Experiments with a Spectral Convection Model

波譜對流模式的數值實驗

郭鴻基(Hung-Chi Kuo) ； 鄭兆尊(Chao-Tzuen Cheng)

《Terrestrial, Atmospheric and Oceanic Sciences》 10卷4期 (1999/12) Pp. 651-692

並列摘要

In this study,we use a simple and semi-quantitative scheme to estimatethe contribution(denoted as f)of below-cloud scavenging of pollutants byraindrops,based on the precipitation chemistry collected in Taipei Cityand the cloud chemistry observed at the peak of the Mt.Bamboo(around1100m MSL)in the winters of 1996-1998.The magnitudes of f(nss(non-sea salt)-SO(superscript 2-)4),f(NO(superscript -)3)and f(NH(superscript +)4)were estimated to range between 0.31-0.88,0.25-0.88 and 0.54-96,respectively.For instance,54-96% of the NH(superscript +)4ions in rainwater arose by below-cloud scavenging,reflecting their originsfrom local sources.For most of the cases,at least 75% of the NO(superscript -)3 wasaccounted for by the same scavenging mechanism,whereas more than 25%of nss-SO(superscript 2-)4 resulted from in-cloud scavenging.In comparison with NH(superscript +)4and NO(superscript -)3,relatively higher amounts of nss-SO(superscript 2-)4 obviously derived fromlong-range transport.

並列關鍵字

Fourier-Chebyshev Spectral Method ； Acoustic Adjustment ； Lanczos Filter