Does Nature Play A Role In Climate Change

The idea that "nature-based solutions" (NbS) can simultaneously address both the climate and biodiversity crises is a very attractive one; rich in win-win-win scenarios.

So much so that NbS – it has inevitably generated an acronym – has become a dominant narrative of environmental discourse. NbS is a driver behind the UN's decision to declare this the Decade on Ecosystem Restoration, and behind massive international afforestation programmes such equally the Bonn Challenge.

More locally, you've probably heard stories like this one, near the multiple ecosystem services that tin come back into play when ecological restoration is done on a sound scientific and social basis.

If nosotros restore a bog by rewetting it, nature will bring back threatened native plants and animals; it volition improve water quality and reduce flood damage; it will end carbon emissions from the degraded peat, and (perchance, eventually) draw down carbon from the atmosphere; and this project tin have demonstrable benefits for the physical and mental health of local communities, and attract tourist business.

And that can all exist true, in specific cases. A remarkable Irish example, the Abbeyleix Bog Projection, to give just 1 example, has already ticked most of these boxes in less than 20 years' exemplary restoration piece of work.

There is certainly something comforting in the notion that nature can heal the wounds our civilization has inflicted on our planetary life-support organisation. Just experts in this field advise that nosotros should be aware of letting warm and fuzzy feelings replace scientific analysis of very catchy problems.

Restoration ecology, and ecological applied science, accept certainly avant-garde much faster equally sciences than anyone expected 20 years agone, merely their best literature recognises that each project faces oft unpredictable challenges, and that climate change is quickly making restoration more difficult.

Climate specialists stress that we should be peculiarly wary of exaggerated claims by vested interests for the benefits of NbS in mitigating climate modify.

Two recent papers warn that we demand to be rigorous in measuring the effectiveness of NbS, and in assessing their appropriateness in different ecological and social settings. They besides call out corruption of the concept as a dodge to avoid painful merely necessary action in cut industrial and agricultural greenhouse gas emissions.

Writing in Ecosystem Services this yr, Cian White, Marcus Collier and Jane Stout, all of Trinity College Dublin, agree that "in practice, afforestation will be one of a portfolio of deportment to address climatic change". But they continue: "Due to land use and socio-economic constraints, tree planting could realistically result in global almanac sequestration rates of one gigatonne of carbon, a pregnant however small proportion of the greater than 50 gigatonnes of annual emissions."

Embryonic sphagnum-dominated vegetation developing on a Bord na Móna cutaway bog in the midlands. Sphagnum-rich vegetation acts a carbon store. Photograph: Bord na Móna — Embryonic sphagnum-dominated vegetation developing on a Bord na Móna cutaway bog in the midlands. Sphagnum-rich vegetation acts a carbon shop. Photograph: Bord na Móna

Ancommodity final year past led by Franziska Tanneberger of the highly regarded Greifswald Mire Centre in Advanced Sustainable Systems, to which Niall Ó Brolcháin of NUIG contributed, gives an upbeat assessment of the climate and other benefits of peatland restoration in the Eu. Again, all the same, the authors bespeak to the limits equally well as the strengths of NbS as a climate strategy: "They play a vitally of import role to mitigate and adapt to climatic change, but are non a substitute for a rapid fossil fuel phase-out and must not delay urgent activity to decarbonise our economies."

White's paper points out ii glaring but disquisitional gaps in the NbS literature to date: no-one had hitherto clearly defined what we hateful past "nature-based"; meanwhile, nosotros oft talk about "solutions" without defining the precise nature of the problem to be solved.

They argue that two criteria are needed for a project to authorize as an NbS: "A solution to a well-divers trouble is accomplished; and [that] ecosystem services brand the largest contribution to the solution."

This leads them to a detailed assay of claims virtually the benefits of NbS projects, from planting urban trees to constructing wetlands. To be admittedly clear, they fully recognise that these measures are frequently very benign. Indeed, Jane Stout is one of the creators of the All-Republic of ireland Pollinator Plan, which very successfully promotes mostly small actions by local communities to boost biodiversity.

But the authors insist that, if we are going to build NbS into major climate and biodiversity strategies, we must learn to be much more than precise well-nigh quantifying their impacts on problem-solving, in comparing to the impacts of traditional – and innovative – technological strategies. We must too be careful not to assume that an NbS that is effective on a small local scale can automatically exist scaled up regionally, much less globally.

Cian White told The Irish Times why they had adopted this stance: "I think the literature is over-enthusiastic most NbS potential and so was looking for NbS that have a sound evidence base of operations."

It'due south certainly increasingly evident that NbS demand to be submitted to the same scrutiny as technological measures, and climate downsides, equally well as upsides, highlighted. Rewetting bogs, for case, more often than not releases methyl hydride, a very powerful greenhouse gas, as well every bit reducing carbon emissions, though the rest is usually climate-positive, as the Tanneberger paper demonstrates. Others bespeak out that curt-rotation forestry schemes tin release much more carbon than they always sequester.

White says the development of accurate natural uppercase accounting is vital to revealing the bottom line of every climate mitigation proposal, and he believes that NbS tin play only a pocket-sized, though however of import, role in this battle, relative to technological solutions.

"If we were to halt deforestation, accounting for one gigatonne of emissions in 2016, and include the reasonable afforestment target of i gigatonne, forestry could mitigate roughly 4 per cent of 2016 emissions. To put that in context, energy accounts for some 75 per cent of emissions, so scaling the clean energy technologies nosotros have (solar, wind, nuclear, hydro, hydrogen) is essential."

This is perhaps not a message that many environmentalists desire to hear, but it surely deserves a hearing.

He also draws attention to the use of NbS in greenwashing by big corporations.

"There is a lot of international money in the carbon offsetting marketplace, where the language of NbS has recently been adopted for forestry and land use offsets.

"We need traceability and independent verification. Carbon offsets are legitimate when emissions cutting is not possible and could be useful for generating funding for nature-related projects. Unfortunately, the unregulated offsets are very cheap. And so Beat out can afford to buy offsets to sell 'carbon neutral' fossil fuels. This is a nature-based solution for Shell'due south business model, but non for climate change."

Console

Curt-term removals versus long-term solutions

John Sweeney, professor emeritus at Maynooth Academy and correspondent to the Intergovernmental Panel on Climate Change reports, also insists on the need for forensic examination of the numerous NbS proposals at the upcoming Cop26 coming together in Glasgow. He puts this in the context of recent claims by the Irish Farmers' Association, in its partially successful efforts to amend the Climate Beak, that carbon already sequestered in Irish landscapes should exist credited against current emissions from agronomics.

"My big affair has e'er been the language, y'all need to exist careful here. We need to place the difference between brusk-term carbon removals and long-term solutions.

"Farmers talk almost 'removal' of carbon by hedgerows and so on, just this shifts into an argument for carbon credits for rye grass that is only in the process of existence eaten and then re-emitted as marsh gas.

"And soil carbon storage will take decades or centuries to make a deviation, but it'southward being shoved on to accounts as a big 'origin green' benefit.

"There is a place for forestry in global climate strategy, but in Ireland it's non a nature-based solution. When you plough up land for forestry you create a net carbon source, but no one seems to exist corking to recognise that kickoff.

"In that location are rules in the IPCC every bit to what can be counted as carbon sequestration, and I've badgered the Authorities to apply them here, but I've no religion in their backbone, they won't stand up against the IFA."

"We are jumping into alternative energy schemes without doing a full climate price/benefit analysis."

The benefits of NbS projects tin undoubtedly often exist remarkable, especially for biodiversity, and inspire deep community engagement in environmental issues. But overstating their impact in the climate arena, where they are non a global gamechanger, volition just ignominy them in public opinion when they fail. NbS advocates exercise all-time when they under-promise, and over-deliver.

Paddy Woodworth is writer of Our One time and Future Planet: Restoring the World in the Climate change Century (Chicago 2013), and vice-chair of the steering commission of Natural Capital Ireland