Why a Nature-Based Cooling Solutions Working Group?

In March 2022, the global community agreed on a common definition of Nature-based solutions (NbS) as “actions to protect, sustainably manage, and restore natural or modified ecosystems that effectively and adaptively address societal challenges, while providing human well-being and biodiversity benefits”. This UNEA resolution brings increased attention to the topic of NbS, their transformational potential to help tackle climate change, biodiversity loss, disaster risk reduction, food security, and human health.

NbS applied in urban environments can help address urgent and fundamental environmental challenges by bringing ecosystem services back into cities and rebalancing their relationship with surrounding areas. Nature can play a key role in increasing cities’ resilience against extreme heat. Trees, vegetation, water bodies, rooftop gardens, and green surfaces mitigate the Urban Heat Island Effect (UHIE) and improve thermal comfort in and around buildings, simultaneously reducing mechanical cooling demand and bringing social cohesion and higher quality of life and health to communities. This, while delivering economic and environmental benefits: urban trees in 10 of the world’s megacities generate $482 million per year in health cost savings as a result of pollutants reduction.

Despite their benefits, NbS implementation in cities is lagging due to a variety of barriers: lack of capacity to incorporate the planning of NbS in urban master planning and building design; knowledge gaps on the effectiveness of NbS in achieving local goals; limited availability of sustainable business models and financing mechanisms; lack of access to geospatial data tools and technical expertise to optimally introduce and preserve urban green and blue spaces; the short-term character of municipal initiatives compared to long-term investments and planning that NbS require. Solutions exist, but they need to be better understood and leveraged to bring about change at a global level.

This working group aims at drawing on Cool Coalition members’ expertise to build targeted knowledge, policy, financing support tools, and implementation support to help cities increase the adoption of NbS for thermal comfort. The WG’s main activities will consist in designing and rolling out a NbS for Cooling Cities Challenge, identifying and strengthening existing available tools to support cities in implementing NbS for cooling, mapping existing funding sources and effective business models, and developing targeted guidance for cities.


Highlights and Achievements in 2021-2022

  • Collected best practices and 20 case studies from cities around the world and support the development of Beating the Heat: A Sustainable Cooling Handbook for Cities, a guide to offer planners and policymakers an encyclopedia of NbS options to help cool cities. 
  • Launched the Handbook at a dedicated side event at COP26 in Glasgow, UK (November 2021) with an event co-hosted with UNEP, RMI, GCoM, Mission Innovation, and Clean Cooling Collaborative.
  • Organised Nature-Based Solutions for Cooling Cities webinar, as part of the World Bank series “Bringing Nature to Cities: Integrated Urban Solutions to Biodiversity Loss and Climate Change”. The event amplified UNEP and Cool Coalition’s focus on NbS for the 2022 international agenda to counter extreme heat in cities.
  • Convened a high-level session at the 2nd UNEA Cities and Regions Summit on Urban Nature-Based Solutions to Counter Climate Risks and Limit Global Warming. The event brought together Mayors, Ministers and leading global experts to showcase concrete examples of cooling benefits of nature and enabled a discussion on key levers to accelerate implementation of NbS in cities. The Summit’s outcomes provided a contribution to the UN Decade on Ecosystems Restoration and to the preparation of the Conference of the Parties to the Convention on Biological Diversity, set to take place in December 2022.


Priorities and Objectives for 2022 and 2023

  • Coordinate efforts to define and roll out Nature-based Urban Cooling Challenge: 
    • Support the design of dedicated challenge for cities on NbS for cooling initiated by SEforALL, including the definition of: challenge scope and criteria, pledge for participants and reward for winners, scoring and evaluation parameters for submissions
    • Conduct outreach to cities to ensure participation to the challenge
    • Act as technical evaluation committee for the challenge submissions and support reward assignment
    • Co-organize and contribute to events and outreach related to the challenge, including to announce challenge winners and disseminate best practices
  • Identify successful NbS for cooling financing, and develop guidance for cities to scale up investments:
    • Analyze how to scale-up successful business models to accelerate NbS deployment in urban areas, including by leveraging existing financial support systems and funds at a national and regional level.
    • Engage with DFIs and MDBs to identify how they can play a role in increasing NbS financing and de-risk investments.
    • Identify and disseminate tools to make the case for investment and action, including to predict urban NbS impact on energy and carbon savings and temperature reductions.
    • Develop compendium of existing data, funding sources, support tools that can support NbS for cooling implementation in cities.
  • Capacity building for governments, practitioners and financial institutions in different regions, including training staff working for cities and states through workshops and webinars, to increase capacity to act on NbS for cooling.
  • Support, when requested, governments in the implementation of NbS for cooling, prioritizing regions where action to counter extreme heat is most needed, building on cities’ experience and practice, and creating synergies and knowledge.



– Lead: Jennifer Lenhart, Global Lead, WWF Cities, jennifer.lenhart@wwf.se

– Facilitator: Irene Fagotto, Cool Coalition Secretariat, United Nations Environment Programme (UNEP), irene.fagotto@un.org