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Modelling tracer transport by a cumulus ensemble: Lateral boundary conditions and large scale ascent. Advective timescale: necessary condition for model results to be meaningful:. CRM. Specified lateral boundary conditions (SLBC, horizontal advection)
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Modelling tracer transport by a cumulus ensemble: Lateral boundary conditions and large scale ascent
Advective timescale: necessary condition for model results to be meaningful: CRM Specified lateral boundary conditions (SLBC, horizontal advection) Advection of tracers by the large scale vertical wind (VLSAT) Previously (Lu et al., 2000): periodic boundary conditions in cumulus ensemble model also for tracers, but no prescribed horizontal LSA for tracers
Specified lateral boundary conditions (SLBC, horizontal advection) Advection of tracers by the large scale vertical wind (VLSAT) Previously: the effect of net large scale ascent e.g. over the Pacific Warm Pool is considered for q, BUT IT WAS NEGLECTED FOR TRACERS
motivation case study of the influence of deep convection on atmospheric chemistry
WRF – Weather Research and Forecast Model developed by NCAR and others 2D or 3D fit for small scale meteorological phenomena www.wrf-model.org
SATELLITE PIC ISCCP clouds IR retrieved cloud top temperatures e.g. Rossow and Schiffer, 1999
1000hPa wind Kalnay et al., 1996
Ciesielski et al., 2003 westerly wind burst
ozone Lawrence et al., 2003 flight dates: 94/02/07-94/03/14 Emmons et al., 2000 Thompson et al., 2003 SHADOZ, WOUDC
large scale advection new: and SLBC
Sensitivity Runs – Idealized Tracers 2D runs, 500km horizontal domain 350m vertical grid spacing in the troposphere Walcek (2000) advection scheme 3(2) different setups: periodic lateral boundary conditions (PLBC, k=1) specified lateral boundary conditions (SLBC, k=0) u, (v), w, q, C= SLBC+VLSAT (k=0)
Tracer transport idealized tracers horizontally homogeneous intialization 3 different tracers: BL tracer (0-1750m) MT tracer (7000-8750m) UT tracer (12250-14000m)
conclusions/perspectives presented a study of idealized tracer transport SLBC necessary for TLSAT important (not included in previous study) chemistry version based on MATCH data from measurements necessary for SLBC use WRF nesting capability comparison with SCM