空气动力学阻抗算法在半干旱区的应用比较和遥感反演          下载免费PDF全文

张杰  张强  黄建平 《高原气象》2010,29(3):662-670

结合2005年中国西北半干旱区定西试验站的观测资料,使用9种空气动力学方法,估算了阻抗和感热通量,并与涡动相关阻抗结果进行了对比,分析了5～9月涡度相关测得阻抗的平均日变化特征,结果表明:(1)由于西北干旱、半干旱区和黄土高原的稀疏植被地区在植物生长季节内存在温度高、降水少、空气干燥等特点,热量和水汽输送具有特殊性;Choudh-1、Verma-R空气动力学阻抗方法对热量和动量传输的粗糙度长度、热量和动量及水汽输送的修正函数描述得较好,空气动力学阻抗估算精度较好,由此获得的感热效果也较好,较适用于该地区。(2)风速对阻抗起主要作用;植被覆盖度增加和植被密度增大的同时也增加了热量和水汽传输的粗糙度,有助于空气动力学阻抗降低。(3)采用Choudh-1方法和遥感资料反演的阻抗效果较好。  相似文献   

Surface turbulent flux measurements over the Loess Plateau for a semi-arid climate change study   总被引：2，自引：0，他引：2  

左金清  黄建平  王介民  张武  闭建荣  王国印  李维京  付培健 《大气科学进展》2009,26(4):679-691

In order to provide high quality data for climate change studies, the data quality of turbulent flux measurements at the station of SACOL (Semi-Arid Climate & Environment Observatory of Lanzhou University), which is located on a semi-arid grassland over the Loess Plateau in China, has been analyzed in detail. The effects of different procedures of the flux corrections on CO₂, momentum, and latent and sensible heat fluxes were assessed. The result showed that coordinate rotation has a great influence on the momentum flux but little on scalar fluxes. For coordinate rotation using the planar fit method, different regression planes should be determined for different wind direction sectors due to the heterogeneous nature of the ground surface. Sonic temperature correction decreased the sensible heat flux by about 9%, while WPL correction (correction for density fluctuations) increased the latent heat flux by about 10%. WPL correction is also particularly important for CO₂ fluxes. Other procedures of flux corrections, such as the time delay correction and frequency response correction, do not significantly influence the turbulent fluxes. Furthermore, quality tests on stationarity and turbulence development conditions were discussed. Parameterizations of integral turbulent characteristics (ITC) were tested and a specific parameterization scheme was provided for SACOL. The ITC test on turbulence development conditions was suggested to be applied only for the vertical velocity. The combined results of the quality tests showed that about 62%–65% of the total data were of high quality for the latent heat flux and CO₂ flux, and as much as about 76% for the sensible heat flux. For the momentum flux, however, only about 35% of the data were of high quality.  相似文献   

8211台风的结构分析          下载免费PDF全文

肖文俊  杨大升  谢安  黄建平 《海洋学报》1985,7(4):423-432

用与文献[1]完全相同的资料,差分格式和计算方法,对8211台风就高低层环流系统、风速的垂直切变、涡度场、散度场、垂直速度场、辐射特征、温度和稳定度场、质量通量场和纬向垂直环流圈等九个方面进行了结构分析,结果发现,对这次近海台风,700-400hPa的中低层在台风发生发展过程中起的作用很大,各种条件有利于中低层扰动的发展,700hPa以下为对流性稳定,700-400hPa气层为对流性不稳定,这种层结分布,加上积云对流的质量通量的垂直辐散(合)在这一层最强,使700-400hPa的中层成为和周围环境交换属性最集中的一层;也使之成为台风发生发展的主要涡源和动力源,分析200hPa流场发现,台风发展到强盛阶段,这个等压面上在台风外围发展出多通道的辐散流出,这是发生和发展初期所没有的,所以对于8211台风,高层台风外围的辐散流出可能不是最初导致热带气旋发展的原因,而更可能是台风发展过程的结果,根据对南北风分量时间剖面图,中尺度垂直运动和积云对流质量通量随时间的变化以及纬向垂直环流圈随时间的变化等的分析,似乎也支持这种看法。  相似文献   

Inversion of gravity and topography data for the crust thickness of China and its adjacent region   总被引：1，自引：0，他引：1  

黄建平  傅容珊  许萍  黄建华  郑勇 《地震学报(英文版)》2006,19(3):264-272

Introduction Since the middle of the century, gravitational isostasy has been a fundamental hypothesis for inverting the gravity data to find the crust thickness. Geophysicists have done a lot of researches on using gravity data to investigate the depth of Moho discontinuity. Since 1980, the International Lithosphere Program emphasized the importance of investigating the Moho depth variation. Thereafter a lot of results have been published in the world (Braitenberg et al, 2000; Kaban et al,…  相似文献   

Development and application of the monent-ratio imaging algorithm     

黄建平马丽  张晁军 《地震学报(英文版)》2006,19(5):569-580

In the moment-ratio imaging algorithm, which is based on the theory of healing of a wound, the energy of each strong earthquake is distributed around the epicenter according to certain rules, and the features of the Moment-ratio value R are analyzed as the space and time change, so that the relationships between the moment-ration value R and strong earthquakes can be found. In the present paper, regions divided, hypocenter depths and events completed magnitude analyses were carried out in the Chinese catalogue. By applying the moment-ratio imaging algorithm in which the parameters are adjusted, the processes of anomaly evolution which correspond to the epicenter and the surrounding value R before earthquakes of M≥7.0 since 1966 in different areas of China were analyzed. It was found that the range area and imminent time of a coming earthquake could be confirmed quantita- tively by analyzing the abnormal temporal and spatial variation of the value R The results showed that the temporal and spatial variation of the value R could quantitatively reflect the temporal and spatial factors of a coming strong earthquake as well as the rule of medium rupture.  相似文献   

沪宁地区辐射雾的微物理结构及其演变   总被引：12，自引：2，他引：10  

黄建平  梅清银  靳永才  李子华 《气象》1998,24(5):3-8

１９９６年１２月２７￣３１日沪宁地区连续５天出现了浓雾天气。利用三用滴谱仪和ＡＤＡＳ对辐射雾的微物理结构及温、压、湿、风等要素的垂直分布进行了探测。通过对这些观测资料的分析,揭示了该地区辐射雾的微牧师结构特征及其演变过程。结果表明：雾的微物理结构与大气污染程度紧密相关,逆温层的长时间存在可以影响雾的微物理结构。此外,还观测到含水量、谱宽等存在周期为２０￣３０分钟的振荡现象。  相似文献   

辐射雾发展的爆发性特征   总被引：34，自引：0，他引：34  

李子华  黄建平  孙博阳  彭虎 《大气科学》1999,23(5):623-631

根据1996年12月27日沪宁高速公路上雾的观测资料分析，揭示了辐射雾的双层结构和爆发性发展的特征，分析了辐射雾发展的物理过程，讨论了影响辐射雾生消过程的逆温结构和湍流混合问题。  相似文献   

提高测报质量的体会     

黄建平 《气象研究与应用》1991,(4)

气象观测是气象工作的基础。这工作看似简单,实则不易精通,况且有些技术规定仍不断地变更,天气状况的变化更是无常。如果没有一熟练过硬的技术本领,没有良好的职业道德,要想按时、按质、按量地完成这项工作任务是完全不可能的。 怎样才能提高测报质量呢?我通过十多年的不断实践、摸索,反复翻阅了技术汇编、观测规范,以及许多技术资料,虚心求教老师傅,学习先进的工作经验,总结了一套提高测报质量的方法。即“认真——熟练——细致”。遵循这套工作程序,不论什么季节,什么恶劣复杂天气,都能得心应手。我近年在测报工作中取得了一些成绩,连续获得了双二百五十班无错情奖。  相似文献   

500hPa月平均距平场演变的宏观描述   总被引：1，自引：0，他引：1  

黄建平  丑纪范  衣育红 《气象学报》1989,47(4):484-487

近年来,采用数值方法进行长期预报和气候异常的研究有了很大的进展,但是这些研究多是沿用了中短期预报的概念和方法,由于长期天气系统是一个强迫耗散的非线性系统,而“耗散系统最终将趋向维数比原始相空间低的极限集合——吸引子,许多自由度在演变过程中成为‘无关变量’,最终剩下支撑起吸引子的少数自由度”。如果不考虑系统的极其复杂的暂态行为,我们自然可以把这些‘无关变量’去掉,从而把高维动力系统简化成低维动力系统。这个解释H.Haken称做随动原理。本文的目的旨在应用上述原理探讨长期天气异常演变的宏观描述方法。我们希望这里提出的概念和方法将有助于建立有效的长期数值预报模式。  相似文献   

北半球月平均环流异常演变的相拟韵律现象     

黄建平  郜吉东等 《高原气象》1990,9(1):88-92

本文用严格的统计方法和较长时间序列的观测资料对北半球月平均环流相拟性的演变做了比较全面细致的分析。结果表明：两个不同年份的月平均距平场在某个起始月相似后相拟性随之变差，但过了约半年左右变得又相拟。这就是所谓的长期天气异常演变过程中半年左右的想拟韵律现象。  相似文献