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1.
Popov’s infiltration-capacitive model of the spring runoff, including the computation of the runoff losses due to evaporation in the period of snow melting and losses due to evaporation and absorption in the period of exhaustion of the sheet inflow into the channel net, is used. Equations to forecast the spring snowmelt flood runoff, taking account of the frozen soil melting, are derived. The method of estimation of their parameters on the base of the joint use of linear regression and optimization methods is realized. It is demonstrated that factors of the autumn moistening and freezing of soils of basins in the beginning of winter influence the spring runoff losses. The integrated index of the initial state of the basin, taking account of mentioned factors, is proposed.  相似文献   

2.
A method of diagnostic calculation of the maximal wind speed in the tropical cyclone, its radius, and central pressure is proposed taking into account large-scale air motions in a low-gradient baric field between subtropical anticyclones. The results of such calculations are considered. A conclusion is made about sufficient accuracy of calculations of the parameters within the tropical zone using only dynamic factors.  相似文献   

3.
A new method for computing the surface transfer coefficients is proposed, based on state-of-the-art empirical flux-profile relationships. The influence of the roughness length ratio is first demonstrated with the classical iterative calculation method. Then a non-iterative algorithm is developed, taking into account the difference between momentum and heat roughness lengths.The new method is validated by comparison with the reference iterative computation. The large gain-in computer processing time (CPU) time gain for the calculation of surface fluxes in Eulerian grid models is finally assessed.  相似文献   

4.
Estimated are additional errors in taking account of the river runoff during different phases of high water and snowmelt floods using the observational data from gaging stations at the absence of increased-frequency measurements of the water level (due to the lack or downtime of recorders). Described is a method for determination of these errors. Using the data collected on 118 gaging stations on 58 rivers in different regions of Russia and the former USSR for seven years of observations, determined are the possible additional errors of average daily, monthly and annual water flows of the rivers of different sizes as well as the total errors that take account of the additional errors.  相似文献   

5.
Developing appropriate climate change adaptations to protect biodiversity requires taking into account the dynamics of agro-ecological and socio-economic change. A framework for approaching this problem was proposed, but not applied in detail, as part of a major biodiversity and climate change report prepared in Australia. This paper describes the first trial application of the method. It was applied across Vietnam as the Government is interested in identifying adaptation options and detailed data are readily available for its 65 provinces. The process involves identifying ecoregions and collating information for each region based on the current conditions and trends in biodiversity, population, income and agricultural production. Climate change scenarios are identified for each region, together with governance options. Educational needs and key adaptation actions are then identified for each region taking into account the agro-ecological and socio-economic input data. It is concluded that the framework could easily be applied in other countries and should assist the development of strategic adaptation options.  相似文献   

6.
Results are considered of study of climate global warming effects on hail climatology and on technique of estimation of physical efficiency of hail protection taking account of the region hail danger trend. It is found that during last 30 years, occurrence frequency of hail and the number of heavy hailstorms in the mountainous areas of the Northern Caucasus decreased, on average, by a factor of 1.5–2, and in the foothill areas increased by 15–20%. It is shown that efficiency of hail protection works should be estimated taking into account the hail danger trend for each region.  相似文献   

7.
Summary  A major problem of climatology are the relationships among climate variables and between climate variables and climate factors on a climatological time scale. By averaging an equation system for heat fluxes on the earth surface and taking into consideration the water balance equation, an equation system is derived, by means of which the annual means of the turbulent heat fluxes can be calculated. The input variables used are the annual means of the climate variables and the parameters of climate factors taking into account the surface properties. The results obtained for the annual means of the heat fluxes are compared with the measurements using the REKLIP network. Finally, the method for determining the whole-area distribution of turbulent heat fluxes is applied to the REKLIP area. Received August 13, 1999 Revised February 15, 2000  相似文献   

8.
Considered is the operational method of the automatic forecasting of severe squalls (in the gradations of 20–24 m/s and ≥25 m/s) implemented in the Hydrometcenter of Russia as well as the ways to improve it in order to reduce “false alarms.” The problem is solved by means of increasing the accuracy of forecasting surface humidity and taking additional account of the predictor of numerical identification of synoptic conditions favoring the formation of severe squalls. Presented are the examples of forecasts.  相似文献   

9.
介绍一种长期趋势预报方法,该法结合预报经验,按照形势变化特征对500和100hPa高度,太平洋海面温度等多层次月平均格点资料进行分区统计,然后用相似离度理论做计算。其中,既同时考虑空间多层次的气象信息,又从连续几个月的信息变化去进行动态的相似综合,力图使相似比较中的片面性得到改善。  相似文献   

10.
大气混合层高度的模式计算和分析   总被引:3,自引:1,他引:2  
曾智华 《高原气象》2004,23(3):368-373
设计了一套描述混合对流层平均状况的平板模式.模拟了混合层平均要素随时间的演变过程。采用能量学方法,通过考虑影响混合层演变的浮力、风切变及下沉等因子,对混合层高度随时间变化的过程进行数值模拟计算,并与实际观测资料比较。结果表明.模式可以较好地应用于实际业务预报中,同时改进了模式的计算方法.分析了各种物理参数对混合层高度变化的不同影响和物理成因。  相似文献   

11.
基于30省区CGE模型,模拟分析了碳排放许可的强度分配标准对我国区域协调发展的影响。结果表明:按行业属性设定强度分配标准会加剧区域经济发展不平衡状况;按区域经济发展水平设定强度分配标准,对区域协调发展的影响较小,但会对高排放行业造成较大的冲击。中央政府基于强度分配标准,参考区域经济发展水平,将碳排放许可分配到各个省份,然后各个省份再参考行业特点将碳排放许可分配给机制覆盖行业的实体或排放源,这样的两阶段分配结构是较为现实的、具有可操作性的政策选择。  相似文献   

12.
A one-dimensional model of fast ice wind-induced break-up developed before was adapted for two-dimensional case that enabled to explain many regularities of this phenomenon. A numerical scheme is proposed of the integration of the acting stresses and potential resistivity by the fast ice area as well as the method for taking into account the correlation between the wind direction and prevailing coastline orientation that enables to simulate practically any combination of tensile and shearing stresses in the basins of arbitrary shape. The seasonal variability of strengthening ice properties is taken into account. All numerical tests carried out within the frameworks of this investigation demonstrated the qualitative and, partly, quantitative similarity of computation results and regularities observed in nature. The model sensitivity to the variation of some parameters is studied. The limits of model applicability are discussed and the directions of further research are proposed.  相似文献   

13.
It is shown that the influence of coherence of radiometeorological parameters on errors in their sample statistical characteristics must be taken into account. Formulas are proposed for estimating errors in calculating the mean and standard deviations of radiometeorological parameters with consideration of their coherence. It is shown that these errors under particular conditions may be 1.5 to 2 times as large as those calculated without taking into account their coherence.  相似文献   

14.
The problem of runoff prediction taking into account the possible climate change is considered using the Bayesian approach. The proposed technique is applied to the probabilistic forecasting of minimum runoff variations on the rivers of the Volga River basin.  相似文献   

15.
A hypothesis of the functional similarity of characteristics of natural processes forming a united physiographic process is theoretically justified and statistically verified using the time series of the data of microclimatic observations. This unity is manifested locally in time and is transformed into a new system of relations at changing background conditions of environment. The proposed computation scheme allows taking into account and identifying the persistent indicators of environmental state and the discrete moments of their variations using the method of rolling regression. The symmetry of processes is achieved by minimizing the residuals of functional relations of climatic characteristics derived by eliminating background impact. Proposed is a model of the genetic basis of the interdependence of natural processes based on the results of the data analysis and the formulae of the Legendre transform.  相似文献   

16.
为加快碳达峰、碳中和进程,中国正探索碳总量控制制度,而省域碳配额分配是落实总量控制目标的重要抓手。从分配准则、分配方法和分配结果3个环节对关于中国省域碳配额分配的研究开展综述。结果表明,兼顾公平和效率原则是各方研究共识,但对于公平原则的解读和测度尚存争议。指标法和优化法在省域碳配额分配中被广泛采用,前者能兼顾多方利益,后者能提升分配效率;混合法因具备多方法优势而具有较大发展潜力;博弈法因缺乏透明度而较为罕见。既有分配结果对各省分配的减排责任与各省实情间尚有差距,并仅关注某一特定年份当期或者某一时间区间内累计的碳配额分配,缺乏对逐年碳配额分配的关注。建议后续研究进一步关注兼顾公平与效率、考虑区域异质性与消费端排放责任、采用多方法组合、兼容个案特殊性的跨期动态分配方法学的构建过程。  相似文献   

17.
Presented are the quantitative estimates of the contribution of satellite data to the creation of reliable and accurate forecasts of convective events. Estimates are obtained by means of comparing the skill scores, reliability, and accuracy of forecasts of separate local and hardly predictable convective weather phenomena taking and not taking account of the satellite information.  相似文献   

18.
Developed is a new mechanism of photochemical reactions taking account of the dipole interaction between the molecules and the ??sharp?? inhomogeneities of electrified ice crystals in polar stratospheric clouds. This mechanism enables to explain the ozone depression formation during the winter-spring period in the polar stratosphere.  相似文献   

19.
Summary  The Bowen Ratio-Energy Balance (BREB) and the aerodynamic method were used to estimate turbulent fluxes of sensible and latent heat flux over an irrigated agricultural area (IAA) and over two dry agricultural areas (DAA1 and DAA2). These turbulent fluxes were analysed and particular attention paid to two specific areas. First, a quantitative analysis of sensible and latent heat fluxes obtained by the BREB method was carried out, taking into account different soil type, vegetation and surface conditions. The results showed that in IAA latent heat flux was higher than sensible heat flux, except in summer months, while in DAA1 and DAA2, sensible heat flux was higher except in the months when the vegetation was at the stage of maximum development. Second, sensible and latent heat fluxes estimates from the BREB method were compared with those obtained from the aerodynamic method. In this comparison factors such as soil type, soil vegetation cover, homogeneity or inhomogeneity of terrain and mesoscale effects such as orography and wind patterns were taken into account. The results show that in conditions of light wind, the two methods only concur if the condition of horizontal homogeniety is fulfilled. The influence of inhomogeneity seems to decrease and agreement between methods improves, if the wind is stronger and the effects of meso and synoptic scales are predominant. Received May 18, 1999/Revised March 15, 2000  相似文献   

20.
The methods are presented of agrometeorological forecasting of winter and spring grain crops for the district, all types of farm units, and field taking account of the regional crop forecast, weather conditions, cereal cropping technologies, and soil cultivation level. The additional yields of winter and spring wheat and spring barley and oat are developed depending on the soil cultivation level, summertime soil moistening, and doses of mineral fertilizers. The method tested on the basis of independent data demonstrated that the accuracy of such forecasts is 83–99% for the fields with intensive cultivation technology and 80% for the farm units.  相似文献   

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