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1.
Abstract The analysis of the exchanges of vapour and heat above a small water table, situated in the middle of a more or less dry region, leads them to be expressed in function of the thermic and hydric changes of the environment, by which the measured, screened data are influenced. This analysis allows us,—among other results,—to observe the variation from simple to the double of the evaporation. This has come to evidence already in cases when the evaporating surface diminishes. The application was carried out under two exceedingly different climates: in a Sahelian zone, on a pan type “Colorado”, situated in the middle of a bare surface, with very poor evaporation; and in an equatorial zone, on a “Colorado” pan, in the center of a humid zone, where the vegetation could dispose of water in sufficient quantity. The results confirm the hypothesis set up, and allow us to take into consideration the use of the pans corrected data for expressing the potential evaporation. 相似文献
2.
ABSTRACT From data obtained at stations set up in Chad, the Central African Republic and Congo-Brazzaville, stretching from the desert to the equatorial zone, it has been possible to compare measurements of evapotranspiration and of evaporation with results obtained by using the energy-balance method. Several difficulties arise in these comparisons since the scale of the measurements (small evaporating surfaces) is generally different from that of the climatic characteristics on which evaporation is dependent. After proposing a model to resolve this problem and fitting the empirical coefficients of Penman's formula, the author has applied this formula to some results derived for stations in Congo-Brazzaville; the potential evapotranspiration calculated in this way is in good agreement with water balance data. At these stations the evapotranspiration energy may be a constant percentage of global short-wave radiation. Finally, the energy-balance method has been used at Brazzaville to measure the actual evapotranspiration over grass during the dry season. The result is that actual and potential evapotranspiration were found to be closely related. These results indicate the importance of solar readiation in the field of hydrometeorology. 相似文献
3.
《水文科学杂志》2013,58(6)
Abstract Abstract Evaporation is one of the fundamental elements in the hydrological cycle, which affects the yield of river basins, the capacity of reservoirs, the consumptive use of water by crops and the yield of underground supplies. In general, there are two approaches in the evaporation estimation, namely, direct and indirect. The indirect methods such as the Penman and Priestley-Taylor methods are based on meteorological variables, whereas the direct methods include the class A pan evaporation measurement as well as others such as class GGI-3000 pan and class U pan. The major difficulty in using a class A pan for the direct measurements arises because of the subsequent application of coefficients based on the measurements from a small tank to large bodies of open water. Such difficulties can be accommodated by fuzzy logic reasoning and models as alternative approaches to classical evaporation estimation formulations were applied to Lake Egirdir in the western part of Turkey. This study has three objectives: to develop fuzzy models for daily pan evaporation estimation from measured meteorological data, to compare the fuzzy models with the widely-used Penman method, and finally to evaluate the potential of fuzzy models in such applications. Among the measured meteorological variables used to implement the models of daily pan evaporation prediction are the daily observations of air and water temperatures, sunshine hours, solar radiation, air pressure, relative humidity and wind speed. Comparison of the classical and fuzzy logic models shows a better agreement between the fuzzy model estimations and measurements of daily pan evaporation than the Penman method. 相似文献
4.
ABSTRACTSourcing subsurface evaporation (Ess) into groundwater (Eg) and unsaturated zone (Eu) components has received little scientific attention so far, despite its importance in water management and agriculture. We propose a novel sourcing framework, with its implementation in dedicated post-processing software called SOURCE (used along with the HYDRUS1D model), to study evaporation sourcing dynamics, define quantitatively “shallow” and “deep” water table conditions and test the applicability of water table fluctuation (WTF) and “bucket” methods for estimation of Eg and Eu separately.For the “shallow” and “deep” water table we propose Eg?>?0.95Ess and Eg = 0 criteria, respectively. Assessment of the WTF method allowed sourcing of very small fluxes otherwise neglected by standard hydrological methods. Sourcing with SOURCE software was more accurate than the standard “bucket” method mainly because of greater flexibility in spatio-temporal discretization. This study emphasized the dry condition relevance of groundwater evaporation which should be analysed by applying coupled flow of heat, vapour and liquid water.
Editor D. Koutsoyiannis; Associate editor S. Kanae 相似文献
5.
Abstract A water balance model of Lake Victoria that can be used to assess rainfall from lake level, is derived. The model utilizes satellite estimates of rainfall directly over the lake. The model, initially derived and calibrated for the period 1956–1978, is reformulated here in such a way that all water balance terms except evaporation can be calculated from a combination of catchment rainfall and level of the lake. The reformulated model is validated and used to predict lake level fluctuations during the period 1931–1994. An error analysis is also performed. The model is then “inverted” to solve for mean rainfall conditions during various intervals of changing lake levels. For modern periods with known rainfall conditions, the error in model estimates is of the order of 1%. 相似文献
6.
Takeo Nakagawa 《地球物理与天体物理流体动力学》2013,107(1):287-301
Abstract New periodic vortices were observed during a rotating tank experiment, to be described. The peculiarities and the formation mechanism of the present vortices are based on observations. The vortices reach the complete form in stages, viz. laminar boundary layer growth, sinuous motion and rolling oscillation. After being formed, the vortices are shed periodically and the diameter of the vortices grows as they advance. The vortices appear when the flow over the concave semicircular wall, fixed in the rotating tank, is maintained by the shear stresses at the inner surface of the rotating tank. The vortices and the flow were visualized with thymol blue dye. 相似文献
7.
Vassilis Z. Antonopoulos Soultana K. Gianniou Athanasios V. Antonopoulos 《水文科学杂志》2013,58(14):2590-2599
ABSTRACTEvaporation is one of the most important components in the energy and water budgets of lakes and is a primary process of water loss from their surfaces. An artificial neural network (ANN) technique is used in this study to estimate daily evaporation from Lake Vegoritis in northern Greece and is compared with the classical empirical methods of Penman, Priestley-Taylor and the mass transfer method. Estimation of the evaporation over the lake is based on the energy budget method in combination with a mathematical model of water temperature distribution in the lake. Daily datasets of air temperature, relative humidity, wind velocity, sunshine hours and evaporation are used for training and testing of ANN models. Several input combinations and different ANN architectures are tested to detect the most suitable model for predicting lake evaporation. The best structure obtained for the ANN evaporation model is 4-4-1, with root mean square error (RMSE) from 0.69 to 1.35 mm d?1 and correlation coefficient from 0.79 to 0.92.
EDITOR M.C. AcremanASSOCIATE EDITOR not assigned 相似文献
8.
ABSTRACT Because of the late withdrawal of the Levantine lake waters and because of low relief the Eastern Romanian Plain was fragmented only by big alochthonous rivers (Ialomi?a, C?lm??ui and Buz?u). The tabular-like, 40–50-km-wide interfluve areas covered by loessoid deposits and eolian sands on the periphery are deprived of surface drainage which accounts for their present evolution. The major relief forms in these interfluves are depressions called in Romanian ‘crov’ (sink-holes) in the central areas and short valleys formed initially by erosion processes and now modelled by mechanical and chemical weathering at their periphery: in these depressions (sink-holes) and in the secondary valleys, peripheral to the interfluve areas, lakes had started to be formed. Because of the semiarid climate sink-hole lakes have an intermittent hydrological regime, whereas those located in the small fluviatile liman-type valleys, enjoy a permanent regime. By the absence of surface drainage, by the loss of significant amounts of water through evaporation and the degree of mineralization, these lakes fall within the group of salt lakes. In the past few years (since 1966 and especially since 1969) the level of these lakes has continually risen and the depressions formerly lacking water started being flooded by the rising of the piezometric level. An analysis was made of the water balance of the Amara-Ialomi?a lake to investigate this phenomenon. Level and evaporation recordings were made in the period 1956–1970. The findings revealed that the supply of underground water to the lake amounts to 47·3 per cent exceeding the water supply produced by the rains that fell on the surface of the lake (46·7 per cent). A close relationship was established (with a lapse of 8–12 months) between the surface supply of the basin (through rainfalls) and the flow of underground water to the lake. Extending the precipitation-induced level changes over a longer period (1896–1915 and 1921–1970) it was found that level increases are cyclic, as a direct consequence of the corresponding precipitation regime. 相似文献
9.
G. TSAKIRIS 《水文科学杂志》2013,58(5):437-447
Abstract The paper is concerned with the modelling of rainfall occurrence in continuous time. The Alternating Renewal Process is employed for the evaluation of probability distribution functions for total wet and dry periods over a homogeneous time interval (0, t). The derived general solution is simplified by assuming that the individual wet and dry intervals are random variables following an Erlang distribution, in particular an exponential distribution. Data on a continuous time scale from the Mikra Station in Greece are used to illustrate the proposed methodology. 相似文献
10.
Norina Andres Fernando Vegas Galdos Waldo Sven Lavado Casimiro Massimiliano Zappa 《水文科学杂志》2013,58(11):2043-2059
AbstractEstimating water resources is important for adequate water management in the future, but suitable data are often scarce. We estimated water resources in the Vilcanota basin (Peru) for the 1998–2009 period with the semi-distributed hydrological model PREVAH using: (a) raingauge measurements; (b) satellite rainfall estimates from the TRMM Multi-satellite Precipitation Analysis (TMPA); and (c) ERA-Interim re-analysis data. Multiplicative shift and quantile mapping were applied to post-process the TMPA estimates and ERA-Interim data. This resulted in improved low-flow simulations. High-flow simulations could only be improved with quantile mapping. Furthermore, we adopted temperature and rainfall anomalies obtained from three GCMs for three future periods to make estimations of climate change impacts (Delta-change approach) on water resources. Our results show more total runoff during the rainy season from January to March, and temporary storages indicate that less water will be available in this Andean region, which has an effect on water supply, especially during dry season.Editor Z.W. Kundzewicz; Associate editor D. Gerten 相似文献
11.
AbstractGroundwater of the Tertiary-Quaternary Formations in the Jeloula basin (Central Tunisia), together with rain and surface waters, were analysed to investigate the mineralization processes, the origin of the water and its recharge sources. The water samples present a large spatial variability of chemical facies which is related to their interaction with the geological formations. The main sources of the water mineralization are the dissolution of evaporitic and carbonate minerals and cation exchange reactions. Stable isotopes indicate that most groundwater samples originate from infiltration of modern precipitation. Surface water samples from small dam reservoirs show a 18O/2H enrichment, which is typical of water exposed to open-surface evaporation in a semi-arid region. Considerable data of 3H and 14C allow the qualitative identification of the present-day recharge that is probably supplied by infiltration of recent flood waters in the Wadi El Hamra valley, and by direct infiltration of meteoric water through the local carbonate outcrops.Editor D. Koutsoyiannis; Associate editor S. Faye 相似文献
12.
Abstract A dry pond is an urban drainage component designed to temporarily store stormwater runoff and to encourage infiltration of surface water to the subsurface layer. This paper investigates field measurement of a dry pond at Taiping Health Clinic, Perak, Malaysia that has been functioning well for five years. The pond has a surface area of 195 m2, maximum depth of 32 cm, and a storage capacity of 31.88 m3. The study focused on the infiltration functionality of the constructed dry pond and the results show that it has an average infiltration rate of 125 mm/h and dries up in 330 min after being filled to a depth of 31 mm. A public-domain hydrological model was then employed to simulate hydrographs of ponding and draining, the results of which matched observations with 86–98% accuracy. These results can lead to better understanding of the system and allow duplication of such a drainage design elsewhere. Editor D. Koutsoyiannis Citation Lai, S.H. and Mah, D.Y.S., 2012. Field investigation of a dry detention pond with underground detention storage. Hydrological Sciences Journal, 57 (6), 1249–1255. 相似文献
13.
M. G. Hodnett L. Pimentel da Silva H. R. da Rocha R. Cruz Senna 《Journal of Hydrology》1995,170(1-4):233-254
Evaporation and infiltration were compared for tropical rainforest and pasture, near to Manaus, Brazil from October 1990 to February 1992 using measurements of soil water storage over a depth of 2 m. The soil is a clayey oxisol of low water available capacity. In both of the dry seasons studied, the maximum change in soil water storage in the forest was 154 mm and in the pasture it was 131 and 112 mm. Similar behaviour of the soil water reservoir below forest and pasture in the wet season implied that differences in evaporation and drainage were small. In the dry season, soil water storage behaviour in the upper metre of the soil was similar but there were marked differences in the second metre. The pasture took up little water from below 1.5 m but the forest appeared to utilise all of the available water in the 2 m profile in both seasons.
The water balance of the 2 m profile showed that the pasture evaporation rate was equal to that of the forest until storage had decreased 80 mm from the maximum. There was then a decline in pasture evaporation rate to 1.2 mm day−1 as the storage decreased by a further 50 mm. In contrast, the forest uptake rate remained above 3.5 mm day−1 until storage had decreased 140 mm from the maximum (within 15 mm of the extraction limit), before declining abruptly to less than 1.5 mm day−1. There was strong evidence that the forest was able to abstract water from depths greater than 3.6 m.
Spatial variability of soil water storage was significantly greater beneath the pasture than beneath the forest, particularly following rainfall events in the dry season. This was largely the result of redistribution of rainfall as local surface runoff. There was no evidence of redistribution or runoff in the forest. 相似文献
14.
B. HENDERSON-SELLERS 《水文科学杂志》2013,58(4):363-367
ABSTRACT It is shown that a numerical model for predicting the depth time variation of water temperature in a fresh water lake or reservoir can be used also for prediction of water losses due to evaporation. The seasonal change in peak evaporation from summer (in small lakes) to winter (in large lakes) is satisfactorily simulated. 相似文献
15.
Shengli Huang Claudia Young Omar I. Abdul-Aziz Devendra Dahal Min Feng Shuguang Liu 《水文科学杂志》2013,58(7):1434-1444
AbstractHydrological processes of the wetland complex in the Prairie Pothole Region (PPR) are difficult to model, partly due to a lack of wetland morphology data. We used Light Detection And Ranging (LiDAR) data sets to derive wetland features; we then modelled rainfall, snowfall, snowmelt, runoff, evaporation, the “fill-and-spill” mechanism, shallow groundwater loss, and the effect of wet and dry conditions. For large wetlands with a volume greater than thousands of cubic metres (e.g. about 3000 m3), the modelled water volume agreed fairly well with observations; however, it did not succeed for small wetlands (e.g. volume less than 450 m3). Despite the failure for small wetlands, the modelled water area of the wetland complex coincided well with interpretation of aerial photographs, showing a linear regression with R2 of around 0.80 and a mean average error of around 0.55 km2. The next step is to improve the water budget modelling for small wetlands.Editor Z.W. Kundzewicz; Associate editor X. ChenCitation Huang, S.L., Young, C., Abdul-Aziz, O.I., Dahal, D., Feng, M., and Liu, S.G., 2013. Simulating the water budget of a Prairie Potholes complex from LiDAR and hydrological models in North Dakota, USA. Hydrological Sciences Journal, 58 (7), 1434–1444. 相似文献
16.
Abstract Under a sustainable groundwater development and quality management project over a semi-arid granite terrain, several rainwater harvesting structures were proposed based on geophysical investigations in the study area. In order to validate the site suitability and check the efficacy of the recommended recharge structures in terms of source sustainability, certain hydrological tests, such as infiltration studies, were conducted within the recharge area of these structures. Infiltration rate estimation using a double-ring infiltrometer normally results in an exponential decay relationship with high initial infiltration rate followed by gradual reduction until, ultimately, a stabilized rate is attained. In this paper, we present the results of infiltration tests conducted using a double-ring infiltrometer (under constant head condition) within the tank bed area of a proposed percolation tank site. The results showed unique features in the infiltration rate at different time intervals within the total experimental period: a staircase-like evolution with intermittent stabilization for a short duration. Based on the integrated approach of geophysical investigations, hydrological tests, and supported by physical evidence, the infiltration behaviour observed over the study area was considered to be due to the lithological stratification with different permeability and textural conditions. Citation Andrade, R. & Muralidharan, D. (2011) The influence of litho-stratification on the infiltrating water front in a granite terrain. Hydrol. Sci. J. 56(5), 907–915. 相似文献
17.
Josip Rubinić 《水文科学杂志》2013,58(10):1908-1924
AbstractVrana Lake in Dalmatia is a karstic kryptodepression connected to the nearby sea through the karstic subsoil and a canal. Due to interactions with the sea, lake water salinity increases greatly during severe dry periods, seriously endangering the ecosystem. Trend analysis (1961–2010) reveals a decrease in precipitation and surface inflow, but an increase in air temperature, and in sea and lake water levels. Lake inflow and water losses are only partially monitored. Average annual inflow from the monitored part of the catchment is 1722 m3 s-1, but total inflow is significantly greater; the average difference between total inflow and cumulative water losses is 3072 m3 s-1. The paper uses modelling to evaluate total inflow into the lake system, taking into consideration projected climate changes/variations till 2100 from the RegCM3 and ALADIN climate models. The analysis indicates marked decrease in discharge values by the end of this century, by as much as 60%.
Editor Z.W. Kundzewicz 相似文献
18.
《水文科学杂志》2013,58(4)
Abstract Abstract An annual water balance model of Lake Victoria is derived for the period 1925–2000. Regression techniques are used to derive annual inputs to the water balance, based on lake rainfall data, measured and derived inflows and estimated evaporation during the historical period. This approach acknowledges that runoff is a nonlinear function of lake rainfall. A longer inflow series is produced here which is representative of the whole inflow to the lake, rather than just from individual tributaries. The results show a good simulation of annual lake levels and outflows and capture the high lake level in 1997–1998. Climate change scenarios, from a recent global climate model experiment, are applied to the lake rainfall inflow series and evaporation data to estimate future water balances of the lake. The scenarios produce a potential fall in lake levels by the 2030s horizon, and a rise by the 2080s horizon. A discussion of the application of climate change data to this complex hydrological system is presented. 相似文献
19.
Anvar Kacimov 《水文科学杂志》2013,58(1):237-248
Abstract A tension-saturated water slug descends through a homogenous soil after a rainfall (irrigation) event and shrinks due to transpiration by a distributed root-sink and evaporation. The upper (drainage) and lower (imbibition) sharp fronts of the slug separate it from the superjacent and subjacent vadose zones, where water is immobile. In the slug, the hydraulic conductivity is constant according to the Green-Ampt model. The capillary pressures as well as effective porosities on the fronts are given (generally, different) constants that can be viewed as a kind of hysteresis. A volumetric sink models mild (no desaturation of the slug) soil water withdrawal by the plant roots. The sink intensity varies with the depth from the soil surface and with time. Mathematically, the hydraulic head is immediately expressed by double integration of a governing 1-D flow equation. The pressure and kinematic conditions on the fronts result in a Cauchy problem for a system of two ODEs, which is solved by computer algebra routines. Editor D. Koutsoyiannis Citation Kacimov, A. and Obnosov, U., 2013. Pseudo-hysteretic double-front hiatus-stage soil water parcels supplying a plant–root continuum: the Green-Ampt-Youngs model revisited. Hydrological Sciences Journal, 58 (1), 1–12. 相似文献
20.
Said S. Al-Ismaily Ali K. Al-Maktoumi Anvar R. Kacimov Said M. Al-Saqri Hamad A. Al-Busaidi Mansour H. Al-Haddabi 《水文科学杂志》2013,58(8):1779-1788
AbstractA pedological study of the reservoir bed of Al-Khoud Dam, Oman, revealed an unusual sedimentation pattern which evolved into an intricate composition of silt blocks surrounded by vertical cracks and horizontal layers filled with a “proppant” sand. The discovered soil morphology reflects the complex topology of water motion (infiltration–seepage–evaporation) through the sand-filled cracks/layers and blocks during both the rare flood events and ensuing periods of ponding, and the long, intervening dry periods. These naturally formed soils demonstrate an ability to preserve a large quantity of water inside the silty blocks at depths of 0.5 to 1.5 m, despite the high temperature and dryness of the topsoil. The hydrological optimality and “smartness” of these soils is attributed to the unique block-crack system. Natural, lush vegetation was found in adjacent zones of the reservoir bed, and acted as a footprint of the shallow “fractured perched aquifer”. Planted “ivy” (Convolvulaceae) in the vertical face of one pedon showed intensive growth without irrigation. Soil moisture content data confirmed the hydrological immobility of water in the blocks if not depleted by transpiration. The novel phenomena reported unveil the possible alteration of soil heterogeneity for optimization of the soil–water system in arid zone soils.
Editor D. Koutsoyiannis; Associate editor F.F. HattermannCitation Al-Ismaily, S.S., Al-Maktoumi, A.K., Kacimov, A.R., Al-Saqri, S.M., Al-Busaidi, H.A., and Al-Haddabi, M.H., 2013. Morphed block-crack preferential sedimentation in a reservoir bed: a smart design and evolution in nature. Hydrological Sciences Journal, 58 (8), 1779–1788. 相似文献