caa a22 4500 475823656 CHVBK 20180406123825.0 cr unu---uuuuu 170329e20000301xx s 000 0 eng 10.1023/A:1006301121309 doi (NATIONALLICENCE)springer-10.1023/A:1006301121309 A Lagrangian Study of the Three-Dimensional Transport of Boundary-Layer Tracers in an Idealised Baroclinic-Wave Life-Cycle [Elektronische Daten] [K.-Y. Wang, D. Shallcross] The role of baroclinic-wave driven chemical transport is examined using the framework of a Lagrangiantrajectory model.The Lagrangian motion of transported trace gases are closely monitored through labelledboundary-layer tracers binned accordingto their latitudinal locations.From a set of 14-day Lagrangian paths, the mechanistically liftedsubtropical boundary-layer tracers track along tilted poleward paths, whilethe subsiding high-latitude tracers track along tilted equator-ward paths.The most significantmovements of tracers occur between days 6 and8. The vertical and latitudinal displacements during this time interval are3 km and 15° latitude. During a baroclinic-wave life-cycle,boundary-layertracers can either ascend vertically from 1 km to 7 km or descend to thesurface, while they arelatitudinally transported from 37° to 73° and from 45° to near 15° during the poleward and equator-ward motions,respectively.Vertical mixing of tracers occurs vigorously at mid-latitudes, where more than50%, by day 7, and a maximum of 70%, between days 9 and 10, of the boundary layer tracers have beentransported intothe free troposphere during the baroclinic-wave life-cycle.A clear 3D picture emerges from a Lagrangian analysis.Each time the tracer travels equator-ward, it descends, whilewhen it travels poleward, it ascends.Almost all of the low latitude tracers show tilted upward and poleward paths,while high latitude tracersshows downward tilted and equator-ward path.The maximum vertical displacement between poleward andequator-ward tracers are shown in mid-latitudes.Two types of the tilted upward and poleward paths are generally seen in thelatitude-height projections:anti-clockwise and clockwise paths.Both types of path transport tracers upward, however, the anti-clockwise pathsdeliver tracersequator-ward, while the clockwise paths deliver tracers poleward.Hence, whenlow latitude warm air arrives at mid-latitude, it can pick up enhanced tracerconcentrationand carry them on either poleward or equator-ward. Kluwer Academic Publishers, 2000 Lagrangian motion nationallicence baroclinic wave nationallicence tracer transport nationallicence Wang K.-Y Center for Atmospheric Science, Cambridge University, Lensfield Road, CB2 1EW, Cambridge, U.K. aut Shallcross D. Center for Atmospheric Science, Cambridge University, Lensfield Road, CB2 1EW, Cambridge, U.K. aut Journal of Atmospheric Chemistry Kluwer Academic Publishers 35/3(2000-03-01), 227-247 0167-7764 35:3<227 2000 35 10874 https://doi.org/10.1023/A:1006301121309 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1006301121309 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wang K.-Y Center for Atmospheric Science, Cambridge University, Lensfield Road, CB2 1EW, Cambridge, U.K aut NATIONALLICENCE 700 1- Shallcross D. Center for Atmospheric Science, Cambridge University, Lensfield Road, CB2 1EW, Cambridge, U.K aut NATIONALLICENCE 773 0- Journal of Atmospheric Chemistry Kluwer Academic Publishers 35/3(2000-03-01), 227-247 0167-7764 35:3<227 2000 35 10874 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer