HR: 08:30h
AN: A11D-03    [PDF]
TI: Impacts of numerical approximation in atmospheric tracer transport: examples from the Global Modeling Initiative
AU: * Prather, M J
EM: mprather@uci.edu
AF: Earth System Science Dept, UC Irvine, Irvine, CA 92697-3100
AU: Zhu, X
EM: XZhu@halo.ps.uci.edu
AF: Earth System Science Dept, UC Irvine, Irvine, CA 92697-3100
AB: Improved numerical methods for transport of trace species in the atmosphere and ocean continue to be developed. Typically, these algorithms are evaluated against existing methods using analytic or idealized test cases, but the NASA Global Modeling Initiative now provides a realistic framework for evaluating their accuracy in full chemistry-transport models (CTM). GMI's modular approach is combined with parallel simulations in the UCI CTM to quantify the differences between two relatively accurate tracer transport algorithms (Lin-Rood, Prather 2nd-order moments), including the impact of forcing a positive-definite, ripple-free tracer abundance. We use a range of simplified atmospheric chemical tracers (radon-lead, fossil-fuel CO2, industrial and biomass CO) with the meteorology from the Goddard Institute for Space Studies global climate model (4 deg by 5 deg with 23 layers) that includes three-hourly integrated winds, boundary-layer physics, entraining and non-entraining convection, large-scale and convective precipitation, updrafts and downdrafts. The relative accuracy of the different methods is considered in terms of forward and inverse calculations. We thank the entire GMI team, especially the researchers at LLNL and GSFC who have built and maintained the GMI modeling capability.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0322 Constituent sources and sinks
DE: 0341 Middle atmosphere--constituent transport and chemistry (3334)
DE: 3230 Numerical solutions
DE: 3337 Numerical modeling and data assimilation
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting