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Advances in Atmospheric Sciences 2009年第3期26卷 577-584页

作者：张占海周明煜 Sharon ZHONG donald H. lenschow Qing WANG Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 Department of Geography Michigan State University East LansingMI 48824-111USA National Center for Atmospheric Research BoulderCO 80307USA Department of Meteorology Naval Postgraduate SchoolMontereyCA 93943USA

A set of new parameterizations for the friction velocity and temperature scale over gently sloped terrain and in calm synoptic conditions are theoretically derived. The friction velocity is found to be proportional to the product of the square root of the total accumulated heating in the boundary layer and the sinusoidal function of the slope angle, while the temperature scale is proportional to the product of the boundary layer depth, the sinusoidal function of the slope angle and the potential temperature gradient in the free atmosphere. Using the new friction velocity parameterization, together with a parameterization of eddy diffusivity and an initial potential temperature profile around sunrise, an improved parameterization for the thermally induced upslope flow profile is derived by solving the Prandtl equations. The upslope flow profile is found to be simply proportional to the friction velocity.

关键词： friction velocity temperature scale slope terrain flux-profile relationship upslope flow

Analysis of Boundary Layer Structure,Turbulence,and Flux Variations before and after the Passage of a Sea Breeze Front Using Meteorological Tower Data

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Journal of Meteorological Research 2023年第6期37卷 855-877页

作者： Ju LI Junxia DOU donald H. lenschow Mingyu ZHOU Lihong MENG Xiaobin QIU Yubing PAN Jingjiang ZHANG Institute of Urban Meteorology(Key Laboratory of Urban Meteorology) China Meteorological AdministrationBeijing100089China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Beijing Research Center for Urban Meteorological Engineering and Technology Beijing100081China National Center for Atmospheric Research BoulderCO80307USA National Marine Environmental Prediction Center Beijing100081China Tianjin Key Laboratory for Oceanic Meteorology Tianjin300074China Tianjin Institute of Meteorological Science Tianjin300074China

A detailed analysis of a sea breeze front(SBF)that penetrated inland in the Beijing–Tianjin–Hebei urban agglomeration of China was *** focused on the boundary layer structure,turbulence intensity,and fluxes before and after the SBF passed through two meteorological towers in the urban areas of Tianjin and Beijing,*** changes in temperature,humidity,winds,CO_(2),and aerosol concentrations were observed as the SBF *** in these changes at the two towers mainly resulted from their distances from the ocean,boundary layer conditions,and background *** the SBF approached,a strong updraft appeared in the boundary layer,carrying near-surface aerosols aloft and forming the SBF *** was followed by a broad downdraft,which destroyed the near-surface inversion layer and temporarily increased the surface air temperature at *** feeder flow after the thermodynamic front was characterized by low-level jets horizontally,and downdrafts and occasional updrafts *** increased significantly during the SBF’s passage,causing an increase in the standard deviation of wind components in *** increase in turbulence was more pronounced in a stable boundary layer compared to that in a convective boundary *** passage of the SBF generated more mechanical turbulences,as indicated by increased friction velocity and turbulent kinetic energy(TKE).The shear term in the TKE budget equation increased more significantly than the buoyancy *** atmosphere shifted to a forced convective state after the SBF’s passage,with near isotropic turbulences and uniform mixing and diffusion of *** heat fluxes(latent heat and CO_(2)fluxes)showed positive(negative)peaks after the SBF’s passage,primarily caused by horizontal and vertical transport of heat(water vapor and CO_(2))during its *** study enhances understanding of boundary layer changes,turbulences,and fluxes during the passage of SBFs over u

关键词： sea breeze front boundary layer structure turbulence flux meteorological tower

Validation of ECMWF and NCEP–NCAR Reanalysis Data in Antarctica

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Advances in Atmospheric Sciences 2010年第5期27卷 1151-1168页

作者：于乐江张占海周明煜 Shiyuan ZHONG donald lenschow Hsiaoming HSU 吴辉碇孙波 Polar Research Institute of China Shanghai 200136 Department of Geography Michigan State University East Lansing MI 48824-111 USA National Center for Atmospheric Research Boulder CO 80307 USA National Marine Environmental Forecast Center Beijing 100081

The European Center for Medium-Range Weather Forecast （ECMWF） Re-Analysis （ERA-40） and the National Centers for Environmental Prediction-National Center for Atmospheric Research （NCEP-NCAR） ECMWF （ERA-40） and NCEP–NCAR reanalysis data were compared with Antarctic station observations, including surface-layer and upper-layer atmospheric observations, on intraseasonal and interannual timescales. At the interannual timescale, atmospheric pressure at different height levels in the ERA-40 data are in better agreement with observed pressure than that in the NCEP–NCAR reanalysis data. ERA-40 reanalysis also outperforms NCEP–NCAR reanalysis in atmospheric temperature, except in the surface layer where the biases are somewhat larger. The wind velocity fields in both datasets do not agree well with surface-and upper-layer atmospheric observations. At intraseasonal timescales, both datasets capture the observed intraseasonal variability in pressure and temperature during austral winter.

关键词： reanalysis data interannual variability intraseasonal variability surface layer upper layer Antarctica

The variability of surface radiation fluxes over landfast sea ice near Zhongshan station,east Antarctica during austral spring

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International Journal of Digital Earth 2019年第8期12卷 860-877页

作者： Lejiang Yu Qinghua Yang Mingyu Zhou donald H.lenschow Xianqiao Wang Jiechen Zhao Qizhen Sun Zhongxiang Tian Hui Shen Lin Zhang State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of ChinaShanghaiPeople’s Republic of China Key Laboratory of Research on Marine Hazards Forecasting National Marine Environment Forecasting CenterBeijingPeople’s Republic of China National Center for Atmospheric Research BoulderCOUSA

Surface radiative fluxes over landfast sea ice off Zhongshan station have been measured in austral spring for five springs between 2010 and *** and upward solar radiation vary diurnally with maximum amplitudes of 473 and 290 W m^(−2),*** maximum and minimum long-wave radiation values of the mean diurnal cycle are 218 and 210 W m^(−2)for downward radiation,277 and 259 W m^(−2)for upward radiation and 125 and−52 W m^(−2)for net *** albedo has a U-shaped mean diurnal cycle with a minimum of 0.64 at *** ice thickness is in the growth phase for most spring days,but can be disturbed by synoptic *** surface temperature largely determines the occurrence of ice *** downward and upward long-wave radiation show synoptic oscillations with a 5–8 day period and intraseasonal variability with a 12–45 day *** amplitudes of the diurnal,synoptic and intraseasonal variability show some differences during the five austral springs considered *** intraseasonal and synoptic variability of downward and upward long-wave radiation are associated with the variability of cloud cover and surface temperature induced by the atmospheric circulation.

关键词： Surface radiation flux Antarctic sea ice diurnal cycle synoptic and intraseasonal variability el niño southern oscillation(ENSO)

The scalar gradient near the top of the convective boundary layer

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Acta Oceanologica Sinica 1988年第S1期 132-139页

作者： donald H. lenschow,B. Boba Stankov National Center for Atmospheric Research P.O. Box 3000 Boulder CO 80307 U.S.A. Wave Propagation Laboratory ERL NOAA Boulder CO 80303 U.S.A.

-The fiux-gradient relationship for temperature in the unstably statified atmospheric surface layer is well established, and seems to apply also to other scalars, such as humidity. Throughout the rest of the boundary layer, however, a flux-gradient relationship based on a flux at the surface is not well defined if a significant entrainment flux exists at the boundary-layer top. Wyngaard (see Wyngaard and Brost, 1984; Moeng and Wyngaard, 1984) has developed a model which assumes that a flux-gradient relationship can be defined separately for bottom-up transport due to a flux at the surface, and for top-down transport due to a flux through the boundary-layer top. He has shown, by means of large-eddy numerical simulations, that the model can successfully predict the flux-gradient relationship for scalars throughout most of the boundary layer. We have used aircraft profile measurements of temperature, humidity, and ozone concentration near the top of the boundary layer, and aircraft vertical flux measuremen

关键词： The scalar gradient near the top of the convective boundary layer

Trends in Latent and Sensible Heat Fluxes over the Southern Ocean

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Atmospheric and Climate Sciences 2012年第2期2卷 159-173页

作者： Lejiang Yu Zhanhai Zhang Mingyu Zhou Shiyuan Zhong donald H.lenschow Binrui Li Xianqiao Wang Shiming Li Huiding Wu Bo Sun Applied Hydrometeorological Research Institute Nanjing University of Information Science&TechnologyNanjingChina Polar Research Institute of China ShanghaiChina National Marine Environment Forecast Center BeijingChina Michigan State University East LansingUSA National Center for Atmospheric Research BoulderUSA

In this study, the trends in latent and sensible heat fluxes (LHF and SHF) over the Southern Ocean (oceans south of 35?S) and the contributions of the Antarctic Oscillation (AAO), the Pacific-South America teleconnection patterns (PSA1 and PSA2) and The El Ni?o-Southern Oscillation (ENSO) to these heat fluxes were investigated using the Objectively Analyzed Air-Sea Fluxes (OAFlux) dataset from 1979 to 2008. Significant positive annual trends in LHF occur over the Agulhas Current, the Brazil Current, the oceans in the vicinity of New Zealand and southern Australia, and the eastern Pacific Ocean near between 35?S and 40?S. Significant negative seasonal trends occur in LHF which differ among the four seasons. The spatial pattern and seasonal variation of the trends in SHF over the Southern Ocean are similar to those of LHF. The spatial patterns of the trends in LHF and SHF caused by the AAO, PSA1, PSA2 and Southern Oscillation Index (SOI) indices show a wave-like feature, varying with different seasons, that can be explained by the anomalous meridional wind associated with the four indices. The above four indices account for a small portion of the trend in LHF and SHF. The residual trends in LHF over the Southern Ocean may be explained by a climate shift in the late 1990s for the four seasons. But the residual trends in SHF over the Southern Ocean are not associated with the climate shift.

关键词： Southern Ocean Antarctic Oscillation Pacific-South America Teleconnection El Nino-Southern Oscillation Heat Flux

Challenges and Opportunities in Urban Meteorology Research and Forecast

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Science Foundation in China 2005年第1期13卷 23-30页

作者： Wang Yingchun Li Ju Chen Fei lenschow donald Sun Jielun Niyogi Dev Lau Kaihon Jiang Weimei Ding Guoan Wu Dui Institute of Urban Meteorology Beijing 100089 National Center for Atmospheric Research Boulder USA Purdue University West Lafayette USA Hong Kong University of Science and Technollogy Hlong Kong China Nanjing University Nanjing 210008 Chinese Academy of Meteorological Studies Beijing 100081 Institute of Tropical and Marine Meteorology Guang Zhou 510080

An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology （ China ） and the National Center for Atmospheric Research （US） in Beijing, October, 2004. The workshop was intended to share recent progress in urban meteorological research, discuss issues related to research and development priorities faced by diverse Chinese institutions, and explore collaboration opportunities between Chinese and US research institutions. This article summarizes the major issues discussed at the workshop, including observation on urban boundary layer, urban landuse modeling, socio-economic impacts of weather and climates, and air quality in urban environment. It includes recommendations for future urban meteorology observational and modeling research, and potential collaborative opportunities between China and US.

关键词： urban meteorology urban boundary layer observation landuse urban modeling socio economic impacts air quality

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第2章大气观测系统100年进步

气象科技进展 2019年第S1期9卷 18-39页

作者：杰弗里·斯蒂斯 DARREL BAUMGARDNER JULIE HAGGERTY R.MICHAEL HARDESTY WEN-CHAU LEE donald lenschow PETER PILEWSKIE PAUL L.SMITH MATTHIAS STEINER HOLGER V?MEL 贾朋群李婧华 NCAR 微滴测量科技公司科罗拉多大学 NOAA/ESRL 南达科他矿业理工学院

虽然在美国气象学会于1919年成立之前,大气观测系统已经是气象的重要组成部分,过去的100年里,无论是观测的数量还是种类都获得了稳定增加。本文给出了观测系统研发的案例,诠释这些系统如何促成了科学发现。这些案例包括了与边界层、高... 详细信息

虽然在美国气象学会于1919年成立之前,大气观测系统已经是气象的重要组成部分,过去的100年里,无论是观测的数量还是种类都获得了稳定增加。本文给出了观测系统研发的案例,诠释这些系统如何促成了科学发现。这些案例包括了与边界层、高空、云和降水以及太阳和地球辐射相关的观测系统。对应用广泛的特殊观测系统,例如雷达、光达和研究用飞机等进行了讨论,并给出在天气和气候预报中应用的个例。这些个例中还包含了臭氧和二氧化碳等特殊的化学观测。观测系统的信息源,包括本文集其他章节涉及内容,也进行了讨论。过去100年大气观测系统的特征,是社会对天气观测的需求与大气过程基本气象研究需求之间的协同。在后半程里,观测系统的改进得到数值模式对更高分辨率数据、长期观测和更好的全球覆盖等不断增长需求的推进。这也带来数据获取和获得来自不断增加的各种观测系统类型和观测网的融合数据的需求,这样的趋势或将持续。

关键词：观测系统美国气象学会气象研究地球辐射全球覆盖天气观测长期观测信息源

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第9章边界层气象学100年进步

气象科技进展 2019年第S1期9卷 123-143页

作者：玛格丽特·雷蒙 WAYNE M.ANGEVINE CHRISTOPHER S.BRETHERTON FEI CHEN JIMY DUDHIA EVGENI FEDOROVICH KRISTINA B.KATSAROS donald H.lenschow LARRY MAHRT EDWARD G.PATTON JIELUN SUN MICHAEL TJERNSTR?M JEFFREY WEIL 李婧华贾朋群 NCAR 美国科罗拉多大学 NOAA ESRL 美国华盛顿大学美国俄克拉何马大学美国西北研究协会瑞典斯德哥尔摩大学

在过去的100年里,边界层气象学从以近地面观测为主的学科,发展为涵盖全球各种大气边界层(ABL)的领域。从一开始,研究人员就从不断扩展的学科--热力学、土壤和植物研究、流体动力学和湍流、云微物理学和气溶胶等汲取经验。为了研究颗粒... 详细信息

在过去的100年里,边界层气象学从以近地面观测为主的学科,发展为涵盖全球各种大气边界层(ABL)的领域。从一开始,研究人员就从不断扩展的学科--热力学、土壤和植物研究、流体动力学和湍流、云微物理学和气溶胶等汲取经验。为了研究颗粒物和痕量气体的扩散,研究范围向上扩大到包括整个ABL,之后研究延伸到在数值天气气候模式表征ABL(从1970-1980年代开始),并利用其他领域的发展带来的机会,包括大涡模拟(1970年代)、直接数值模拟(1990年代)和从地面、大气和空间中对边界层进行外场和远程采样的仪器。1940-1970年代,近地面通量廓线关系研究迅速发展,当时迅速发展的领域转向了晴朗天气对流边界层(CBL),尽管热带CBL研究可以追溯到1940年代。1980年代,ABL研究开始包括ABL与地面和云的相互作用,并出现了第一个ABL参数化方案;陆面和海面模式也蓬勃发展。随后几十年中,研究侧重于因天气气候模式的缺陷或不确定性而发现的更为复杂的ABL,包括稳定边界层、北极边界层、阴天边界层和非均匀地面(包括城市)上的ABL。最后进行了简要概述,总结了一些经验教训,并展望了未来。

关键词：天气气候对流边界层直接数值模拟痕量气体流体动力学稳定边界层参数化方案经验教训