This briefing summarises the main findings and recommendations of the IPCC’s 5th Assessment report, related to cities.

It outlines the major impacts of climate change facing cities and discusses how increasing migration to cities and urbanisation is exacerbating the risk of these impacts for the urban populations, systems and infrastructure. The author considers the concept of resilience and notes that steps which bring resilience and sustainable development goals together can lead to successful adaptation. The briefing details potential mitigation activities, including sectoral strategies and advancing to cross-sectoral strategies for longer-term mitigation and inclusive development potential.

This document is accompanied by an infographic which summarises the ways in which cities are on the front lines of a changing climate through their contribution to global climate change, and the urban impacts and mitigation efforts, as laid out in the IPCC’s report. Key findings include:

Many emerging climate change risks are concentrated in urban areas: Urban areas hold more than half the world’s population and most of its built assets and economic activities. 
Climate change impacts on cities are increasing: Key issues include rising temperatures, heat stress, water security and pollution, sea-level rise and storm surges, extreme weather events, among others.  
The world’s urban population is forecast almost to double by 2050, increasing the number of people and assets exposed to climate change risks: Rapid urbanisation in low- and middle- income countries has already increased the number of highly vulnerable urban communities living in informal settlements.
Steps that build resilience and enable sustainable development in urban areas can accelerate successful climate change adaptation globally: Adaptation options exist in areas such as water, food, energy and transport.
The greatest potential for mitigating greenhouse gas emissions may lie in rapidly developing cities in industrialising countries. Sectors with potential for mitigation include buildings, energy, transport, and industry. However, many rapidly developing cities lack the financial, technological, institutional and governance capacity required for effective mitigation.

This brief concludes that the next twenty years present a window of opportunity for cities to transform their relationship with climate change through long term strategising, greater political will, institutional capacity development and horizontal learning between cities.