DOI: 10.1175/JCLI-D-11-00618.1
Scopus记录号: 2-s2.0-84871886156
论文题名: Observations of stratocumulus clouds and their effect on the eastern pacific surface heat budget along 20°S
作者: de Szoeke S.P. ; Yuter S. ; Mechem D. ; Fairall C.W. ; Burleyson C.D. ; Zuidema P.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2012
卷: 25, 期: 24 起始页码: 8542
结束页码: 8567
语种: 英语
Scopus关键词: Atmosphere-ocean interactions
; Clear sky
; Cloud fraction
; Cloud properties
; Cloud radiative forcing
; Cloud vertical structure
; Coupled Model Intercomparison Project
; Diurnal cycle
; Eastern pacific
; Interannual variability
; Local time
; Long-wave radiation
; Precipitation radar
; Radiative cooling
; Radiative forcings
; Stratiform clouds
; Stratocumulus clouds
; Surface heat budget
; Surface radiation
; Tropical Pacific ocean
; Twentieth century
; Atmospheric radiation
; Computer simulation
; Remote sensing
; Sun
; Tropics
; Clouds
; air-sea interaction
; cloud radiative forcing
; heat budget
; remote sensing
; stratiform cloud
; stratocumulus
; Pacific Ocean
英文摘要: Widespread stratocumulus clouds were observed on nine transects from seven research cruises to the southeastern tropical Pacific Ocean along 20°S, 75°-85°W in October-November of 2001-08. The nine transects sample a unique combination of synoptic and interannual variability affecting the clouds; their ensemble diagnoses longitude-vertical sections of the atmosphere, diurnal cycles of cloud properties and drizzle statistics, and the effect of stratocumulus clouds on surface radiation.Mean cloud fraction was 0.88, and 67% of 10-min overhead cloud fraction observations were overcast. Clouds cleared in the afternoon [1500 local time (LT)] to a minimum of fraction of 0.7. Precipitation radar found strong drizzle with reflectivity above 40 dBZ. Cloud-base (CB) heights rise with longitude from 1.0 km at 75°W to 1.2 km at 85°W in the mean, but the slope varies from cruise to cruise. CB-lifting condensation level (LCL) displacement, a measure of decoupling, increases westward. At night CB-LCL is 0-200 m and increases 400 m from dawn to 1600 LT, before collapsing in the evening. Despite zonal gradients in boundary layer and cloud vertical structure, surface radiation and cloud radiative forcing are relatively uniform in longitude. When present, clouds reduce solar radiation by 160 W m-2 and radiate 70 W m-2 more downward longwave radiation than clear skies. Coupled Model Intercomparison Project phase 3 (CMIP3) simulations of the climate of the twentieth century show 40 ± 20 W m-2 too little net cloud radiative cooling at the surface. Simulated clouds have correct radiative forcing when present, but models have ;50% too few clouds. © 2012 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/52127
Appears in Collections: 气候变化事实与影响
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作者单位: College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States; Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC, United States; Atmospheric Science Program, Department of Geography, University of Kansas, Lawrence, KS, United States; NOAA/ESRL/Physical Sciences Division, Boulder, CO, United States; Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States
Recommended Citation:
de Szoeke S.P.,Yuter S.,Mechem D.,et al. Observations of stratocumulus clouds and their effect on the eastern pacific surface heat budget along 20°S[J]. Journal of Climate,2012-01-01,25(24)