DOI: 10.1002/joc.5731
论文题名: The impact of Arctic sea ice on the inter-annual variations of summer Ural blocking
作者: Zhang R. ; Sun C. ; Zhang R. ; Jia L. ; Li W.
刊名: International Journal of Climatology
ISSN: 8998418
出版年: 2018
卷: 38, 期: 12 起始页码: 4632
结束页码: 4650
语种: 英语
英文关键词: Arctic sea ice
; inter-annual variations
; numerical simulations
; soil moisture
; Ural blocking frequency
Scopus关键词: Computer simulation
; Heat flux
; Soil moisture
; Thickness gages
; Troposphere
; Anticyclonic circulation
; Arctic sea ice
; Atmospheric baroclinicity
; Background conditions
; Community atmospheric model
; Interannual variation
; Meridional temperature gradient
; Ural blocking frequency
; Sea ice
; annual variation
; atmosphere-ice-ocean system
; atmospheric blocking
; atmospheric modeling
; meridional circulation
; numerical method
; precipitation (climatology)
; sea ice
; soil moisture
; summer
; temperature gradient
; thermodynamics
; zonal wind
; Arctic Ocean
; Barents Sea
; Urals
英文摘要: The influence of Arctic sea ice concentration (SIC) on the inter-annual variations of the frequency of summertime Ural blocking (UB) during the period of 1980–2013 is investigated using observational and reanalysis data sets and version 5.0 of the Community Atmospheric Model. The results reveal that the variations in the UB frequency display a statistically significant association with a persistent spring–summer SIC pattern in the Barents Sea. Related to high UB frequencies, heavy SICs exert a dynamic influence by increasing the meridional temperature gradient (MTG) in the lower troposphere and cause stronger (weaker) zonal winds in high-latitude (mid-latitude) areas through the thermal wind balance. This zonal wind pattern establishes the background conditions for the blocking activity and thus helps to initiate summertime UB events. Moreover, persistent heavy SICs tend to enhance the low-level atmospheric baroclinicity to the south and decreases in mid-latitude areas, inducing weakened synoptic-scale transient eddy activity (STEA) that stretches from eastern Europe to the Ural Mountains. This reduced STEA is accompanied by a locally intensified eddy-vorticity forcing that may exert a downstream influence on the onset of UB events. In terms of thermodynamic processes, heavy SICs-induced water vapour content anomalies are expected to cause deficits in precipitation over the East European Plateau in late spring and subsequently desiccate the underlying soil. Both of these effects are expected to increase surface heat fluxes and thickness of the lower-middle troposphere, thus favouring anomalous anticyclonic circulation over the Ural Mountains. On the other hand, the opposite dynamic and thermodynamic effects are expected to result from light SICs with respect to low UB frequencies. Therefore, these two effects identified in this study each contribute to an increased probability of more frequent (rare) UB events in summer as the spring–summer sea ice within the regions surrounding the Barents Sea expands (disappears). © 2018 The Authors. International Journal of Climatology published by John Wiley & Sons Ltd on behalf of the Royal Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/116783
Appears in Collections: 气候减缓与适应
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作者单位: Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China; National Meteorological Information Center, China Meteorological Administration, Beijing, China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing, China; NOAA Climate Prediction Center/Innovim LLC, College Park, MD, United States; National Climate Center, China Meteorological Administration, Beijing, China
Recommended Citation:
Zhang R.,Sun C.,Zhang R.,et al. The impact of Arctic sea ice on the inter-annual variations of summer Ural blocking[J]. International Journal of Climatology,2018-01-01,38(12)