CARIBIC—Civil Aircraft for Global Measurement of Trace Gases and Aerosols in the Tropopause Region

Abstract

The deployment of measurement equipment in passenger aircraft for the observation of atmospheric trace constituents is described. The package of automated instruments that is installed in a one-ton-capacity aircraft freight container positioned in the forward cargo bay of a Boeing 767 ER can register a vast amount of atmospheric data during regular long-distance flights. The air inlet system that is mounted on the fuselage directly below the container comprises an aerosol inlet, a separate inlet for trace-gas sampling, and an air exhaust. All instruments, the central computer, and power supply are mounted in aviation-approved racks that slide into the reinforced container. The current instrument package comprises a fast-response chemiluminescence sensor and a conventional UV absorption detector for O3; a gas chromatograph for CO; two condensation nuclei counters for particles larger than 5 and 12 nm; and a 12-canister large-capacity whole air sampler for laboratory trace-gas analysis and isotopic analysis of CO2, CO, CH4, and N20. First measurement results of the operational Civil Aircraft for Remote Sensing and In Situ Measurements in Troposphere and Lower Stratosphere Based on the Instrumentation Container Concept (CARIBIC) container are reported.