Frequency of spring dust weather in North China linked to sea ice variability in the Barents Sea

The link between winter sea ice cover in the Barents Sea (SICBS) and the frequency of spring dust weather over North China (DWFNC) is investigated. It is found that year-to-year variability of SICBS and DWFNC are strongly correlated for the period 1996-2014 with a correlation coefficient of -0.65, whereas the correlation between SICBS and DWFNC is not statistically significant for the periods 1980-2014 and 1980-1995. During 1996-2014, low winter SICBS is associated with decreased snow cover over western Siberia (SCWS) in both winter and spring, which is also supported by a strengthening relationship between winter SICBS and spring SCWS since the mid-1990s. This leads to changes in atmospheric circulation and climate conditions that are favorable for increased frequency of dust weather events over North China. Our further analysis suggests that the interannual variability of the standard deviation of SICBS has intensified and the center of actions has moved eastward to the north Barents Sea and Kara Sea since the mid-1990s. Such change may easily induce stronger and southward stationary Rossby wave train propagation, influencing the dust-related atmospheric circulation (strengthened East Asian subtropical jet, increased cyclogenesis, and larger atmospheric thermal instability). Thus interannual variation of winter SICBS plays an increasingly important role in dust-related climate conditions over North China, which might serve as a new precursor for the prediction of spring dust activity in North China.