Executive Summary

Over the last two decades, a staggering 750 million South Asians, representing over half of the region’s population, have experienced the impacts of various natural disasters such as floods, droughts, and cyclones. Projections indicate that if current patterns persist, the Global South is poised to incur an average annual loss of USD 160 billion by 2030 due to climate impacts, implying that this region, in particular, is disproportionately vulnerable to the effects of climate change (World Bank 2022). Therefore, it is crucial to develop effective strategies to enhance resilience and mitigate the impacts. An effective approach to mitigating climate impacts in the developing world is deploying nature-based solutions (NbS). NbS encompass a broad range of strategies that utilise natural processes and ecosystems to reduce flooding, sequester carbon, preserve biodiversity, and enhance living standards by providing fresh air, clean water amongst others. NbS have the potential to cost-effectively achieve around 30 per cent of the mitigation needed by 2030 to stabilise the global temperature increase to below 2°C (IUCN 2019).

Although the benefits of NbS are recognised globally, their financing and implementation often fall short of proposed targets. The global market for NbS is valued at between USD 125 and USD 300 billion annually (WEF 2020), but it receives only about USD 200 billion in investments per year, with the private sector contributing merely 18 per cent. Further, high-income countries, such as those in North America and Europe, receive the lion’s share of NbS investments, accounting for approximately 75 per cent of the total (UNEP 2022).

In contrast, low-income countries receive only a small fraction of NbS investments, despite being more vulnerable to the impacts of climate change. The absence of standardised measures and reporting on the impacts of NbS make it difficult to evaluate their effectiveness and, consequently, hinder investments in this sector and the scaling up of successful projects. A lack of expertise and methodologies for mapping benefits further discourages investments in NbS in the Global South. Thus, the need of the hour is a common assessment framework that can help stakeholders evaluate the economic and non-economic benefits of NbS.

This report provides a comprehensive understanding of NbS, details the difficulties associated with scaling and implementing such solutions, and proposes a framework to map and estimate the benefits of NbS in the Global South. This framework will allow users to:

a) identify an intervention as an NbS,

b) demarcate its benefits, and

c) estimate the cost-to-benefit ratio by providing a standardised approach to assess and report on their outcomes and costs.

Conducting due diligence before implementing NbS projects will help drive investments in the sector, allow stakeholders to scale up such interventions, and maximise impact in the long run.

Figure ES1 The benefits of investing in nature-based solutions