In recent years, haze pollution events in Beijing have increased sharply, and the haze pollution of Beijing in October 2016 reached a new high. Meteorological conditions are thought to have influences on the haze occu...In recent years, haze pollution events in Beijing have increased sharply, and the haze pollution of Beijing in October 2016 reached a new high. Meteorological conditions are thought to have influences on the haze occurrence, yet the associated atmospheric circulation of haze in October and why the most severe haze pollution occurred in 2016 is still unclear. Here, the authors show through daily observation and reanalysis data that key regions of North Atlantic and North Pacific sea surface temperature （SST） anomalies may be the main factors for this most severe haze event. Since 2013, the SSTs of these two key regions have increased dramatically and reached a peak, which could have induced the severe haze pollution by affecting the Eurasia teleconnection （EU） and the North Pacific Oscillation, with these factors then providing favorable dynamic and thermodynamic conditions for haze development.展开更多
This study reveals that, during the period 1966-2014, dust weather frequency （DWF） in northern China （north of 30°N） features two high-DWF periods, in 1966-1979 （PI） and 2000-2014 （P2）, when the linear tr...This study reveals that, during the period 1966-2014, dust weather frequency （DWF） in northern China （north of 30°N） features two high-DWF periods, in 1966-1979 （PI） and 2000-2014 （P2）, when the linear trend of DWF is removed during the study period. Here, DWF denotes the number of days of dust weather events in the spring season （March-April-May）, including dust haze, blowing dust, and dust storms, which occurred in northern China. The results show that the DWF is much higher in PI than in P2, with increased DWF distributed over southern Xinjiang, the central part of northern China. The main cause is the SST difference in the Atlantic and Pacific between the two periods. It is also found that a meridional teleconnection over East Asia in PI and a zonal wave-like pattern over Eurasia in P2 at 200 hPa play a significant role in the interannual variability in the two periods, respectively. SST over the subtropical North Atlantic （extratropical SST between the Norwegian and Barents seas） may partly contribute to the upper-level meridional （zonal） teleconnection in PI （P2）.展开更多
基金supported by the National Key Research and Development Program of China[grant number2016YFA0600703]National Science Foundation of China[grant number 41421004]Chinese Academy of Sciences-Peking University(CAS-PKU)partnership program
文摘In recent years, haze pollution events in Beijing have increased sharply, and the haze pollution of Beijing in October 2016 reached a new high. Meteorological conditions are thought to have influences on the haze occurrence, yet the associated atmospheric circulation of haze in October and why the most severe haze pollution occurred in 2016 is still unclear. Here, the authors show through daily observation and reanalysis data that key regions of North Atlantic and North Pacific sea surface temperature （SST） anomalies may be the main factors for this most severe haze event. Since 2013, the SSTs of these two key regions have increased dramatically and reached a peak, which could have induced the severe haze pollution by affecting the Eurasia teleconnection （EU） and the North Pacific Oscillation, with these factors then providing favorable dynamic and thermodynamic conditions for haze development.
基金supported by the National Natural Science Foundation of China[grant numbers 41325018,41575079,41421004]
文摘This study reveals that, during the period 1966-2014, dust weather frequency （DWF） in northern China （north of 30°N） features two high-DWF periods, in 1966-1979 （PI） and 2000-2014 （P2）, when the linear trend of DWF is removed during the study period. Here, DWF denotes the number of days of dust weather events in the spring season （March-April-May）, including dust haze, blowing dust, and dust storms, which occurred in northern China. The results show that the DWF is much higher in PI than in P2, with increased DWF distributed over southern Xinjiang, the central part of northern China. The main cause is the SST difference in the Atlantic and Pacific between the two periods. It is also found that a meridional teleconnection over East Asia in PI and a zonal wave-like pattern over Eurasia in P2 at 200 hPa play a significant role in the interannual variability in the two periods, respectively. SST over the subtropical North Atlantic （extratropical SST between the Norwegian and Barents seas） may partly contribute to the upper-level meridional （zonal） teleconnection in PI （P2）.
