Nature-Based Solutions: an overlooked answer to climate change

As part of my COPCAS experience, I had the pleasure of interviewing Danilo Ignacio de Urzedo, a PhD candidate at the University of Sydney and delegate at COP25 for Youth4Nature, an organisation dedicated to empowering young people to advocate for Nature-Based Solutions to climate change.

At the time I was unfamiliar with the term ‘Nature-Based Solutions’ (or NBS for short) – which can be used to reduce greenhouse gas emissions – however by contrast I’ve heard about plenty of renewable energy technologies and ‘carbon capture and storage’ methods. It turns out my ignorance may reflect the lack of discussion and publicity around NBS: ‘most of the debates focus on technology, infrastructure, energy, renewables; and then forests, stopping deforestation, restoring degraded lands - have been overlooked’ explained Danilo. It was Danilo’s next point which really surprised me: ‘Nature-Based Solutions are getting only 3% of the investments, but we know that these kinds of strategies could support one third of solutions [for reduction of greenhouse gas emissions]’. So, why hadn’t I heard about NBS when it has such potential? And why is discussion and funding of NBS so little?

So what are Nature-Based Solutions?

In their simplest form, NBS are probably not all that unfamiliar to most people. Trees, which absorb atmospheric carbon dioxide (CO2) and store it in their tissue, act as ‘carbon sinks’. Carbon sinks remove carbon (in the form of CO2) from the atmosphere and store it elsewhere – in this case in trees. So, an easy to understand example of NBS is planting more trees, since this reduces our net greenhouse gas emissions and therefore mitigates climate change. Indeed, the core principle of many examples of NBS is simply storing carbon in various ecosystems through various methods.

There’s more to NBS than just planting trees though. There are plenty of ecosystems other than forests which can store carbon: wetlands and peatlands, grasslands, and coastal ecosystems such as mangroves, are all examples. And there are different ways to reduce net greenhouse gas emissions via these ecosystems: protection of existing areas, for example protecting rainforest against logging operations; regeneration of lost areas of ecosystems, such as through reforestation initiatives; and adjusting existing practices, particularly in agriculture, such as though planting of trees in farmland and adjusting rice cultivation practices to reduce emissions.

Furthermore, NBS aren’t only relevant to climate change mitigation efforts. Nature has been used to tackle other challenges, such as by protecting and restoring mangroves and marshes to act as barriers against flooding, or Mexico City’s ‘Via Verde’ – planting ‘vertical gardens’ along motorways to reduce air pollution.

The potential of Nature-Based Solutions

Focusing on mitigating climate change, the considerable potential of NBS was highlighted in a study by Dr. Bronson Griscom and other authors representing 19 different institutions, published in the journal Proceedings of the National Academy of Sciences in 2017. In this study the authors attempted to quantify the amount of CO2e emissions (where the subscript ‘e’ refers to ‘equivalent’ and incorporates emissions of other greenhouse gases) that could be reduced through NBS. They discounted any measures that would involve reduction of existing cropland, would cause loss of biodiversity, or would cause more warming than cooling due to effects other than greenhouse gas emissions.

Their total estimate came to 23.8 gigatonnes of CO2e per year, of which 11.3 gigatonnes CO2e per year would cost less than estimates of the social cost of climate change. They estimate that 11.3 gigatonnes is about one third of the reduction in CO2e yearly emissions required by 2030, compared with ‘business-as-usual’ emissions, if we want to keep global warming this century to less than 2 °C. However, this is only to have a >66% chance of keeping warming to below 2 °C. Furthermore, this estimate requires no increase in emissions from fossil fuels between 2017 and 2027, and decreasing fossil fuel emissions from 2027 to 2050, if we are to have that >66% chance. Consequently, by 2050, the relative contribution from NBS to emission reductions will be lower, because we will have needed further emission reductions from fossil fuels by then. Reductions in fossil fuel emissions are still very necessary then, even with NBS utilised to its maximum potential. Nonetheless, NBS can provide a considerable proportion of emissions reductions and the authors note it is more affordable than some developing carbon capture technologies.

Many of the solutions offering climate change mitigation by emission reduction offer co-benefits too, such as protecting biodiversity, improving food security and improving resilience to climate change. For example, the ‘Global Blue Carbon 10-Year Initiative’ led by China’s Ministry of Natural resources, aims to protect and restore coastal ecosystems such as mangroves, which will help store carbon, reduce the effects of sea level rise (e.g. flooding) and protect biodiversity.

So what’s the problem?

Perhaps the biggest challenge to greater implementation of NBS is a lack of funding, as pointed out by Danilo. A report by the Climate Policy Initiative in 2015 found that of the total global public finance spent on climate change mitigation ($119 billion), renewable energy received $49 billion (and several times more from private investments); while agriculture, forestry and land-use climate change mitigation received only $3 billion – so less than 3% of the total spent. This might be due to a tendency to want to sustain our current lifestyles – replacing fossil fuel generated electricity with that from renewable sources – while the importance of ecological sustainability is neglected.

Another challenge is lack of representation in government policy. The International Union for Conservation of Nature (IUCN) reviewed 10 previous investigations of how well NBS was represented in Nationally Determined Contributions (NDCs). NDCs are the emissions reductions that governments commit to as targets and the IUCN review covers NDCs of more than 160 countries. Their findings were that most countries’ NDCs do include examples of NBS, but that few had targets which were measurable or quantified, and the focus was mainly on forests – neglecting grasslands, peatlands and coastal ecosystems. Furthermore, the NDCs of high-income countries, as defined by the world bank, typically had less inclusion of NBS than low-income countries. This perhaps betrays the cost of alternative technological solutions, which are more expensive, making them harder for low-income countries to invest in, which look to NBS for solutions instead.

The IUCN report also noted the need for enhanced and robust financial support for NDCs. While this perhaps isn’t surprising, it did raise a concern in my mind: will this funding come from carbon trading schemes? NBS are often the means by which carbon can be offset, such as through tree planting in other countries, but there are potential problems with such schemes as discussed by my colleague James Fallon in his COPCAS 25 blog post. Indeed, during our interview Danilo expressed concern that although NBS was well-represented in side events at COP25, many of the discussions around NBS were fairly ‘mainstream’ and risked NBS initiatives being marketized. To be effective Danilo argued, NBS initiatives should be developed with indigenous peoples and local communities, taking into consideration co-benefits for people and the environment beyond just counting carbon and not just governed by markets. So, while more funding is needed for NBS, care needs to be taken over how the funding affects implementation of initiatives.

Future outlook

Recently there has been a growing awareness and support for NBS in climate mitigation discussions. A Nature-Based Solution Coalition co-led by China and New Zealand has been established which, in advance of the UN Climate Action Summit in September 2019, released a Nature-Based Solutions for Climate manifesto. The manifesto details the potential of NBS solutions for climate change mitigation and adaptation and calls for greater inclusion of NBS in government policies such as NDCs. The coalition also called for contributions of example NBS initiatives, receiving over 190 contributions, including the aforementioned Global Blue Carbon 10-Year initiative.

There were also a number of side events at COP25 dedicated to NBS, with nine side events including ‘Nature-Based’ in their titles and others including ‘coastal blue carbon’ or ‘forest-based solution’. In addition to this, a high-level event including representatives from several United Nations organisations dedicated to discussion of NBS was organised, within which inclusion of NBS into NDCs was encouraged. And of course, there are individuals and organisations such as Danilo and Youth4Nature that are advocating for NBS and scrutinising the debates to promote a people and environment-centred approach towards the implementation of NBS.

Hopefully the discussions about NBS and calls for the inclusion of NBS in policy will lead to its potential being realised. The coming year will be an important test: 2020 is the year the Paris Agreement requires countries to update their NDCs by. So, at the next COP – COP26 in Glasgow – we shall see whether the efforts to advocate NBS have been successfully translated into government policies. And beyond policy, how quickly will we see these solutions actually acted upon?