Determination of a vertical profile of black carbon by a combined application of a light research aircraft and a quadcopter unmanned aerial vehicle - a case study using an airborne ultraportable micro-aethalometer for black carbon measurements at a rural site in Germany

摘要

Black carbon (BC) is a constituent of many sorts of particulate matter. Unfortunately, it is well known from several medical studies that black carbon is very harmful to human health. The active surface can be porous to a high degree and can attract toxics. BC has a small particle size, has a graphitic structure, and is optically black. Additionally to his adverse health effects it can influence atmospheric precipitation, cloud nucleation and climate. BC is produced more or less by all fossil combustion processes. However, until now it is difficult to model the contributions of BC by different combustion sources, so that it is important to get reliable measurement results of BC. Whereas health effects on human beings are depend on their individual exposure, atmospheric effects of BC depend on the larger scale distribution in the atmosphere. In this paper a new approach is used to determine the distribution of BC in the atmosphere: Measurements of a light research aircraft are combined with measurements using a quadcopter unmanned aerial vehicle (UAV). Whereas the light research aircraft can investigate the troposphere from 150m up to 7000m altitude, the quadcopter UAV can sample the atmosphere between ground level and 500m altitude, so giving a spatial measurement overlap for comparison and quality assurance. Moreover, not only vertical concentration profiles of BC in the atmosphere can be achieved, but horizontal profiles as well. In this paper we present a case study of combined measurements with a light research aircraft and a quadcopter UAV, both equipped with aethalometer instruments for the measurement of profiles of BC. A rural site in Germany was chosen for this experiment (Melpitz). The research aircraft and the UAV were both equipped with mobile aethalometers for the measurement of BC, however, the UAV carried an innovative ultraportable aethalometer. Both aethalometers were compared and calibrated in the laboratory with reference BC measurement systems before the airborne field use. Moreover, for the first time the results of the airborne combined measurement of BC by a light research aircraft and an UAV are presented.