Impacts of Land–Atmosphere Feedbacks on Deep, Moist Convection on the Canadian Prairies

Earth Interactions

Julian C.Brimelow¹ 

关键词: Thunderstorm;    Prairie;    Feedback;   

DOI  :  10.1175/2011EI407.1

学科分类：地球科学(综合)

来源: American Geophysical Union

【 摘 要 】

AbstractThe purpose of this study was to focus on how anomalies in the normalized difference vegetation index (NDVI; a proxy for soil moisture) over the Canadian Prairies can condition the convective boundary layer (CBL) so as to inhibit or facilitate thunderstorm activity while also considering the role of synoptic-scale forcing. This study focused on a census agricultural region (CAR) over central Alberta for which we had observed lightning data (proxy for thunderstorms), remotely sensed NDVI data, and in situ rawinsonde data (to quantify impacts of vegetation vigor on the CBL characteristics) for 11 summers from 1999 to 2009. The authors’ data suggest that the occurrence of lightning over the study area is more likely (and is of longer duration) when storms develop in an environment in which the surface and upper-air synoptic-scale forcing are synchronized. On days when surface forcing and midtropospheric ascent are present, storms are more likely to be triggered when NDVI is much above average, compar...

【 授权许可】

Unknown