What does the Global Carbon Budget result mean?

Today’s updated Global Carbon Budget shows nations – particularly developed economies – continue to release greenhouse gases from fossil fuels at record levels.

For decades, national governments have said they would reduce carbon emissions. It’s not happening.

Australia is, notably, trending down in its annual fossil carbon dioxide emissions. The carbon budget update shows it was one of just two big emitters (the other being Vietnam) to continue decreasing fossil carbon dioxide CO2 levels in 2021.  

But, globally, the picture is dire.

This report – with contributions from over 100 scientists affiliated to 80 leading universities and climate research institutes, including Australia’s CSIRO, Western Sydney University, and Antarctic Partnership Program – shows that after a dip in carbon emissions in 2020 (due to widespread COVID-19 lockdowns), the world has returned to business-as-usual carbon output. After rising in 2021, carbon dioxide is expected to surpass pre-COVID levels this year.

S20 total aus
Australia is one of two major polluters to reduce its carbon dioxide emissions in consecutive years. All other major emitters’ CO2 levels increased in 2021. Credit: Global Carbon Project

The report is a troublingly conservative snapshot of global carbon output. It relies partly on self-reported national emissions data, and it doesn’t include data on methane – another greenhouse gas which, while shorter-lived in the atmosphere, is 25 times more potent at trapping heat than carbon dioxide.

Read more: Satellite data indicate methane emissions in Australia’s coal sector are extremely high

There is one glimmer of good news, although the data is less reliable: carbon emissions from land use change (like deforestation, wetland modification and peatland destruction) continues to decline globally. This is partly because restorative measures are counteracting damaging actions.

While slow, Australia appears to be turning its ship around

Australia often spruiks the opportunities renewable energy presents to its large, sun and wind exposed continent.

The current Labor government promises a future where Australia would be a ‘renewable energy superpower’, their Liberal-National Party predecessors spoke of technology providing the path to emissions reduction.

But from its earliest involvement in global climate policy negotiations at Kyoto in 1997, Australia’s attitude to greenhouse gas reduction has been mixed. There, it successfully argued for a clause to count high-carbon land use and forestry emissions in its 1990 benchmark – a neat piece of negotiation that included old carbon output from industries that, by the time Kyoto was signed, had been in significant emissions decline.

Australia, Norway and Iceland also negotiated a Kyoto target that left them as the only developed economies allowed to increase their emissions relative to 1990.

In the years since, elections have been won and lost on climate: emissions trading schemes and carbon pollution taxes have been on the table, off the table, legislated and repealed.

“A lot needs to change in Australia’s emissions profile in order to achieve that 2030 target.”

Professor Frank Jotzo

This year, Australia legislated a net zero by 2050 target and a 43 percent carbon reduction target (relative to a 2005 benchmark) by the end of the decade. Many climate scientists believe this is too conservative. The government says it’s a minimum expectation.

Australia remains one of the world’s biggest fossil fuel exporters, the overseas burning of which does not count towards the nation’s output tally (and likened by UNSW Climate Justice Project lead Professor Jeremy Moss to a ‘gun dealer’s defence’).

Methane gas – not counted in the Global Carbon Budget – is prominent in Australia’s export and domestic electricity generation. While escaped carbon dioxide emissions are included in the data (such ‘fugitive’ emissions are those which escape containment), fugitive methane is not. Australia is a world leader in fugitive emissions as a proportion of its total greenhouse gas output.

In a briefing to journalists prior to the Budget’s release, climate experts noted the pandemic has disrupted some energy use trends. As the world returns increasingly to pre-pandemic normality, those downward trends need to hold firm.

“A lot needs to change in Australia’s emissions profile in order to achieve that 2030 target,” says Director of the Centre for Climate and Energy Policy at The Australian National University, Professor Frank Jotzo.

“Electricity, where we’re seeing these sustained emission reductions [is being driven by] a very substantial shift away from coal-fired generation.

“Coal [is] trending down really quickly, and that is made for by increases in renewable energy, principally solar, as well as wind… we expect that to continue, we expect that, in fact, to accelerate, with it being clear now that several of the major coal-fired power stations will be shutting down in coming years.

“That will be replaced very largely with renewable energy, and will lead to significant emissions reductions.”

What is less clear to Jotzo, and others, is what the post-2020 rebound will do in other sectors.

What he notes as the ‘COVID effect’ trimming carbon output across all sectors, may not mean all sources of greenhouse gas emissions share electricity’s trajectory. Many experts believe that industries like transportation will return to pre-pandemic carbon levels, with electric vehicles and public transport required at scale to prevent this. 

Bushfire damaged trees
Climate change will exacerbate natural hazards like wildfires (the damage pictured above occurred on Kangaroo Island, Australia in 2020), floods, cyclones, droughts and ocean acidification. Credit Lisa Maree Williams/Getty Images

A record year for CO2

Carbon dioxide in the atmosphere is more than 50% higher than pre-industrial levels.

As the primary accelerant of climate change, CO2 emissions from human sources like energy production, transport and agriculture pose the single biggest risk to the world exceeding the targets laid out in the Paris Climate Agreement (preferably no more than 1.5 degrees, and a hard limit of two degrees of post-industrial global warming).

The consequences, as indicated by the most recent Intergovernmental Panel on Climate Change (IPCC) report on the physical science of climate change, are disastrous.

At 1.5, it projects increased heat waves, longer warm seasons and shorter cold seasons across all parts of the globe. At two degrees, all regions can expect heat extremes to exceed tolerances for safe agriculture and health.

This brings with it new challenges. Carbon can be captured and stored by trees and vegetation, wetlands and oceans, but as the planet warms, these become less efficient. It means that even our natural weapons for limiting carbon escape are less effective.

Climate scientists and policy experts have made the enormity of the task facing the planet clear: If the world is to reach net zero carbon emissions by 2050, collectively, humans need to reduce their carbon output by around 1.4 gigatons of carbon dioxide annually.

That’s a COVID-lockdown year’s worth of reduced carbon, every year, for the next 27 years. Given nations’ inability to shake their reliance on coal, oil and gas, that seems unlikely.

It means the thresholds set out in the Paris Agreement are closing fast: For all the net zero by 2050 aspirations, hitting two degrees of warming around the same time means nations will fail to achieve the goals of Paris.

“Starting next year, we have nine years left if we stay with the same level of emissions to reach 1.5 [degrees] with a 50% likelihood,” says the CSIRO’s Global Carbon Project executive director Dr Pepe Canadell.

“[We have] 18 years for 1.7 [degrees], 30 years for two degrees.”

Climate scientists and policy experts have made the enormity of the task facing the planet clear: If the world is to reach net zero carbon emissions by 2050, collectively, humans need to reduce their carbon output by around 1.4 gigatons of carbon dioxide annually.

Canadell makes a very clear point. These milestones are based on where the world stands today, at a record 417 parts per million carbon dioxide in the atmosphere: “not projections, this is not what governments do or don’t do, this is from where we are now”.

See more COP27 coverage

In Egypt, climate diplomats representing nearly 200 countries are discussing how the commitments of last year’s Glasgow Climate Pact will be enacted. Developing nations are seeking firm commitments from the world’s developed economies around the financing of adaptation measures (according to the UN, emissions from the wealthiest one percent of people on the planet are more than the poorest half of the global population).  There will also be discussions around reducing the risk of loss and damage – events where adaptation is insufficient to prevent the destructive effects of climate change.

Clearly, though, the decarbonisation call from non-governmental actors – be they the UN, climate analysts, scientists and economists, or other observers – will continue to ring until the shared trajectory of carbon output heads south.

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