There’s another way to combat climate change — but let’s not call it geoengineering

Anita Talberg, University of Melbourne and Tim Flannery, University of Melbourne

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 CO₂ out of the air and sea at a faster rate than occurs presently, and how we might store the recovered CO₂ 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 CO₂ from the air; producing and using biochar; farming CO₂-absorbing seaweed; and constructing buildings from carbon-neutral cement capable of capturing CO₂ 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.

Anita Talberg is PhD student in the Australian German Climate and Energy College at University of Melbourne and Tim Flannery is Professorial fellow, Melbourne Sustainable Society Institute at University of Melbourne

This article was originally published on The Conversation. Read the original article.

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Cuba: Havana

Warming seas will set marine life on the move, with some good news among the bad

David Schoeman, University of the Sunshine Coast and Jorge García Molinos, Scottish Association for Marine Science

How will climate change affect life in the oceans? In research to be published in Nature Climate Change* we, among several other authors, show that the answer is likely good and bad.

Our study models how species might move in response to different future climate scenarios. The good news is that overall, thanks to species migrations, most places will end up with greater numbers of species. According to our models, climate change is unlikely to directly cause extinction through warming waters for most species, except for those that can’t move or have very narrow thermal tolerances.

The bad news is that there are a few very special places that will lose species – particularly the spectacular ocean ecosystems of what’s known as the Coral Triangle, the epicentre of global marine biodiversity.

First, the good news

As ocean temperatures increase, marine life will likely move towards the poles – animals and plants will expand their ranges. We can already see this happening. In Australia, tropical species of fish are turning up in northern New South Wales.

We wanted to know how this would affect the overall numbers of animals and plants in the oceans – marine biodiversity – and the distinctive communities they comprise. While many things affect where marine life lives – habitat, competition, salinity – most species are affected fundamentally by temperature.

Using temperature to find out where species might move allowed us to look at an unprecedented number of species – nearly 13,000. These included animals and plants as diverse as fish, corals, jellies, snails, clams, crabs, shrimps and seaweeds.

We looked at two different climate scenarios, business as usual (known as RCP8.5) leading to warming of around 2.5ºC by 2100, and a scenario with medium mitigation (RCP4.5) leading to warming of around 1ºC over the same period.

Our model shows how fast different temperature zones will move and to where, using a measure known as “climate velocity”. This is a good way of predicting where species could move because it traces pathways connected by climate.

We should emphasise that our study shows where species could move. Our projections don’t necessarily mean that they will move, nor that they will successfully establish themselves at the locations where they arrive. That depends on a variety of factors, including their specific habitat requirements and how species interact with each other. But studies of invasive species suggest that species that can move will tend to do so.

Overall we found that biodiversity of the oceans will likely increase at local scales. As a result, we anticipate that marine ecosystems will become more similar. For instance, today on the east Australian coast, the types of species found along the central Queensland coast are quite different from those found in central New South Wales. As sea temperatures warm, we expect those boundaries to gradually break down, leading to what we call a “smearing” of biodiversity.

Bad news for the tropics

There are several theories as to why there are so many species in the tropics, and especially the Coral Triangle. Irrespective, we know that this area supports over 500 species of reef-forming corals, together with a massive diversity of fish, including whale sharks, and six of the seven extant species of sea turtles; it is also visited by many species of whales and dolphins. This concentration of marine biodiversity contributes significantly to livelihoods of the region’s 120 million or so human inhabitants.

Species living in tropical seas already live close to their thermal optimum. As temperatures increase, they will exceed the upper thermal limits of some species. When this happens, some species will adapt, for instance by seeking out micro-refuges, such as small patches of cool water caused by upwelling, or they might resort to living in deeper waters, if the water is clear enough.

But in the long term, most species will need to move. The reason we expect marine biodiversity to decrease in the tropics with warming is that there is no place warmer to act as a source of new species to replace those species moving out.

More than 5,000 of the 13,000 species we looked at in our study are found in the coral triangle. According to our projections, approximately 500 to 1,000 of these species will leave the region thanks to warming waters under RCP4.5 and RCP8.5, respectively.

What can we do?

Our modelling shows that the loss of marine life is strongly related to how much we mitigate climate change.

Even if we take only intermediate levels of action (under scenario RCP4.5), we can minimise the damage. But we can’t eliminate it entirely: under the emission-stabilisation RCP4.5 scenario we anticipate that the Coral Triangle will lose roughly half as many species as under the business-as-usual RCP8.5 scenario.

We can also look at how we manage the world’s oceans. Some regions, such as the northeast Atlantic and eastern Mediterranean, have seen greater impacts from people than others, and some of these overlap with regions likely to be affected by climate change.

Where there is overlap, we can look at alleviating the damage caused by people, such as pollution of coastal waters, or minimising the pressure on key species, for example by reducing fishing pressure on them.

In other areas, such as the poles, there is low human impact, but we project substantial changes in biodiversity. From a conservation perspective, we want representative sections of these areas to remain free from additional human pressure, for instance by using regulation to control future development.

And because climate change doesn’t respect national boundaries, all of these efforts will require international cooperation.

Only in that way will we ensure the seas remain rich and healthy in the future.

We acknowledge the contributions of all co-authors: Jorge Garcia Molinos, Benjamin S. Halpern, David S. Schoeman, Christopher J. Brown, Wolfgang Kiessling, Pippa J. Moore, John M. Pandolfi, Elvira S. Poloczanska, Anthony J. Richardson and Michael T. Burrows

*Update August 25: the paper on which this article is based has not yet been published. The article will be updated when the link is available.

David Schoeman is Associate professor, Biostatistics at University of the Sunshine Coast and Jorge García Molinos is Research Associate Climate Change Ecology at Scottish Association for Marine Science

This article was originally published on The Conversation. Read the original article.