Simulation on Chemistry Tracer Transportation and Concentration in Extremely High ABL Environment in Northwest China

Abstract

Extremely high atmospheric boundary layer is observed over the arid area in Northwest China during late spring and early summer in 2000. By using the community mesoscale weather research and forecasting/Atmospheric Chemistry model (WRF-Chem), numerical simulation is performed to study chemistry tracer diffusion in the extremely high atmospheric boundary layer. Results show that the extremely high atmospheric boundary layer has great influence on the chemistry tracer transportation. The influence is more effective than that driven by wind which is limited by the local terrain. The tracer is controlled in low-level concentration during the daytime but increases rapidly during the nighttime. Sensitive experiments are performed by disturbing soil moisture and albedo to further investigate surface forcing on the atmospheric boundary layer height and the chemistry tracer concentration. It shows that soil moisture or albedo is disturbed as increasing makes the tracer concentration increase in low layer for response of ABL height decrease.