chemical feedstock.

We envision arrays of electric fans powered by renewable energy to force large volumes of air into chambers, where the catalyst is exposed to air. The catalyst is then heated in oxygen to form and release CO₂. Such arrays of fans could be placed anywhere where renewable energy – and enough space – is available.

We calculate that with removal costs per tonne of CO₂ rising quickly from US$50 to US$500 or more this century, consistent with mitigation scenarios that keep global warming below 2℃, this technique could be economically feasible and even profitable.

We won’t know for sure, though, until future research highlights the precise chemistry and industrial infrastructure needed.

Beyond the clean-up we propose here, methane removal and atmospheric restoration could be an extra tool in humanity’s belt as we aim for stringent climate targets, while providing new economic opportunities.




Read more:
Why methane should be treated differently compared to long-lived greenhouse gases


Future research and development will determine the technical and economic feasibility of methane removal. Even if successful, methane- and other carbon-removal technologies are no substitute for strong and rapid emissions reductions if we are to avoid the worst impacts of global warming.The Conversation

Pep Canadell, Chief research scientist, CSIRO Oceans and Atmosphere; and Executive Director, Global Carbon Project, CSIRO and Rob Jackson, Chair, Department of Earth System Science, and Chair of the Global Carbon Project, globalcarbonproject.org, Stanford University

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

NZ introduces groundbreaking zero carbon bill, including targets for agricultural methane



Agriculture – including methane from cows and sheep – currently contributes almost half of New Zealand’s greenhouse emissions.
from http://www.shutterstock.com, CC BY-ND

Robert McLachlan, Massey University

New Zealand’s long-awaited zero carbon bill will create sweeping changes to the management of emissions, setting a global benchmark with ambitious reduction targets for all major greenhouse gases.

The bill includes two separate targets – one for the long-lived greenhouse gases carbon dioxide and nitrous oxide, and another target specifically for biogenic methane, produced by livestock and landfill waste.

Launching the bill, Prime Minister Jacinda Ardern said:

Carbon dioxide is the most important thing we need to tackle – that’s why we’ve taken a net zero carbon approach. Agriculture is incredibly important to New Zealand, but it also needs to be part of the solution. That is why we have listened to the science and also heard the industry and created a specific target for biogenic methane.

The Climate Change Response (Zero Carbon) Amendment Bill will:

  • Create a target of reducing all greenhouse gases, except biogenic methane, to net zero by 2050
  • Create a separate target to reduce emissions of biogenic methane by 10% by 2030, and 24-47% by 2050 (relative to 2017 levels)
  • Establish a new, independent climate commission to provide emissions budgets, expert advice, and monitoring to help keep successive governments on track
  • Require government to implement policies for climate change risk assessment, a national adaptation plan, and progress reporting on implementation of the plan.



Read more:
Climate change is hitting hard across New Zealand, official report finds


Bringing in agriculture

Preparing the bill has been a lengthy process. The government was committed to working with its coalition partners and also with the opposition National Party, to ensure the bill’s long-term viability. A consultation process in 2018 yielded 15,000 submissions, more than 90% of which asked for an advisory, independent climate commission, provision for adapting to the effects of climate change and a target of net zero by 2050 for all gasses.

Throughout this period there has been discussion of the role and responsibility of agriculture, which contributes 48% of New Zealand’s total greenhouse gas emissions. This is an important issue not just for New Zealand and all agricultural nations, but for world food supply.


Ministry for the Environment, CC BY-ND

Another critical question involved forestry. Pathways to net zero involve planting a lot of trees, but this is a short-term solution with only partly understood consequences. Recently, the Parliamentary Commissioner for the Environment suggested an approach in which forestry could offset only agricultural, non-fossil emissions.

Now we know how the government has threaded its way between these difficult choices.




Read more:
NZ’s environmental watchdog challenges climate policy on farm emissions and forestry offsets


Separate targets for different gases

In signing the Paris Agreement, New Zealand agreed to hold the increase in the global average temperature to well below 2°C and to make efforts to limit it to 1.5°C. The bill is guided by the latest Intergovernmental Panel on Climate Change (IPCC) report, which details three pathways to limit warming to 1.5°C. All of them involve significant reductions in agricultural methane (by 23%-69% by 2050).

Farmers will be pleased with the “two baskets” approach, in which biogenic methane is treated differently from other gasses. But the bill does require total biogenic emissions to fall. They cannot be offset by planting trees. The climate commission, once established, and the minister will have to come up with policies that actually reduce emissions.

In the short term, that will likely involve decisions about livestock stocking rates: retiring the least profitable sheep and beef farms, and improving efficiency in the dairy industry with fewer animals but increased productivity on the remaining land. Longer term options include methane inhibitors, selective breeding, and a possible methane vaccine.

Ambitious net zero target

Net zero by 2050 on all other gasses, including offsetting by forestry, is still an ambitious target. New Zealand’s emissions rose sharply in 2017 and effective mechanisms to phase out fossil fuels are not yet in place. It is likely that with protests in Auckland over a local 10 cents a litre fuel tax – albeit brought in to fund public transport and not as a carbon tax per se – the government may be feeling they have to tread delicately here.

But the bill requires real action. The first carbon budget will cover 2022-2025. Work to strengthen New Zealand’s Emissions Trading Scheme is already underway and will likely involve a falling cap on emissions that will raise the carbon price, currently capped at NZ$25.




Read more:
Why NZ’s emissions trading scheme should have an auction reserve price


In initial reaction to the bill, the National Party welcomed all aspects of it except the 24-47% reduction target for methane, which they believe should have been left to the climate commission. Coalition partner New Zealand First is talking up their contribution and how they had the agriculture sector’s interests at heart.

While climate activist groups welcomed the bill, Greenpeace criticised the bill for not being legally enforceable and described the 10% cut in methane as “miserly”. The youth action group Generation Zero, one of the first to call for zero carbon legislation, is understandably delighted. Even so, they say the law does not match the urgency of the crisis. And it’s true that since the bill was first mooted, we have seen a stronger sense of urgency, from the Extinction Rebellion to Greta Thunberg to the UK parliament’s declaration of a climate emergency.




Read more:
UK becomes first country to declare a ‘climate emergency’


New Zealand’s bill is a pioneering effort to respond in detail to the 1.5ºC target and to base a national plan around the science reported by the IPCC.

Many other countries are in the process of setting and strengthening targets. Ireland’s Parliamentary Joint Committee on Climate recently recommended adopting a target of net zero for all gasses by 2050. Scotland will strengthen its target to net zero carbon dioxide and methane by 2040 and net zero all gasses by 2045. Less than a week after this announcement, the Scottish government dropped plans to cut air departure fees (currently £13 for short and £78 for long flights, and double for business class).

One country that has set a specific goals for agricultural methane is Uruguay, with a target of reducing emissions per kilogram of beef by 33%-46% by 2030. In the countries mentioned above, not so different from New Zealand, agriculture produces 35%, 23%, and 55% of emissions, respectively.

New Zealand has learned from processes that have worked elsewhere, notably the UK’s Climate Change Commission, which attempts to balance science, public involvement and the sovereignty of parliament. Perhaps our present experience in balancing the demands of different interest groups and economic sectors, with diverse mitigation opportunities and costs, can now help others.The Conversation

Robert McLachlan, Professor in Applied Mathematics, Massey University

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

Shorten’s climate policy would hit more big polluters harder and set electric car target


Michelle Grattan, University of Canberra

A Shorten government would add about 100 high polluters to those subject to an emissions cap, and drastically slash the present cap’s level, under the opposition’s climate policy released on Monday.

Labor would aim for a new threshold under a revamp of the existing safeguards mechanism of 25,000 tonnes of direct carbon dioxide pollution annually, which would be phased in after consultation with industry.

This would be a major reduction from the current cap of 100,000 tonnes. About 140 to 160 polluters come under the existing cap.

The safeguards mechanism was established by the Coalition government to cap pollution for the biggest polluters by setting limits or “baselines” for facilities covered. But Labor says it has been ineffective.

On transport, the policy sets an ambitious target of having electric vehicles form 50% of new car sales by 2030. The government fleet would have an electric vehicle target of 50% of new purchases and leases of passenger vehicles by 2025.

The climate change policy covers industry, transport and agriculture, with the proposed measures for the electricity sector, including an in-principle commitment to a national energy guarantee (NEG) and subsidies for batteries, already announced.

The agriculture sector would not be covered by the expanded safeguards policy.

The government’s emissions reduction fund – recently allocated a further A$2 billion over a decade and renamed – would be scrapped if Labor wins the May election.

The climate policy is the third of three key policy announcements the opposition wanted to make before the election is called, likely next weekend. The others were the wages policy and the announcement of the start date – January 1 – for the proposed crackdown on negative gearing.

The opposition has committed itself to a 45% economy-wide reduction in emissions relative to 2005 levels by 2030, compared with the government’s commitment to a reduction of 26-28%.

Labor’s policy confirms that it would not use Australia’s credits from the expiring Kyoto Protocol to help meet its Paris target, saying this course is “fake action on climate change”. Bill Shorten said on Sunday: “It’s only the Australian Liberal Party and the Ukraine proposing to use these carryover credits that I am aware of.”

Labor says it would “work in partnership with business to help bring down pollution.”

“Labor’s approach isn’t about punishing polluters. It’s about partnering with industry to find real, practical solutions to cut pollution, in a way that protects and grows industry and jobs.”

“There will be no carbon tax, carbon pricing mechanism, or government revenue,” Labor says.

“Rather, Labor will reduce pollution from the biggest industrial polluters by extending the existing pollution cap implemented by Malcolm Turnbull.”

“Pollution caps will be reduced over time and Labor will make it easier for businesses to meet these caps by allowing for industrial and international offsets.”

The expanded scheme’s new threshold would capture an estimated 250 of the biggest industrial polluters – 0.01% of all businesses.

Businesses would be able to earn credits for “overachievement” – reducing pollution below their baselines. They could sell these credits or use them to meet their future cap.

“Tailored” treatment would be provided to emissions-intensive trade-exposed industries (EITEs) such as steel, aluminium and cement. There would be a A$300 million Strategic Industries Reserve Fund “to support these industries in finding solutions to cut pollution and remain competitive”.

A Shorten government would consult with industry and experts on baselines for individual entities and the timing of reduction.

It would also put in place “a well-functioning offset market and reinvigorate the land offset market”.

“Currently, a facility that emits more than its baseline must offset excess emissions by purchasing offsets, primarily from the land sector. But currently businesses cannot access international offsets, or offsets from the electricity sector.

“Labor will make it easier for covered businesses to meet any offset obligations, not only by allowing for the creation and sale of offsets if emissions fall below baselines, but also through the purchase of international offsets and potentially offsets from the electricity sector.

“We will also boost offset supply through revitalising the Carbon Farming Initiative (CFI) – including reforms to strengthen the integrity of the CFI, and increasing land and other sector abatement opportunities.

“This will include exploring the establishment of ‘premium’ land sector credits to provide substantial environmental, biodiversity and other co-benefits, establishing a Carbon Assessment Standard to boost the bankability of offset projects, and re-vitalising offset methodology research and development with an additional A$40 million in funding over four years.

“Labor’s plan will help industry reduce pollution at least cost, and give traditional owners, farmers, the forestry industry and traditional owners new opportunities to earn income.”

On transport – which accounts for nearly 20% of Australia’s emissions – Labor says Australia is now last among western countries for electric vehicle uptake.

“Setting a national target will deliver more affordable electric vehicles into the Australian market and drive the switch to electric vehicles, reducing their cost, creating thousands of jobs and cutting pollution.”

Businesses would get an upfront tax deduction to buy electric vehicles, as part of the ALP’s announced Australian Investment Guarantee.

One aspect of moving quickly to government electric vehicle fleets would be that it would develop a secondhand market, Labor says.

“Labor will also work with industry to introduce vehicle emissions standards, to save Australian motorists hundreds of dollars each year at the bowser while driving down pollution on our roads.

“Australia is now one of the only developed nations without vehicle emissions standards in place. As a result, motorists will pay as much as A$500 each year more at the bowser than they should be, as well as seeing pollution on our roads skyrocket.

“Labor will consult on the timeline and coverage of vehicle emission standards to ensure consumers are made significantly better off, and aim to phase-in standards of 105g CO₂/km for light vehicles, which is consistent with Climate Change Authority advice.”

These standards would be in line with those in the United States but less stringent than those in the European Union.

“These standards will be applied to car retailers to meet average emissions standards, rather than imposing blanket mandatory standards on manufacturers.

“This will allow retailers to meet the standards by offsetting high emissions car sales with low or zero emissions car sales – such as electric vehicles.”



Emily Nunell/Michael Hopkin/The Conversation, CC BY-ND

UPDATE: Reaction

The government has reacted predictably to the Labor climate plan, branding it a “new tax”, ahead of what will be a major Coalition scare campaign in the election.

Scott Morrison said the opposition leader “does not have a plan, he just has another tax.

“What we’ve got here is a ‘re-Rudd’ of a failed policy that costs jobs, that costs businesses, that will cost Australians at least $9,000 a year, with the reckless targets that Bill Shorten will make law.”

On electric cars, Morrison said Shorten needed to explain how in 10 years he would take them from 0.2% of the market to 50% – because if he didn’t achieve his “reckless target […] he has to come back and get that money off you”.

Energy Minister Angus Taylor said the Shorten policy “would be a wrecking ball in the economy.

“It would raise the price of electricity and the price of gas and the price of food and the price of cars. Labor needs to come clean on the detail – not just the mechanism, which we know is the carbon tax.”

The Business Council of Australia welcomed the further details Labor had provided but said there were unanswered questions including “what mechanism will drive and manage the transition to lower-emissions generation in the electricity sector?”

“It remains unclear how abatement will be delivered in the electricity sector and how the various announcements made today will contribute to an economy-wide emissions reduction target,” the BCA said.

It said it had strongly supported the National Energy Guarantee (NEG) and called on the ALP, if elected, “to commit to working with the states and territories to implement the scheme as a credible, market-based mechanism to drive abatement and investment in the electricity sector.”

The Labor party has supported in principle a NEG – the plan the Coalition dumped because of an internal split over it.

The Australian Conservation Foundation gave Labor’s policy a qualified tick, describing it as “a serious policy response to the existential threat of global warming that recognises pollution must be cut across all industry sectors.”

“Labor’s climate change plan does address many of the important challenges Australia has in transforming into a zero-pollution economy,” the ACF said.

But “unfortunately, sections of Labor’s policy platform contain significant wriggle room that big polluters may seek to exploit.

“If it wins government Labor must quickly harden the detail around its policies and resist attempts of industry lobby groups like the Minerals Council of Australia, the Business Council of Australia and the Australian Automobile Association to weaken climate action.”The Conversation

Michelle Grattan, Professorial Fellow, University of Canberra

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