Cities and Climate Change: Understanding the Link

Cities and climate change are intrinsically linked. Home to half the world’s population and growing rapidly, cities consume over two-thirds of the world’s energy and account for more than 70 percent of global CO2 emissions. At the same time, some of the greatest hazards of climate change, from rising sea levels to heat waves, threaten cities most directly.

As stewards of our cities, Mayors have a responsibility to confront climate change. And they are determined to do so. Acting both locally and collaboratively, today’s megacities are making a difference byimplementing sustainability practices that, in part, capitalize on urban densities to deliver low carbon infrastructure and systems. While each city is unique in its scope of control over municipal services, technical savvy and even progress in addressing climate change, the underlying emission sources are largely the same:  

  • Inefficiencies in building energy use
  • Carbon-intensive vehicles and traffic congestion
  • Solid waste landfills that release methane – a greenhouse gas agent 23 times more potent than CO2 – as garbage decays. 
  • Inefficiencies in street and traffic lighting. 

 Click here to view the “Why Cities” factsheet.