Bold policies needed to tackle unsustainable urban growth, climate change

Globally, 70% of greenhouse gas (GHG) emissions emanate from cities. At the same time, cities are being hit increasingly by climate change-related shocks and stresses, ranging from more frequent extreme weather events to inflows of climate migrants.
In the last 50 years or so, the number of people living in cities has almost quadrupled and the earth’s surface temperature climbed by nearly 1.2C above its preindustrial levels, according to the World Bank.
This warming has been associated with an increased frequency of extreme hot, dry, and wet events across cities worldwide. Global sea-level rise has also increased the risk of flooding for many coastal cities.
Because of the prosperity they have helped generate, cities have been an important cause of this climate change, the World Bank noted. At the same time, this prosperity has helped make cities more resilient to climate change–related shocks and stressors.
Cities have also become increasingly vocal advocates of climate action; however, in the race between climate change and climate action, climate change retains a commanding lead.
Cities in high and upper middle income countries, which account for the bulk of global urban carbon dioxide (CO2) emissions, are not moving quickly enough towards net zero. Similarly, although their current contributions to climate change may be small, cities in lower-income countries are not acting fast enough to moderate their emissions trajectories.
These trajectories, if left unchecked, will eventually offset any reductions in global emissions made by cities in higher-income countries.
Poorly managed urbanisation also contributes to an even larger problem — the more general erosion of natural capital. This erosion takes the form not only of polluted skies but also of contaminated water bodies, destroyed natural habitats, and the loss of both plant and animal species.
In addition to not acting quickly enough to mitigate climate change, cities, especially those in low- and lower-middle-income countries, are also not adapting quickly enough to its challenges.
The residents of cities in lower and even in higher income countries may see climate change as a secondary concern, especially when pitted against poverty, inequality, and a lack of access to markets and services — problems that for some people and some cities have worsened over time, the World Bank noted.
Global GHG emissions will remain above the level required to limit global warming to 1.5C if low and lower middle income countries continue to follow their current policies.
To ensure that cities thrive in a world confronted by climate change, policy makers at both national and local levels need to work together to implement bold policies to address the interrelated stresses that arise from climate change and urban growth.
These include the stresses arising from the pressure of a city’s population on its supplies of land, housing, and basic services; its stock of infrastructure; and its environment.
If not well managed, the World Bank warns such stresses can give rise to slums, deteriorating levels and quality of basic service provision, streets gridlocked with polluting cars and motorcycles, excessive conversion of fertile agricultural land to urban uses, choking air pollution, and heightened greenhouse gas emissions.