Title Quantifying transport into the Arctic lowermost stratosphere
Author Werner, A.; Volk, C.M.; Ivanova, E.V.; Wetter, T.; Schiller, C.; Schlager, H.; Konopka, P.
Author Affil Werner, A., Johann Wolfgang Goethe Universität Frankfurt am Main, Institut für Atmosphäre und Umwelt, Frankfurt, Germany. Other: Forschungszentrum Jülich, Germany; Deutsches Zentrum für Luft und Raumfahrt, Germany
Source Atmospheric Chemistry and Physics, 10(23), p.11623-11639, . Publisher: Copernicus, Katlenburg-Lindau, International. ISSN: 1680-7316
Publication Date 2010
Notes In English. Includes appendices; published in Atmospheric Chemistry and Physics Discussions: 15 January 2009, http://www.atmos-chem-phys- discuss.net/9/1407/2009/acpd-9-1407- 2009.html; accessed in June, 2011. 63 refs. GeoRef Acc. No: 309974
Index Terms atmospheric circulation; chemical composition; climate; gases; hydrocarbons; mass balance; ozone; statistical analysis; stratosphere; temperature; microelement content; water; water temperature; Arctic region; Sweden; aliphatic hydrocarbons; alkanes; Arctic vortex; atmospheric transport; boundary conditions; bromochlordifluoromethane; Europe; least- squares analysis; methane; nitrous oxide; organic compounds; Scandinavia; seasonal variations; trace elements; transport; trichlorofluoromethane; troposphere; Western Europe
Abstract In the Arctic winter 2003, in-situ measurements of the long-lived trace gases N2O, CFC-11 (CCl3F), H-1211 (CBrClF2), CH4, O3 and H2O have been performed on board the high-altitude aircraft M55 Geophysica. The data are presented and used to study transport into the lowermost stratosphere (LMS). The LMS can be regarded as a mixture of fractions of air originating in (i) the troposphere, (ii) the extra-vortex stratosphere above 400 K and (iii) the Arctic vortex above 400 K. These fractions are determined using a simple mass balance calculation. The analysis exhibits a strong tropospheric influence of 50%±15% or more in the lowest 20 K of the high-latitude LMS. Above this region the LMS is dominated by air masses having descended from above 400 K. Below the Arctic vortex region at potential temperatures above 360 K, air in the LMS is a mixture of extra-vortex stratospheric and vortex air masses. The vortex fraction increases from about 40%±15% at 360 K to 100% at 400 K for equivalent latitudes ›70°N. This influence of air masses descending through the bottom of the polar vortex increases over the course of the winter. By the end of winter a significant fraction of 30%±10% vortex air in the LMS is found even at an equivalent latitude of 40°N. Since the chemical and dynamical history of vortex air is distinct from that of mid-latitude stratospheric air masses, this study implies that the composition of the mid- to high- latitude LMS during late winter and spring is significantly influenced by the Arctic vortex.
URL http://www.atmos-chem-phys.net/10/11623/2010/acp-10-11623-2010.pdf
Publication Type journal article
Record ID 65006878