Aerosol connections between three distant continental stations. (October 2018)

• Record Type: Journal Article
• Authors: Heintzenberg, Jost; Senf, Fabian; Birmili, Wolfram; Wiedensohler, Alfred
• Is Part Of: Atmospheric environment. Volume 190(2018)
• Page Start: 349
• Page End: 358
• Publication Date: 2018-10
• Subjects: Continental aerosol -- Particle number size distribution -- Long-term measurements -- Particle growth -- Sub-cloud aerosol particle scavenging; Air -- Pollution -- Periodicals; Air -- Pollution -- Meteorological aspects -- Periodicals; 551.51
• DOI: 10.1016/j.atmosenv.2018.07.047
• Languages: English
• ISSNs: 1352-2310

Abstract

Abstract: The present study is based on hourly aerosol particle and ancillary data taken at three stations in Northeastern Germany 150–200 km apart in the years 2009 through 2015 in order to investigate systematic process related differences that might show up when connecting their data with forward and backward air mass trajectories. The analysis of changes in the atmospheric aerosol during air mass transport between the stations focused on two low-pollution-to-high-pollution pathways of similar distance around 200 km. Despite rather different initial size distributions the increases in total concentration of particle number, volume, and black carbon agreed within 15%. Systematic variations were found in the different concentration increases as a function of time of day at which an interstation air mass transport took place that could be explained with related source and transport processes. With Radar-based precipitation data at the stations and along connecting trajectories sub-cloud particle scavenging was investigated. At each station sub-cloud particle scavenging coefficients were determined as a function of particle size between 10 and 700 nm diameter, and as a function of precipitation sums. Median particle scavenging coefficients taken over the central part of the size range of the study strongly increased between 0.2 and 1 mm of precipitation and then planed out towards higher precipitation values. With the particle scavenging coefficients determined at the individual stations and precipitation data along connecting trajectories the sub-cloud particle scavenging analysis was extended to wet scavenging along the transport paths yielding median sub-cloud scavenging ratios over the range 0.2–25 mm of precipitation sums with a non-linear shape similar to that of the median particle scavenging coefficients at the individual stations. Whereas in light precipitation more than 80% of the initial particles in the considered range survived 150–200 km of transport, more than 50% was scavenged by more than 15 mm of precipitation during aerosol transport. Highlights: Aerosol data taken at distant stations can be connected via air mass trajectories. Via air mass trajectories three-station aerosol data was extrapolated to a larger region. Particle growth during air mass transport between distant stations was quantified. With radar-derived precipitation along connecting trajectories sub-cloud scavenging between the stations was quantified.