一种用于气候相关资料管理和研究的新手段          下载免费PDF全文

L. V. Novak  李丽 《气象科技》1985,(4):36-41

1.前言美国国家航空和宇宙航行管理局(NASA)的试验性气候资料库管理系统(Pilot Climate Data Base Management System,缩写为PCDBMS)为研究人员利用气候相关资料提供了一种新的手段。PCDBMS的建立是为了对收集到的大量有价值的气候资料进行集中管理。这一系统可提供某些选定的NASA和非NASA资料集  相似文献   

从短期风记录进行风能的估算          下载免费PDF全文

V. R. Barros  E. A. Estevan  温明  李力 《气象科技》1985,(4):52-59

1.引言为便于判断是否适合安装风能转换系统(WECS)和对候选地点作出选择,需要定点的长期平均风能资料。由于常常不可能在每个地点上都有长期可用的平均资料,所以切合实际的办法是依靠短期的测量(但足以作出适当的估算)或者是依靠别的可替换的估算方法。 Corotis等人(1977)发现,由一年的数据  相似文献   

灌溉地土壤湿度快速测定法          下载免费PDF全文

Р.Н.Олейник  Н.Г.Шелудко  鹿洁忠 《气象科技》1985,(4):87-88

用土钻法测定土壤湿度的工作相当繁重,所以要找出一种简便的测定土壤湿度的新方法。(1970)等为了减轻测定土壤湿度的繁重工作曾作过一些研究,其中包括灌溉地土壤湿度的测定问题。(1970)等曾提出,根据暗栗钙土30cm和40cm深度的平均湿度来计算0—70cm和0—100cm土层的湿度,并认为在这些土层的湿度间存在着线性关系。  相似文献   

固态正交风速表          下载免费PDF全文

F.W.Hagen  R.V.Deleo  许继武 《气象科技》1985,(5):91-95

一、引言美国Rosemount公司研制了一种正交即全方位风速表,利用气动信号测量风速和风向。传感器是一种结实的固态装置,无运动部件,经得起野外粗放式应用,并能在世界范围内各种恶劣气候环境下提供精确可靠的风资料。传感器有电气除冰装置,适合全天候工作。传感器产生经放大的压差,它与正交方向的风速成正比。内部的固体压力变换器  相似文献   

全球增暖对甲烷生物圈源的影响及其气候后果          下载免费PDF全文

S.Hamee  R.D.Cess  周国华 《气象科技》1985,(6):56-60

1.引言人们认为工业活动对全球气候的影响主要是二氧化碳的温室效应。近来,已经提出在北半球观测到的可能是由于人类活动产生的较高的臭氧浓度会造成气候增温0.2 K(Fishman等,1979)。而且,在气候-化学耦合  相似文献   

Temperature changes over Eurasia during the late summer of 1979     

Ding Yihui  T. Iwashim  T. Murakami 《大气科学进展》1985,2(2):200-214

During the late summer of 1979, massive changes occurred in the distribution of temperature over Eur asia north of 15oN. At 300 hPa, zonal mean temperature averaged over Eurasia along 20o－25oN de-creased sharply around 23 August. An abrupt decrease in 300 hPa zonal mean temperature also occurred over extensive mid-latitude zones (40o－55oN) around 18 August, i. e., about 5 days prior to the monsoon withdrawal over South Asia.The intensity and location of N－S oriented, vertical overturning underwent significant changes over Eurasia during the transition from summer to fall. Near 20o－25oN, zonal mean updrafts weakened con-siderably during the transition period (18－27 August). Around 45oN, zonal mean downdrafts and the asso-ciated cooling (radiative) rate increased considerably during the transition period.Near 15oN, 300 hPa zonal mean temperature fluctuated nearly periodically with an approximate 40-day period. These fluctuations appear to be associated with a small imbalance between 40-day filtered adiabatic cooling (heating) and diabatic heating (cooling).  相似文献   

A NUMERICAL EXPERIMENTAL STUDY OF SOME DYNAMICAL EFFECTS ON SOUTHERN ASIATIC HIGH     

斯公望  Donald R.Johnson 《大气科学进展》1985,(2)

Using a barotropic, steady and linearised vorticity equation and using 250 hPa observed basic flow and global divergence fifeld ffrom the active summer monsoon phase (00 GMT 26 June-12 GMT 29 June) 1979, the dynamical effects of linear absolute vorticity advection, vorticity generation due to divergence and vorticity dissipation due to frictional damping have been tested to understand their influence on Southern Asiatic High (SAH). The key experimental results art: (1) The SAH, one of the maior planetary-scale disturbances, is generated from the upper basic flow by the forcing of the upper tropospheric divergence over southeast Asia during the active summer monsoon phase, (2) Linear absolute vorticity advection and frictional damping of vorticity play an important role in the determination of the location of the SAH. (3) The destruction and recovery of planetary-scale geostrophic balance is an important mechanism for the west-east oscillation of the SAH.  相似文献   

The atmospheric heat budget over the western part of the Tibetan plateau during Monex, 1979   总被引：1，自引：0，他引：1  

Feng Zhiqiang  Elmar R.Reiter  Chen Longxun 《大气科学进展》1985,2(4):455-468

The atmospheric heat source strength over western Tibet has been computed for the period beginning with the last ten days in May, 1979 and extending through August, 1979. Our results show a significantly smaller heat source than that obtained by other authors. The discrepancy is mainly due to adjustments in the dray, coefficient suggested by observations and numerical modeling experiments. We subdivided western Tibet into northern and southern parts. In the north sensible heating, SH, provides the dominant input into the atmospheric heat source, whereas in the southern part latent heat, LP, offers a significant contribution after the start of the rainy season.Detailed heat budget calculations were also carried out over limited regions of southwestern Tibet which hau good station coverage. During periods with area-averaged rainfall ≤1 mm/day an atmospheric heat source maximum was located over southwestern Tibet near the 500 hPa level, while a heat sink dominated the upper troposphere in a layer of subsidence. When rainfall exceeded 4 mm/day, ascending motions and heal sources prevailed throughout the troposphere with maxima near 400 hPa. Time series analyses of the heat sourcs components show that the total atmospheric heat source is strongly modulated by the release of latent heat. Atmospheric radiational cooling reveals a phase shift in its relation with precipitation. During the first part of the observation period a correlation of that cooling exists mainly with the net radiation at the top of the atmosphere, during the last part with the net radiation at the ground.  相似文献   

测定断层面解的地震波形反演方法   总被引：3，自引：0，他引：3  

姚振兴  D. V. Helmberger 《地震》1985,(3)

测定地震的断层面解,是地震学研究的重要任务。近年来的研究结果表明,用综合地震图模拟远场体波波形是测定地震断层面解的有效方法。远场体波地球介质响应近似地为一单位函数,因此远场体波综合地震图计算十分方便。该方法的缺点是只适用于大地震(震级M>6.5)。由于地震震源机制的影响,走滑断层的地震在远场(震中距离  相似文献   

有限单元分析中的移动边界方法          下载免费PDF全文

冯锐  E.R.Kanasewich 《地球物理学报》1985,28(1):53-63

本文就波动问题提出一种移动边界的有限单元解法。此时模型边界的位置不是固定的,它将随着波前向前推进和退回,以保证在计算时间长度内边界反射波不到达观测点。文中给出了计算边界有效载荷的递推公式,可以简便有效地避免虚假反射波的干扰。为降低运算量和虚模型中的存贮,应适当选取移动间隔,截断误差和移动起点。对于层状模型,若采用直接积分的中心差分方法,计算过程十分简单,也可用于有限差分等方法的计算中。该方法在应用上的限制是对计算机内存量的要求较通常方法为大。  相似文献