Abstract:
Longfengshan Regional Atmospheric Background Station is one of a few atmospheric background pollution monitoring stations at mid- and high-latitude regions in East Asia, and it is also one of the WMO GAW regional stations. The characteristics of weather and climate at Longfengshan station are summarized. The regional distribution and seasonal variation of the airflow to the station are analyzed by trajectories calculation and clustering technique using the 2009-2010 NCEP reanalysis data. In summer, as the establishment and pushing forward of the southwest monsoon, the airflow from regions around the BohaiBaycan move north alongLiaoning,Jilinprovinces and arrived at the station. In winter, due to the influence of the monsoon circulation, the northwest and northern airflow passing overQiqihar, Daqing,Harbinand other large industrial city have a significant influence. The airflow with a relatively slow movement and from the Northeast Plain of China can be transported to the station in different seasons. For decades, at Longfengshan station, it has accumulated a lot of basic data, including conventional ground-based meteorological parameters, solar radiation, greenhouse gases, aerosols, reactive gases, precipitation chemistry, ground-base remote sensing, which is of seven major categories with more than 30 kinds of observation elements. The observational studies show that the concentrations of primary pollutants (such as SO2, NOx) and [NH4 +], [SO42-] and [NO3-]ions in precipitation have a significant increase when compared to the levels of 10 years ago, and the pH value in precipitation shows a downward trend.