Volume 13, No. 6, December 2013, Pages 1630-1640 PDF(7.62 MB)
Numerical Simulations of Asian Dust-Aerosols and Regional Impact on Weather and Climate- Part I: Control Case-PRCM Simulation without Dust-Aerosols
Wen-Yih Sun1,2, Kate Jr-Shiuan Yang1, Neng-Huei Lin2
1 Department of Earth, Atmospheric and Planetary Sciences, Purdue University, W. Lafayette, IN 47907-2071, USA
2 Department of Atmospheric Sciences, National Central University, Chung-Li, Taiwan
Aerosol particles affect atmospheric radiation and cloud microphysics, and are considered a major uncertainty in climate forcing. At the same time, accurate simulation and prediction of meteorological conditions are necessary to simulate the distribution and chemical reaction of the aerosols. Distribution of pollutions can also be used to validate meteorological models. This paper consists of two parts: Part I: Numerical simulation of weather and soil conditions from the Purdue Regional Climate Model (PRCM); and Part II: Numerical modeling of online interaction between dust and weather/climate. Both parts were integrated continuously from April 08 to 24, 1998 without nudging or restarting. The detailed treatment of soil and the planetary boundary layer (PBL), using the semi-conserved ice-potential temperature and total water substance as prognostic variables, a local reference to calculate the pressure gradient, and the accurate advection scheme, allowed the PRCM to well reproduce the movements of the fronts/cyclones, downslope wind, upper/mid-level-jet, vertical mixing, and the low-level convergence over a complex terrain. They are crucial to the lift, dispersion, and transport of dusts over the Gobi Desert, the Taklimakan Desert, and the downstream regions. The dust model in Part II calculated the production, mixing, transport/removal, and radiative property of the dusts using the meteorology generated by the PRCM. The radiative effects of the dusts calculated from the dust model were then fed back to the PRCM.
Because no nudging or restarting was applied during 17 continuous days of integration, the conservation laws of momentum, energy, and mass (including dry air, water substances and dusts) are valid. Hence, the PRCM provides data that are consistent for studying the movement of aerosols and the interactions among the aerosols, weather, and soil.
Dust; PRCM; Transport; Cutoff low; Jet; Downslope wind.