From pledges to action: Cities need to show their climate progress with hard data

As world leaders negotiate rules for cutting greenhouse gas emissions at the COP24 meeting in Poland, U.S. cities have a vested interest in the outcome. About 85 percent of Americans live in cities, and urban areas produce some 80 percent of our nation’s greenhouse gas emissions. Many cities are highly vulnerable to climate change impacts such as flooding and heat waves.

Cities are central to shaping effective solutions, too. After President Donald Trump announced in 2017 that he planned to withdraw the United States from the Paris climate accord, more than 400 U.S. mayors – representing 69 million people – pledged to fulfill it. Some cities are going further and aiming for net carbon neutrality by 2050. Their efforts are sorely needed: According to a Dec. 5 report from the Global Carbon Project, global carbon dioxide emissions grew 2.7 percent in 2018, the largest rise in seven years.

Mayors believe they can make a climate impact while making their communities greener and cleaner. To succeed, they will have to take bold policy actions and demonstrate that emissions are declining. However, tracking greenhouse gas emissions requires models, forecasting tools and lots of data. Today most of that information is organized at the national or state level, not at city scales.