Flow and pollution transport during Wagerup 2006: a case study

Meteorological applications

article

Charles Retallack¹  Ron Calhoun¹  H. J. S. Fernando¹  Ken Rayner³  Anthony Stuart³  John Sutton³  Mark F. Hibberd⁴ 

[1] Department of Mechanical and Aerospace Engineering, Arizona State University;Mechanical and Aerospace Engineering, Arizona State University, Main Campus;Department of Environment and Conservation;Marine and Atmospheric Research

关键词: pollution transport;    stratified flow;    shear induced mixing;    topographic influences;    Doppler lidar;   

DOI  :  10.1002/met.161

学科分类：社会科学、人文和艺术（综合）

来源: Wiley

【 摘 要 】

As part of a broader field campaign dubbed Wagerup 2006, a case study was carried out to determine the overnight pollution transport mechanisms and flow characteristics near Wagerup, Western Australia. The ambient conditions were characterized by stable stratification with little synoptic influence in the lower boundary layer. An elevated jet intrusion originating on a nearby escarpment slope was found to induce sufficient mixing causing elevated pollution plumes to reach ground level. Onset of mixing was accurately predicted by non-linear critical Richardson number estimates obtained in previous laboratory work. The increase in ground level temperatures brought about by shear induced mixing later prompted a sea-breeze like gravity current that was completely blocked by the escarpment and as a result pollutants were trapped against the escarpment slope. A notable side effect of the topographic blocking was the subsequent steady 360° rotation of ground level winds within an area of influence described by the Rossby deformation radius.

【 授权许可】

CC BY|CC BY-NC|CC BY-NC-ND