相关论文
2000 - Polymer Testing
Effect of temperature on water vapor transport through polymer membrane laminates

This paper determines the extent to which the water vapor transport properties of nine different polymer membranes and membrane/textile laminates are affected by temperature. A particular test method, the Dynamic Moisture Permeation Cell (DMPC), is ideally suited for this type of study, owing to its complete control over the humidity and gas flow rate on the two sides of the test sample, and the ability to control the temperature of the test system. This allows temperature-dependent effects to be separated from concentration-dependent effects on mass transfer phenomena. The DMPC permits the experimenter to explore the temperature dependence of the diffusion behavior at different points on the vapor sorption isotherm of the hydrophilic polymer component of a polymer film or membrane laminate. Temperature effects are shown to be much less important than concentration-dependent effects in a hydrophilic polymer layer. Observed changes in water vapor flux at different temperatures are primarily due to the relationship between temperature and the saturation vapor pressure of water, and not to intrinsic changes in polymer permeability.

2017 - Journal of hazardous materials
Estimation of nutrient discharge from the Yangtze River to the East China Sea and the identification of nutrient sources.

Based on a time-series dataset and the mass balance method, the contributions of various sources to the nutrient discharges from the Yangtze River to the East China Sea are identified. The results indicate that the nutrient concentrations vary considerably among different sections of the Yangtze River. Non-point sources are an important source of nutrients to the Yangtze River, contributing about 36% and 63% of the nitrogen and phosphorus discharged into the East China Sea, respectively. Nutrient inputs from non-point sources vary among the sections of the Yangtze River, and the contributions of non-point sources increase from upstream to downstream. Considering the rice growing patterns in the Yangtze River Basin, the synchrony of rice tillering and the wet seasons might be an important cause of the high nutrient discharge from the non-point sources. Based on our calculations, a reduction of 0.99Tg per year in total nitrogen discharges from the Yangtze River would be needed to limit the occurrences of harmful algal blooms in the East China Sea to 15 times per year. The extensive construction of sewage treatment plants in urban areas may have only a limited effect on reducing the occurrences of harmful algal blooms in the future.

2009 - Environmental pollution
Sorption of alkylphenols on Ebro River sediments: comparing isotherms with field observations in river water and sediments.

This study reports sorption isotherms of the endocrine disruptors nonylphenol (NP) and octylphenol (OP) in three sediment samples from the Ebro River basin (NE Spain), with organic carbon fractions (f(OC)) ranging from 0.0035 to 0.082 g(OC)g(-1). All isotherms were fitted to the Freundlich model with slightly nonlinear exponents ranging from 0.80 to 0.94. The solubility of the compounds as well as the organic carbon (OC) content had the strongest influences on the sorption behavior of these compounds. Comparison of the laboratory-spiked samples with the native contamination of NP of 45 water and concurrent sediment samples resulted in reasonable matches between both data sets, even though the lowest concentrations in the field were not completely reached in laboratory tests. This good agreement indicates that sorption laboratory data can be extrapolated to environmental levels and therefore the distribution of nonylphenol between sediments and water can be predicted with a precision of one order of magnitude. Furthermore, laboratory experiments with simultaneous loading of NP and OP revealed negligible competition for sorption sites at low concentrations.

2016 - The Science of the total environment
The Water Footprint as an indicator of environmental sustainability in water use at the river basin level.

One of the main challenges in water management is to determine how the current water use can condition its availability to future generations and hence its sustainability. This study proposes the use of the Water Footprint (WF) indicator to assess the environmental sustainability in water resources management at the river basin level. The current study presents the methodology developed and applies it to a case study. The WF is a relatively new indicator that measures the total volume of freshwater that is used as a production factor. Its application is ever growing in the evaluation of water use in production processes. The calculation of the WF involves water resources (blue), precipitation stored in the soil (green) and pollution (grey). It provides a comprehensive assessment of the environmental sustainability of water use in a river basin. The methodology is based upon the simulation of the anthropised water cycle, which is conducted by combining a hydrological model and a decision support system. The methodology allows the assessment of the environmental sustainability of water management at different levels, and/or ex-ante analysis of how the decisions made in water planning process affect sustainability. The sustainability study was carried out in the Segura River Basin (SRB) in South-eastern Spain. The SRB is among the most complex basins in Europe, given its special peculiarities: competition for the use, overexploitation of aquifers, pollution, alternative sources, among others. The results indicate that blue water use is not sustainable due to the generalised overexploitation of aquifers. They also reveal that surface water pollution, which is not sustainable, is mainly caused by phosphate concentrations. The assessment of future scenarios reveals that these problems will worsen if no additional measures are implemented, and therefore the water management in the SRB is environmentally unsustainable in both the short- and medium-term.

2013 - Earth System Dynamics Discussions
Hydrological cycle over South and Southeast Asian river basins as simulated by PCMDI/CMIP3 experiments

Abstract. We investigate how the climate models contributing to the PCMDI/CMIP3 dataset describe the hydrological cycle over four major South and Southeast Asian river basins (Indus, Ganges, Brahmaputra and Mekong) for the 20th, 21st (13 models) and 22nd (10 models) centuries. For the 20th century, some models do not seem to conserve water at the river basin scale up to a good degree of approximation. The simulated precipitation minus evaporation (P − E), total runoff (R) and precipitation (P) quantities are neither consistent with the observations nor among the models themselves. Most of the models underestimate P − E for all four river basins, which is mainly associated with the underestimation of precipitation. This is in agreement with the recent results on the biases of the representation of monsoonal dynamics by GCMs. Overall, a modest inter-model agreement is found only for the evaporation and inter-annual variability of P − E. For the 21st and 22nd centuries, models agree on the negative (positive) changes of P − E for the Indus basin (Ganges, Brahmaputra and Mekong basins). Most of the models foresee an increase in the inter-annual variability of P − E for the Ganges and Mekong basins, thus suggesting an increase in large low-frequency dry/wet events. Instead, no considerable future change in the inter-annual variability of P − E is found for the Indus and Brahmaputra basins.

2014 - Hydrology and Earth System Sciences
Hydrological drought forecasting and skill assessment for the Limpopo River basin, southern Africa

Ensemble hydrological predictions are normally obtained by forcing hydrological models with ensembles of atmospheric forecasts produced by numerical weather prediction models. To be of practical value to water users, such forecasts should not only be sufficiently skilful, they should also provide information that is relevant to the decisions end users make. The semi-arid Limpopo Basin in southern Africa has experienced severe droughts in the past, resulting in crop failure, economic losses and the need for humanitarian aid. In this paper we address the seasonal prediction of hydrological drought in the Limpopo River basin by testing three proposed forecasting systems (FS) that can provide operational guidance to reservoir operators and water managers at the seasonal timescale. All three FS include a distributed hydrological model of the basin, which is forced with either (i) a global atmospheric model forecast (ECMWF seasonal forecast system – S4), (ii) the commonly applied ensemble streamflow prediction approach (ESP) using resampled historical data, or (iii) a conditional ESP approach (ESPcond) that is conditional on the ENSO (El Nino–Southern Oscillation) signal. We determine the skill of the three systems in predicting streamflow and commonly used drought indices. We also assess the skill in predicting indicators that are meaningful to local end users in the basin. FS_S4 shows moderate skill for all lead times (3, 4, and 5 months) and aggregation periods. FS_ESP also performs better than climatology for the shorter lead times, but with lower skill than FS_S4. FS_ESPcond shows intermediate skill compared to the other two FS, though its skill is shown to be more robust. The skill of FS_ESP and FS_ESPcond is found to decrease rapidly with increasing lead time when compared to FS_S4. The results show that both FS_S4 and FS_ESPcond have good potential for seasonal hydrological drought forecasting in the Limpopo River basin, which is encouraging in the context of providing better operational guidance to water users.

2014 - Water Resources Management
Assessment of Future Water Scarcity at Different Spatial and Temporal Scales of the Brahmaputra River Basin

Climate change is one of the main driving forces that affect both the temporal and spatial variability of water availability. Besides climatic change, current demographic trends, economic development and related land use changes have direct impact on increasing demand for freshwater resources. Taken together, the net effect of these supply and demand changes has led to a growing water scarcity in major international river basins. The Brahmaputra River Basin is one of the most vulnerable areas in the world, as it is subject to combined effect of climate change and development pressures. A robust assessment of water scarcity considering both climatic and socio-economic changes is therefore vital for policy makers of the basin. In this study, we analyze future water scarcity of the Brahmaputra Basin in a geographically and temporally detailed manner, incorporating several novel approaches: (i) the application of consistent set of scenarios to estimate future water scarcity; (ii) estimation of water demand in terms of both water withdrawals and consumptive water use; (iii) comparison of water demand and availability on different temporal scales i.e., yearly, seasonal and monthly rather than only annual basis. (iv) assessment of groundwater recharge affected by climate change together with future demands for groundwater abstraction. Although the Brahmaputra Basin is one of the water abundant regions of the world, our analysis illustrates that during dry season water scarcity for the Basin will become more severe in the coming decades, which requires special attention to the decision makers of the authority.

2011
WATER VAPOR BARRIER PROPERTIES OF COATED AND FILLED MICROFIBRILLATED CELLULOSE COMPOSITE FILMS

Microfibrillated celluloses (MFCs) have mechanical properties sufficient for packaging applications, but lack in comparison to petroleum-based plastics in water vapor barrier properties. These properties can be modified by the use of mineral fillers, added within the film structure, or waxes, as surface coatings. In this investigation it was found that addition of fillers resulted in films with lower densities but also lower water vapor transmission rates. This was hypothesized to be due to decreased water vapor solubility in the films. Associated transport phenomena were described by the Knudsen model for diffusion but due to the limited incorporation of chemical factors in the model, accurate prediction of pore diameters for filled films was not possible. Modeling the filled-films with Fick’s equation, however, takes into account chemical differences, as observed by the calculated tortuosity values. Remarkably, coating with beeswax, paraffin, and cooked starch resulted in films with water vapor transmission rates lower than those for low density polyethylene. These coatings were modeled with a three-layer model which determined that coatings were more effective in reducing WVTR.

1996 - Water Science and Technology
Inventories of point and diffuse sources and estimated nutrient loads - a comparison for different river basins in central europe

A comparison of the estimated emissions (input) with the measured loads at monitoring stations (output) is presented for the large Rivers Rhine, Elbe and its main tributaries and for the River Warnow, a smaller river in the north-east part of Germany. The comparison shows that the discrepancies between the estimated emissions and the measured load is small for the Rhine and its main tributaries, Mosel, Neckar and Main. Large discrepancies were found for the Elbe and its main tributaries. For all investigated river systems a strong relationship exists between the quotient of measured nutrient load versus the estimated sum of point and diffuse emissions of nutrients and the areal specific runoff. A function is derived for the dependency of the sum of retention and/or losses in a river system on the specific runoff and the nutrient concentration in the river. The high accuracy of the estimated retention and/or losses within the different river basins offer the possibility to use these equations for a prediction of the emitted nutrients from measured nutrient load in similar rivers.

2004 - Marine pollution bulletin
Seasonal and annual loads of hydrophobic organic contaminants from the Susquehanna River basin to the Chesapeake Bay.

Water from the Susquehanna River was collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyl (PCB) congeners to estimate seasonal and annual riverine loads to the Chesapeake Bay. Temporal variations in the chemical loads resulted from the large changes in the water flow rates and in the particle-associated contaminant concentrations. Concentrations of PCBs and PAHs in river particles (ng/g) were twice as great as those in the northern Chesapeake Bay, indicating that the Susquehanna River is an important source of these contaminants to the bay. The river carries a majority of its hydrophobic organic contaminants (HOCs) in the particulate phase. During periods of high flow, large amounts of suspended particles in the river result in elevated HOC levels and increased loadings of these contaminants to the bay. From 1997 to 1998, 60% of the total annual HOC loading occurred in the early spring coincident with high river flows. The total PCB and PAH annual loadings from the Susquehanna River to the Chesapeake Bay were 76 and 3160 kg/year, respectively and 75% of the loaded organic contaminants were in the particulate phase. Principal component analysis of PAH and PCB congener patterns in the particles reveals that the river suspended particles were dominated by autochthonous production in the summer and by resuspended sediment and watershed erosion during the winter and early spring.

2012 - Environmental Earth Sciences
Morphometrical analysis of two tropical mountain river basins of contrasting environmental settings, the southern Western Ghats, India

The morphometric analysis of river basins represents a simple procedure to describe hydrologic and geomorphic processes operating on a basin scale. A morphometric analysis was carried out to evaluate the drainage characteristics of two adjoining, mountain river basins of the southern Western Ghats, India, Muthirapuzha River Basin (MRB) in the western slopes and Pambar River Basin (PRB) in the eastern slopes. The basins, forming a part of the Proterozoic, high-grade, Southern Granulite Terrain of the Peninsular India, are carved out of a terrain dominantly made of granite- and hornblende-biotite gneisses. The Western Ghats, forming the basin divide, significantly influences the regional climate (i.e., humid climate in MRB, while semi-arid in PRB). The Survey of India topographic maps (1:50,000) and Shuttle Radar Topographic Mission digital elevation data were used as the base for delineation and analysis. Both river basins are of 6th order and comparable in basin geometry. The drainage patterns and linear alignment of the drainage networks suggest the influence of structural elements. The Rb of either basins failed to highlight the structural controls on drainage organization, which might be a result of the elongated basin shape. The irregular trends in Rb between various stream orders suggest the influence of geology and relief on drainage branching. The Dd values designate the basins as moderate- to well-drained with lower infiltration rates. The overall increasing trend of Rl between successive stream orders suggests a geomorphic maturity of either basins and confirmed by the characteristic Ihyp values. The Re values imply an elongate shape for both MRB and PRB and subsequently lower vulnerability to flash floods and hence, easier flood management. The relatively higher Rr of PRB is an indicative of comparatively steeply sloping terrain and consequently higher intensity of erosion processes. Further, the derivatives of digital elevation data (slope, aspect, topographic wetness index, and stream power index), showing significant differences between MRB and PRB, are useful in soil conservation plans. The study highlighted the variation in morphometric parameters with respect to the dissimilarities in topography and climate.

2013 - Agricultural Water Management
Assessing the effects of water table depth on water use, soil salinity and wheat yield: Searching for a target depth for irrigated areas in the upper Yellow River basin

The irrigation districts of the upper Yellow River basin face a progressive reduction of water allocation and the need to apply water-saving practices due to increasing water scarcity. The adoption of such practices will lead to lower water tables, hopefully in conjunction with controlled soil salinity levels and improved crop yields. However, excessive water saving associated with excessive increase of the water table depth may decrease capillary rise and affect crop production. In view of understanding the related processes in Qingtongxia Irrigation District, the physically based agro-hydrological model, SWAP, was adopted to explore the response of soil water and solute dynamics, and crop yield to water table changes. With this purpose, SWAP was modified through the inclusion of a simplified crop growth module, a method of variable active-nodes, and a nonlinear osmotic head-dependent function for a better description of the effects of salinity stress on root water uptake. The model was calibrated and validated using wheat's experimental data from 2007 and 2008. Simulations of soil water content, salinity concentration, biomass, and crop yield fitted well with field observations. The calibrated model was then used to predict changes in crop yield, soil water dynamics and soil salinity considering scenarios with different groundwater depths and irrigation strategies. The present irrigation strategy favors salt leaching even when considering the increase of water table depth that results in small crop yield reduction (<6%) due to salt stress. The 80% and 60% reduced irrigation strategies led to increased soil salinity and, eventually, crop yield reductions of 6–14% and 13–21%, respectively, when the depth of the water table increased. A target groundwater depth of 1.0–1.5m is suggested to be optimal for wheat's growth season with the aim of maintaining crop yields under the present conditions.

2005 - Science in China Series D: Earth Sciences
Plausible impact of global climate change on water resources in the Tarim River Basin

Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Nino/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1n rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

2010 - Fuel and Energy Abstracts
Assessing the groundwater dynamics and impacts of water saving in the Hetao Irrigation District, Yellow River basin

Water resources allocated to the agricultural sector in the Yellow River basin are being reduced due to severe water scarcity and increased demand by the non-agricultural sectors. In large-scale irrigation districts, the application of water-saving practices, e.g., improving the canal system, using water-saving irrigation technology and adjusting cropping patterns, is required for the sustainable agricultural development and the river basin environmental equilibrium. Adopting water-saving practices leads to lowering the groundwater table and to controlling salinity impacts related to excessive irrigation. However, assessing the effects of water-saving practices on the groundwater system requires further investigation. The Jiefangzha Irrigation Scheme of the Hetao Irrigation District is used as a case study for analyzing the temporal and spatial dynamics of the groundwater table. A lumped parameter groundwater balance model has been developed with this purpose and to assess impacts of various water-saving practices. The model was calibrated with monthly datasets relative to the non-frozen periods of 1997-1999 and validated with datasets from 2000 to 2002. Results indicate that canal seepage and deep percolation account for respectively 48% and 44% of the annual groundwater recharge. Groundwater discharge by direct evaporation and plant roots uptake represents 82% of the total annual groundwater discharge. After validation, the model was applied to assess the impacts of various canal and farm irrigation water-saving practices. It was observed that improvements in the canal system (e.g., canal lining, upgrading the hydraulic regulation and control structures, improving delivery schedules) might lower the groundwater table by 0.28-0.48Â m, depending upon the level of implementation of these measures. Higher declines of the groundwater table are predicted when water-saving technologies are applied at both the canal and the farm systems. That decline of the water table favours salinity control and reduces capillary rise, thus reducing the groundwater evaporation and uptake by plant roots; that reduction may attain 128Â mm. However, predictions may change depending on the way how water-saving measures are applied, which may be different of assumptions made; therefore, there is the need to perform a follow-up of the interventions in order to update predictions. Results indicate the need for appropriate research leading to improved irrigation management when the decline of the groundwater level will reduce groundwater contribution to vegetation growth.

2008 - Ecological Engineering
The influence of dams on ecohydrological conditions in the Huaihe River basin, China

Maintaining natural hydrologic variability is essential in conserving native riverine biota and river ecosystem integrity. Hydrologic regimes play a major role in structuring the biotic diversity within river ecosystems, as they control key habitat conditions within the river channel, the floodplain, etc. Alterations in strearnflow regimes may modify many of these habitat attributes and impair ecosystem connectivity. There are many dams constructed in the Huaihe River basin that are drastically altering the natural hydrologic regimes of the river. We selected the Bengbu Sluice as a control node to study the influence of the Bengbu Sluice and all its upstream dams on the hydrologic regime. Using Indicators of Hydrologic Alteration and Range ofVariability Approach methods, we assessed hydrologic alteration at the strearngauge site to demonstrate the influence of dams on ecohydrological conditions in the Huaihe Riverbasin. The results show that dams have a stronginfluence on ecohydrologiCal conditions, especially in dry seasons. The river ecohydrological targets and the minimum ecological and environmental flow requirements for the Benglou section defined by this study can support ecosystem management and restoration plans and provide ecological operations for the Bengbu Sluice. @ 2008 Elsevier B.V All rights reserved.

2009 - Journal of Earth System Science
SCS-CN and GIS-based approach for identifying potential water harvesting sites in the Kali Watershed, Mahi River Basin, India

The Kali sub-watershed is situated in the semi-arid region of Gujarat, India and forms a part of the Mahi River Watershed. This watershed receives an average annual rainfall of 900mm mainly between July and September. Due to high runoff potential, evapo-transpiration and poor infiltration, drought like situation prevails in this area from December to June almost every year. In this paper, augmentation of water resource is proposed by construction of runoff harvesting structures like check dam, percolation pond, farm pond, well and subsurface dyke. The site suitability for different water harvesting structures is determined by considering spatially varying parameters like runoff potential, slope, fracture pattern and micro-watershed area. GIS is utilised as a tool to store, analyse and integrate spatial and attribute information pertaining to runoff, slope, drainage and fracture. The runoff derived by SCS-CN method is a function of runoff potential which can be expressed in terms of runoff coefficient (ratio between the runoff and rainfall) which can be classified into three classes, viz., high (>40%), moderate (20–40%) and low (<20%). In addition to IMSD, FAO specifications for water harvesting/recharging structures, parameters such as effective storage, rock mass permeability are herein considered to augment effective storage. Using the overlay and decision tree concepts in GIS, potential water harvesting sites are identified. The derived sites are field investigated for suitability and implementation. In all, the accuracy of the site selection at implementation level varies from 80–100%.

2009 - Geophysical Research Letters
Role of rivers in the seasonal variations of terrestrial water storage over global basins

[1] The role of rivers in total terrestrial water storage (TWS) variations is evaluated in 29 basins. The contribution of individual storage components to total TWS is investigated by using ensemble hydrological simulations with river routing. The observed Gravity Recovery And Climate Experiment (GRACE) TWS data are used to validate model simulations. It is found TWS simulations are more accurate when river storage is taken into account except for dry basins. Rivers play different roles in various climatic regions as indicated by two new indices quantifying the significance of each TWS component and their interactions. River storage, which effectively includes downslope movement of shallow groundwater, explains up to 73% of TWS variations in Amazon. It also acts as “buffer” which smoothes TWS seasonal variations particularly in snow-dominated basins. Neglecting river storage may lead to mismatch in the amplitude and phase of TWS seasonal variations compared to the GRACE observations.

2010 - Ecological applications : a publication of the Ecological Society of America
Least-cost control of agricultural nutrient contributions to the Gulf of Mexico hypoxic zone.

In 2008, the hypoxic zone in the Gulf of Mexico, measuring 20 720 km2, was one of the two largest reported since measurement of the zone began in 1985. The extent of the hypoxic zone is related to nitrogen and phosphorous loadings originating on agricultural fields in the upper Midwest. This study combines the tools of evolutionary computation with a water quality model and cost data to develop a trade-off frontier for the Upper Mississippi River Basin specifying the least cost of achieving nutrient reductions and the location of the agricultural conservation practices needed. The frontier allows policymakers and stakeholders to explicitly see the trade-offs between cost and nutrient reductions. For example, the cost of reducing annual nitrate-N loadings by 30% is estimated to be US$1.4 billion/year, with a concomitant 36% reduction in P and the cost of reducing annual P loadings by 30% is estimated to be US$370 million/year, with a concomitant 9% reduction in nitrate-N.

1999 - Journal of Geophysical Research
Hydrologic effects of frozen soils in the upper Mississippi River basin

The variable infiltration capacity (VIC) macroscale hydrologic model was modified to improve its performance in cold regions by adding frozen soil and energy balance snow accumulation and ablation algorithms. Frozen soil penetration was determined by solving thermal fluxes through the soil column. Infiltration and runoff response parameterizations were modified to reflect the simulated ice content of the soil. The revised model was tested using point data from the University of Minnesota Rosemount Agricultural Experiment Station and subsequently applied to two subcatchments in the upper Mississippi River basin. The point tests showed that the model was able to reproduce observations of the snowpack, soil liquid water content, and freezing and thawing front depths. Comparisons of simulated discharge from the two subbasins showed that the frozen soil algorithm reduced infiltration during winter and spring thaws and increased rapid runoff response. However, the magnitude of the increased runoff response is relatively modest, at the scale of the two upper Mississippi subbasins tested.

1962
Direct Absorption of Solar Radiation by Atmospheric Water Vapor, Carbon Dioxide and Molecular Oxygen.

Abstract Based mainly on Howard, Burch and Williams' laboratory absorption data for the near infrared H2O and CO2, bands, and on the solar absorption data for the red and near infrared O2 bands, the direct absorption of solar radiation in near infrared atmospheric bands has been estimated. The estimated absorptivities of the H2O bands in the interval from 0.7 to 2.1 μ are in fair agreement with MeDonald's estimates which are based on Fowle's absorption data. However the absorptivities of the H2O bands from 0.7 to 6.3 μ are larger than McDonald's values. CO2 and O2 absorptions become increasingly important in the upper troposphere and in the stratosphere. Average heating (deg C day−1) was also estimated for London's model atmospheres for clear sky conditions, and compared with the similar estimate made by Roach. For the atmosphere above 300 mb the heating estimated in this paper exceeds that estimated by Roach. Conceivable causes of this discrepancy are pointed out.

Inferring changes in terrestrial water storage using ERA-40 reanalysis data: The Mississippi River Basin

Sonia I. Seneviratne
|
Christoph Schär
|
Pedro Viterbo
|
S. Seneviratne
|
D. Lüthi
|
C. Schär
|
P. Viterbo
|
Daniel Lüthi

Abstract:Terrestrial water storage is an essential part of the hydrological cycle, encompassing crucial elements of the climate system, such as soil moisture, groundwater, snow, and land ice. On a regional scale, it is however not a readily measured variable and observations of its individual components are scarce. This study investigates the feasability of estimating monthly terrestrial water-storage variations from water-balance computations, using the following three variables: water vapor flux convergence, atmospheric water vapor content, and river runoff. The two first variables are available with high resolution and good accuracy in the present reanalysis datasets, and river runoff is commonly measured in most parts of the world. The applicability of this approach is tested in a 10-yr (1987–96) case study for the Mississippi River basin. Data used include European Centre for Medium- Range Weather Forecasts 40-yr reanalysis (ERA-40) data (water vapor flux and atmospheric water vapor content) and runo...

参考文献

[1]  S. Manabe,et al.  Detectability of Summer Dryness Caused by Greenhouse Warming , 1999 .

[2]  Paul A. Dirmeyer,et al.  Contrasting evaporative moisture sources during the drought of 1988 and the flood of 1993 , 1999 .

[3]  D. Lüthi,et al.  The Soil-Precipitation Feedback: A Process Study with a Regional Climate Model , 1999 .

[4]  Randal D. Koster,et al.  The Interplay between Transpiration and Runoff Formulations in Land Surface Schemes Used with Atmospheric Models , 1997 .

[5]  D. Lüthi,et al.  Climate impacts of European‐scale anthropogenic vegetation changes: A sensitivity study using a regional climate model , 2001 .

[6]  E. Rasmusson,et al.  Atmospheric Water Vapor Transport and the Water Balance of North America , 1968 .

[7]  J. Pal,et al.  Summer dryness in a warmer climate: a process study with a regional climate model , 2002 .

[8]  Adrian Simmons,et al.  Use of Reduced Gaussian Grids in Spectral Models , 1991 .

[9]  A. Betts,et al.  Surface Energy and Water Balance for the Arkansas-Red River Basin from the ECMWF Reanalysis , 1998 .

[10]  Pedro Viterbo,et al.  Impact of the ECMWF reanalysis soil water on forecasts of the July 1993 Mississippi flood , 1999 .

[11]  Miller,et al.  The Anomalous Rainfall over the United States during July 1993: Sensitivity to Land Surface Parameterization and Soil Moisture Anomalies , 1996 .

[12]  F. Bryan,et al.  Time variability of the Earth's gravity field: Hydrological and oceanic effects and their possible detection using GRACE , 1998 .

[13]  P. Dirmeyer,et al.  A 36-yr Climatological Description of the Evaporative Sources of Warm-Season Precipitation in the Mississippi River Basin , 2001 .

[14]  Ecmwf Newsletter,et al.  EUROPEAN CENTRE FOR MEDIUM-RANGE WEATHER FORECASTS , 2004 .

[15]  R. Avissar,et al.  The Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP): An overview , 1996 .

[16]  Jean-François Mahfouf,et al.  Evaluation of the Optimum Interpolation and Nudging Techniques for Soil Moisture Analysis Using FIFE Data , 2000 .

[17]  J. Shukla,et al.  Influence of Land-Surface Evapotranspiration on the Earth's Climate , 1982, Science.

[18]  Elfatih A. B. Eltahir,et al.  An analysis of the soil moisture‐rainfall feedback, based on direct observations from Illinois , 1997 .

[19]  C. Schär,et al.  The role of soil states in medium-range weather predictability , 2001 .

[20]  John W. Pomeroy,et al.  Snowcover Accumulation, Relocation, and Management , 1995 .

[21]  J. Roads,et al.  Large-Scale Aspects of the United States Hydrologic Cycle , 1994 .

[22]  P. Courtier,et al.  The ECMWF implementation of three‐dimensional variational assimilation (3D‐Var). I: Formulation , 1998 .

[23]  G. Salvucci.  Soil and moisture independent estimation of stage‐two evaporation from potential evaporation and albedo or surface temperature , 1997 .

[24]  Jean-Christophe Calvet,et al.  From Near-Surface to Root-Zone Soil Moisture Using Year-Round Data , 2000 .

[25]  A. J. Dolman,et al.  The Pilot Phase of the Global Soil Wetness Project , 1999 .

[26]  Ming-Jen Yang,et al.  The Coastal Observation and Simulation with Topography (COAST) Experiment , 1997 .

[27]  Thomas J. Jackson,et al.  Soil moisture mapping at regional scales using microwave radiometry: the Southern Great Plains Hydrology Experiment , 1999, IEEE Trans. Geosci. Remote. Sens..

[28]  Pedro Viterbo,et al.  The land surface‐atmosphere interaction: A review based on observational and global modeling perspectives , 1996 .

[29]  V. Starr,et al.  On the Global Balance of Water Vapor and the Hydrology of Deserts , 1958 .

[30]  Matthew Rodell,et al.  An analysis of terrestrial water storage variations in Illinois with implications for the Gravity Recovery and Climate Experiment (GRACE) , 2001 .

[31]  Michael G. Bosilovich,et al.  Intercomparison of water and energy budgets for five Mississippi subbasins between ECMWF reanalysis (ERA‐40) and NASA Data Assimilation Office fvGCM for 1990–1999 , 2003 .

[32]  H. Matsuyama,et al.  Estimates of continental-scale soil wetness and comparison with the soil moisture data of Mintz and Serafini , 1997 .

[33]  P. Courtier,et al.  The ECMWF implementation of three‐dimensional variational assimilation (3D‐Var). II: Structure functions , 1998 .

[34]  S. Schubert,et al.  Precipitation Recycling over the Central United States Diagnosed from the GEOS-1 Data Assimilation System , 2001 .

[35]  T. Oki,et al.  Seasonal cycle of water storage in major river basins of the world , 2001 .

[36]  C. Ropelewski,et al.  The Observed Mean Annual Cycle of Moisture Budgets over the Central United States (1973-92) , 1998 .

[37]  A. K. Betts,et al.  O ine validation of the ERA 40 surface scheme , 2000 .

[38]  Albert Rango,et al.  Spaceborne remote sensing for snow hydrology applications , 1996 .

[39]  R. Koster,et al.  Variance and Predictability of Precipitation at Seasonal-to-Interannual Timescales , 2000 .

[40]  M. Estoque,et al.  WATER-VAPOR TRANSFER OVER THE NORTH AMERICAN CONTINENT , 1954 .

[41]  Hugo A. Loáiciga,et al.  Groundwater fluxes in the global hydrologic cycle: past, present and future , 1993 .

[42]  J. Peixoto,et al.  Physics of climate , 1992 .

[43]  Scott A. Isard,et al.  A Soil Moisture Climatology of Illinois , 1994 .

[44]  A. Robock,et al.  The Global Soil Moisture Data Bank , 2000 .

[45]  Douglas A. Miller,et al.  GCIP water and energy budget synthesis (WEBS) , 2002 .

[46]  E. Rasmusson,et al.  Studies of North American continental‐scale hydrology using Eta model forecast products , 1996 .

[47]  Taikan Oki,et al.  Global atmospheric water balance and runoff from large river basins , 1995 .

[48]  Kevin E. Trenberth,et al.  Estimates of Freshwater Discharge from Continents: Latitudinal and Seasonal Variations , 2002 .

[49]  Suxia Liu,et al.  Evaluation of Global Soil Wetness Project Soil Moisture Simulations , 1999 .

[50]  Robert A. Berner,et al.  The Global Water Cycle , 1987 .

[51]  C. Ropelewski,et al.  Biases of the observed atmospheric water budgets over the central United States , 1999 .

[52]  K. Trenberth.  Truncation and use of model-coordinate data , 1995 .

[53]  A. Betts,et al.  Basin‐scale surface water and energy budgets for the Mississippi from the ECMWF reanalysis , 1999 .

[54]  S. Changnon,et al.  Relations between precipitation and shallow groundwater in Illinois , 1988 .

[55]  P. Domenico,et al.  Physical and chemical hydrogeology , 1990 .

[56]  P. Milly,et al.  Sensitivity of the Global Water Cycle to the Water-Holding Capacity of Land , 1994 .

[57]  Kevin E. Trenberth,et al.  Evaluation of the Global Atmospheric Moisture Budget as Seen from Analyses , 1995 .

[58]  K. Trenberth.  Using Atmospheric Budgets as a Constraint on Surface Fluxes , 1997 .

[59]  E. Rasmusson,et al.  Mississippi Moisture Budgets on Regional Scales , 1999 .

[60]  K. Trenberth,et al.  Conservation of Mass in Three Dimensions in Global Analyses , 1995 .

[61]  Jeffrey B. Basara,et al.  Improved Installation Procedures for Deep-Layer Soil Moisture Measurements , 2000 .

[62]  W. Gutowski,et al.  Atmospheric Water Vapor Transport in NCEP–NCAR Reanalyses: Comparison with River Discharge in the Central United States , 1997 .

[63]  S. Seneviratne.  Terrestrial water storage , 2003 .

[64]  Mikko Alestalo.  The Atmospheric Water Vapour Budget Over Europe , 1983 .

[65]  E. Rasmusson.  A STUDY OF THE HYDROLOGY OF EASTERN NORTH AMERICA USING ATMOSPHERIC VAPOR FLUX DATA , 1971 .

[66]  J. Skopp,et al.  Physical and Chemical Hydrogeology, 2nd edition , 1999 .

[67]  Elfatih A. B. Eltahir,et al.  Hydroclimatology of Illinois: A comparison of monthly evaporation estimates based on atmospheric water balance and soil water balance , 1998 .

引用
Evaluation of surface water fluxes of the pan‐Arctic land region with a land surface model and ERA‐40 reanalysis
2006
Swiss prealpine Rietholzbach research catchment and lysimeter: 32 year time series and 2003 drought event
2012
Impact of the Sudd wetland on the Nile hydroclimatology
2005
Basin‐scale water‐balance estimates of terrestrial water storage variations from ECMWF operational forecast analysis
2006
Catchments as simple dynamical systems: Experience from a Swiss prealpine catchment
2010
Long‐term groundwater storage trends estimated from streamflow records: Climatic perspective
2008
A global analysis of temporal and spatial variations in continental water storage
2007
Can InSAR Coherence and Closure Phase Be Used to Estimate Soil Moisture Changes?
Remote. Sens.
2020
Comparison of GRACE with in situ hydrological measurement data shows storage depletion in Hai River basin, Northern China
2009
Intercomparison of Water and Energy Budgets for Five Mississippi Sub-basins between ECMWF Reanalysis (ERA-40) and NASA-DAO fvGCM for 1990-1999
2002
Improved Remotely Sensed Total Basin Discharge and Its Seasonal Error Characterization in the Yangtze River Basin
Sensors
2019
A comparison of terrestrial water storage variations from GRACE with in situ measurements from Illinois
2006
New data sets to estimate terrestrial water storage change
2007
Assessment of Gravity Recovery and Climate Experiment (GRACE) temporal signature over the upper Zambezi
2006
The role of horizontal resolution in simulating drivers of the global hydrological cycle
Climate Dynamics
2014
Absolute versus temporal anomaly and percent of saturation soil moisture spatial variability for six networks worldwide
2014
New diagnostic estimates of variations in terrestrial water storage based on ERA‐Interim data
2011
Annual and interannual variations in terrestrial water storage during and following a period of drought in South Carolina, USA
2011
Use of a soil moisture network for drought monitoring in the Czech Republic
Theoretical and Applied Climatology
2011
The ERA-40 Reanalysis
2004