10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Aerosol Size Distributions in Lower Atmospheric Boundary Layer above Coal Strip Mine by Airborne Measurements
JAN HOVORKA, Miroslav Klán, Milos Zapletal, Jana Esterlova, Jan Bendl, Filip Kobrzek, Petr Marecek, Charles University in Prague
Abstract Number: 977 Working Group: Aerosol Transport and Transformation
Abstract Quantification of atmospheric aerosol emission by large-surface sources, like coal strip mines or agriculture fields, is usually calculated from emission factors. Since the factors significantly vary with the used technology and meteorology and orography of the mine or field play a major role in fugitive aerosol emissions, calculated emission rates significantly differ from real ones. To measure real aerosol emission rates from a large strip mine, eddy-covariant measurements by an unmanned airship carrying an aerodynamic particle sizer were conducted at heights 50-800m aloft a large lignite strip-mine in the Czech Republic in winter 2017/2018. There was a critical height at 350m above the mine bottom, approx. 120m above the edge of the mine, identified in the mine atmospheric boundary layer. Below the critical height, bimodal (0.6 and 6 μm) aerosol particle mass size distribution was recorded then suddenly changed to monomodal distribution at higher altitudes. Mass of submicron particles was constant (15μgm-3) up-to the critical height while significantly dropped (5μgm-3) above the height. In contrast, supermicron particle mass linearly decreased from 90% (max ~1 mgm-3) to 25% (1 μgm-3) at critical height and were constant at higher altitudes. Also, single technologies were detected as rather narrow columnar plumes up-to 80m below the critical height but the plumes were smeared and ceased at higher altitudes. This indicates rather low emission rates of atmospheric aerosol from the mine to neighboring environment under meteorology condition of the measurement. The study is supported by the Czech Science Foundation (P503/12/G147) and Technology Agency of the Czech Republic (TH02030238)