No matter how much we reduce greenhouse gas emissions, it will not be enough to keep global warming below 2C – the internationally agreed “safe” limit. This fact has been implied by the Intergovernmental Panel on Climate Change, and confirmed again recently by international research.

Does this mean we should give up? Not at all. There is a plan B to keep warming below dangerous levels: helping the planet to take more carbon dioxide out of the atmosphere.

In his new book Atmosphere of Hope, Tim Flannery, Climate Councillor and Professorial Fellow at the Melbourne Sustainable Society Institute (and co-author of this article), argues that these strategies will be necessary to combat climate change, but cannot substitute completely for reducing emissions.

Plan B

When the term “plan B” is mentioned in relation to climate change, ideas immediately turn to the presumed “techno-fix” of geoengineering.

Geoengineering, or “climate engineering” as it is also known, is a broad, all-encompassing definition that includes both managing solar radiation and removing carbon dioxide from the atmosphere.

Solar radiation management techniques are those that change the balance of the sun’s energy reaching the earth, versus the amount being reflected out. Like deploying a parasol, this aims to cool the planet without adjusting greenhouse gas levels.

In contrast, carbon dioxide removal methods “suck” carbon dioxide from the atmosphere to store it semi-permanently either underground, in rocks, or in animals, plants and ecosystems.

Often the distinctions between these two methods (and their potential impacts and different governance challenges) are not made clear. It is not uncommon for the term “geoengineering” to be used only to refer to managing the sun’s radiation reaching the Earth. This is presumably why at the first international conference on climate engineering in 2014 the chair Mark Lawrence called on all delegates to be discerning and precise in their use of language.

Talk of geoengineering tends to elicit uncomfortable feelings. This is in part because it has no obvious governance – how do you decide who takes action that will affect the whole world?

It is also because many of the techniques under the geoengineering umbrella have potentially serious adverse side-effects, both environmental and social (like a cure that could be worse than the disease). It is also largely because it feels wrong, conceptually, to try to address a problem caused by the dominance of Man over Nature through the further dominance of Man over Nature.

The third way

If emissions reduction is not enough and geoengineering ideas are decried as “ludicrous Bond-villain style schemes”, there must be another way … and there is.

According to research from the Tyndall Centre for Climate Change Research, geoengineering methods that are perceived as “natural” are more likely to receive public support.

What this suggests is that humanity would be more accepting of new proposals to deal with climate change if they worked alongside natural processes. “Natural” options would be ones that strengthened and supported the environment in doing what it already does: processing excess atmospheric carbon dioxide. This is the third way to deal with climate change.

The analogy has been drawn to a person battling weight gain. Reducing calorie intake is important but this should be supplemented by exercise to help the body do what it already does: burn excess fat. This analogy also likens some geoengineering techniques to lap-band surgery.

The third way is thus a concept that is described in Atmosphere of Hope as:

encompassing proposals and experiments that shed light on how Earth’s natural system for maintaining the carbon balance might be stimulated to draw CO 2 out of the air and sea at a faster rate than occurs presently, and how we might store the recovered CO 2 safely.

In essence, the division between the third way and geoengineering is a functional one.

Third-way ideas are extremely varied. They include planting trees or building artificial trees that capture CO 2 from the air; producing and using biochar; farming CO 2 -absorbing seaweed; and constructing buildings from carbon-neutral cement capable of capturing CO 2 from the air.

Determining whether a particular idea aligns with the third-way concept needs to be done on a case-by-case basis.

Ocean fertilisation is a good example. It involves adding elements or compounds (such as iron, nitrogen, phosphate, silica, or urea) to the oceans in an area that is nutrient deficient. This stimulates biological growth that can absorb carbon through photosynthesis.

Although the concept builds on existing natural processes, the outcome is uncertain and research suggests that there are environmental risks such as damaging fisheries and marine biodiversity (see here, here and here), causing localised warming, altering cloud formations and maybe even increasing greenhouse gas emissions.

Given the current state of research, ocean fertilisation does not look feasible or appropriate and thus may not qualify as third-way (despite sitting squarely under the geoengineering umbrella).

Direct Action could do the job

The third way may be easier for us to grapple with that geoengineering. This is perhaps because the third-way concept is already partially embedded in the Australian government’s approach to climate policy.

The government’s Direct Action mechanism is aimed at providing incentives for tackling rising atmospheric greenhouse gases. The Minister for the Environment has called Direct Action “source blind as to the type of abatement”. That means that the policy instrument does not discriminate on the technology or the sector within which the abatement takes place.

Direct Action also does not discriminate between emissions reduction and emissions removal (despite being financed by a government purse known as the Emissions Reduction Fund). In fact, the long title of the legislation is “An Act about projects to remove carbon dioxide from the atmosphere and projects to avoid emissions of greenhouse gases, and for other purposes”.

Of the 30 or so methods currently available for funding under the Emissions Reduction Fund only a small handful could be classified as third-way. And at this stage they are all within the agriculture and forestry sector.

This is because the legislation for Direct Action is inherited from the previous government’s Carbon Farming Initiative that focused exclusively on the land sector. However, technically (if not economically) there is the potential for third-way methods to gain more importance under Direct Action.

The third-way cannot be the only way

What should not be ignored, however, is the fact that the total capacity for third-way methods to help meet the climate change challenge is limited by a number of factors, including by nature itself, but also the pace of innovation and funding.

In Atmosphere of Hope, it is estimated that by mid-century up to about 40% of current global emissions could potentially be absorbed in this way.

Globally emissions from the burning fossil fuels and from cement production continue to increase.

In Australia, emissions from the combustion of fossil fuels levelled off in 2009, and even started to decrease (from reduced electricity demand) but have started to increase again in the latest financial year. The third way can only be a supplement to serious emissions reduction in Australia and worldwide, it should not be seen as a substitute.

The launch of Tim Flannery’s latest book, Atmosphere of Hope: Searching for Solutions to the Climate Crisis, will be hosted by the Melbourne Sustainable Society Institute on Wednesday 26 August. Tickets are available here.