Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 6 5 2006 10.5194/acpd-6-10567-2006 http://www.atmos-chem-phys-discuss.net/6/10567/2006/ http://www.atmos-chem-phys-discuss.net/6/10567/2006/acpd-6-10567-2006.html http://www.atmos-chem-phys-discuss.net/6/10567/2006/acpd-6-10567-2006.pdf 10567 10589 2006-10-18 Boundary layer concentrations and landscape scale emissions of volatile organic compounds in early spring S. Haapanala J. Rinne H. Hakola H. Hellén L. Laakso H. Lihavainen R. Janson M. Kulmala University of Helsinki, Department of Physical Sciences, Helsinki, Finland Finnish Meteorological Institute, Air Chemistry Laboratory, Helsinki, Finland Finnish Meteorological Institute, Climate and Global Change Research, Helsinki, Finland Stockholm University, Department of Applied Environmental Science, Stockholm, Sweden Boundary layer concenrations of several volatile organic compounds (VOC) were measured during two campaigns in springs of 2003 and 2006. Measurements were conducted over boreal forests near SMEAR II measurement station in Hyytiälä, Southern Finland. In 2003 the measuremens were performed using light aircraft and in 2006 using hot air ballon. Isoprene concentrarions were low, usually below detection limit. This is explained by low biogenic production due to cold weather. Monoterpenes were observed frequently. Average total monoterpene concentration in the boundary layer was 33 ppt_v. Many anthropogenic compounds e.g. benzene, xylene and toluene, were observed in high amounts. Ecosystem scale surface emissions were estimated using simple mixed box budget methodology. Total monoterpene fluxes varied up to 80 μg m^−2 h^−1, α-pinene contributing typically more than two thirds of that. Highest fluxes of anthropogenic compounds were those of p/m xylene.