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1.
J.-F. Miao D. Chen K. Wyser K. Borne J. Lindgren M. K. S. Strandevall S. Thorsson C. Achberger E. Almkvist 《Meteorology and Atmospheric Physics》2008,99(1-2):77-103
Summary The performance of MM5 mesoscale model (Version 3.6.3) using different planetary boundary layer (PBL) and land surface model
(LSM) parameterizations is evaluated and compared using high temporal and spatial resolution G?TE2001 campaign data at local
scale (a few kilometers) over the Greater G?teborg area along the Swedish west coast during 7–20 May 2001. The focus is on
impact of PBL and LSM parameterizations on simulated meteorological variables important for air quality applications such
as global radiation, diurnal cycle of near-surface air temperature and wind, diurnal cycle intensity, near-surface vertical
temperature gradient, nocturnal temperature inversion, boundary layer height, and low-level jet (LLJ). The model performance
for daytime and nighttime and under different weather conditions is also discussed. The purpose is to examine the performance
of the model using different PBL and LSM parameterizations at local scale in this area for its potential applications in air
quality modeling. The results indicate that the influence of PBL and LSM parameterizations on simulated global radiation,
diurnal cycle of near-surface air temperature and wind speed, diurnal cycle intensity, vertical temperature gradient, nocturnal
temperature inversion and PBL heights, which are critical parameters for air quality applications, is evident. Moreover, the
intensity and location of LLJ are simulated well by all schemes, but there also exist some differences between simulated results
by using different PBL and LSM schemes. Therefore, the choice of PBL and LSM parameterizations is important for MM5 applications
to air quality studies.
Correspondence: Junfeng Miao, Department of Earth Sciences, G?teborg University, P.O. Box 460, 405 30 G?teborg, Sweden 相似文献
2.
Two surface layer parameterization schemes along with five planetary boundary layer (PBL) schemes in the Weather Research and Forecasting model (WRF) are analyzed in order to evaluate the performance of the WRF model in simulating the surface variables and turbulent fluxes over an Indian sub-continent region. These surface layer schemes are based on the fifth-generation Pennsylvania State University—National Center for Atmospheric Research Mesoscale Model (MM5) parameterization; (a) Old MM5 scheme having Businger-Dyer similarity functions and (b) revised MM5 scheme utilizing the functions that are valid for full ranges of atmospheric stabilities. The study suggests that each PBL scheme can reproduce the diurnal variation of 2 m temperature, momentum flux and sensible heat flux irrespective of the surface layer scheme used for the simulations. However, a comparison of model-simulated values of surface variables and turbulent fluxes with observed values suggests that each PBL scheme is found to systematically over-estimate the nocturnal 2 m temperature and 10 m wind speed with both the revised and old schemes during stable conditions. 相似文献
3.
数值预报的误差来源于初始场和模式的误差,集合预报技术是减小这些误差的有效方法。该文以MM5模式作为试验模式框架,模式的积云参数化方案分别取Anthes-Kuo、Grell、Kain-Fritsch和Betts-Miller方案,边界层参数化方案分别取MRF和Eta方案,通过组合4种积云参数化方案和两种边界层参数化方案产生8个集合成员,对1999年华东地区梅雨期间3个降水个例进行48 h集合预报试验。结果显示不同集合成员的预报结果各不相同,积云参数化方案对降水的影响比边界层参数化方案对降水的影响大;不同集合成员预报降水的偏差也各不相同,大多存在湿偏差,量级小的降水的湿偏差程度比量级大的降水的湿偏差程度小;对于不同个例,各成员中预报效果相对较好的成员是不同的,集合平均后可以得到一个比较稳定的预报结果;从集合预报结果中还能得到客观化和定量化的降水概率预报,它能对可能发生的天气现象发出信号。 相似文献
4.
5.
J. Sanjay 《Boundary-Layer Meteorology》2008,129(1):159-177
Data collected during the Land Surface Processes Experiment (LASPEX) in a semi-arid region of the state of Gujarat in north-west
India for a clear sky day (16 May 1997) are used to assess the performance of the atmospheric boundary-layer (ABL) and land-
surface parameterizations in the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR)
Mesoscale Model (MM5). The ABL turbulence parameterizations examined are the Blackadar scheme coupled to a simple soil slab
model (SSM), and the Troen-Mahrt scheme coupled to SSM or to the more sophisticated Noah land-surface model (NSM). The comparison
of several two-way nested high resolution (9-km) MM5 short term 24-h simulations indicate that, although the model is able
to capture the trend in the observed data, the computed results deviate from observations. The NSM with a modest treatment
of vegetation outperforms the SSM in capturing the observed daily variations in surface heat fluxes and aspects of ABL structure
over the tropical land surface at local scales. Detailed analysis showed that, with the incorporation of observed local vegetation
and soil characteristics, the NSM reproduced a realistic surface energy balance and near-surface temperature. It is further
found that the coupling of the NSM with the Troen-Mahrt ABL scheme leads to excessive ABL mixing and a dry bias in the model
simulations. 相似文献
6.
不同边界层参数化方案在暴雨数值模拟中的对比分析 总被引：4，自引：1，他引：3
本文利用非静力平衡的中尺度模式(MM5),通过对一次华南锋前暖区暴雨的数值模拟,比较了3种边界层参数化方案的作用。结果表明：从24小时累积降水的分布来看,MRF方案的预报与实况对比效果最好,其次是Blaekadar高分辨率PBL模式,最差是no PBI,方案。分析MRF方案的输出结果,发现对应每个时刻的累积雨团上空,925hPa都有较强的辐合辐散偶极子与之相配合,而在300hPa则有较强的辐散。不同边界层方案模拟的辐散场有一定的差别,导致了降水的不同预报效果。 相似文献
7.
ENSEMBLE PREDICTION EXPERIMENTS OF TRACKS OF TROPICAL CYCLONES BY USING MULTIPLE CUMULUS PARAMETERIZATION SCHEMES 总被引：1，自引：1，他引：0
Ensemble prediction experiments of the tracks of eight tropical cyclones occurring between 2004 -2006 over the western Pacific have been performed by using MM5 with five cumulus parameterizations chemes. The results show that the predictions of the tracks of the tropical cyclones are sensitive to the selection of cumulus parameterization schemes. Each scheme has its own advantage and disadvantage, and the predications without cumulus parameterization schemes are not the worst, sometimes even better than the others. And all of the three ensemble methods improve the predictions of the tracks significantly, among which the ensemble method without parameterization schemes, the Grell, Betts-Miller and Kain-Fritsch schemes are the best. 相似文献
8.
中尺度气象模式对风场的预报效果与参数化方案的适应性紧密相关.以内蒙古高原丘陵地形、江苏平缓的海陆交界地形2种典型下垫面试验风电场为模拟区域,分别用WRFV3.2 （Weather Research and Forecast Model）模式自带的6种物理过程参数化组合方案预报了2010年1月和7月两个风电场区域的风速和风向,对比分析了参数化组合方案差异对风场预报的影响.结果表明：①内蒙古试验区,边界层MRF方案描述的边界层结构较MYJ方案合理;微物理方案WSM3在夏季的风速预报能力优于WSM6,而冬季相反;复杂地形区域的风场预报需考虑陆面过程参数化方案,尤其是夏季降水发生后,陆面过程对于边界层结构的影响增大,选用Noah优于无陆面过程.②江苏试验区,边界层MRF方案描述的边界层结构较MYJ方案合理;1月陆面过程RUC方案优于陆面热量扩散和Noah;7月陆面热量扩散方案优于RUC和Noah.③风向预报6个方案的预报风向统计与实际记录风向统计有较好的一致性,风向概率分布相似,盛行风向一致且稳定. 相似文献
9.
The Role of Planetary Boundary-Layer Parameterizations in the Air Quality of an Urban Area with Complex Topography 总被引：3，自引：1，他引：2
Elizabeth Bossioli Maria Tombrou Aggeliki Dandou Eleni Athanasopoulou Kostas V. Varotsos 《Boundary-Layer Meteorology》2009,131(1):53-72
The effect of different planetary boundary-layer (PBL) parameterization schemes on the spatial distribution of atmospheric
pollution over the complex topography of the greater Athens area is investigated. Four PBL schemes originally implemented
in a numerical meteorological model and a fifth one simulating the urban effect are examined. Two different atmospheric conditions
are analyzed; a typical summer and a typical winter pollution episode. The relative importance of chemical and physical processes
of the pollution predictions is discussed using process analysis. It is revealed that, for primary pollutants, a local scheme
seems more adequate to represent the maximum observed concentrations while, completely different in structure, a non-local
scheme reproduces the mean observed values in the basin. Concerning secondary pollutants, peak concentration differences,
due to the different PBL schemes, are smoothed out. Nevertheless, the PBL scheme selection shapes the horizontal and the vertical
extension of maximum values. The non-local and semi non-local schemes are superior to the others, favouring strong vertical
mixing and transport towards the surface. The stronger turbulence accommodated effectively by the semi non-local urban scheme
enhances ozone production along the sea-breeze axis and preserves the high ozone concentrations during the nighttime hours
in the urban core. 相似文献
10.
为准确描述我国最大的固定/半固定沙漠-古尔班通古特沙漠区域的大气边界层结构，本文利用该沙漠腹地2017年的梯度铁塔和通量观测数据，基于中尺度气象模式WRF (Weather Research and Forecast v3.7.1)，分析了5种边界层参数化方案在古尔班通古特沙漠的适用性。结果表明：1）采用WRF模拟沙漠腹地近地层内的边界层特征时，2m气温的模拟存在冷偏差，5种边界层参数化方案均能较好地模拟出四个季节2m气温的日变化特征，其中非局地方案ACM2(Asymmetric Convective Model version 2)对2m气温效果最好，局地方案BL方案的模拟偏差最大；2）5种边界层参数化方案均能够模拟出10m风速的日变化特征，其中局地方案BL(Bougeault-Lacarrere)对10m风速效果最佳；3）采用WRF模拟沙漠近地层内的地表通量特征时，感热通量存在高估现象，潜热通量存在低估现象，5种边界层参数化方案均能较好地模拟出四个季节模拟时间段内地表净辐射通量的日变化特征，其中局地方案MYJ(Mellor-Yamada-Janjie)的模拟精度最高。 相似文献
11.
利用WRF-Chem模式,采用3种边界层参数化方案 (YSU, MYJ和ACM2),针对1个晴空、静稳日 (2013年8月26日20:00—27日20:00(北京时)) 进行模拟,着重分析不同边界层参数化方案对夜间残留层形成及日出前后O3浓度垂直分布形式的模拟效果,并与固城站地面及垂直同步观测资料进行对比。结果表明:3种边界层参数化方案均能够模拟出温度及风速的区域分布形式以及风温垂直结构的变化特征;相比之下,MYJ方案模拟的夜间边界层高度较YSU方案和ACM2方案明显偏高,该对比结果可能是导致近地面污染物浓度模拟差异的重要原因;在夜间稳定层结至日出后稳定状态打破的边界层结构演变过程中,采用YSU方案和ACM2方案模拟的温度和风速垂直扩线形式与观测结果更为接近;同样采用非局地闭合的YSU方案和同时考虑局地和非局地闭合的ACM2方案,对于边界层高度内O3浓度垂直分布形式的模拟效果具有明显优势。 相似文献
12.
采用基于集合Kalman滤波数据同化和偏差修正方法的集合预报技术来研究热带气旋的强度预报问题.集合预报系统考虑初值误差和模式误差,利用MM5中尺度模式,采用Anthes-kuo、Grell和Betts-Miller等积云参数化方案和High-res-olution Blaekadar、Burlk-Thompson、MRF等边界层过程的9组不同的组合,分别进行45、60和75 min的短时预报.对9个预报结果采用"镜像法",得到18个集合成员.将蓝金涡旋作为同化的观测场,18个集合成员作为集合Kalman滤波的初始背景集合,采用ENSRF算法和逐点局地分析算法进行同化.同化后的结果作为集合预报的初值,预报过程对模式参数采用前述9种组合,进行72小时预报.通过求取偏差系数对预报结果进行修正,减小模式系统误差.选2003-2004年16个台风过程作为预报个例,讨论偏差修正前后对预报结果的影响.实验结果表明,基于集合Kalman滤波数据同化的热带气旋集合预报相对于非同化的集合预报对路径预报的改进效果优于强度预报.平均而言通过偏差修正,强度集合预报的潜力得到挖掘,绝对误差明显减小,通过偏差修正减小了强度集合预报均值的误差,进而使得预报概率密度函数均值向理论值靠近,从而提高了概率预报的精度和合理性,因此基于集合预报的偏差修正分析方法,是改善热带气旋强度预报水平的有效途径. 相似文献
13.
Intercomparison of Planetary Boundary-Layer Parametrizations in the WRF Model for a Single Day from CASES-99 总被引：11，自引：6，他引：5
This study compares five planetary boundary-layer (PBL) parametrizations in the Weather Research and Forecasting (WRF) numerical
model for a single day from the Cooperative Atmosphere-Surface Exchange Study (CASES-99) field program. The five schemes include
two first-order closure schemes—the Yonsei University (YSU) PBL and Asymmetric Convective Model version 2 (ACM2), and three
turbulent kinetic energy (TKE) closure schemes—the Mellor–Yamada–Janjić (MYJ), quasi-normal scale elimination (QNSE), and
Bougeault–Lacarrére (BouLac) PBL. The comparison results reveal that discrepancies among thermodynamic surface variables from
different schemes are large at daytime, while the variables converge at nighttime with large deviations from those observed.
On the other hand, wind components are more divergent at nighttime with significant biases. Regarding PBL structures, a non-local
scheme with the entrainment flux proportional to the surface flux is favourable in unstable conditions. In stable conditions,
the local TKE closure schemes show better performance. The sensitivity of simulated variables to surface-layer parametrizations
is also investigated to assess relative contributions of the surface-layer parametrizations to typical features of each PBL
scheme. In the surface layer, temperature and moisture are more strongly influenced by surface-layer formulations than by
PBL mixing algorithms in both convective and stable regimes, while wind speed depends on vertical diffusion formulations in
the convective regime. Regarding PBL structures, surface-layer formulations only contribute to near-surface variability and
then PBL mean properties, whereas shapes of the profiles are determined by PBL mixing algorithms. 相似文献
14.
许多研究调查了模式预报对边界层方案的敏感性,但是这些研究基本上针对的是热力驱动的混合边界层。对于动力驱动的边界层,不同边界层方案的不同性能以及所带来的不同边界层气象要素的预报还不清楚。运用WRF3.4.1中三种边界参数化方案（YSU、MYJ、ACM2）对新疆2.28大风过程进行数值模拟分析,结果显示：三种边界参数化方案基本能模拟出发生大风的区域及大风过程中10m风速、2m温度和比湿的变化趋势;三种方案模拟的边界层内大气的温度、湿度出现差异与它们对边界层顶的夹卷过程、边界层内垂直混合的处理有关;YSU方案的模拟结果使得更多的高空动量下传,同时更多的有效位能转化为动能,MYJ方案模拟的20m/s的风场区域更大,受地形影响更明显,边界层内湍流更强。 相似文献
15.
塔克拉玛干沙漠腹地大气边界层参数化方案的模拟评估 总被引：1，自引：0，他引：1
沙尘起沙、沉降、传输均受到沙漠地区大气边界层条件的制约。沙漠地区观测资料匮乏,限制大气边界层模拟效果的检验和评估。利用WRFV3.7.1中尺度数值模式中5种边界层参数化方案(ACM2、BL、MYJ、MYNN2.5、YSU),模拟2014年4月塔克拉玛干沙漠大气边界层特征,并与塔中80 m塔及风廓线雷达晴朗天气下的观测资料对比分析。结果表明:5种方案均能模拟出近地面气温及地表温度,边界层高度,感热、潜热、地表热通量的变化趋势,但未能模拟出边界层风速的日变化趋势,温风湿廓线能较好的反映晴日沙漠地区边界层结构的变化特征,但未模拟出风速随高度变化趋势。沙漠地区下垫面干燥,热容量低,晴天极易形成对流不稳定边界层,非局地湍流参数化方案,ACM2方案是沙漠地区大气边界层模拟较为合理的选择。 相似文献
16.
A. A. M. Holtslag G. J. Steeneveld B. J. H. van de Wiel 《Boundary-Layer Meteorology》2007,125(2):361-376
At present a variety of boundary-layer schemes is in use in numerical models and often a large variation of model results
is found. This is clear from model intercomparisons, such as organized within the GEWEX Atmospheric Boundary Layer Study (GABLS).
In this paper we analyze how the specification of the land-surface temperature affects the results of a boundary-layer scheme,
in particular for stable conditions. As such we use a well established column model of the boundary layer and we vary relevant
parameters in the turbulence scheme for stable conditions. By doing so, we can reproduce the outcome for a variety of boundary-layer
models. This is illustrated with the original set-up of the second GABLS intercomparison study using prescribed geostrophic
winds and land-surface temperatures as inspired by (but not identical to) observations of CASES-99 for a period of more than
two diurnal cycles. The model runs are repeated using a surface temperature that is calculated with a simple land-surface
scheme. In the latter case, it is found that the range of model results in stable conditions is reduced for the sensible heat
fluxes, and the profiles of potential temperature and wind speed. However, in the latter case the modelled surface temperatures
are rather different than with the original set-up, which also impacts on near-surface air temperature and wind speed. As
such it appears that the model results in stable conditions are strongly influenced by non-linear feedbacks in which the magnitude
of the geostrophic wind speed and the related land-surface temperature play an important role. 相似文献
17.
MM5模式中城市冠层参数化方案的设计及其数值试验 总被引：15，自引：5，他引：15
文中在综合国外一些较先进的中尺度模式城市作用参数化方案的基础上 ,从城市下垫面结构对城市边界层大气作用的物理机制及实际应用两方面出发 ,对城市下垫面结构和人为活动等因素对边界层结构的影响及中尺度模式中城市化作用的合理体现等问题进行了较全面的考虑 ,改进和设计出能够较全面、细致地描述城市结构对大气边界层动力、热力结构的影响 ,且适合中尺度模式结构特点的城市冠层参数化方案 (UCP) ,并实现了其与MM5模式的耦合。进行了耦合后的UCP方案及采用原城市作用方案的MM5模式对BECAPEX试验期间北京地区气象条件多重嵌套细尺度进行了模拟试验 ,并与观测结果对比 ,结果表明 :相比于MM 5模式中原有表示城市作用的参数化方案来讲 ,设计的UCP方案在很大程度上提高了MM 5模式对城市边界层热力和动力结构的模拟能力。 相似文献
18.
边界层参数化方案的准确性会影响模式对近地面变量和大气低层热动力结构的模拟,对雷暴等强对流天气的预报非常重要,但边界层方案内在的不确定性使得单一预报具有局限性。为了提高对流尺度数值模式中边界层方案的预报效果,基于WRF（The Weather Research and Forecasting Model）模式,应用随机参数扰动（SPP）方法对Mellor-Yamada-Nakanishi-Niino（MYNN）边界层方案中重要的3个不确定参数进行扰动,探究了该方法对北京地区一次雷暴过程模拟的影响。同时考虑了对流尺度集合预报系统的特点,调整随机参数扰动方法的3个参量（去相关时间尺度、空间尺度和格点标准差）探究了对流尺度中对MYNN方案参数进行扰动的最优设置。结果显示:随机扰动MYNN边界层方案参数（SPPM）方法可以有效提高近地面变量和700 hPa以下低层变量的离散度,同时提高了短时强降水位置和强度的预报技巧。3个参量的试验说明,去相关时间尺度增大到12 h集合离散度有明显提高;格点标准差增大到0.20,预报技巧也略有提高;去相关空间尺度维持在默认值700 km较好,尺度过小（150 km）预报技巧明显降低。上述结果表明,在对流尺度中SPPM方法可以有效表达边界层参数化方案的不确定性,提高集合预报系统的预报技巧。 相似文献
19.
PENN STATE/NCAR MM5 is used to simulate precipitation of the heavy rain process during 12-13 July 1994.The effects of different PBL parameterizations,resolvable scale moisture schemes and cumulus parameterization on the process rainfall simulation are investigated.By comparing the results of hydrostatic and nor.hydrostatic experiments,the nonhydrostatic impact upon precipitation is also examined.It is found in this study thai PENN STATE/NCAR MM5 has advantage not only in theory but also in simulating results with real data.In MM5.however,the selection of physical processes,especially water-cycle process,is very important and crucial to precipitation forecast of the case.It is concluded that the model with Grell (1993) scheme for convection and condensation method for resolvable scale precipitation captured the rainstorm during 12-13 July 1994 in Beijing area more successfully 相似文献
20.
使用WRF中尺度数值模式, 分别选用两种不同的边界层参数化方案 (MYJ, YSU) 和3种陆面参数化方案 (SLAB, Noah, RUC), 对2004年7月1日08:00—7月4日20:00 (北京时) 北京地区夏季边界层结构进行1 km的高分辨模拟。对比分析了近地面层风场、温度场以及边界层的日变化特征, 结果发现:WRF模式基本模拟出了北京夏季边界层的日变化特征; 在边界层方案中, MYJ方案描述的边界层结构较YSU方案合理; Noah陆面模式较好地反映了城市的热岛效应; 无降水时, 风速及边界层高度对于陆面过程不敏感, 而降水发生后, 陆面过程对于边界层结构的影响增大; 各方案模拟的城区风速明显偏大, 这是因为没有充分考虑城市建筑物的阻力作用。 相似文献