Relationship between aerosol parameters and air masses in central Russia

According to results of long-term measurements in the Moscow region, relationships between parameters of the near-surface aerosol and directions of air masses arrival were analyzed. The results for 2004, 2006, 2007, 2010, and 2011 were taken into consideration. The data were obtained with a spectropolarimeter. Three-day back trajectories were calculated using a standard NOAA HYSPLIT program. All possible directions of arrival of air masses were divided into eight sectors. A trajectory belonging to a certain sector was defined by its initial point and trajectory shape. The basic characteristics of aerosol, mass concentration M and the Hanel parameter, were averaged over a sector. A narrow maximum in the Baltic region and North Atlantic sectors were identified in the frequency distribution of trajectories. The mass concentration maximum falls in the Ukraine-Mediterranean sector. Average values of the Hanel parameter do not depend on the direction of air mass arrival to the observational site. The averaged time distribution of trajectories distinctly shows periodic peaks with a period of about 11–12 weeks for Baltic region-Russian Atlantic and Western Arctic-Polar Urals sectors. In other sectors, their time distributions are relatively uniform.