Properties of Aged Forest Fire Plumes after Intercontinental Transport across the Atlantic Ocean

Abstract

In summer 2004 the long-range transport of particles emitted from large forest fires in Canada and Alaska contributed significantly to the aerosol loading of the free troposphere over Europe . Airborne in situ measurements on the intercontinental transport of aerosols from biogenic and anthropogenic origin were performed at the European west coast as a part of the ICARTT-ITOP study (Intercontinental Transport of Ozone and Precursors). During the study the German Falcon 20 E-5 research aircraft was operating from an airport north of Paris. The aircraft was equipped with extensive in-situ aerosol and trace gas instrumentation. Measurement flights were performed over the European west coast probing the entire tropospheric column from the boundary layer to the upper free troposphere. Trajectory analyses were conducted for all the measurement flights and permitted the identification of the plume origin for several forest fires cases. Simultaneously to the airborne in-situ measurements, black carbon data from the high-alpine research station Jungfraujoch (JFJ; 3580 m asl) in Switzerland showed elevated BC levels during this period. Trajectory analyses confirmed that the JFJ station was probing the same forest fire plume as the Falcon during the measurement flights at the European West coast.