Effects of urbanization on CO₂ emissions, water use and the carbon-water coupling in a typical dual-core urban agglomeration in China

Cities are the main carbon emitters and water consumers, therefore the development of cities is closely relative to carbon-water coupling, but the changes of this relationship during the urbanization is unclear. As a typical emerging dual-core urban agglomeration, carbon-water coupling during the urbanization process in Chengdu-Chongqing urban agglomeration (CCUA) is beneficial for achieving the goal of carbon peaking by 2030 and carbon neutralization by 2060 committed by the Chinese Government. Results showed that economic growth mainly promoted the increase of carbon emissions and water use while the intensity effect mainly restrained their growth. Meanwhile, the decoupling between CO₂ emissions and economy was increasing while the coupling between water use and economy was strengthened. These relationships promoted CCUA to enter a low-carbon development period after 2011, but the growth of water use has not been effectively suppressed. This indicated that CCUA has partly achieved the low carbon target but water-saving strategies should be paid more attention.