DOI: 10.1175/JCLI-D-18-0240.1
Scopus记录号: 2-s2.0-85061010381
论文题名: Phase locking of the boreal summer atmospheric response to dry land surface anomalies in the Northern Hemisphere
作者: Wang H. ; Schubert S.D. ; Koster R.D. ; Chang Y.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2019
卷: 32, 期: 4 起始页码: 1081
结束页码: 1099
语种: 英语
英文关键词: Atmosphere-land interaction
; Drought
; Rossby waves
; Stationary waves
; Summer/warm season
; Topographic effects
Scopus关键词: Drought
; Mechanical waves
; Soil moisture
; Troposphere
; Atmosphere-land interactions
; Rossby wave
; Stationary waves
; Summer/warm season
; Topographic effects
; Locks (fasteners)
英文摘要: Past modeling simulations, supported by observational composites, indicate that during boreal summer, dry soil moisture anomalies in very different locations within the U.S. continental interior tend to induce the same upper-tropospheric circulation pattern: a high anomaly forms over west-central North America and a low anomaly forms to the east. The present study investigates the causes of this apparent phase locking of the upper-level circulation response and extends the investigation to other land regions in the Northern Hemisphere. The phase locking over North America is found to be induced by zonal asymmetries in the local basic state originating from North American orography. Specifically, orography-induced zonal variations of air temperature, those in the lower troposphere in particular, and surface pressure play a dominant role in placing the soil moisture-forced negative Rossby wave source (dominated by upper-level divergence anomalies) over the eastern leeside of the Western Cordillera, which subsequently produces an upper-level high anomaly over west-central North America, with the downstream anomalous circulation responses phase locked by continuity. The zonal variations of the local climatological atmospheric circulation, manifested as a climatological high over central North America, help shape the spatial pattern of the upper-level circulation responses. Considering the rest of the Northern Hemisphere, the northern Middle East exhibits similar phase locking, also induced by local orography. The Middle Eastern phase locking, however, is not as pronounced as that over North America; North America is where soil moisture anomalies have the greatest impact on the uppertropospheric circulation. © 2019 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/117206
Appears in Collections: 气候变化与战略
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Recommended Citation:
Wang H.,Schubert S.D.,Koster R.D.,et al. Phase locking of the boreal summer atmospheric response to dry land surface anomalies in the Northern Hemisphere[J]. Journal of Climate,2019-01-01,32(4)