DOI: 10.1175/JCLI-D-16-0749.1
Scopus记录号: 2-s2.0-85019061729
论文题名: An anomalous genesis potential index for MJO modulation of tropical cyclones
作者: Wang B. ; Moon J.-Y.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2017
卷: 30, 期: 11 起始页码: 4021
结束页码: 4035
语种: 英语
Scopus关键词: Climate change
; Hurricanes
; Mechanical waves
; Modulation
; Storms
; Tropics
; Vorticity
; Different time scale
; Eastward propagation
; General circulation model
; Intraseasonal variability
; Intraseasonal variations
; Madden-Julian oscillation
; Southern indian ocean
; Tropical cyclone
; Climatology
英文摘要: Modulation of tropical cyclone (TC) genesis by the Madden-Julian oscillation (MJO) has been quantitatively diagnosed by using a climatological genesis potential index (GPI). Analysis of TC genesis during November-April of 1979-2014 indicates the most effective factors controlling intraseasonal TC genesis are 850-hPa relative vorticity weighted by the Coriolis parameter fζr850 and 500-hPa vertical motion ω500. The total vertical wind shear and maximum potential intensity are unimportant, and the role of 600-hPa relative humidity is greatly represented by ω500. The MJO modulates TC genesis primarily through changing low-level vorticity induced by its Rossby wave gyres and meridional shears of equatorial zonal winds. A new intraseasonal GPI (ISGPI) is proposed to quantify the MJO's modulation of TC genesis. The ISGPI significantly improves representation of intraseasonal variation of TC genesis in the tropics and in each subregion of the southern Indian Ocean, Australian monsoon, and South Pacific. In the hot spots of the Southern Hemisphere TC genesis zone, the probability of TC genesis can differ by a factor of 5-19 as a result of MJO modulation. The results suggest that the large-scale factors controlling TC genesis may vary with different time scales, and the climatological GPI may not be quite applicable for diagnoses of climate variability and future change of TC genesis potential. To simulate realistic impacts of the MJO on TC genesis, general circulation models must reproduce not only realistic eastward propagation but also the MJO low-level circulation structure. Application of the new ISGPI may have a large potential to improve dynamical subseasonal prediction of TC genesis. © 2017 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/48884
Appears in Collections: 气候变化与战略
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作者单位: Department of Atmospheric Sciences, International Pacific Research Center, University of Hawai'i at Manoa, Honolulu, HI, United States; Atmosphere-Ocean Research Center, University of Hawai'i at Manoa, Honolulu, HI, United States; Earth System Modeling Center, Nanjing University of Information Science and Technology, Nanjing, China
Recommended Citation:
Wang B.,Moon J.-Y.. An anomalous genesis potential index for MJO modulation of tropical cyclones[J]. Journal of Climate,2017-01-01,30(11)