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<p>Surface <span class="inline-formula">O₃</span> pollution has become one of the most severe air pollution problems in China, which makes it of practical importance to understand <span class="inline-formula">O₃</span> variability. A south–north dipole pattern of summer-mean <span class="inline-formula">O₃</span> concentration in the east of China (DP-<span class="inline-formula">O₃</span>), which was centered in North China (NC) and the Pearl River Delta (PRD), 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 in NC and restrained (enhanced) <span class="inline-formula">O₃</span> production in the PRD contributed to the DP-<span class="inline-formula">O₃</span>. Decreased sea ice anomalies near 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-<span class="inline-formula">O₃</span>. The thermodynamic signals of the southern Indian Ocean dipole were stored in the subsurface and influenced the spatial pattern of <span class="inline-formula">O₃</span> pollution in the east of China mainly through the Hadley circulation. The physical mechanisms behind the modulation of the atmospheric circulations and related DP-<span class="inline-formula">O₃</span> by these two climate anomalies at different latitudes were evidently verified by large-scale ensemble simulations of the Earth system model.</p>