DOI: 10.1175/JCLI-D-19-0342.1
论文题名: Role of maritime continent land convection on the mean state and MJO propagation
作者: Ahn M.-S. ; Kim D. ; Ham Y.-G. ; Park S.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2020
卷: 33, 期: 5 语种: 英语
Scopus关键词: Budget control
; Climate models
; Moisture
; Eastward propagation
; Global climate model
; Madden-Julian oscillation
; Maritime Continent
; Moist static energy
; Moisture distribution
; Moisture gradient
; Propagation characteristics
; Climatology
; atmospheric convection
; experimental study
; Madden-Julian oscillation
; meridional circulation
; sensitivity analysis
; three-dimensional modeling
; wave propagation
; Indian Ocean
英文摘要: The Maritime Continent (MC) region is known as a "barrier" in the life cycle of the Madden-Julian oscillation (MJO). During boreal winter, the MJO detours the equatorial MC land region southward and propagates through the oceanic region. Also, about half of the MJOevents that initiate over the Indian Ocean cease around the MC. The mechanism through which the MC affects MJO propagation, however, has remained unanswered. The current study investigates the MJO-MC interaction with a particular focus on the role of MC land convection. Using a global climate model that simulates both mean climate and MJO realistically, we performed two sensitivity experiments in which updraft plume radius is set to its maximum and minimum value only in the MC land grid points, making convective top deeper and shallower, respectively. Our results show that MC land convection plays a key role in shaping the 3D climatological moisture distribution around the MC through its local and nonlocal effects. Shallower and weaker MC land convection results in a steepening of the vertical and meridional mean moisture gradient over the MC region. The opposite is the case whenMCland convection becomes deeper and stronger. The MJO's eastward propagation is enhanced (suppressed) with the steeper (lower) mean moisture gradient. The moist static energy (MSE) budget of theMJOreveals the vertical and meridional advection of the meanMSE by MJOwind anomalies as the key processes that are responsible for the changes in MJO propagation characteristics. Our results pinpoint the critical role of the background moisture gradient on MJO propagation. © 2020 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/159005
Appears in Collections: 气候变化与战略
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作者单位: Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States; Department of Oceanography, Chonnam National University, Gwangju, South Korea; School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea
Recommended Citation:
Ahn M.-S.,Kim D.,Ham Y.-G.,et al. Role of maritime continent land convection on the mean state and MJO propagation[J]. Journal of Climate,2020-01-01,33(5)