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The analysis of summer rainfall intensity in China is carried on for the purpose of practical application of climatic data to the natural resources development. It contains three main parts: 1) a brief survey of the distribution of mean intensity of rain in summer months; 2) an investigation of the record maxima of rainfall intensity at different stations in respective geographical regions; 3) a statistical analysis of the time variations of yearly maximum intensities at 12 representative stations and a calculation... The analysis of summer rainfall intensity in China is carried on for the purpose of practical application of climatic data to the natural resources development. It contains three main parts: 1) a brief survey of the distribution of mean intensity of rain in summer months; 2) an investigation of the record maxima of rainfall intensity at different stations in respective geographical regions; 3) a statistical analysis of the time variations of yearly maximum intensities at 12 representative stations and a calculation of expected values of daily rainfall intensity for different ranges of time period. 本文關於中國夏季日降水强度的分析,是以对國民經济服务为目的的。全文分三部分:第一部分,讨论了夏季日降水强度的平均分佈,指出初夏的强度,南方大於北方,七月裹就北方大於南方。最大強度成面出現,反映着降水强度和气旋路徑,地理环境的相互联系。第二部分,以自然地理區域为單位,討論各級絕对最大强度的出現频率,众數和平均数等。还指出了各大區域發生絕对最大强度降水的地面天气形势。第三部分,分析了十二个代表性测站最大降水强度的時間变化,应用統計方法,計算出各地點在某一年代之內可能出現的絕对最大日降水强度。 Since the beginning of the last half century, the science of hydrology through successive steps of development has advanced to the realm of quantitative analysis. Engineers employed empirical methods to compute river discharges from precipitation data in answer to the ever-increasing demands made upon hydrologic analyses for engineering works. Yet for the phenomena of conflux of flows from precipitations, there exist only meager and fragmental quantitative analyses, without, so far, a systematic study of their... Since the beginning of the last half century, the science of hydrology through successive steps of development has advanced to the realm of quantitative analysis. Engineers employed empirical methods to compute river discharges from precipitation data in answer to the ever-increasing demands made upon hydrologic analyses for engineering works. Yet for the phenomena of conflux of flows from precipitations, there exist only meager and fragmental quantitative analyses, without, so far, a systematic study of their underlying theories recorded in literature. On account of this, the progress of hydrology in respect to theory as well as to prac- tice has been retarded. By means of hydrodynamic analysis, the author has tentatively made an approach to the establishment of such a scheme of theories, in which he divided the rainfall-runoff phenomena into three parts for separate analyses, i. e., the occurrence of runoff due to rainfall at a surface point, the surface flow, and. the conflux of channel flows. This paper is devoted to the first part, which is, in essence, an analysis of the basic hydrologic phenomena. The theories thus established may be used as a guide for various hydrologic analyses in practice, may be based upon to examine the validity of various methods of hydrologic calculations, and may be further used to develop an approximate yet rational method for computing discharges from precipitation data. In this paper, the author proposes a scheme of underlying theories for analyzing the hydrograph of surface flow due to rainfall at a point, in which the essence of basic hydrologic phenomena is revealed, and this is accompanied with calculations of an example. In the earlier years, R. E. Horton established a theory of correlations of rainfall and runoff from small drainage basins by analyzing the data of Homer's sprinkler experiments. Thereafter, researchers basing upon his theories and methods analyzed the relations between rainfall and runoff by sprinkler experiments or data from natural areas. On account of the fact that Horton's analysis does not begin with an accurate hydrodynamical viewpoint, problems are bound to arise in practice due to defects in the underlying theories. Shortcomings of Homer's analysis on the basis of the author's theories are pointed out and the practical value of sprinkler experiments estimated. A method proposed by E. V. Bodakoff for computing discharges due to storms on small basins has raised wide discussions among the Soviet scholars, many of whom hold different views. The author hereby points out the main shortcomings of Bodakoff's method, and gives a numerical example with results compared with those computed by the author's method, thus showing the limitations of Bodakoff's method in practical applications. 半世紀來,水文学在發展的过程中已進入了定量分析的途徑;工程師們曾用各种經驗性的方法依據降水的资料推演河槽裹水流的現象,以应各种工程建設对於水文分析的要求。但是对於降水集流的过程始終祇有一些零星、片面的数值分析,没有一套完整的理論系統,因此阻碍着水文学在理論与应用方面的發展。作者曾用流体力学的分析法初步建立了降水集流的理論系統,把降水集流的过程分為三個階段:雨降地面逕流的產生、地面流、槽流之滙集,分别予以分析。本文便是其中第一階段,亦即最基本水文現象的分析。这些建立了的理論可以用為指導各种水文分析的南針,用為評論各种水文計算法的依據,並可用以創造一种近似而合理的方法,从降水資料推算逕流資料。本文中作者貢献一套理論,以分析地面點上降雨產生逕流的过程,揭發了基本水文現象的本質,最後並列舉实例的計算。早年郝登(R.E.Horton)曾依據郝納(W.W.Homer)的地面流实驗資料建立了一套在小地域內降水和逕流關係之理論,其後学者們根據他的理論和方法,用人工降雨法或流域資料实測法來確定降水和逕流間的關係。郝登的分析並没有从準確的動力学观... 半世紀來,水文学在發展的过程中已進入了定量分析的途徑;工程師們曾用各种經驗性的方法依據降水的资料推演河槽裹水流的現象,以应各种工程建設对於水文分析的要求。但是对於降水集流的过程始終祇有一些零星、片面的数值分析,没有一套完整的理論系統,因此阻碍着水文学在理論与应用方面的發展。作者曾用流体力学的分析法初步建立了降水集流的理論系統,把降水集流的过程分為三個階段:雨降地面逕流的產生、地面流、槽流之滙集,分别予以分析。本文便是其中第一階段,亦即最基本水文現象的分析。这些建立了的理論可以用為指導各种水文分析的南針,用為評論各种水文計算法的依據,並可用以創造一种近似而合理的方法,从降水資料推算逕流資料。本文中作者貢献一套理論,以分析地面點上降雨產生逕流的过程,揭發了基本水文現象的本質,最後並列舉实例的計算。早年郝登(R.E.Horton)曾依據郝納(W.W.Homer)的地面流实驗資料建立了一套在小地域內降水和逕流關係之理論,其後学者們根據他的理論和方法,用人工降雨法或流域資料实測法來確定降水和逕流間的關係。郝登的分析並没有从準確的動力学观點出發。在实際分析中發生了欠缺理論基礎的根本問題。这方面作者持着不同的意見。本文中根據作者的理論指出了郝登分析法的癥結所在,並估計了人工降雨实驗法的实用價值之限度。波達闊夫曾建議暴雨逕流之一种計算法,引起了苏联学者的廣泛討論,很多人持有不同的意見。作者於文中指出了波氏等方法發生問題的症結所在;並用实例計算和作者的方法比較,說明了波氏法在实用中的準確限度。 This is a brief report of a preliminary survey of certain rain-bearing systems over China in later spring and summer. In the first part, a general description of the methods of analysis used in this survey is given. As the temperature and wind fields are weak, and the precipitation is heavy, smaller intervals for the isotherms and contours in the constant pressure surface and pseudo-equivalent potential instead of potential temperature in the cross section analysis are used.In the second part, there are descriptions... This is a brief report of a preliminary survey of certain rain-bearing systems over China in later spring and summer. In the first part, a general description of the methods of analysis used in this survey is given. As the temperature and wind fields are weak, and the precipitation is heavy, smaller intervals for the isotherms and contours in the constant pressure surface and pseudo-equivalent potential instead of potential temperature in the cross section analysis are used.In the second part, there are descriptions of the structure and development of five frequently observed rain-bearing systems i.e. cold front, blocking high and cold vortex, monsoon heat low, warm front and typhoon.The last part consists of discussions of some points of view in synoptic meteorology in China. It is stated that the monsoon precipitation is various in intensity and duration according the large-scale flow patterns. The difference of moisture content in the middle troposphere as a criterion for the identification of equatorial or tropical maritime air mass is proved to be missleading. It is shown that the upper air moist content is high only within the raining region near the polar or equatorial front. To the south of the equatorial front within the so-called equatorial air mass, the moist content in the middle troposphere is as low as within the tropical maritime air mass. It is the convergence and lifting of the tropical air mass which releases the convective instability and induces the surface moist air rising to the middle troposphere. The phenomenon of the forward-inclination of the so-called North-West Trough based on the time cross-section of wind is proved to be a mistake by combining two systems into one trough. The terminology of shear line, and the correct application of synoptic models in weather analysis and forecas-ting are also discussed. 本文是一年来从事夏季降水天气初步普查的简单报告。第一节首先指出所用分析方法与一般国内所通用者,稍有不同。高空等压面分析,取20米作为等高缐间隔,2℃作为等温缐间隔。代替40米及5℃的间隔,以适应夏半年较弱的温度场与气压形势场,在剖面分析中以等假相当位温缐代替位温缐,与等温缐配合以适应降水天气的凝结降水过程。 第二节讨论了五种夏半年基本降水天气系统,即冷锋、阻塞高压与冷涡、季风热低压、 暖锋及有风的结构,并简单地叙述了演变过程。 第三节对某些天气概念提供一些批判性的讨论。根据现已增加的观测材料,论证季风与梅雨是多样性的,决定于大规模的温度场与流场特性,以高空湿度大小区分赤道气团与热带海洋气团,证明是不适当的,因为中国赤道锋降水区域以南,即在所谓南南季风的赤道气团中,中层大气仍是干燥的。降水区域内,中层对流层的大量水份,是由于辐合或抬升的作用,使潜势的对流不稳定性成为现实的不稳定性,而由下层空气上升带上去的。文中还论证了所谓西北槽槽缐前倾是将两个系统混作—个系统的不正确桔果。最后还讨论了切交缐及一般模型在天气分析预报中的应用与限制。
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