The Mechanism for the Scale Selection of Tropical Intraseasonal Oscillations. Part I: Selection of Wavenumber 1 and the Three-Scale Structure

摘要: Abstract The mechanism for the scale selection of tropical intraseasonal oscillations (ISO) is examined in a stepwise procedure with use two models, which differ only cumulus parameterization. In first model, moisture budgets are treated explicitly. Using this ISO wavenumber 1 pattern successfully reproduced and some possible causes responsible can be specified. second model does not employ convection related to low-level convergence only. obtained by parameterized implemented or eliminated from clarify property an essential selection. order that selected, must formed over large having convergence, but confined narrow regions. This realized limiting areas wet regions, preventing weak low...