Dipole Pattern of Summer Ozone Pollution in the east of China and Its Connection with Climate Variability
Surface O 3 pollution has become one of the most severe air pollution problems in China, which makes it of practical importance to understand O 3 variability. A south-north dipole pattern of summer-mean O 3 concentration in the east of China (DP-O 3 ), which were centered at North China (NC) and the...
| Main Authors: | , |
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| Format: | Text |
| Language: | English |
| Published: |
2021
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| Subjects: | |
| Online Access: | https://doi.org/10.5194/acp-2021-613 https://acp.copernicus.org/preprints/acp-2021-613/ |
| Summary: | Surface O 3 pollution has become one of the most severe air pollution problems in China, which makes it of practical importance to understand O 3 variability. A south-north dipole pattern of summer-mean O 3 concentration in the east of China (DP-O 3 ), which were centered at North China (NC) and the Pearl River Delta (PRD) respectively, has been identified from the simulation of a global 3-D chemical transport model for the period 1980–2019. Large-scale anticyclonic (cyclonic) and cyclonic (anticyclonic) anomalies over NC and the PRD resulted in a sharp contrast of meteorological conditions between the above two regions. The enhanced (restrained) photochemistry and natural emissions of O 3 precursors in NC and restrained (enhanced) O 3 production in the PRD contributed to the DP-O 3 . Decreased sea ice anomalies near the Franz Josef Land and associated warm sea surface in May enhanced the Rossby-wave source over northern Europe and West Siberia, which eventually induced an anomalous Eurasia-like pattern to influence the formation of the DP-O 3 . The thermodynamic signals of the southern Indian Ocean dipole were stored in the subsurface and influenced spatial pattern of O 3 pollution in the east of China mainly through the Hadley circulation. The physical mechanisms behind the modulation of the atmospheric circulations and related DP-O 3 by these two climate anomalies at different latitudes were evidently verified by large-scale ensemble simulations of the earth system model. |
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