Source-receptor relationship of transboundary particulate matter pollution between China, South Korea and Japan: Approaches, current understanding and limitations

Transboundary particulate matter (PM) pollution in Northeast Asia has raised tremendous concerns in China, South Korea, and Japan, leading to a proliferation of publications in recent years. This article summarizes the existing knowledge on the source-receptor relationship (SRR) of transboundary PM pollution between China, South Korea, and Japan with a focus on approaches, current understanding, and limitations. We found that eastern-, northern- and northeastern China are the most contributing source areas within China to PM pollution in both South Korea and Japan, but it remains debatable whether China contributes more PM pollution to South Korea or Japan than those countries themselves. Considerable differences have been reported in the estimations of China's relative contributions to receptor countries, and higher estimations were usually obtained from studies that focused on short time periods, used outdated emission inventories, and had few or no international collaboration. China's contributions range from 26% to 56% for South Korea and from 13.6% to 53.9% for Japan if the analysis periods are limited to one or several years and the receptors are limited to an entire country. We attributed these differences to the discrepancies in the analysis periods, analytical approaches, modeling settings, definitions of source and receptors, and international collaboration. We also demonstrated that current SRR studies face the challenges from data quality issues in PM measurement data and emission inventories, limited temporal and spatial scales in modeling, and limited analytical perspectives concerning the allocation of environmental responsibilities. Suggestions for future research are provided to address these challenges.

Automated summary

Transboundary particulate matter (PM) pollution in Northeast Asia has attracted significant attention in China, South Korea, and Japan. Studies on the source-receptor relationship (SRR) indicate that China is a major contributor to PM pollution in South Korea and Japan, but the exact contribution remains debated. Factors influencing China's contributions to receptor countries include analysis periods, analytical approaches, data quality, and international collaboration. Challenges in current SRR studies include data quality issues, limited modeling scales, and narrow perspectives on environmental responsibility allocation.