Assessing atmospheric CO2 concentrations and contributions from biogenic and anthropogenic sources in the Pearl River Delta region

Abstract

The dynamics of atmospheric CO2 concentrations in urban agglomerations have been a topic of interest in research on global climate change, yet there remain significant uncertainties within the estimates of CO2 contributions from biogenic and anthropogenic sources. In this study, the Weather Research and Forecasting model coupled with the Vegetation Photosynthetic Respiration Model (WRF-VPRM) was implemented with local VPRM parameters to simulate the atmospheric CO2 concentration in the Pearl River Delta (PRD) region of China during 2019–2021. The results show that (1) WRF-VPRM accurately simulates the distribution of the atmospheric CO2 concentration in the PRD region from 36-km grids to 4-km grids, and the CO2 concentrations within the simulated grids demonstrated good consistency. (2) Anthropogenic emissions were the main factor, accounting for 20.59% of the total CO2 concentration in the region; by contrast, the contribution from vegetation emissions was only 1.57%. (3) High CO2 concentration centers (CO2 exceed 436 ppm) occur throughout the year in rural areas of the boundary between Yunfu and Zhaoqing, northeast Qingyuan, and southern Huizhou. CO2 concentrations were below 426 ppm in the region around the Pearl River Estuary in summer and fall.