The impact of synoptic circulation and long-term circulation change on air quality and pollution-related human health in the Yangtze River Delta region

Zhiheng Liao, Meng Gao, Jiaren Sun, Shaojia Fan

Research output: Chapter in book/report/conference proceedingChapterpeer-review

3 Citations (Scopus)


We extend previous synoptic-scale work to climatological scale to examine the potential effects of long-term circulation changes on surface air quality and pollution-related public health in the Yangtze River Delta (YRD) region. This climatological-scale study detects the long-term circulation trends based on the Lamb weather type technique, quantifies the circulation change-driven PM2.5 and O3 changes using a synoptic downscaling statistical approach, and assesses the circulation change-induced air quality impact on acute mortality using the health impact assessment (HIA) model. The results indicate that synoptic circulation influencing the YRD region experienced a significant decline in negative vorticity during the period from 1979 to 2017. Consequently, the frequency of the anticyclonic pattern decreased by 17.6% from 32.9% in the historical period (1979-83) to 27.1% in the current period (2013-17), and the total occurrence of easterly patterns increased by 33.6%. The long-term circulation changes potentially caused a decrease in the annual PM2.5 concentration of 1.0-3.0µg/m3 (a regional mean decrease of 2.0µg/m3) over the YRD region; but a relatively modest O3 change (a regional mean increase of 0.4µg/m3). These circulation-driven air quality changes (especially PM2.5 change) can be largely explained by the changing transport effects due to weakened East Asian winter monsoon (i.e., increased clean marine sources and decreased polluted continental sources). The increased O3 caused 217 (95% CI: 172, 262) annual acute deaths, but this “climate penalty” was offset by the larger avoided mortality due to the circulation-driven PM2.5 reduction. Overall, long-term circulation changes were responsible for averting 448 (95% CI: 395, 561) annual acute deaths in the YRD region, which suggests a public health “climate benefit.” These findings are anticipated to provide important information for regional climate and air quality forecast, as well as public health management.

Original languageEnglish
Title of host publicationAir Pollution, Climate, and Health
Subtitle of host publicationAn Integrated Perspective on Their Interactions
EditorsMeng Gao, Zifa Wang, Gregory Carmichael
Number of pages27
ISBN (Electronic)9780128203958
ISBN (Print)9780128201237
Publication statusPublished - 14 Apr 2021

Scopus Subject Areas

  • Medicine(all)

User-Defined Keywords

  • Air quality
  • Circulation change
  • Climate change
  • Lamb weather type
  • Premature mortality
  • Yangtze river delta region


Dive into the research topics of 'The impact of synoptic circulation and long-term circulation change on air quality and pollution-related human health in the Yangtze River Delta region'. Together they form a unique fingerprint.

Cite this