摘要:

Unlike traditional statistical methods, a mathematical model is used to solve the problem of the long-term prediction of mountainous river runoff. The paper describes the structure of a basic model and ways of numerical presentation of macroscale rainfall fields in mountains as well as the computation of their parameters in conditions with complex relief and lack of information. The encouraging results and estimates of forecasts are discussed.

ISSN:0262-6667    

DOI:10.1080/02626669009492453

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The present paper is a brief report on a three-year research project carried out for the Federal Ministry of Agriculture and Forestry in Vienna, Austria. The results concerning the problems of precipitation enhancement by terrain-induced vertical motion are a first step towards new considerations regarding Probable Maximum Floods (PMF). For an Alpine country like Austria, the development of a hierarchy of concepts, using deterministic model physics and a digital terrain representation, appeared appropriate. The basic features of the model are consistent extensions of WMO recommendations.

ISSN:0262-6667    

DOI:10.1080/02626669009492454

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Atmospheric concentrations of carbon dioxide (CO2) may double during the next century, causing changes in the Earth's climate. Warming of up to 4°C, slight cooling, and 10% changes in precipitation have been projected. Researchers have studied the possible impacts these changes may have on various aspects of the hydrological cycle, but little emphasis has been placed on snow accumulation and melt. In this study, the effects of climatic change on streamflow from a snowmelt-dominated basin in southwestern Montana, USA, are investigated. The National Weather Service River Forecast System model (NWSRFS) was first calibrated using data for the 1973–1984 period. Daily temperature and precipitation values were then changed, and the model ran again to assess the effects on snowpack and streamflow of some possible climatic changes. Results indicate that streamflow may vary by from −22 to +45% depending on the combination of climatic changes imposed.

ISSN:0262-6667    

DOI:10.1080/02626669009492455

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

An analysis of a series of chalk samples from the Lublin coal basin reveals that its matrix is a very porous but only slightly permeable porous medium; its water reserves are hardly susceptible to gravity drainage. The interconnected porosity of the chalk matrix diminishes with depth, probably because of the increase in lithostatic pressure.

ISSN:0262-6667    

DOI:10.1080/02626669009492456

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

This paper attempts to search for a suitable structure of a monthly water yield model applicable for seasonally snow-covered mountainous catchments located in a semiarid area. In this respect several model structures based on a soil water balance concept were compared. The main distinction between the different structures was made by the inclusion of either a linear or a nonlinear transformation element for the conversion of overland flow or baseflow into total runoff. A combined water balance model having two main elements, a soil storage element generating excess water, and a transformation element conceptualized by a linear storage-discharge relationship, was found to be the most accurate.

ISSN:0262-6667    

DOI:10.1080/02626669009492457

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

This paper analyses a number of aspects related to the estimation of the design flood for a dam. A new approach to the estimation of the probable maximum precipitation (PMP) is described which takes advantage of the spatial variability of precipitation by using radar-derived distributed rainfall measurements. Procedures which utilize storm transposition and storm maximization are introduced to estimate the probable maximum flood (PMF) and are compared with regionalized statistical methods based upon the Wakeby and generalized extreme value distributions.

ISSN:0262-6667    

DOI:10.1080/02626669009492458

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669009492459

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669009492460

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669009492461

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669009492462

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor