Title Airborne measurements of aerosol optical properties related to early spring transport of mid-latitude sources into the Arctic
Author de Villiers, R.A.; Ancellet, G.; Pelon, J.; Quennehen, B.; Schwarzenboeck, A.; Gayet, J.F.; Law, K.S.
Author Affil de Villiers, R.A., Université Pierre et Marie Curie-Paris VI, Paris, France. Other: Université Blaise Pascal, France
Source Atmospheric Chemistry and Physics, 10(11), p.5011-5030, . Publisher: Copernicus, Katlenburg-Lindau, International. ISSN: 1680- 7316
Publication Date 2010
Notes In English. Includes appendix; part of special issue no. 182, POLARCAT (Polar study using aircraft, remote sensing, surface measurements and models, of climate, chemistry, aerosols, and transport), edited by Stohl, A., et al., http://www.atmos-chem- phys.net/special_issue182.html; published in Atmospheric Chemistry and Physics Discussions: 23 December 2009, http://www.atmos-chem-phys- discuss.net/9/27791/2009/acpd-9-27791-2009.ht ml; accessed in May, 2011. 52 refs. GeoRef Acc. No: 310046
Index Terms aerosols; aerial surveys; airborne radar; backscattering; biomass; fires; human activity; lasers; lidar; optical properties; ozone; particles; pollution; radar; spectra; Scandinavia; Asia--Siberia; Arctic region-- Svalbard; air pollution; airborne methods; Arctic region; Asia; atmospheric transport; CALIOP; CALIPSO; carbon monoxide; eastern Asia; Europe; FLEXPART; in situ; infrared spectra; laser methods; lidar methods; nonpoint sources; pollutants; radar methods; Siberia; smoke; Svalbard; trajectories; transport; troposphere; Western Europe
Abstract Airborne lidar and in-situ measurements of the aerosol properties were conducted between Svalbard Island and Scandinavia in April 2008. Evidence of aerosol transport from Europe and Asia is given. The analysis of the aerosol optical properties based on a multiwavelength lidar (355, 532, 1064 nm) including volume depolarization at 355 nm aims at distinguishing the role of the different aerosol sources (Siberian wild fires, Eastern Asia and European anthropogenic emissions). Combining, first aircraft measurements, second FLEXPART simulations with a calculation of the PBL air fraction originating from the three different mid- latitude source regions, and third level-2 CALIPSO data products (i.e. backscatter coefficient 532 nm,volume depolarization and color ratio between 1064 and 532 nm in aerosol layers) along the transport pathways, appears a valuable approach to identify the role of the different aerosol sources even after a transport time larger than 4 days. Optical depth of the aerosol layers are always rather small (‹4%) while transported over the Arctic and ratio of the total attenuated backscatter (i.e. including molecular contribution) provide more stable result than conventional aerosol backscatter ratio. Above Asia, CALIPSO data indicate more depolarization (up to 15%) and largest color ratio (›0.5) for the northeastern Asia emissions (i.e. an expected mixture of Asian pollution and dust), while low depolarization together with smaller and quasi constant color ratio (~0.3) are observed for the Siberian biomass burning emissions. A similar difference is visible between two layers observed by the aircraft above Scandinavia. The analysis of the time evolution of the aerosol optical properties revealed by CALIPSO between Asia and Scandinavia shows a gradual decrease of the aerosol backscatter, depolarization ratio and color ratio which suggests the removal of the largest particles in the accumulation mode. A similar study conducted for a European plume has shown aerosol optical properties intermediate between the two Asian sources with color ratio never exceeding 0.4 and moderate depolarization ratio being always less than 8%, i.e. less aerosol from the accumulation mode.
URL http://www.atmos-chem-phys.net/10/5011/2010/acp-10-5011-2010.pdf
Publication Type journal article
Record ID 65006806