Modification of a Commercial Condensation Particle Counter for Boundary Layer Balloon-Borne Aerosol Studies

Abstract

A commercial battery-driven condensation particle counter (TSI-8020) was modified for use in a lightweight payload for tethered balloons to study new particle formation in the planetary boundary layer. After modifications, the instrument was characterized and calibrated over the particle size range 5 ? Dp ? 1000 nm and an air pressure range down to 600 hPa. In 1996, the single-channel instrument was deployed in its first field campaign at a rural research station in eastern Germany, where the instrument clearly indicated new particle formation near the top of a low stratus deck. A first field test with the double-CPC (condensation particle counter) payload demonstrated the feasibility of jointly measuring number concentrations for Dp ≥ 6 nm and Dp ≥ 12 nm on the same balloon payload. The difference of the two count signals provides a good measure of new particle formation.