Handful of cities driving greenhouse gas emissions

LONDON: Just 25 big cities accounted for more than half of the climate-warming gases pumped out by a sample of 167 urban hubs around the world, an analysis of emissions trends showed.

In per capita terms, however, emissions from cities in the richest parts of the world are still generally higher than those from urban centres in developing countries, researchers found in the study published in the Frontiers journal.

The study compared greenhouse gas emissions reported by 167 cities in 53 countries and found that 23 Chinese cities — among them Shanghai, Beijing and Handan — along with Moscow and Tokyo accounted for 52 per cent of the total.

It included more cities from China, India, the United States and the European Union because of their larger contribution to global emissions and significance to the climate debate. The findings highlighted the significant role cities play in reducing emissions, said study co-author Shaoqing Chen, an environmental scientist at Sun Yat-sen University in the southern Chinese city of Guangzhou.

“It is simple, logical,” he said. “If you don’t act, eventually you will suffer from (climate change),” he said.

Average global temperatures have already risen by more than 1 degrees Celsius compared to the preindustrial baseline and are still on track to exceed the 1.5-2 degrees limit set by the Paris Agreement. Chen and other scientists cautioned, however, that some of the data available for use in their study were patchy, with some cities reporting numbers from as far back as 2005. A lack of consistency in how cities report emissions also makes comparisons tricky, they added.