Influence of the Frontal Systems on the Day-to-Day Convection Variability over South America
Influence of the Frontal Systems on the Day-to-Day Convection Variability over South America
复制标题
锋面系统对南美洲日常对流变化的影响
DOI：
--
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
L. Machado
中科院分区：
文献类型：
--
作者：
J. Siqueira;L. Machado
摘要利用国际卫星云气候学计划图像和纬度-时间图获取的冷云顶分量，研究了南美（SA）上空锋面系统与热带对流的相互作用。建立了锋面系统-热带对流相互作用的三种频繁类型的11年气候学，并利用卫星图像、复杂主成分和小波变换描述了相关的逐日对流变率。第1型全年频繁发生，尤其是在南方夏季，其特征是副热带南亚冷锋的渗透与热带对流相互作用并随其移动到热带低纬度地区。第2型在南方夏季也更为频繁，其特征是亚马逊对流和沿副热带冷锋通道从亚马逊盆地延伸到副热带南亚的准静止西北-东南方向对流带的增强。当2型模式…
Abstract Cold cloud-top fractions derived from International Satellite Cloud Climatology Project images and latitude– time diagrams are used to study the interaction of frontal systems with tropical convection over South America (SA). An 11-yr climatology for three frequent types of frontal system–tropical convection interaction is built, and the associated day-to-day convection variability is described using satellite images, complex principal components, and wavelet transforms. Type 1 is frequent throughout the year, especially in austral summer, and is characterized by the penetration of a cold front in subtropical SA that interacts with tropical convection and moves with it into lower tropical latitudes. Type 2 is also more frequent in austral summer and is characterized by Amazon convection and enhancement of a quasi-stationary northwest–southeast-oriented band of convection extending from the Amazon basin to subtropical SA along the passage of a cold front in the subtropics. When the type 2 pattern ...