Phasic variations of winter Beijing haze and its possible association with Arctic sea ice loss

Abstract

The continuous melting of Arctic sea ice affects the spatial distribution of the air temperature field in the Arctic–Eurasia and then modulates the winter haze days in Beijing to produce phased changes. The interdecadal variation of winter haze days in Beijing has a high consistency with the periodic fluctuation of winter air temperature in the Mongolian Plateau. The warmer Mongolia Plateau corresponds to more haze days, while the colder Mongolia Plateau corresponds to less haze days. The temperature variation in the Mongolian Plateau is affected by the Arctic–Eurasia temperature spatial pattern and also shows obvious low-frequency variation characteristics after 2004. The numerical simulation experiment of Arctic sea ice forcing can reproduce the above characteristics of temperature distribution, and the key circulation field anomaly configuration that affects the periodic change of haze days in Beijing can also be simulated. The model results show that the continuous melting of Arctic sea ice has an important contribution to the low-frequency variation of winter haze days in Beijing, and the continuous melting of Arctic sea ice causes the alternating distribution of warm Arctic—cold Eurasian and warm Arctic—warm Eurasian patterns by affecting the atmospheric circulation in mid-high latitude in winter, which is conducive to the staged change of winter haze days in Beijing.