Airborne aerosol flux measurements with eddy correlation above the ocean in a coastal environment

This work is a first pilot study of particle eddy correlation flux measurements from an aircraft using a condensation particle counter. The study reports aerosol flux measurements from an airplane conducted at approximately 33 m altitude above the ocean in the coastal region of Monterey Bay. The systematic and random uncertainties of such measurements are evaluated. Covariance was calculated for 200 s time series sampled at 10 Hz at 50ms-1 airspeed. Systematic and random uncertainties of flux measurements errors are originated from turbulence measurements errors, counter slow response time and particle counting statistics. The flux error was found to be on order of 0.1–0.3×1060.3×106 particles m-2s-1, for ambient aerosol concentration in the range of 1000–1500 particles cm-3cm-3. The direct effect of oceanic emissions (sea-salt or organic aerosol) on measured local aerosol fluxes was minimal in the studied coastal region due to ship emitted abundant anthropogenic particles.