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1.
龙先菊  吴晶 《贵州气象》2008,32(2):44-45
总结地区级报表审核工作中应该注意的几点问题及浅析审核中的多种方法,对地级地面报表审核具有一定的指导意义.  相似文献   

2.
本主要是针对本省目前台站在使用和维护UPS电源中出现的诸多问题,提出正确的使用和维护方法,改善台站供电,减少资料丢失具有一定的实际意义。  相似文献   

3.
本对地面气象测报《AHDM4.1》软件在实际工作中存在的一些问题提出了具体解决的方法,对台(站)提高工作时效和测报质量有一定的促进作用。  相似文献   

4.
黄静  张艳武  邱崇践 《高原气象》2008,27(1):128-134
将EOF与SVD方法相结合,利用HIRS/3卫星红外模拟资料和NCEP再分析资料,分析了反演大气温度廓线时的理论误差全球分布特征。结果表明,误差分布与纬度有一定的关系,中、高纬地区的绝对反演误差比低纬地区大,但其相对误差要小于低纬地区。相对误差结果反映出低纬地区的反演能力较差;同时像青藏高原这种大地形的存在对反演结果也有一定的影响。  相似文献   

5.
南昌市降水概率预报方法研究(一)   总被引:1,自引:1,他引:0  
主要介绍了降水概率预报的事件概率回归方法,1997年试用表明这种方法有一定的参考价值。  相似文献   

6.
利用哈拉沁沟流域内各水站点逐日降水量计算出流域的面雨量值。与气象资料进行统计分析,利用逐步回归方法建立了流域内面雨量分级的短期(24小时)预报方法。并对此方法进行了回报检验,证明其预报结果在实际工作中有一定的参考价值。  相似文献   

7.
论近地面层湍流通量观测的一些问题   总被引:5,自引:0,他引:5  
胡陷樵 《高原气象》1990,9(1):74-87
本文回顾并总结了目前在近地面层内观测湍流通量的方法。指出了各种观测方法的适用条件。比较了它们的测量误差和它们的优缺点,并讨论了各种测量方法存在的问题。该文的讨论对于选择近地面层湍流通量观测方案、提高观测精度、评价观测结果并对结果进行修正都有一定参考价值。  相似文献   

8.
涡度相关仪倾斜订正方法的比较及应用   总被引:5,自引:2,他引:3  
利用973暴雨项目2002年在安徽肥西观测的涡度相关资料,针对目前涡度相关法中存在的仪器倾斜误差问题,采用两种倾斜订正方法计算湍流参数并进行对比分析.结果表明,三次坐标轴旋转倾斜订正方法和平面拟合方法均可以对仪器倾斜引起的误差进行坐标旋转订正,有效剔除仪器倾斜引起的侧向应力的影响,以及仪彝倾斜时水平方向风速引起的虚假湍流通量,提高了湍流通量的计算精度.两种倾斜订正方法各有一定适用条倬,平面拟合方法优于三次坐标轴旋转倾斜订正方法.  相似文献   

9.
介绍了最优气候值方法,并利用该方法对3站(科尔沁区、开鲁、鲁北)1996-2006年夏季平均降水量和科区5—9月降水量进行了预测。上述结果表明,这种预测方法具有一定的预测能力,可以在实际业务中参考使用。  相似文献   

10.
我国现有短期气候业务预测方法综述   总被引:6,自引:0,他引:6       下载免费PDF全文
对我国短期气候业务预测方法的综合分析表明 :我国现有的短期气候业务预测经验和统计方法仍是主要的 ;物理因子和前兆强信号结合天气气候学分析的概念预测模型方法在业务预测中发挥重要作用 ;动力模式预测方法在业务预测中取得一定效果 .随着动力模式的进一步发展 ,短期气候业务预测将逐步走向以动力模式客观预报为指导预报的新阶段  相似文献   

11.
Summary During an expedition to the high Andes of Southern Peru in June–July 1977, measurements of direct solar radiation in four spectral bands (0.270–0.530–0.630–0.695–2.900 ) were conducted at six sites in elevations ranging from sea level to 5645 m. These measurements were evaluated in Langley plots to determine total optical depths () and irradiances at the top of the atmosphere. In addition, water vapor optical depths (wv) were calculated from the mean radiosounding over Lima during the expedition, and Rayleigh (ray) and ozone (oz) optical depths were obtained from published tabulations. Subtracting ray, oz, and wv from yielded estimates of aerosol optical depth aer. The components ray and oz decrease from the shorter towards the longer wavelength bands and from the lower towards the higher elevation sites; aer also decreases towards the higher elevations. Particularly pronounced is the decrease of aer and from the lowlands of the Pacific coast to the highlands of the interior, reflecting the effect of a persistent lower-tropospheric inversion and the contrast from the marine boundary layer to the clear atmosphere of the high Andes.With 4 Figures  相似文献   

12.
This article presents nine statements which are generally accepted as true. However, when they are applied to a particular situation, in this case the recent prolonged drought in the Sahelian zone in West Africa, they are as often untrue as they are true. For example, such generalizations as people learn from their mistakes or when the rains come, everything will return to normal or technology is the answer, when applied uncritically to a specific situation often prove to become part of the problem as well as a hindrance to the attainment of a solution to that problem.It is strongly suggested that these nine generalizations, here called fallacies, be carefully assessed when applied, thereby removing one more obstacle in dealing with environmental problems in general and natural hazards in particular.Published in Michael H. Glantz (ed.), The Politics of Natural Disasters: The Case of the Sahel Drought (NY: Praeger Publ., 1976) reprinted by permission.Michael H. Glantz is a scientist in the Advanced Study Program at the National Center for Atmospheric Research which is sponsored by the National Science Foundation.  相似文献   

13.
利用林芝国家基准气侯站冬季(2018年12月-2019年2月),CHP1型太阳直接辐射传感器、DFC2型光电式数字日照计、暗筒式日照计在不同天气模式下的测量值分类进行对比分析。结果表明:三种仪器两两测量值对比绝对偏差和相对偏差,直接辐射传感器测量值在“阴云”、“多云”、“云晴”比暗筒式日照计低,从大到小的顺序为“晴天”>“阴云”>“多云”。DFC2型光电式数字日照计仅“晴天”测量值比暗筒式日照计高,其余则低。从大到小顺序为“晴天”>“多云”>“阴云”;三种设备测量值可以相互替代,取消人工观测设备后,日照资料可以合并使用。  相似文献   

14.
Periodicity of annual precipitation in different climate regions of Croatia   总被引:1,自引:1,他引:0  
Summary The periodicity of a 100-year series of annual precipitation over Croatia has been studied by means of power spectrum analysis at 3 stations representing the different climatic regions of Croatia. The annual precipitation variance spectra in the continental lowland (Osijek) and at the north East Adriatic coast (Crikvenica) can be fitted by Markov white noise continuum, but in the transitional region between the Dinaric Alps and the Pannonian lowland (Zagreb-Gri) a non-white noise continuum is necessary. Quasi-periodic oscillations appear in two spectra ranges: short (2.2 and 4.7 years) and medium (25.0 and 33.3 years). These results are compared with those of other authors for other parts of the Europe.With 2 Figures  相似文献   

15.
Six locations across mainland Portugal were selected for exposing Parmelia sulcata, for a one-year period (8 months for one site), with simultaneous measurement of total (dry + wet) deposition (one-month periods). The exposed lichens and the total (dry + wet) deposition were analysed for cobalt contents by INAA (instrumental neutron activation analysis) and ICP-MS (inductively coupled plasma mass spectroscopy), respectively. The designated wet deposition was evaluated through the collected water volume; the designated dry deposition was assessed after the (dried) residual mass of the wet deposition. An excellent agreement between Co contents in exposed lichens and the cumulative (1) Co contents in the dry deposition, (2) dry deposition, and (3) wet deposition has been found for the locations with alternate drought and precipitation months, high dry deposition, and high Co contents in the latter. Continuous rainfall was found to hinder the Co accumulation in the lichen due to its release from the lichen and/or lower Co contents in the dry deposition. At three locations, P. sulcata Co contents, after subtraction of the background (before exposure), equalled or exceeded the Co contents in the cumulative dry deposition at the end of the exposure time. The optimal exposure period for this species likely depends on the exposure conditions.  相似文献   

16.
短期集合降水概率预报试验   总被引:11,自引:2,他引:11       下载免费PDF全文
以MM5模式作为试验模式, 通过选取不同的物理过程参数化方案产生8个集合成员, 分别用平均法、相关法和Rank法对2001年11月至2002年5月期间的22个降水个例进行短期集合降水概率预报试验。试验结果显示对小雨—大暴雨6类降水的概率预报, Rank法的综合预报效果明显好于相关法和平均法, 相关法的综合预报效果与平均法基本相同; 无论从均方误差角度还是从命中率和假警报率的相对大小角度, 对小雨、中雨、大雨和暴雨各量级以上降水的概率预报, Rank法的平均预报效果是三种方法中最好的, 相关法的平均预报效果与平均法相同; Rank法好于平均法的平均幅度从均方误差角度较大, 从命中率和假警报率的相对大小角度则较小。平均而言, 三种方法对各量级以上降水的概率预报都是有技巧预报, 对量级小的降水的概率预报技巧高于对量级大的降水的概率预报技巧。  相似文献   

17.
In the summer of 1988/89 flights were carried out in the Coorong coastal area of South Australia to investigate sea-breeze fronts. The flights yielded data sets of the structure of the fronts in the cross-frontal direction with a spatial resolution of approximately 3 m. The study is focused on the budgets of sensible and latent heat in the vicinity of the front and on frontogenesis/frontolysis processes which are closely related to budget considerations.The frontogenesis relationships and the budgets were established on a 2 km length scale by low-pass filtering of the space series. As the wind components were measured with high accuracy, all processes which determine frontogenesis could be evaluated and are displayed in x,z-cross-sections: these are the confluence, shear and diabatic effects, all of which play a role in q/x-, q/z-, /x- as well as /z-frontogenesis. A detailed analysis is given for two different states of frontal development. The presented results shed much light on the governing physical processes in the frontal region with strong emphasis on the effects of confluence-generated updrafts, on shear instabilities causing bulges and clefts in the frontal surface as well as producing the elevated frontal head, and on processes related to differential heating and moistening.  相似文献   

18.
Summary An analysis of the report of the (U.S.) National Academy of Sciences (NAS) on atmospheric effects of a nuclear exchange leads to conclusions that differ from those of the NAS and of the earlier TTAPS and AMBIO studies. Any cooling of the earth's surface is likely to beshort-lived because of rapid removal of the smoke clouds originating from nuclear burst-initiated fires, andminor because of appreciable green-house effects due to several distinct physical causes. (One of these, neglected in prior analyses, is the infrared absorption from cirrus clouds produced directly by the nuclear bursts.) Taken together, these effects may even induce slight surface warming (nuclear summer) instead of cooling (nuclear winter). The consequences to atmospheric ozone are similarly ambiguous; depending on the detailed nuclear scenario, the net ozone content may increase-rather than decrease as argued by TTAPS. Experiments could settle some uncertainties.With 2 Figures  相似文献   

19.
北京“7.21”特大暴雨环流形势极端性客观分析   总被引:14,自引:3,他引:11  
2012年7月21日(简称“7.21”),北京发生了自1951年以来最强的暴雨事件。利用倾斜旋转T模态主成分分析法和美国国家环境预报中心/美国国家大气研究中心再分析资料,探讨了北京“7.21”特大暴雨的大尺度环流形势的极端性。结果表明,北京“7.21”暴雨日所属的大尺度环流型在1951—2012年夏季出现的频率为10.9%,而在“7.21”同类环流型中暴雨出现的概率为4.51%。和同类暴雨日平均场相比,“7.21”暴雨日当天西太平洋副热带高压西伸更强,北京地区对流层低空急流更强,并伴随环境大气中极端充沛的可降水量和较大的风垂直切变。在“7.21”同类环流型下的621 d中,“7.21”暴雨日北京南侧的低空急流排在第54位,北京局地风垂直切变排在第209位,可降水量排在第8位,显示出其在低空急流和可降水量上的极端性。1951—2012年夏季,具有“7.21”暴雨日同类环流形势、且925 hPa低空急流和可降水量均达到或超过“7.21”暴雨日值的个例有3次,相当于每21年发生一次。  相似文献   

20.
The reactions of alkoxy radicals determine to a large extent the products formed during the atmospheric degradations of emitted organic compounds. Experimental data concerning the decompositions, 1,5-H shift isomerizations and reactions with O2 of several classes of alkoxy radicals are inconsistent with literature estimations of their absolute or relative rate constants. An alternative, although empirical, method for assessing the relative importance under atmospheric conditions of the reactions of alkoxy radicals with O2 versus decomposition was derived. This estimation method utilizes the differences in the heats of reaction, (H)=(Hdecomposition–HO 2 reaction), between these two reactions pathways. For (H)[22–0.5(HO 2 reaction)], alkoxy radical decomposition dominates over the reaction with O2 at room temperature and atmospheric pressure of air, while for (H)[25-0.5(HO 2 reaction)], the O2 reaction dominates over decomposition (where the units of H are in kcal mol–1). The utility and shortcomings of this approach are discussed. It is concluded that further studies concerning the reactions of alkoxy radicals are needed.  相似文献   

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