Large-scale vertical velocity, diabatic heating and drying profiles associated with seasonal and diurnal variations of convective systems observed in the GoAmazon2014/5 experiment

摘要

This study describes the characteristics of large-scale vertical velocity,apparent heating source () and apparent moisture sink() profiles associated with seasonal and diurnal variationsof convective systems observed during the two intensive operational periods(IOPs) that were conducted from 15 February to 26 March 2014 (wet season) andfrom 1 September to 10 October 2014 (dry season) near Manaus, Brazil, duringthe Green Ocean Amazon (GoAmazon2014/5) experiment. The derived large-scalefields have large diurnal variations according to convective activity in theGoAmazon region and the morning profiles show distinct differences betweenthe dry and wet seasons. In the wet season, propagating convective systemsoriginating far from the GoAmazon region are often seen in the early morning,while in the dry season they are rarely observed. Afternoon convectivesystems due to solar heating are frequently seen in both seasons.Accordingly, in the morning, there is strong upward motion and associatedheating and drying throughout the entire troposphere in the wet season, whichis limited to lower levels in the dry season. In the afternoon, both seasonsexhibit weak heating and strong moistening in the boundary layer related tothe vertical convergence of eddy fluxes. A set of case studies of threetypical types of convective systems occurring in Amazonia – i.e.,locally occurring systems, coastal-occurring systems and basin-occurringsystems – is also conducted to investigate the variability of thelarge-scale environment with different types of convective systems.