Integration and Testing of a Disjunct Eddy Accumulation VOC Flux Measurement System in a Research Aircraft

Biogenic Volatile Organic Compound (BVOC) fluxes can now be measured using Disjunct Eddy Accumulation (DEA). This method is primarily applied from fixed towers above forest canopies to study biosphere-atmosphere exchange processes. To expand these tower-based BVOC measurements to spatial scales beyond the tower footprint, an aircraft-based DEA platform is required. Among the significant challenges to such an approach is the capability to determine the vertical component of atmospheric wind from the aircraft with adequate precision and accuracy. The design of a suitable airborne sampling system is another significant challenge. The development of the Airborne Laboratory for Atmospheric Research (ALAR) is described herein. We describe the DEA design and installation along with calibration results which characterize the uncertainties of the vertical wind component measurement. We also describe initial tests of the DEA sampling system, the capabilities of the final installation, and the expected flux uncertainties.