Cities are important centers of opportunity and drivers of prosperity, accounting for over 80% of global economic activity. Cities are also home to more than half of the world’s population, while suburbanization continues.
70% of the world’s population will live in cities by 2050. Increasingly, climate change is exposing cities to extreme weather events as well as stresses such as rising average temperatures, sea level rise, biodiversity loss and degradation of ecosystem.
At the same time, cities contribute to climate change by producing about 70% of global greenhouse gas emissions.
Cities must therefore play a dual role. First, they must act to mitigate the effects of climate change while adapting to better manage them.
To understand the extent to which an inclusion is more or less vulnerable to climate change, the World Bank examined 10,000 cities taking into account the following parameters.
Typology by size: small, medium and large cities and typology by income: cities in high-, middle- and low-income countries. Here are some results:
Cities in high- and middle-income countries are responsible for most of the emissions. Indeed, these high and middle income countries are responsible for 86% of global CO2 emissions.
Cities in low-income countries account for 14% of emissions, with the poorest of the low-income countries accounting for a negligible 0.2% of emissions.
Although high-income countries are responsible for the bulk of global emissions, it is cities in low-income countries that face the greatest impacts of climate change, as measured by an index that takes into account six elements: floods, heat, cyclones, sea level rise, water stress and wildfires.
Some of the reasons for this result are as follows:
Cities in low-income countries are less resilient, in part because of the challenges of providing basic services, affordable housing and safe places.
These cities still lack resilient infrastructure to cope with rapid population growth and inadequate planning.
Another challenge is the provision of quality public transport, which means that rapid urbanization often leads to low-density sprawl and traffic congestion.
To address the interrelated challenges of climate change and urbanization, policy makers at local and national levels need to work together to define sets of policy instruments that can be used technically. Some of these policy instruments will be discussed in the companion publication