Climate and Environment

Climate: Removing CO2 from the air no longer optional

Marlowe Hood - Agence France-Presse
Climate: Removing CO2 from the air no longer optional
The gas-powered Valley Generating Station is seen in the San Fernando Valley on March 10, 2017 in Sun Valley, California. Atmospheric carbon dioxide levels reached a new record high in 2016 and have continued to climb in the first two months of 2017, scientists at the National Oceanic and Atmospheric Administration (NOAA) reported today. The vast majority of climate scientists contend that increasing greenhouse gas emissions drive climate change but new Environmental Protection Agency (EPA) Administrator Scott Pruitt disagrees.
David McNew/Getty Images/AFP

PARIS, France — The burning question going into the Glasgow climate summit is whether major economies can, by 2050, reduce emissions enough to deliver a carbon neutral world in which humanity no longer adds planet-warming gases to the atmosphere. 

Less talked about — but rising quickly on the climate agenda — are tools and techniques to pull CO2 straight out of the air.

Even scientists sceptical about its feasibility agree that without carbon dioxide removal (CDR) — aka "negative emission" — it will be extremely difficult to meet the Paris Agreement goal of capping global warming below two degrees Celsius.

"We need drastic, radical emissions reductions, and on top of that we need some CDR," said Glen Peters, research director at the Centre for International Climate Research. 

What is CO2 removal?

There are basically two ways to extract CO2 from thin air.  

One is to boost nature's capacity to absorb and stockpile carbon. Healing degraded forests, restoring mangroves, industrial-scale tree planNice, Franceting, boosting carbon uptake in rocks or the ocean — all fall under the hotly debated category of "nature-based solutions".

The second way — called direct air capture — uses chemical processes to strip out CO2, then recycles it for industrial use or locks it away in porous rock formations, unused coal beds or saline aquifers.   

A variation known as bioenergy with carbon capture and storage, or BECCS, combines elements from both approaches. 

Wood pellets or other biomass is converted into biofuels or burned to drive turbines that generate electricity. The CO2 emitted is roughly cancelled out by the CO2 absorbed during plant growth.

But when carbon dioxide in the power plant's exhaust is syphoned off and stored underground, the process becomes a net-negative technology.

Do we really need it?

Yes, for a couple of reasons.

Even if the world begins drawing down carbon pollution by three, four or five percent each year — and that is a very big "if" — some sectors like cement and steel production, long-haul aviation and agriculture are expected to maintain emission levels for decades. 

"We have modelling, but no one is sure what we might need in 2050," said Oliver Geden, a senior fellow at the German Institute for International and Security Affairs and an expert on CDR. 

"There will be residual emissions and the numbers might be high."

And there is another reason. 

The August report from the UN's Intergovernmental Panel on Climate Change (IPCC) makes it alarmingly clear that the 1.5C threshold will be breached in the coming decades no matter how aggressively greenhouse gases are drawn down. 

CO2 lingers in the atmosphere for centuries, which means that the only way to bring Earth's average surface temperature back under the wire by 2100 is to suck some of it out of the air.  

What's hot, what's not?

BECCS was pencilled into IPCC climate models more than a decade ago as the theoretically cheapest form of negative emissions, but has barely developed since.

The technology's prospects took a hit this week when Britain's large Drax Power Station, converted to run on biomass and store emitted CO2, was dropped from an investment listing of sustainable companies, the S&P Clean Energy Index.  

"I don't see a BECCS boom," said Geden.

A peer-reviewed proposal in 2019 to draw down excess CO2 by planting a trillion trees sparked huge excitement in the media and among gas and oil companies that have made afforestation offsets a central pillar of their attempts to align with Paris treaty goals.

But the idea was sharply criticised by experts, who pointed out that it would require converting twice the area of India into mono-culture tree farms.    

Also, planting trees to soak up CO2 is fine — until the forests burn down in climate-enhanced wildfires.

"They really have a problem in California," Geden said. "The state deals with forest offsets and emissions trading, but their forests are burning down."

Among all the carbon dioxide removal methods, direct air capture is among the least developed but the most talked about. 

"It's such a sexy technology," said Peters. "Part of that is marketing — glossy brochures, a fancy technology, shiny silver. It captures the imagination."

How fast can we scale up?

In reality direct air capture (DAC) is a large-scale industrial process that requires huge amounts of energy to run.

Existing technology is also a long way from making a dent in the problem.

For example, the amount of CO2 extracted in a year by the world's largest direct air capture plant (4,000 tons) — opened last month in Iceland by Climeworks — is equivalent to three seconds' worth of current global emissions (40 billion tons).

Earlier this year a team of researchers led by David Victor at the University of California San Diego's Deep Decarbonisation Initiative wanted to see how much a "wartime-like crash deployment" of DAC could lower CO2 concentrations under different emissions scenarios.

Assuming investment of a trillion dollars a year starting now, DAC knocked off some two billion tonnes of CO2 annually from global emissions by 2050 in the models. 

But only when coupled with the most ambitious carbon-cutting scenario laid out by the IPCC was that enough to bring temperatures back down — after rising to 2C — to around 1.7C by 2100.

Corporate investment?

Direct Air Capture has benefited from a wave of corporate backing.

In April, Tesla CEO Elon Musk launched the $100-million X-Prize for CO2 removal technology.

Last month, Breakthrough Energy founder Bill Gates unveiled a corporate partnership — American Airlines, ArcelorMittal, Bank of America, Microsoft, The BlackRock Foundation and General Motors — to turbocharge the development of direct air capture, sustainable aviation fuel and two other new energy technologies.

"A global carbon removal industry is coming," Johanna Forster and Naomi Vaughan, both from the University of East Anglia, noted last week in a commentary.  

The danger, said Peters, is that some companies may talk up future carbon dioxide removal rather than reducing emissions today.  

Impact on UN negotiations?

Appeals to remove the amount of CO2 in the atmosphere have begun to enter the political arena, and could become a contentious issue at the UN negotiations in Glasgow and beyond, experts say.

First India, then China, called earlier this year on rich countries to go beyond 2050 net-zero commitments. 

"Countries from the Global South are demanding that industrialised countries go net-negative," said Geden.

Small island states whose nations are literally slipping under the waves "are dead serious about carbon dioxide removal already," he added.

For David King, chair of the Climate Crisis Advisory Group, "net-zero by 2050 is no long enough."

"We must revise global targets beyond net zero and commit to net negative strategies," he said earlier this month.




As It Happens
LATEST UPDATE: July 3, 2022 - 9:39am

Follow this page for updates about climate change and information on current environmental issues. Main photo by Efigenio Toledo IV

July 3, 2022 - 9:39am

In the 15 years since Adam Dailey began boating on Lake Mead, the shoreline has receded hundreds of meters, the result of more than two decades of punishing drought that is drying out the western United States.

Launch spots that lined the edge of the lake, located outside Las Vegas, have been abandoned, and a single ramp is now the only way to get a boat in the water.

"We used to have more. So everyone's fighting to use one ramp... and still trying to figure out how to get along," said Dailey.

"It's kind of sad, what's going on. But we still come out and try to enjoy it when we can."

Lake Mead is the largest reservoir in the United States, a huge man-made body of water formed by the construction of the Hoover Dam in the early 1930s.

Its 640-square-kilometer surface area stores water for tens of millions of people and countless acres of farmland in the southwest.

But it's shrinking at a terrifying rate and now stands at just one-quarter full.

The National Park Service (NPS), which manages access to the lake, has spent more than $40 million since 2010 trying to keep the water open to boaters.

It costs them $2-3 million dollars to reconfigure the boat launch ramp every time the water levels fall another four feet (120 centimeters).

"Declining water levels due to climate change and 20 years of ongoing drought have reshaped the park’s shorelines," the NPS says on its website.  ?— AFP

July 1, 2022 - 2:16pm

India imposes a ban on many single-use plastics in a bid to tackle waste choking rivers and poisoning wildlife, but experts say it faces severe headwinds from unprepared manufacturers and consumers unwilling to pay more.

The country generates around four million tonnes of plastic waste per year, about a third of which is not recycled and ends up in waterways and landfills that regularly catch fire and exacerbate air pollution.

Stray cows munching on plastic are a common sight in Indian cities and a recent study found traces in the dung of elephants in the northern forests of Uttarakhand state. — AFP

June 22, 2022 - 2:51pm

Egypt hopes to jump-start the action needed to face a warming world when it takes the presidency of major UN climate talks in November, but warns that countries need a "reality check" as progress stalls. 

Presiding over the inflection point when a decades-long United Nations climate process switches from negotiation to "implementation", Egypt has set a high bar for its leadership of this year's COP27 climate summit.

But the challenge of maintaining international momentum on climate change has been made even harder as the world faces a catalogue of challenges, with Russia's invasion of Ukraine and spiralling food, energy and economic crises. 

"Because of the geopolitical situation, climate change is being pushed back," said Ambassador Mohamed Nasr at a meeting in the German city of Bonn meant to lay the groundwork for the Egyptian conference.

"We are facing a big challenge."  — AFP

June 18, 2022 - 4:40pm

The indigenous people in South Cotabato are not bothered by the veto by Gov. Reynaldo Tamayo of the provincial board’s lifting of a province-wide open-pit mining ban.

Tamayo on June 3 vetoed the measure, but emphasized clearly that any such local ban cannot stop large-scale mining operations in South Cotabato with permits from the national government.

For South Cotabato’s Blaan and T’boli communities wishing since the early 1990s to have the copper and coal deposits in their ancestral lands extracted, it was a strong “policy statement” from Tamayo. — The STAR/John Unson

June 16, 2022 - 10:41am

Australia's new center-left government submits new, more ambitious, emissions targets to the United Nations Thursday, seeking to end a decade of footdragging on climate change.

Prime Minister Anthony Albanese raises the country's 2030 emissions reduction target to 43%, saying it "sets Australia up for a prosperous future, a future powered by cleaner, cheaper energy".

Australia's existing commitment, made under the Paris Agreement, called for a more modest 26-28 percent cut on 2005 emissions levels. — AFP

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