HALO measures emissions of Asian megacities

Emissions of large cities and urban agglomerations can spread far beyond the borders of the metropolises in certain weather conditions. Particles and gaseous pollutants are often carried by the wind for more than 1,000 kilometers. In March and April 2018, the DLR Institute of Atmospheric Physics (IPA) carried out extensive measurements of the composition and propagation of emissions from Asian megacities using the HALO research aircraft. The measurements complement studies for European metropolitan areas in the summer of 2017 and are part of the international project EMeRGe (Effect of Megacities on the Transport and Transformation of Pollutants on the Regional and Global Scales), which is headed by the University of Bremen. The aim of EMeRGe is to investigate the air pollution of population centers in order to better understand and predict their effects on the composition of the Earth's atmosphere and the climate. In detail, it will be investigated how atmospheric emissions in different weather conditions in Europe and Asia spread and convert into secondary photooxidants and aerosol particles.
The research aircraft HALO was stationed for four weeks at Tainan Airport in Taiwan for EMeRGe. From there, measurement flights were made into the large-scale emission plumes of megacities in China, Japan, the Philippines and Taiwan. The measurement instrumentation of the DLR-IPA included devices for the detection of important gaseous pollutants and greenhouse gases (NOx, SO2, CO, O3, VOC, CH4, CO2) as well as aerosols.
In addition, IPA has contributed to the scientific planning of measurement flights with meteorological forecasts and transport simulations of air mass tracers. First evaluations show that the flights into the pollution plumes of the various megacities could be carried out very successfully. The results of the measurement flights will be presented at an EMeRGe workshop in autumn in Bremen.
Apart from the University of Bremen, project partners are the Max Planck Institute for Chemistry, the Universities of Mainz, Heidelberg and Wuppertal, the Karlsruhe Institute of Technology (KIT) and the Research Center Jülich.