Articles | Volume 16, issue 22
Atmos. Chem. Phys., 16, 14249–14264, 2016

Special issue: Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5)...

Atmos. Chem. Phys., 16, 14249–14264, 2016

Research article 16 Nov 2016

Research article | 16 Nov 2016

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

Shuaiqi Tang1, Shaocheng Xie1, Yunyan Zhang1, Minghua Zhang2, Courtney Schumacher3, Hannah Upton3, Michael P. Jensen4, Karen L. Johnson4, Meng Wang4, Maike Ahlgrimm5, Zhe Feng6, Patrick Minnis7, and Mandana Thieman8 Shuaiqi Tang et al.
  • 1Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
  • 2School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA
  • 3Department of Atmospheric Sciences, Texas A&M University, College Station, TX 77843, USA
  • 4Brookhaven National Laboratory, Upton, NY 11973, USA
  • 5European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading RG2 9AX, UK
  • 6Pacific Northwest National Laboratory, Richland, WA 99354, USA
  • 7NASA Langley Research Center, Hampton, VA 23681, USA
  • 8Science Systems and Applications, Inc, Hampton, VA 23666, USA

Abstract. This study describes the characteristics of large-scale vertical velocity, apparent heating source (Q1) and apparent moisture sink (Q2) profiles associated with seasonal and diurnal variations of convective systems observed during the two intensive operational periods (IOPs) that were conducted from 15 February to 26 March 2014 (wet season) and from 1 September to 10 October 2014 (dry season) near Manaus, Brazil, during the Green Ocean Amazon (GoAmazon2014/5) experiment. The derived large-scale fields have large diurnal variations according to convective activity in the GoAmazon region and the morning profiles show distinct differences between the dry and wet seasons. In the wet season, propagating convective systems originating far from the GoAmazon region are often seen in the early morning, while in the dry season they are rarely observed. Afternoon convective systems due to solar heating are frequently seen in both seasons. Accordingly, in the morning, there is strong upward motion and associated heating and drying throughout the entire troposphere in the wet season, which is limited to lower levels in the dry season. In the afternoon, both seasons exhibit weak heating and strong moistening in the boundary layer related to the vertical convergence of eddy fluxes. A set of case studies of three typical types of convective systems occurring in Amazonia – i.e., locally occurring systems, coastal-occurring systems and basin-occurring systems – is also conducted to investigate the variability of the large-scale environment with different types of convective systems.

Short summary
Data observed during the Green Ocean Amazon (GoAmazon2014/5) experiment are used to derive the large-scale fields in this study. The morning propagating convective systems are active during the wet season but rare during the dry season. The afternoon convections are active in both seasons, with heating and moistening in the lower level corresponding to the vertical convergence of eddy fluxes. Case study shows distinguish large-scale environments for three types of convective systems in Amazonia.
Final-revised paper