DOI: 10.1007/s00382-017-3630-0
Scopus记录号: 2-s2.0-85015972559
论文题名: Moisture sources and pathways associated with the spatial variability of seasonal extreme precipitation over Canada
作者: Tan X. ; Gan T.Y. ; Chen Y.D.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 50, 期: 2018-01-02 起始页码: 629
结束页码: 640
语种: 英语
英文关键词: Back-trajectory analyses
; Moisture pathways
; Moisture sources
; Regionalization
; Seasonal extreme precipitation
Scopus关键词: atmospheric moisture
; atmospheric transport
; cluster analysis
; extreme event
; precipitation (climatology)
; regional climate
; regional pattern
; seasonal variation
; spatial variation
; westerly
; Arctic Ocean
; Atlantic Ocean
; Atlantic Ocean (North)
; Canada
; Pacific Ocean
; Pacific Ocean (North)
英文摘要: Nine regions with spatially coherent seasonal 3-day total precipitation extremes across Canada were identified using a clustering method that is compliant to the extreme value theory. Using storm back-trajectory analyses, we then identified possible moisture sources and pathways that are conducive to occurrences of seasonal extreme precipitation events in four seasons for the nine regions identified. Moisture pathways for all extreme precipitation events were clustered to nine dominant moisture pathway patterns using the self-organizing map method. Results show that horizontal moisture pathway patterns and their occurrences were not evidently different between seasons. However, warm (summer and fall) and cold (winter and spring) seasons show considerable differences in the spreading of moisture sources in all nine regions, even though many sources do not frequently contribute to extreme precipitation events. In all four seasons, terrestrial evapotranspiration had provided major moisture sources to many extreme precipitation events occurred in inland regions. Central Canada had received more widespread moisture sources over surrounding oceans of North America than western and eastern Canada, because of more diverse moisture pathway patterns for central Canada that transport moisture from all surrounding oceans to central Canada. Extreme precipitation in southwestern Canada mainly resulted from atmospheric rivers over the North Pacific Ocean. For northwestern Canada, moisture pathway patterns were from the northern Pacific, Arctic and northern Atlantic oceans, even though more than 78% of trajectories for northwestern Canada were from the North Pacific. Westerlies from the North Pacific Ocean and northern polar jet streams controlled dominant pathways to central and eastern Canada. More extreme precipitation events over Canada were fed by the Arctic Ocean in warm than in cold seasons. © 2017, Springer-Verlag Berlin Heidelberg. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109507
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 2W2, Canada; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China; Department of Geography and Resource Management, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Sha Tin, Hong Kong
Recommended Citation:
Tan X.,Gan T.Y.,Chen Y.D.. Moisture sources and pathways associated with the spatial variability of seasonal extreme precipitation over Canada[J]. Climate Dynamics,2018-01-01,50(2018-01-02)