Search Results

You are looking at 1 - 6 of 6 items for :

  • Cloud forcing x
  • Monthly Weather Review x
  • DYNAMO/CINDY/AMIE/LASP: Processes, Dynamics, and Prediction of MJO Initiation x
  • All content x
Clear All
Eric D. Skyllingstad and Simon P. de Szoeke

active phase of the MJO develops. Fig . 1. Skew T –log p temperature profile (solid) for the average DYNAMO conditions from the R/V Revelle along with a histogram of (a) observed temperature and (b) observed dewpoint temperature. The dashed line signifies the dewpoint temperature used in the model initial conditions. In this study we employ a cloud-resolving large-eddy simulation (LES) model to examine how convection responds to external forcing from prescribed domain-scale moisture convergence

Full access
Xiouhua Fu, Wanqiu Wang, June-Yi Lee, Bin Wang, Kazuyoshi Kikuchi, Jingwei Xu, Juan Li, and Scott Weaver

congestus clouds pop up ( Figs. 8a–c ) due to the forcing of the positive SST anomaly and surface convergence originating from the interaction between the orography over the Maritime Continent and Kelvin wave–induced easterly winds [ Fig. 6 in this manuscript, and Figs. 4 and 5 in Hsu and Lee (2005) ]. These shallow and congestus clouds will not immediately develop into organized deep convection because of the prevalent subsidence induced by the enhanced convection near the array ( Figs. 8a

Full access
Tomoe Nasuno, Tim Li, and Kazuyoshi Kikuchi

: those stressing tropical internal dynamics [e.g., a circumnavigating signal of the previous episode: Lau and Peng (1987) ; Wang and Li (1994) ; Kikuchi and Takayabu (2003) ; Matthews (2008) ; or local processes in the tropics: Hu and Randall (1994) ; Jiang and Li (2005) ; Straub (2013) ] and those emphasizing extratropical forcing (e.g., Hsu et al. 1990 ; Bladé and Hartmann 1993 ; Matthews and Kiladis 1999 ; Pan and Li 2007 ; Lin et al. 2007 ; Ray and Zhang 2010 ; Wang et al. 2012

Full access
Brandon W. Kerns and Shuyi S. Chen

envelope of convection spans ~2000–4000 km and is often organized into coherent “super cloud clusters,” which can be objectively tracked for several days ( Nakazawa 1988 ; Mapes and Houze 1993 ; Chen et al. 1996 ). In addition to convection, the low- (upper-) level winds oscillate between anomalous easterlies (westerlies) and westerlies (easterlies) with the passage of the MJO. Because of its global influence on general circulation patterns, the MJO affects floods ( Bond and Vecchi 2003 ), droughts

Full access
Jean-Philippe Duvel

this stage, however, it is difficult to consider the MJO modulation of the PV gradient as a pure forcing. The presence of more TDs in active phases may also influences the PV gradient and may explain part of the gradient reduction, especially for phases 5 and 6. Other aspects of the MJO influence are discussed below. As noted above, the strengthening of the meridional shear of the zonal wind results from a reinforcement of both westerlies to the north and easterlies to the south. Westerlies near

Full access
George N. Kiladis, Juliana Dias, Katherine H. Straub, Matthew C. Wheeler, Stefan N. Tulich, Kazuyoshi Kikuchi, Klaus M. Weickmann, and Michael J. Ventrice

13 , the fact that the RMM amplitude may at times be weak even with the presence of an “MJO like” convective signal, or strong in the absence of such a signal, raises the question of which fundamental characteristics of the MJO should be used to define it. While we will not directly address this issue here, we point out that the essential circulation features of MJO teleconnections in both the tropics and extratropics can be reproduced in a dry primitive equation model by forcing associated with

Full access