AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Seasonal Cycles of Fluorescent Biological Particles in Finland and Colorado Forests
Carolyn J. Schumacher, Christopher Pöhlker, Pasi Aalto, Markku Kulmala, Ulrich Pöschl, J. ALEX HUFFMAN, University of Denver
Abstract Number: 558 Working Group: Bioaerosols: Characterization and Environmental Impact
Abstract Biogenic aerosols are ubiquitous in the Earth’s atmosphere, influencing atmospheric chemistry and physics, the biosphere, climate, and public health. They play an important role in the spread of biological organisms, can cause diseases, and may form nuclei which initiate water (CCN) and ice (IN) cloud formation.
The ultraviolet aerodynamic particle sizer (UV-APS) measures the concentration and aerodynamic diameter of particles in the size range of 1–20 micro-meter by light scattering and time-of-flight measurement, complemented by the measurement of fluorescence emission. The instrument provides real-time detection of fluorescent biological aerosol particles (FBAP) as a lower-limit proxy of coarse-mode primary biological aerosol particles (PBAP) with relatively high time and size resolution.
The UV-APS was operated in a European boreal forest (Hyytiälä, Finland) and a semi-arid, North American pine forest (Manitou Forest, Colorado) continuously for 18-months and 11-months, respectively, to monitor the seasonal cycles of coarse aerosol. FBAP concentrations peaked during summer and were lowest in winter at both locations and showed strong contrast to non-fluorescent aerosol seasonality. Additionally, we observed differences in the relationship between FBAP and temperature, relative humidity, and rainfall as a function of season suggesting that factors influencing bioaerosol emission change through the course of the year.