Written By Amrita Goldar and Tarun Singh
Five years after the adoption of the Paris Agreement, the signatories are again in the process of revising their nationally determined contributions as they prepare for COP26 that is scheduled for later this year. In its essence, the Paris Agreement recognises the importance of natural resources in climate change mitigation and adaptation strategies (Article 5.2) and further promotes the idea of building resilience of socioeconomic and ecological systems through economic diversification and sustainable management of natural resources (Article 7). Therefore, Nature based solutions (or NbS) that help with this resilience building and resource management were a major focus of the COP 25 meeting held in Madrid. Now, with the extended recognition from international groups like G7, G20 and along with the beginning of the United Nations Decade of Ecosystem Restoration in 2021, an even wider scale of discussions of NbS for climate change adaptation strategy at COP26 is envisaged.
Climate change presents one of the greatest challenges to mankind today. While thought of in separate contexts, both cities and natural ecosystems have the most to lose as far as climate change impacts are concerned. The vulnerability of cities in particular is further aggravated by added complexities of land use change, density of population, increased concretisation, social inequalities, poor air quality and several other associated issues. This poses a serious challenge to human health, social well-being, and quality of life, especially for the underprivileged classes of the society. Natural ecosystem losses such loss of biodiversity, depletion of water resources, etc. have similarly been well documented.
To overcome or minimise the impacts of climate change, there has been an emphasis on effective mitigation and adaptation strategies. While mitigation strategies can help in absorbing the atmospheric carbon dioxide and locking it away from the atmosphere, it can often be a time-taking process. In recent years, the idea of local-led adaptation has been widely discussed. Local-led adaptation refers to local communities, local governments acting strong in taking effective decisions to tackle climate change.
Local-led adaptation is often characterised by indigenous solutions, which are often associated with nature. Given that the most vulnerable populations are the ones that are more dependent on natural resources, it is therefore to be expected that coping solutions also often germinate from the same source. This directs us to NbS.
As a term, NbS is relatively new, but the concept has been practised for decades. The idea of protecting an ecosystem by restoring it is nothing but an example of Nbs. The International Union for Conservation of Nature (IUCN) defines NbS as actions to protect, sustainably manage and restore natural and modified ecosystems that address societal challenges effectively and adaptively, while simultaneously providing human well-being and biodiversity benefits. It is further associated with other sector specific terms like green infrastructure, natural infrastructure, ecological engineering, ecosystem-based mitigation, ecosystem-based adaptation, and ecosystem-based disaster risk reduction. While our understanding of NbS is still in the embryonic stage, we must understand that implementing NbS based projects doesn’t solely refer to planting trees; instead it involves a wider scope. To minimise the implementation gap, IUCN released a global standard including a set of criteria (8) and associated indicators (28) for addressing sustainable development goals and resilient project management.
To illustrate these criteria for decision-making prior to implementation, we take the example of restoration of a hilly area using NbS. This area once mined excessively for mineral resources; is now susceptible to soil erosion, landslides and increased climate risk. Restoring of such an area would address more than one societal challenge and would thus qualify for the first criterion. To meet the second criterion, the scale of the design of the restoration programme needs to be estimated. Further, whether or not the planned restoration will improve biodiversity of the region (third), and is economically workable (fourth) needs to be checked as well. For inclusive governance, the plantation of plant species must be carried out in consultation with local stakeholders as they are the ultimate caretakers of the plantation (fifth).
While we’re restoring the area, it might cause an improvement in the region’s biodiversity, it may also result in loss of playground for children (sixth). However, such trade-offs must be thought of in advance, mutually agreed upon and maintained throughout the time. To meet the seventh criterion, the restored area must be maintained, studied and effectively documented to support future decision making. The eight criteria of global NbS standards highlight the importance of replicating workable solutions in similar environments.
NbS have been very successful in helping local people to deal with impacts of climate change, improving ecosystem services and storing carbon. There exists several examples of these solutions working in tandem with nature, such as the restoration in the Lake District National Park, United Kingdom to achieve joint aims of enhancing biodiversity, improving water quality, encouraging natural regeneration of Woodstock, reducing soil erosion and several others. The project was successful in improving not just the local biodiversity, but also brought with it revenue generation by way of increased tourism.
In addition to NbS being used for restoring ecosystems, it can also be used in combination with man-made infrastructure in cities to benefit human health and urban biodiversity. As an adaptation strategy to urban heat island, NbS was used for cooling in the city of Madison, Wisconsin. The project showed a decrease in daytime temperature with increasing tree cover. The study further highlighted that a canopy cover of 40 per cent resulted in substantially cooler temperatures.
However, after these paragraphs extolling the benefits of NbS, a word of caution is needed. NbS are highly context specific, and their effectiveness is also uncertain under changing climatic conditions. While natural ecosystems are affected by changing climate, their effectiveness in future climate scenarios is questionable. Apart from the uncertainties revolving around the NbS, securing a continuous flow of investments is an added challenge. According to a report by United Nations Environment Programme (2020), an investment of $140 billion to $300 billion annually by 2030, rising to between $280 billion and $500 billion by 2050 might be required to finance NbS globally.
If we can address the complexities revolving around NbS along with securing sustainable investment, we might develop a climate resilient future in addition to protecting, conserving and restoring our natural environment.
Goldar is senior fellow and Singh is research assistant at the Climate Change and Sustainable Development Team, ICRIER