Integrated Evaluation of City-Level CO2 Emissions and Sinks from 2010 to 2019: Spatio-temporal Patterns in the Yangtze River Economic Belt of China

The intensifying impact of global climate change has led to increased attention being paid to carbon dioxide (CO2) emissions and sinks. However, it remains a challenge to accurately assess and map the spatial distribution of CO2 emissions and sinks. Previous studies have primarily focused on national and provincial-level research, leaving city-level studies relatively overlooked. Acknowledging the significance of interregional differences and the crucial ecological and economic aspects of the Yangtze River Economic Belt (YREB), we devised a research framework to analyse spatio-temporal patterns through city-level CO2 emissions and sinks. The city-level CO2 emissions were estimated using provincial data and linear allocation models, while CO2 sinks were estimated based on the areas of ecosystems and their corresponding sink coefficients. The analysis of YERB's spatio-temporal patterns focuses on regional hotspots, outliers, and time-series clustering. The findings show that: (1) Between 2010 and 2019, ecosystems within YREB absorbed approximately 41.17% to 46.70% of CO2 emissions, with the increase rate of CO2 emissions being lower than that of sinks. (2) City-level CO2 in Western Region of YREB exhibited low emissions and high sinks, while Eastern Region showed high emissions and low sinks, and these characteristics were intensifying. (3) City-level CO2 emissions and sinks demonstrated a "core-periphery" clustering pattern. (4) The regional CO2 balance was predominantly driven by most cities in Eastern Region. This study provides a comprehensive understanding of CO2 emissions and sinks at the city level and offers valuable insights for developing regional collaborative emission reduction strategies in YREB.