福建省近50a降水趋势及区域变化特征   总被引：2，自引：0，他引：2  

吴滨 《台湾海峡》2005,24(4):440-447

本文应用趋势分析方法分析了福建省35个代表站1961～2003年年、季降水的变化规律．结果表明全年、春季、夏季全省降水以正的趋势为主，而雨季降水以负趋势为主，秋冬季趋势不明显．其后应用旋转主因子分析方法对年、季降水进行区域性分析，结果表明全省降水变化主要以南北向变化为主，东西向为次，同时给出了各季具体的分区范围．最后选取4个代表站进行降水的年代际变化分析．  相似文献   

舟山市一次冬季暴雨、大风天气过程分析     

张伟红 《海洋预报》2006,23(Z1):98-103

应用卫星云图、常规观测资料及T213数值分析产品,分析了2004年12月3~5日发生在浙江东部地区的暴雨和舟山市沿海的大风过程。分析结果表明:这次天气过程是由台风倒槽和冷空气及深厚的高空槽共同作用引起的;台风环流引起的东南低空急流为暴雨区输送了大量的水汽和不稳定能量;冷空气的侵入加上深厚的高空槽引起的低空辐合、中高层辐散,促使了东海低压的剧烈发展,产生了猛烈的大风。  相似文献   

上海沿岸天文潮与风暴潮非线性相互作用的数值研究   总被引：10，自引：0，他引：10  

端义宏  秦曾灏 《海洋与湖沼》1997,28(1):80-87

运用二维非线性风暴潮，天文潮和联合水位模型８次不同路径的热带气旋引起的上海地区天文潮与风暴潮的非线性相互作用进行了数值研究，讨论了天文潮气与风暴潮非线性相互作用引起的增水特征，分析了控制方程中各非线性项对天文潮与风暴晨线性相互作用引起水位变化的贡献，研究表明，考虑天文潮与风暴的非线性相互作用后，使风暴潮和水位的数值模拟结果得到了改善，非线性底摩擦在控制天文潮和风暴潮非线性相互作用中起重要的作用。而  相似文献   

极坐标变换变边界模型及其应用   总被引：6，自引：1，他引：6  

史峰岩  孙文心 《海洋与湖沼》1995,26(4):369-376

Ｊｏｈｎｓ变边界模型用于海湾海域风暴潮漫滩计算是，由于岸界变曲较大，而影响了计算的稳定性和精度，本文针对这个问题，导出了极坐标下的连续移动边界模型，从而改善了对岸界弯曲较大海域的风暴潮漫滩计算，通过对１９６９年黄河口沿岸一带水域风暴潮漫滩的模拟，证明这种极坐标变边界模型用于海湾海域的风暴潮漫滩计算，优于Ｊｏｈｎｓ变边界模型。  相似文献   

0518号台风"达维"风暴潮分析     

王青颜  石海莹 《海洋预报》2007,24(1):62-68

2005年9月26日凌晨4时,32年来最强的台风“达维”在海南省万宁市山根镇沿海地区登陆。“达维”一路横扫,肆虐全省18市县,重创海南,直接经济总损失达116.47亿元。本文对这次台风的风暴潮特点及其成因进行了较深入的分析,初步探讨灾情分布,为今后该类台风风暴潮预报积累经验及防灾减灾提供基础资料依据。  相似文献   

渤海海流概况及其输沙作用初析     

顾玉荷  修日晨 《海洋科学进展》1996,(1)

本文讨论了渤海及黄河口附近海域的海洋动力状况，潮流和风暴急流是输送黄河入海泥沙的主要动力。  相似文献   

海洋自动监测系统设备的安装     

张齐  王强 《海洋技术学报》2001,20(1):65-68

本文简述了自动监测系统现场安装的重要性，提出了设备安装的检查，现场的准备，及设备的安装方法和注意事项。  相似文献   

Impact of lithology and soil properties on abandoned dryland terraces during the early stages of soil erosion by water in south‐east Spain          下载免费PDF全文

Carlos Martínez‐Hernández  Jesús Rodrigo‐Comino  Asunción Romero‐Díaz 《水文研究》2017,31(17):3095-3109

Soil erosion by water in abandoned dry terraces is one of the most important environmental problems in semiarid areas, enhancing biological degradation and reducing possible resources that can be obtained. However, little is known about the effects of the types of lithology and soil properties on the early stages of soil erosion. Therefore, the main aim of this research was to assess the effect of different lithologies (marls, limestones, and metamorphic—phyllites, schists, and greywackes—materials) and soil properties on the early stages of soil erosion by water in abandoned dry terraces, compared with similar terraces still in agricultural use. Soil analyses (texture, aggregate stability, and bulk density) and 22 rainfall simulations were carried out under dry conditions. During the experiments, local inclination, vegetation and stone cover, total organic matter, and antecedent soil moisture were also quantified. The results showed that the highest soil loss (41.41 g/m² in cultivated plots and 17.05 g/m² in the abandoned plots) and runoff (3.79 L/m² in the abandoned plot) occurred on marl substrata. Marls also showed the shallowest infiltration front (9 cm) and lowest infiltration rate (4.3 cm/min). Limestones and, especially, metamorphic areas, showed a lower degree of soil erosion, higher infiltration rates, and deeper infiltration fronts.  相似文献   

Predictability of stemflow in a species‐rich tropical forest          下载免费PDF全文

Alexander Zimmermann  Magdalena Uber  Beate Zimmermann  Delphis F. Levia 《水文研究》2015,29(23):4947-4956

Numerous studies investigated the influence of abiotic (meteorological conditions) and biotic factors (tree characteristics) on stemflow generation. Although these studies identified the variables that influence stemflow volumes in simply structured forests, the combination of tree characteristics that allows a robust prediction of stemflow volumes in species‐rich forests is not well known. Many hydrological applications, however, require at least a rough estimate of stemflow volumes based on the characteristics of a forest stand. The need for robust predictions of stemflow motivated us to investigate the relationships between tree characteristics and stemflow volumes in a species‐rich tropical forest located in central Panama. Based on a sampling setup consisting of ten rainfall collectors, 300 throughfall samplers and 60 stemflow collectors and cumulated data comprising 26 rain events, we derive three main findings. Firstly, stemflow represents a minor hydrological component in the studied 1‐ha forest patch (1.0% of cumulated rainfall). Secondly, in the studied species‐rich forest, single tree characteristics are only weakly related to stemflow volumes. The influence of multiple tree parameters (e.g. crown diameter, presence of large epiphytes and inclination of branches) and the dependencies among these parameters require a multivariate approach to understand the generation of stemflow. Thirdly, predicting stemflow in species‐rich forests based on tree parameters is a difficult task. Although our best model can capture the variation in stemflow to some degree, a critical validation reveals that the model cannot provide robust predictions of stemflow. A reanalysis of data from previous studies in species‐rich forests corroborates this finding. Based on these results and considering that for most hydrological applications, stemflow is only one parameter among others to estimate, we advocate using the base model, i.e. the mean of the stemflow data, to quantify stemflow volumes for a given study area. Studies in species‐rich forests that wish to obtain predictions of stemflow based on tree parameters probably need to conduct a much more extensive sampling than currently implemented by most studies. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Assessment of rainfall spatial variability and its influence on runoff modelling: A case study in the Brue catchment,UK          下载免费PDF全文

Jun Zhang  Dawei Han 《水文研究》2017,31(16):2972-2981

This study explores rainfall spatial variability and its influence on runoff modelling. A novel assessment scheme integrated with coefficient of variance and Moran's I is introduced to describe effective rainfall spatial variability. Coefficient of variance is widely accepted to identify rainfall variability through rainfall intensity, whereas Moran's I reflects rainfall spatial autocorrelation. This new assessment framework combines these two indicators to assess the spatial variability derived from both rainfall intensity and distribution, which are crucial in determining the time and magnitude of runoff generation. Four model structures embedded in the Variable Infiltration Capacity model are adopted for hydrological modelling in the Brue catchment of England. The models are assigned with 1, 3, 8, and 27 hydrological response units, respectively, and diverse rainfall spatial information for 236 events are extracted from 1995. This study investigates the model performance of different partitioning based on rainfall spatial variability through peak volume (Q_p) and time to peak (T_p), along with the rainfall event process. The results show that models associated with dense spatial partitioning are broadly capable of capturing more spatial information with better performance. It is unnecessary to utilize models with high spatial density for simple rainfall events, though they show distinct advantages on complex events. With additional spatial information, Q_p experiences a notable improvement over T_p. Moreover, seasonal patterns signified by the assessment scheme imply the feasibility of seasonal models.  相似文献