Abstract
Biogenic volatile organic compounds (BVOCs) were measured on tethered balloon platforms in 11 deployments between 1985 and 1996. A series of balloon sampling packages have been used to describe boundary layer dynamics, BVOC distribution, chemical transformations of BVOCs, and to estimate BVOC emission rates from terrestrial vegetation. Measurements indicated a slow decrease of concentration for BVOCs with altitude in the mixed layer when sampling times were greater than average convective turnover time; surface layer concentrations were more variable because of proximity to various emission sources in the smaller surface layer footprint. Mixed layer concentrations of isoprene remained fairly constant in the middle of the day, in contrast to canopy-level isoprene concentrations, which continued to increase until early evening. Daytime emissions, which increase with temperature and light, appear to be balanced by changes in entrainment and oxidation. Daytime measurements of methacrolein and methyl vinyl ketone, reaction products of the atmospheric oxidation of isoprene, showed fairly constant ratio to each other with altitude throughout the mixed layer. BVOC emission flux estimates using balloon measurements and from the extrapolation of leaf level emissions to the landscape scale were in good agreement.
Highlights
The composition of the Earth’s atmosphere is largely a product of biological activity at the surface (Brasseur et al, 1998)
This paper describes a series of experiments using tethered balloon sampling systems to measure Biogenic volatile organic compounds (BVOCs) in the atmospheric boundary layer
A flow-controlling pump was installed. This enabled sampling onto solid adsorbent cartridges, which increased the number of volatile organic compounds (VOCs) which could be measured
Summary
The composition of the Earth’s atmosphere is largely a product of biological activity at the surface While good success has been achieved at the leaf level in understanding the environmental factors which control those emissions, the extrapolation of leaf level measurements to landscapes requires exhausting detail in landscape characterization and monitoring of environmental variables This is achievable in some landscapes where species diversity is small, but it is extremely difficult in areas not well characterized or where species diversity is high (e.g. tropical forests). This paper describes a series of experiments using tethered balloon sampling systems to measure BVOCs in the atmospheric boundary layer These experiments began with the NASA Amazon Boundary Layer Experiment in 1985 and continued at various US landscapes through 1996. During this time there has been adaptation and refinement of tethered balloon sampling techniques to more adequately investigate biogenic emissions, their distribution in the atmospheric boundary layer, the chemistry of BVOCs, and boundary layer meteorology.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
