TY - JOUR
T1 - Large-scale synoptic drivers of co-occurring summertime ozone and PM2.5 pollution in eastern China
AU - Zong, Lian
AU - Yang, Yuanjian
AU - Gao, Meng
AU - Wang, Hong
AU - Wang, Peng
AU - Zhang, Hongliang
AU - Wang, Linlin
AU - Ning, Guicai
AU - Liu, Chao
AU - Li, Yubin
AU - Gao, Zhiqiu
N1 - Funding Information:
This research has been supported by the National Natural Science Foundation of China (grant nos. 42061134009, 42075072, and 41575010) and the National Key Research and Development Program of China (grant no. 2018YFC1506502).
Publisher Copyright:
© Author(s) 2021.
PY - 2021/6/15
Y1 - 2021/6/15
N2 - Surface ozone (O3) pollution during summer (June–August) over eastern
China has become more severe in recent years, resulting in a co-occurrence
of surface O3 and PM2.5 (particulate matter with aerodynamic
diameters ≤ 2.5 µm in the air) pollution. However, the mechanisms
regarding how the synoptic weather pattern (SWP) might influence this compound
pollution remain unclear. In this study, we applied the T-mode principal
component analysis (T-PCA) method to objectively classify the occurrence of
four SWPs over eastern China, based on the
geopotential heights at 500 hPa during summer (2015–2018). These four SWPs
over eastern China were closely related to the western Pacific subtropical
high (WPSH), exhibiting significant intra-seasonal and interannual
variations. Based on ground-level air quality observations, remarkable
spatial and temporal disparities of surface O3 and PM2.5 pollution
were also found under the four SWPs. In particular, there were two SWPs that
were sensitive to compound pollution (Type 1 and Type 2). Type 1 was
characterized by a stable WPSH ridge with its axis at about 22∘ N
and the rain belt located south of the Yangtze River Delta (YRD); Type 2 also exhibited WPSH dominance (ridge axis at ∼ 25∘ N) but with the rain belt (over the YRD) at a higher latitude
compared to Type 1. In general, SWPs have played an important role as
driving factors of surface O3–PM2.5 compound pollution in a
regional context. Our findings demonstrate the important role played by SWPs
in driving regional surface O3–PM2.5 compound pollution, in
addition to the large quantities of emissions, and may also provide insights
into the regional co-occurring high levels of both PM2.5 and O3
via the effects of certain meteorological factors.
AB - Surface ozone (O3) pollution during summer (June–August) over eastern
China has become more severe in recent years, resulting in a co-occurrence
of surface O3 and PM2.5 (particulate matter with aerodynamic
diameters ≤ 2.5 µm in the air) pollution. However, the mechanisms
regarding how the synoptic weather pattern (SWP) might influence this compound
pollution remain unclear. In this study, we applied the T-mode principal
component analysis (T-PCA) method to objectively classify the occurrence of
four SWPs over eastern China, based on the
geopotential heights at 500 hPa during summer (2015–2018). These four SWPs
over eastern China were closely related to the western Pacific subtropical
high (WPSH), exhibiting significant intra-seasonal and interannual
variations. Based on ground-level air quality observations, remarkable
spatial and temporal disparities of surface O3 and PM2.5 pollution
were also found under the four SWPs. In particular, there were two SWPs that
were sensitive to compound pollution (Type 1 and Type 2). Type 1 was
characterized by a stable WPSH ridge with its axis at about 22∘ N
and the rain belt located south of the Yangtze River Delta (YRD); Type 2 also exhibited WPSH dominance (ridge axis at ∼ 25∘ N) but with the rain belt (over the YRD) at a higher latitude
compared to Type 1. In general, SWPs have played an important role as
driving factors of surface O3–PM2.5 compound pollution in a
regional context. Our findings demonstrate the important role played by SWPs
in driving regional surface O3–PM2.5 compound pollution, in
addition to the large quantities of emissions, and may also provide insights
into the regional co-occurring high levels of both PM2.5 and O3
via the effects of certain meteorological factors.
UR - http://www.scopus.com/inward/record.url?scp=85108170711&partnerID=8YFLogxK
U2 - 10.5194/acp-21-9105-2021
DO - 10.5194/acp-21-9105-2021
M3 - Journal article
AN - SCOPUS:85108170711
SN - 1680-7316
VL - 21
SP - 9105
EP - 9124
JO - Atmospheric Chemistry and Physics
JF - Atmospheric Chemistry and Physics
IS - 11
ER -