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1.
本文根据非线性地面层模式(Shahawi,1983)建立了一种计算蒸发的空气动力学方法,能计算陆地和水面蒸发率E。根据导出关系计算出的蒸发量受S的影响,S是一个容易得到的系数,它是风速、大气稳定度、测量高度、表面粗糙度、大气压和空气密度的综合体现。导出方程的结果和实测值之间的比较研究表明本文提出的方法相当准确和有效。  相似文献   

2.
水面蒸发敏感因素的判断,对于干旱区水资源的规划与利用具有重要指导意义。本文以新疆塔里木河下游铁干里克气象站资料为例,对研究区水面蒸发影响因素进行分析。文章首先采用熵值法对水面蒸发进行敏感性分析,在此基础上运用灰色关联分析法进行验证。结果表明:温度、风速、日照时数这三因素对水面蒸发最为敏感;基于熵值法的敏感因素研究结果与灰色关联分析的结果基本一致,尤其在主要影响因素的判别上。研究结果干旱区水资源规划与利用提供了一种新方法和新思路。  相似文献   

3.
我国蒸发力计算的气候学方法   总被引:12,自引:1,他引:12  
本文根据我国的具体情况,利用10个大型蒸发池自由水面蒸发的实测资料,对计算水面蒸发力的彭曼公式作了修订。修正后的彭曼公式可用于我国水面蒸发力的计算;乘以合适的折算系数和作物系数,还可用来估算我国的自然蒸发力和农田可能蒸散。  相似文献   

4.
车尔臣河流域水面蒸发折算系数分析   总被引:2,自引:0,他引:2  
根据车尔臣河流域且末水文站1991-2004年间,20cm口径小型蒸发器与E601型蒸发器同期观测资料,估算了20cm小型蒸发器对E601型蒸发器的蒸发折算系数,分析了其变化特征,并将其与库尔勒市及我国新蒙区年水面蒸发折算系数进行了对比.结果表明,车尔臣河流域冻结期(10月一次年3月)的水面蒸发虽然微弱,但不能忽略,水面蒸发折算系数在非冻结期呈先增后减趋势,年际变化较小.该结果可供车尔臣河流域水量平衡研究、水资源评价、生态需水计算时参考.  相似文献   

5.
利用小型蒸发器观测水面蒸发量的几个问题   总被引:2,自引:0,他引:2  
裴步祥  邹耀芳 《气象》1989,15(6):48-51
本文利用广州蒸发实验站的水面蒸发量和气象要素的观测资料,计算了小型蒸发器的折算系数及其变异系数等;得出小型蒸发器与标准蒸发器月蒸发量的回归方程,以及计算水面蒸发量的经验公式。对上述观测和计算方法的结果进行了比较。并就气象台站的水面蒸发观测工作提出了建议。  相似文献   

6.
水面蒸发敏感因素的判断,对于干旱区水资源的规划与利用具有重要指导意义。文章以新疆塔里木河下游铁干里克气象站2005年资料为例,对研究区水面蒸发影响因素进行分析。采用熵值法对水面蒸发进行敏感性分析,并与关联分析法分析结果进行对比。结果表明:在塔里木河下游铁干里克地区,温度与风速二因素对水面蒸发影响最为敏感;基于熵值法的敏感因素研究结果与关联分析的结果基本一致。  相似文献   

7.
土壤含水量对蒸散的影响及其日蒸发模型   总被引:2,自引:0,他引:2  
根据土面与水面蒸发比(土水面蒸发比)与土壤含水量的关系,土水面蒸发比的日变化过程,以及毛管持水量和最低土壤含水量等数据,用加权平均法建立日蒸发模型。利用模型,由已知土壤含水量,可估测其前后若干天的土壤含水量。  相似文献   

8.
目前,测定蒸发力还存在许多经济和技术上的困难,所以现在多采用气候学方法计算。彭曼综合法是其中最好的方法之一。但因彭曼公式中系数的确定是经验性的,具有局地性,直接应用于我国蒸发力的计算误差较大。本文利用我国10个蒸发实验站水面蒸发实测资料作为检验标准,逐项修正彭曼公式中各物理力量的系数,建立了适合我国实  相似文献   

9.
水面蒸发敏感因素的判断,对于干旱区水资源的规划与利用具有重要指导意义。文章以新疆塔额盆地内的塔城市气象站1981—2010年资料为例,采用敏感系数法对研究区多年月均水面蒸发影响因素进行敏感性分析,并与关联分析法分析的结果对比。结果表明:在塔额盆地内,温度与水汽压二因素对水面蒸发影响最为敏感;基于敏感系数法的敏感因素研究结果与关联分析的结果基本一致,尤其在主要影响因子的判定上。  相似文献   

10.
丘陵地区面雨量计算方法及应用   总被引:5,自引:0,他引:5  
根据高斯权重客观分析原理,在考虑了流域内各地的降水气候差异和地形分布特点的基础上,找出一种适合于丘陵地区的面雨量计算方法。并将该方法计算的面雨量与泰森多边形法进行比较,研究了这两种计算方法的优缺点;此外,还研究了面雨量与流域的洪涝灾害的关系。结果表明,两者关系非常密切,流域面雨量的变化能较好地反映未来洪水的变化趋势。  相似文献   

11.
水面蒸发量敏感因素的判断,对于干旱区水资源规划利用具有重要的指导意义。本文以新疆尉犁县为例,对水面蒸发量影响因素进行分析。文章首先采用偏最小二乘回归法建立了水面蒸发量模型,在此基础上运用偏导数法分析了水面蒸发量对各影响因素的敏感性。结果表明:偏最小二乘回归模型具有较高的精度,不仅能够定量预测水面蒸发量,而且能够从机理上解释各影响因素对蒸发量的影响;风速、温度、水汽压这三因素对水面蒸发量最为敏感。上述模型为研究干旱区水资源利用提供了一种新方法和新思路。  相似文献   

12.
针对目前气象水文部门普遍采用的超声波蒸发传感器测量精度只有1.5mm且测量时易受环境因素影响的问题,提出了基于磁致伸缩位移测量技术,研制出一种高精度的测量装置,实现对水面蒸发量的自动测量,其测量精度可以达到0.1mm,同时给出了有关实现电路。通过在自动气象站中应用该装置进行为期6个月的蒸发量自动测量,并将自动测量数据和人工观测数据进行对比,验证了磁致伸缩技术在实现蒸发量的高精度自动化测量方面的可行性。在气象水文部门,可以使用该装置代替超声波蒸发传感器,得到精度更高、稳定性更好的蒸发量测量结果。  相似文献   

13.
文章根据新疆尉犁县气象站2008年4月至10月非结冰期水面蒸发量及相关常规气象观测资料,利用灰色关联分析法研究了不同尺度下各气象要素对水面蒸发量的影响程度。结果表明:在不同计算尺度下,水汽压、相对湿度与日照时数这三气象因素的影响程度排序无变化,说明计算尺度对其影响较小;温度(包括平均气温、最高气温与最低气温)与风速因素对蒸发量的影响程度随着研究尺度的变化而变化,其中平均温度与平均风速这两因素随着研究尺度的增大而影响程度随之增大;构成研究区域水面蒸发主要影响因素的是温度因素(包括平均气温、最高气温与最低气温)与风速因素。研究结果为区域水资源的规划、优化调度与管理提供了重要参考。  相似文献   

14.
短时段水面蒸发量计算方法的选择   总被引:4,自引:0,他引:4  
闵骞 《气象》1994,20(10):36-39
分别采用折算数法,彭曼公式法,道尔顿公式法计算都昌蒸发站旬与日短时段水面蒸发量,比较表明,用道尔顿公式计算短时段水面蒸发量的误差最小,彭曼公式次之,折算系数法的误差最大,不宜作短时段水面蒸发量的计算。  相似文献   

15.
This paper examines several prominent thermodynamic and dynamic factors responsible for the meridional and vertical warming asymmetries using a moist coupled atmosphere–surface radiative transportive four-box climate model. A coupled atmosphere–surface feedback analysis is formulated to isolate the direct response to an anthropogenic greenhouse gas forcing from individual local feedbacks (water vapor, evaporation, surface sensible heat flux, and ice-albedo), and from the non-local dynamical feedback. Both the direct response and response to water vapor feedback are stronger in low latitudes. The joint effect of the ice-albedo and dynamical greenhouse-plus feedbacks acts to amplify the high latitude surface warming whereas both the evaporation and dynamical greenhouse-minus feedbacks cause a reduction of the surface warming in low latitudes. The enhancement (reduction) of local feedbacks in high (low) latitudes in response to the non-local dynamic feedback further strengthens the polar amplification of the surface warming. Both the direct response and response to water vapor feedback lead to an increase of lapse rate in both low and high latitudes. The stronger total dynamic heating in the mean state in high latitudes is responsible for a larger increase of lapse rate in high latitudes in the direct response and response to water vapor feedback. The local evaporation and surface sensible heat flux feedbacks reduce the lapse rate both in low and high latitudes through cooling the surface and warming the atmosphere. The much stronger evaporation feedback leads to a final warming in low latitudes that is stronger in the atmosphere than the surface.  相似文献   

16.
We performed special experimental and theoretical research concerning the energy--mass exchange process in shallow waters, which took into account the influence of the basin depth on the evaporation and sensible heat exchange. Data was obtained from deep water basins, as well as from shallow waters, at an open sea, as well as in its coastal zone. A new parameterization model of evaporation and friction velocity from shallow water surfaces under different wind velocities was investigated. Results of models and measurements of the energy/mass exchange intensity of a small shallow lake (LITFASS-experiments) were compared. The validation of these models with the eddy-covariance measurements of the LITFASS-98 and LITFASS-2003 experiments showed good results for the wind sector, with good fetch conditions. Therefore, the models examined may be used for calculating the evaporation of lakes where a standard data set of wind velocity, air and water temperature, air moisture and the depth of the lake is available. It should be remembered that in a coastal zone the roughness of the water surface is transformed and therefore there are additional calculation difficulties for the intensity of the energy-mass exchange. Based on our experimental data of the basin depth influence on the water-atmosphere exchange, a new model for the calculation of the energy-mass exchange in a coastal zone was developed. Our new model in combination with the empirical dependence for the calculation of the energy-mass exchange in a coastal zone allows calculation of the momentum, heat and humidity fluxes values at different distances from a shore.  相似文献   

17.
Estimation of evaporation is important for water planning, management, and hydrological practices. There are many available methods to estimate evaporation from a water surface, comprising both direct and indirect methods. All the evaporation models are based on crisp conceptions with no uncertainty element coupled into the model structure although in daily evaporation variations there are uncontrollable effects to a certain extent. The probabilistic, statistical, and stochastic approaches require large amounts of data for the modeling purposes and therefore are not practical in local evaporation studies. It is therefore necessary to adopt a better approach for evaporation modeling, which is the fuzzy sets and adaptive neural-based fuzzy inference system (ANFIS) as used in this paper. ANFIS and fuzzy sets have been evaluated for its applicability to estimate evaporation from meteorological data which is including air and water temperatures, solar radiation, and air pressure obtained from Automated GroWheather meteorological station located near Lake E?irdir and daily pan evaporation values measured by XVIII. District Directorate of State Hydraulic Works. Results of ANFIS and fuzzy logic approaches were analyzed and compared with measured daily pan evaporation values. ANFIS approach could be employed more successfully in modeling the evaporation process than fuzzy sets.  相似文献   

18.
近50年鄱阳湖水面蒸发变化特征及原因分析   总被引:2,自引:0,他引:2  
利用康山、棠荫、都昌、星子、湖口水文、气象资料,应用器测折算法和气候模式法,确定鄱阳湖1955—2004年年、月水面蒸发量,并对近50 a的水面蒸发变化特征进行了分析,对影响水面蒸发的温度、湿度、风速等主要因子的变化进行了模拟计算。结果表明,除5月外的各月蒸发量及年蒸发量均呈减少趋势,湖区气温升高、湿度增大是造成水面蒸发减少的根本原因,与温室效应密切相关,是对大范围气候变化的同步响应。  相似文献   

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