Modelling socio-hydrological systems: a review of concepts, approaches and applications
Summary: This paper reviews literature surrounding many aspects of socio-hydrological modelling; this includes a background to the subject of socio-hydrology, reasons for modelling, potential applications and concepts that underpin models, as well as describing several modelling techniques and how they may be applied in socio-hydrology.
Hydrol. Earth Syst. Sci. Discuss., 12, 8761-8851, doi:10.5194/hessd-12-8761-2015, 2015
Reviving the Ganges Water Machine: why?
Summary: The Ganges River Basin has abundant surface water and groundwater resources, but the seasonal monsoon causes a mismatch between supply and demand as well as flooding. Addressing this mismatch requires substantial additional storage. Reviving the Ganges Water Machine, long known as use of subsurface storage with accelerated surface-subsurface water exchange, to meet the unmet water demand, ranging from 59 to 119 billion m3, is the most opportune solution to the pending water crises in the Basin.
Hydrol. Earth Syst. Sci. Discuss., 12, 8727-8759, doi:10.5194/hessd-12-8727-2015, 2015
A parsimonious analytical model for simulating multispecies plume migration
Summary: A parsimonious analytical model for predicting the plume behavior of decaying contaminant is presented in this study. The analytical results indicate that the parsimonious analytical solutions are robust and accurate. The solutions are useful for serving as simulation or screening tools for assessing plume behaviors of decaying contaminants including the radionuclides and dissolved chlorinated solvents in groundwater systems.
Hydrol. Earth Syst. Sci. Discuss., 12, 8675-8726, doi:10.5194/hessd-12-8675-2015, 2015
Recent climatic, cryospheric, and hydrological changes over the interior of western Canada: a synthesis and review
Summary: This paper provides an integrated review and up-to-date synthesis of the observed changes in air temperature, precipitation, seasonal snow cover, mountain glaciers, permafrost, freshwater ice cover, and river discharge over the interior of western Canada since the mid or late-20th century. Important long-term observational networks and datasets are described, and qualitative linkages among the changing Earth system components are highlighted.
Hydrol. Earth Syst. Sci. Discuss., 12, 8615-8674, doi:10.5194/hessd-12-8615-2015, 2015
Nitrate sinks and sources as controls of spatio-temporal water quality dynamics in an agricultural headwater catchment
Summary: We quantify the spatio-temporal impact of distinct nitrate sinks and sources on stream network nitrate dynamics in an agricultural headwater. By applying a data-driven modelling approach we are able to fully distinguish between mixing and dilution processes and biogeochemical in-stream removal processes along the stream network. In-stream nitrate removal is estimated by applying a novel transfer coefficient based on energy availability.
Hydrol. Earth Syst. Sci. Discuss., 12, 8577-8614, doi:10.5194/hessd-12-8577-2015, 2015
Examination for robustness of parametric estimators for flood statistics in the context of extraordinary extreme events
Summary: In the last few years to occurence of extraordinary extreme flood events rised the question for a suitable statistical model to describe this flood behaviour and give a possibility for the calculation of high quantiles. Since the occurence of these extreme events in very short time series (less than 100 years) could influence the statistical estimators leading to a too high estimation we want to use robust estimators to give a moderate weighting to these floods. The results are given here.
Hydrol. Earth Syst. Sci. Discuss., 12, 8553-8576, doi:10.5194/hessd-12-8553-2015, 2015
Evaluation of soil moisture downscaling using a simple thermal based proxy – the REMEDHUS network (Spain) example
Summary: 1. Comprehensive evaluation of a simple newly developed downscaling scheme using in-situ measurements from REMEDHUS network. 2. First time to cross compare the performance of the downscaled soil moisture from MODIS and MSG SEVIRI. 3. Evaluate the performance of the downscaled soil moisture at different spatial resolutions. 4.Explore the influence of LST, vegetation index, terrain, clouds, and land cover heterogeneity on the performance of VTCI.
Hydrol. Earth Syst. Sci. Discuss., 12, 8505-8551, doi:10.5194/hessd-12-8505-2015, 2015
Mediterranean irrigation under climate change: more efficient irrigation needed to compensate increases in irrigation water requirements
Summary: At present the Mediterranean region could save 35 % of water by implementing more efficient irrigation and conveyance systems (EICS). By 2080-2090 the region might face an increase in gross irrigation requirements (IR) up to 74 % due to climate change and population growth. EICS may be able to compensate to some degree these increases. Most countries from the Northern and Eastern Mediterranean have a high risk of not being able to meet future IR due to water scarcity.
Hydrol. Earth Syst. Sci. Discuss., 12, 8459-8504, doi:10.5194/hessd-12-8459-2015, 2015
The Normalized Difference Infrared Index (NDII) as a proxy for soil moisture storage in hydrological modelling
Summary: We demonstrated that the readily available NDII Remote Sensing product is a very useful and accurate proxi for moisture storage in the root zone of vegetation. We compared the temporal variation of the NDII with the root zone storage in a hydrological model of 8 catchments in the Upper Ping river in Thailand, yielding very good results. Having a reliable NDII product that can help us to estimate the actual moisture storage in catchments is a major contribution to prediction in ungauged basins.
Hydrol. Earth Syst. Sci. Discuss., 12, 8419-8457, doi:10.5194/hessd-12-8419-2015, 2015
Analytical approach for determining the mean water level profile in an estuary with substantial fresh water discharge
Summary: In this paper, an analytical model for tide-river dynamics has been used to understand the influence of tide and fresh water discharge on the rise of mean water level along the estuary, which remains poorly understood. It is shown that the mean water level is influenced primarily by the tide-river interaction in the tide-dominated region, while it is mainly controlled by the river flow in the upstream part of the estuary.
Hydrol. Earth Syst. Sci. Discuss., 12, 8381-8417, doi:10.5194/hessd-12-8381-2015, 2015
High-frequency monitoring reveals nutrient sources and transport processes in an agriculture-dominated lowland water system
Hydrol. Earth Syst. Sci. Discuss., 12, 8337-8380, doi:10.5194/hessd-12-8337-2015, 2015
A question driven socio-hydrological modeling process
Summary: The paper, entitled "A Question Driven Socio-hydrological Modeling Process", presents a new process for developing conceptual models of coupled socio-hydrological systems. This modeling process is demonstrated by developing a model of a hypothetical system based on a hypothesis linking per capita water demand changes to supply reliability. The resulting model illustrates both the modeling process and the relevance of the hypothesis for reservoir operations policy.
Hydrol. Earth Syst. Sci. Discuss., 12, 8289-8335, doi:10.5194/hessd-12-8289-2015, 2015
A century scale human-induced hydrological and ecological changes of wetlands of two large river basins in Australia (Murray) and China (Yangtze): development of an adaptive water resource management framework
Hydrol. Earth Syst. Sci. Discuss., 12, 8247-8287, doi:10.5194/hessd-12-8247-2015, 2015
The use of semi-structured interviews for the characterisation of farmer irrigation practices
Summary: Semi-structured interviews provide an effective and efficient way of collecting qualitative and quantitative data on water use practices. Interviews are organised around a topic guide, which help lead the conversation while allowing sufficient opportunity to identify issues previously unknown to the researcher. The use of semi-structured interviews could significantly and quickly improve insight on water resources, leading to more realistic future management options and increased water security.
Hydrol. Earth Syst. Sci. Discuss., 12, 8221-8246, doi:10.5194/hessd-12-8221-2015, 2015
On the propagation of diel signals in river networks using analytic solutions of flow equations
Summary: We design and implement a theoretical experiment to show that, under low flow conditions, observed streamflow discrepancies between early and late summer can be attributed to different flow velocities in the river network. By developing an analytic solution to represent flow along a given river network, we emphasize the dependence of streamflow amplitude and time delay on the geomorphology of the network. We also simulate using a realistic river network to highlight the effects of scale.
Hydrol. Earth Syst. Sci. Discuss., 12, 8175-8220, doi:10.5194/hessd-12-8175-2015, 2015
Data assimilation in integrated hydrological modelling in the presence of observation bias
Hydrol. Earth Syst. Sci. Discuss., 12, 8131-8173, doi:10.5194/hessd-12-8131-2015, 2015
Assessing various drought indicators in representing drought in boreal forests in Finland
Hydrol. Earth Syst. Sci. Discuss., 12, 8091-8129, doi:10.5194/hessd-12-8091-2015, 2015
Time-series of tritium, stable isotopes and chloride reveal short-term variations in groundwater contribution to a stream
Summary: The transit time of water is a key indicator of hydrological processes at the catchment scale. Our results suggest that the use of tritium time-series in streamwater can be highly valuable for assessing the temporal variations in the transit time of older groundwater contributions to streamflow. We also show that shortly after high flow events, the transit time of the old water fraction increases and tends to approach the groundwater residence time.
Hydrol. Earth Syst. Sci. Discuss., 12, 8035-8089, doi:10.5194/hessd-12-8035-2015, 2015
A rainfall design method for spatial flood risk assessment: considering multiple flood sources
Summary: In this paper, a rainfall design method for spatial flood risk assessment, which considers the joint effects of multiple flood sources, is proposed. The concept of critical rainfall duration determined by the concentration time of flooding is introduced to connect response characteristics of different flood sources with rainfall. A copula method is then adopted to capture the correlation of rainfall amount with different critical rainfall duration.
Hydrol. Earth Syst. Sci. Discuss., 12, 8005-8033, doi:10.5194/hessd-12-8005-2015, 2015
The impact of near-surface soil moisture assimilation at subseasonal, seasonal, and inter-annual time scales
Summary: A soil moisture assimilation experiment is evaluated separately at sub-seasonal, seasonal, and inter-annual time scales. In addition to previously reported improvements in sub-seasonal scale soil moisture, it is show that such an assimilation can also improve the model soil moisture at seasonal and inter-annual time scales, demonstrating the potential for near-surface soil moisture assimilation to improve model representation of important long term events, such as droughts.
Hydrol. Earth Syst. Sci. Discuss., 12, 7971-8004, doi:10.5194/hessd-12-7971-2015, 2015
Influence of climate variability on water partitioning and effective energy and mass transfer (EEMT) in a semi-arid critical zone
Hydrol. Earth Syst. Sci. Discuss., 12, 7933-7969, doi:10.5194/hessd-12-7933-2015, 2015
Soil storage influences climate–evapotranspiration interactions in three western United States catchments
Hydrol. Earth Syst. Sci. Discuss., 12, 7893-7931, doi:10.5194/hessd-12-7893-2015, 2015
Technical Note: Testing an improved index for analysing storm nutrient hysteresis
Summary: This paper examines the current methodologies for quantifying storm behaviour through hysteresis analysis, and explores a new method. Each method is systematically tested and the impact on the results is examined. Recommendations are made regarding the most effective method of calculating a hysteresis index. This new method allows storm hysteresis behaviour to be directly compared between storms, parameters and catchments, meaning it has wide application potential in water quality research.
Hydrol. Earth Syst. Sci. Discuss., 12, 7875-7892, doi:10.5194/hessd-12-7875-2015, 2015
Crop-specific seasonal estimates of irrigation water demand in South Asia
Summary: This study presents crop specific seasonal estimates of irrigation water demand in South Asia resulting from the typical practice of multiple cropping. We show that crop irrigation water demand differs sharply between seasons and regions; in Pakistan, winter and summer irrigation demands are almost equal, whereas in Bangladesh the demand in winter is much higher. Insight in where and when sufficient irrigation water supply is critical to sustain food production, is essential to plan adaptation.
Hydrol. Earth Syst. Sci. Discuss., 12, 7843-7873, doi:10.5194/hessd-12-7843-2015, 2015
Does the Budyko curve reflect a maximum power state of hydrological systems? A backward analysis
Summary: We derived mathematical formulations of relations between relative wetness and gradients driving runoff and evaporation for a one-box model such that when conductances are optimized with the maximum power principle, the model leads exactly to a point on the Budyko curve. By adding dry spells and dynamics in actual evaporation, the model compared well with catchment observations without calibrating any parameter. The maximum power principle may thus be used to derive the Budyko curve.
Hydrol. Earth Syst. Sci. Discuss., 12, 7821-7842, doi:10.5194/hessd-12-7821-2015, 2015
Impacts of land use change and climate variations on annual inflow into Miyun Reservoir, Beijing, China
Hydrol. Earth Syst. Sci. Discuss., 12, 7785-7819, doi:10.5194/hessd-12-7785-2015, 2015
Uncertainties in calculating precipitation climatology in East Asia
Summary: This study examined the uncertainty in climatological precipitation in East Asia, calculated from five gridded analysis datasets based on in-situ rain gauge observations from 1980 to 2007. It is found that the regions of large uncertainties are typically lightly populated and are characterized by severe terrain and/or extreme high elevations. Thus, care must be taken in using long-term trends calculated from gridded precipitation analysis data for climate studies over such regions in East Asia.
Hydrol. Earth Syst. Sci. Discuss., 12, 7765-7783, doi:10.5194/hessd-12-7765-2015, 2015
Nonlinear effects of locally heterogeneous hydraulic conductivity fields on regional stream–aquifer exchanges
Summary: Computation experiments found the effects of small-scale heterogeneities do influence estimates of aquifer-stream exchanges. The effects are nonlinear in the sense that simulated discharges from aquifers to streams are systematically lower than discharges produced by a base model parameterized with coarse effective K. Although aquifer heterogeneities are uncorrelated at local scales, they appear to induce coherent slow-paths in groundwater fluxes that in turn reduce aquifer-stream exchanges.
Hydrol. Earth Syst. Sci. Discuss., 12, 7727-7764, doi:10.5194/hessd-12-7727-2015, 2015
Does drought alter hydrological functions in forest soils? An infiltration experiment
Summary: It is usually assumed that soil properties are not affected by drought events. We used dye tracer experiments to test this assumption on six forest soils, which were forced into drought conditions. The results of this study show clear evidence for changes in infiltration pathways. In addition, most soils developed soil water repellency. Overall, the results suggest that the past climatic conditions are more important than the actual soil moisture status regarding hydrophobicity and infiltration.
Hydrol. Earth Syst. Sci. Discuss., 12, 7689-7725, doi:10.5194/hessd-12-7689-2015, 2015
Near–surface air temperature and snow skin temperature comparison from CREST-SAFE station data with MODIS land surface temperature data
Hydrol. Earth Syst. Sci. Discuss., 12, 7665-7687, doi:10.5194/hessd-12-7665-2015, 2015
Morphological dynamics of an englacial channel
Summary: Ten years of direct observations of an englacial conduit in a cold based glacier in Svalbard, document for the first time how a vertical meltwater waterfall (moulin) is formed from gradual incision of a meltwater channel. This evolution appears to be dominated by nickpoints that incise upstream at rates several times faster than the vertical incision in adjacent near horisontal channel sections.
Hydrol. Earth Syst. Sci. Discuss., 12, 7615-7664, doi:10.5194/hessd-12-7615-2015, 2015
Effects of cultivation and reforestation on suspended sediment concentrations: a case study in a mountainous catchment in China
Summary: Whether changes in land use/cover alter soil loss by changing the runoff volume or by changing the suspended sediment concentration (SSC) has received little attention. This paper presents suspended sediment concentration dynamics and the relationship between SSC and discharge (Q) in the 8973-km2 Du catchment and its sub-catchment (4635 km2). ANOVA indicated that the SSC did not significantly change under cultivation for low and moderate flows, but was significantly different under high flow.
Hydrol. Earth Syst. Sci. Discuss., 12, 7583-7614, doi:10.5194/hessd-12-7583-2015, 2015
Diagnosing hydrological limitations of a Land Surface Model: application of JULES to a deep-groundwater chalk basin
Summary: o A strategy to diagnose hydrological limitations of a Land Surface Model o Land Surface Model adaptation for hydrological applications o Highlights challenges faced while moving towards high resolution modeling
Hydrol. Earth Syst. Sci. Discuss., 12, 7541-7582, doi:10.5194/hessd-12-7541-2015, 2015
Analysis of three-dimensional groundwater flow toward a radial collector well in a finite-extent unconfined aquifer
Summary: Existing solutions for the problem of pumping at a radial collector well (RCW) in unconfined aquifers either require laborious calculation or predict divergent results at a middle period of pumping. This study relaxes above two limitations to develop a new analytical solution for the problem. The application of the solution is convenient for those who are not familiar with numerical methods.
Hydrol. Earth Syst. Sci. Discuss., 12, 7503-7540, doi:10.5194/hessd-12-7503-2015, 2015
Estimating evapotranspiration with thermal UAV data and two source energy balance models
Summary: 1) Thermal images collected with an Unmanned Aerial Vehicle (UAV) are applied to two-source energy balance models in order to estimate evapotranspiration in very high resolution. 2) Thermal images are successfully mosaicked and processed into model input. 3) The two-source energy balance models (TSEB-PT and DTD) are validated during overcast weather conditions. 4) The DTD model provide results in best agreement with Eddy covariance data.
Hydrol. Earth Syst. Sci. Discuss., 12, 7469-7502, doi:10.5194/hessd-12-7469-2015, 2015
Sub-daily runoff simulations with parameters inferred at the daily time scale
Summary: In this study it was found that time-scale dependencies of hydrological model parameters are a result of the numerical method used in the model rather than a real time-scale-data dependence. This study further indicates that as soon as sub-daily driving data can be secured, flood forecasting in watersheds with sub-daily concentration times is possible with model parameter values inferred from long time series of daily data, as long as an appropriate numerical method is used.
Hydrol. Earth Syst. Sci. Discuss., 12, 7437-7467, doi:10.5194/hessd-12-7437-2015, 2015
Multiscale evaluation of the standardized precipitation index as a groundwater drought indicator
Summary: In a maiden attempt, we performed a multiscale evaluation of the widely-used SPI to characterize local and regional scale groundwater (GW) droughts using observations at 2040 groundwater wells in Germany and the Netherlands. From this data-based exploratory analysis, we provide sufficient evidences regarding the inability of the SPI to characterize GW drought events, and stress the need for more GW observations and accounting for regional hydrogeological characteristics in GW drought monitoring.
Hydrol. Earth Syst. Sci. Discuss., 12, 7405-7436, doi:10.5194/hessd-12-7405-2015, 2015
Comparing the Ensemble and Extended Kalman Filters for in situ soil moisture assimilation with contrasting soil conditions
Summary: The Ensemble Kalman Filter (EnKF) and Simplified Extended Kalman Filter (SEKF) root-zone soil moisture analyses are compared when assimilating in situ surface observations. Both methods perform similarly and improve on the model, despite poor linear assumptions with certain soil conditions. Unlike the SEKF, the EnKF flow-dependent background-error covariance captures the seasonal variability in the soil moisture errors and has the potential to exploit a stochastic rainfall error model.
Hydrol. Earth Syst. Sci. Discuss., 12, 7353-7403, doi:10.5194/hessd-12-7353-2015, 2015
Future changes in flash flood frequency and intensity of the Tha Di River (Thailand) based on rainfall–runoff modeling and advanced delta change scaling
Summary: HBV-Light was calibrated and validated with simultaneously recorded discharge and precipitation data of the years 1989–2009. Results show, that the raw Regional Climate Model series overestimate precipitation sums by the factor of two or more. HBV modeling shows an increase for the yearly average cumulative precipitation until the end of the century between 10-30%. The dry season is likely to become longer and drier.
Hydrol. Earth Syst. Sci. Discuss., 12, 7327-7352, doi:10.5194/hessd-12-7327-2015, 2015
High-end climate change impact on European water availability and stress: exploring the presence of biases
Summary: A set of the new Euro-CORDEX projections is used to examine the impact of high-end scenarios on water availability and stress at pan-European scale. Drought climatology is investigated for five major European basins along with the impact of +2C versus +4C warming. The effect of bias correction is also examined. The selection of the observational dataset used for bias adjustment has an impact on the projected signal that could be of the same order of magnitude as the selection of the RCM.
Hydrol. Earth Syst. Sci. Discuss., 12, 7267-7325, doi:10.5194/hessd-12-7267-2015, 2015
Rainfall erosivity in subtropical catchments and implications for erosion and particle-bound contaminant transfer: a case-study of the Fukushima region
Summary: Characterizing rainfall erosivity in the Fukushima fallout-impacted region is important for predicting radiocesium behaviour. The majority of rainfall (60 %) and rainfall erosivity (86 %) occurs between June and October. Understanding the impact of typhoons will be important for managing sediment and sediment-bound contaminant transfers in the Fukushima region and other subtropical regions impacted by cyclonic activity.
Hydrol. Earth Syst. Sci. Discuss., 12, 7225-7266, doi:10.5194/hessd-12-7225-2015, 2015
Accounting for three sources of uncertainty in ensemble hydrological forecasting
Hydrol. Earth Syst. Sci. Discuss., 12, 7179-7223, doi:10.5194/hessd-12-7179-2015, 2015
The SPARSE model for the prediction of water stress and evapotranspiration components from thermal infra-red data and its evaluation over irrigated and rainfed wheat
Summary: The paper presents a new model (SPARSE) to estimate total evapotranspiration as well as its components (evaporation and transpiration) from remote sensing data in the thermal infra-red domain. The limits of computing two unknowns (evaporation and transpiration) out of one piece of information (one surface temperature) is assessed theoretically. The model performance in retrieving the components as well as the water stress, is assessed for two wheat crops (one irrigated and one rainfed).
Hydrol. Earth Syst. Sci. Discuss., 12, 7127-7178, doi:10.5194/hessd-12-7127-2015, 2015
Climate change and its impacts on river discharge in two climate regions in China
Summary: This study quantified the climate impact on river discharge in the River Huangfuchuan in semi-arid northern China and the River Xiangxi in humid southern China. Climate projections showed trends toward warmer and wetter conditions, particularly for the River Huangfuchuan. The main projected hydrologic impact was a more pronounced increase in annual discharge in both catchments. Peak flows was projected to appear earlier than usual in River Huangfuchuan and later than usual in River Xiangxi.
Hydrol. Earth Syst. Sci. Discuss., 12, 7099-7126, doi:10.5194/hessd-12-7099-2015, 2015
Effectiveness of a regional model calibrated to different parts of a flow regime in regionalisation
Summary: - Model deficiencies were identified through analysing the non-stationarity nature under different climate conditions. - Model deficiencies influenced on the identification of the relationship between the model parameters and the catchment attributes. - The parameter uncertainty in regionalisation was reduced through improving identifiability of the model parameters representing the different behaviour of the catchment. - This approach is applicable to the catchments in the monsoon areas.
Hydrol. Earth Syst. Sci. Discuss., 12, 7057-7098, doi:10.5194/hessd-12-7057-2015, 2015
Importance of maximum snow accumulation for summer low flows in humid catchments
Hydrol. Earth Syst. Sci. Discuss., 12, 7023-7056, doi:10.5194/hessd-12-7023-2015, 2015
Spatial characteristics of severe storms in Hong Kong
Summary: A storm may cause serious damage to infrastructures and public safety. The objective of this paper is to quantify the spatial characteristics of three severe storms in Hong Kong. The spatial distribution of the maximum rolling rainfall is represented by a rotated ellipsoid trend surface and a random field of residuals. The principal directions of the surface trend are between 25° and 45°. The scales of fluctuation of the residuals along eight directions are found between 5 km and 25 km.
Hydrol. Earth Syst. Sci. Discuss., 12, 6981-7021, doi:10.5194/hessd-12-6981-2015, 2015
Green and blue water footprint reduction in irrigated agriculture: effect of irrigation techniques, irrigation strategies and mulching
Summary: This paper provides the first detailed and comprehensive study regarding the potential for reducing the consumptive WF of a crop by changing management practice such as irrigation technique, irrigation strategy and mulching practice. If we consider all the cases of drip or subsurface drip irrigation with synthetic mulching, including all crops and environments, we find an average consumptive WF reduction of 28 - 29%. The corresponding blue WF reduction is 44% and the green WF reduction 14%.
Hydrol. Earth Syst. Sci. Discuss., 12, 6945-6979, doi:10.5194/hessd-12-6945-2015, 2015
Technical note: Analytical solution for the mean drawdown of steady state pumping tests in two-dimensional isotropic heterogeneous aquifers
Summary: A new method is presented which allows to interpret steady state pumping test in heterogeneous transmissivity fields. Based on a radial depending transmissivity, the effective well flow solution is derived for two cases: the ensemble mean of pumping tests and the drawdown at an individual heterogeneous transmissivity field. The analytical form of the solution allows to inversely estimate the parameters of aquifer heterogeneity (mean, variance and correlation length) from pumping test data.
Hydrol. Earth Syst. Sci. Discuss., 12, 6921-6944, doi:10.5194/hessd-12-6921-2015, 2015
Sensitivity of water stress in a two-layered sandy grassland soil to variations in groundwater depth and soil hydraulic parameters
Summary: The sensitivity of the combined model (LINGRA-N and HYDRUS-1D) to hydraulic parameters, water stress, crop yield and lower boundary conditions was assessed. We showed that it is sufficient to estimate limited amount of key parameters in optimization strategies. A combined modeling approach could increase water use efficiency (12-22.5%) and yield (5-7%) by changing irrigation scheduling. Result calls for taking into account weather forecast and soil water content data in precision agriculture.
Hydrol. Earth Syst. Sci. Discuss., 12, 6881-6920, doi:10.5194/hessd-12-6881-2015, 2015
Development and verification of a real-time stochastic precipitation nowcasting system for urban hydrology in Belgium
Summary: The Short-Term Ensemble Prediction System (STEPS) is implemented in real-time at the Royal Meteorological Institute of Belgium (STEPS-BE). The idea behind STEPS is to quantify the forecast uncertainty by adding stochastic perturbations to the deterministic extrapolation of radar images. In this paper we present the deterministic, probabilistic and ensemble verification of STEPS-BE forecasts using four precipitation cases that caused sewer system overflow in the cities of Leuven and Ghent.
Hydrol. Earth Syst. Sci. Discuss., 12, 6831-6879, doi:10.5194/hessd-12-6831-2015, 2015
The Budyko framework beyond stationarity
Summary: A major limitation of the widely-used Budyko framework is its limitation to steady-state conditions. In this study we analytically derive a new, two-parameter formulation of the Budyko framework that allows for non-stationary conditions. We further show by using global, standard gridded estimates of precipitation, evapotranspiration and potential evaporation, that the new formulation is capable to represent first-order seasonal dynamics within the hydroclimatological system.
Hydrol. Earth Syst. Sci. Discuss., 12, 6799-6830, doi:10.5194/hessd-12-6799-2015, 2015
Distributed model of hydrological and sediment transport processes in large river basins in Southeast Asia
Summary: The uniqueness of this sediment model is the ability to simulate the sediment transport processes separately on hillslope and in river channel in each grid within a large river basin. The sub-model of river channel is able to simulate deposition and detachment using relevant physical equations. This model can identify the locations of severe sediment dynamics occurred by a fine grid scale and can output spatial distribution of soil erosion sediment transport and deposition in entire river basin.
Hydrol. Earth Syst. Sci. Discuss., 12, 6755-6797, doi:10.5194/hessd-12-6755-2015, 2015
The Hydrological Open Air Laboratory (HOAL) in Petzenkirchen: a hypotheses driven observatory
Summary: This paper illustrates the experimental and monitoring setup of the 66 ha Hydrological Open Air Laboratory (HOAL) in Petzenkirchen, Lower Austria, which allows meaningful hypothesis testing. The HOAL catchment features a range of different runoff generation processes (surface runoff, springs, tile drains, wetlands), and is convenient from a logistic point of view as all instruments can be connected to the power grid and a high speed glassfibre Local Area Network.
Hydrol. Earth Syst. Sci. Discuss., 12, 6683-6753, doi:10.5194/hessd-12-6683-2015, 2015
Spatio-temporal assessment of WRF, TRMM and in situ precipitation data in a tropical mountain environment (Cordillera Blanca, Peru)
Summary: Three different types of gridded precipitation products are compared in a high glaciated tropical mountain environment (Cordillera Blanca, Peru): ground based interpolation, satellite derived product (TRMM3B42), and outputs from the regional climate model WRF. While none of the products meets the challenge of representing both accumulated quantities and frequency of occurrence at the short time scale, we concluded that new methods should be used to merge those various precipitation products.
Hydrol. Earth Syst. Sci. Discuss., 12, 6635-6681, doi:10.5194/hessd-12-6635-2015, 2015
Investigating the impact of land-use land-cover change on Indian summer monsoon daily rainfall and temperature during 1951–2005 using a regional climate model
Summary: Regional climate model (RegCM4) simulations demonstrate that part of the observed decrease in moderate rainfall events during summer monsoon season over central India from 1951 to 2005 is attributed to anthropogenically induced land-use land-cover change (LULCC). LULCC also explains a warming in the daily mean and maximum temperature by 1-1.2oC, that is comparable with the observed increasing trend. This study shows the importance of LULCC in the context of regional climate change over India.
Hydrol. Earth Syst. Sci. Discuss., 12, 6575-6633, doi:10.5194/hessd-12-6575-2015, 2015
Estimating spatially distributed soil water content at small watershed scales based on decomposition of temporal anomaly and time stability analysis
Summary: Spatiotemporal SWC was decomposed into into three terms (spatial forcing, temporal forcing, and interactions between spatial and temporal forcing) for near surface and root zone; Empirical orthogonal function indicated that underlying patterns exist in the interaction term at small watershed scales; Estimation of spatially distributed SWC benefits from decomposition of the interaction term; The suggested decomposition of SWC with time stability analysis has potential in SWC downscaling.
Hydrol. Earth Syst. Sci. Discuss., 12, 6467-6503, doi:10.5194/hessd-12-6467-2015, 2015
Linking biogeochemistry to hydro-geometrical variability in tidal estuaries: a generic modeling approach
Summary: A generic estuarine model is applied to three idealized tidal estuaries representing the main hydro-geometrical estuarine classes. The study provides insight on the estuarine biogeochemical dynamics, in particular the air-water CO2 flux, as well as on the potential response to future environmental changes and to uncertainties in model parameter values. We believe that our approach could help improving upscaling strategies to better integrate estuaries in regional/global biogeochemical studies.
Hydrol. Earth Syst. Sci. Discuss., 12, 6351-6435, doi:10.5194/hessd-12-6351-2015, 2015
Land-use changes reinforce the impacts of climate change on annual runoff dynamics in a southeast China coastal watershed
Summary: The L-R diagram was developed to reveal that land-use changes has reinforced the impact of climate changes on annual runoff dynamic in a Southeast China coastal watershed. Deforestation played significant role to generate overflow runoff in a watershed during heavy precipitation. In contrast, reforestation enabled watershed to store more water in a catchment during dry year. This study inferred that severe drought and flood in the future cannot be fully addressed as an impact of climate changes.
Hydrol. Earth Syst. Sci. Discuss., 12, 6305-6325, doi:10.5194/hessd-12-6305-2015, 2015
Initial assessment of a multi-model approach to spring flood forecasting in Sweden
Summary: New approaches to spring flood forecasting, that reflect the latest developments with respect to analysis and modelling on seasonal time scales, are presented and evaluated. Three main approaches, represented by specific methods, are evaluated in spring-flood hindcasts for three Swedish rivers over a 10-year period. When combining all forecasts in a weighted multi-model approach, a mean improvement over all locations and lead times of nearly 10% was indicated, as compared with today's approach.
Hydrol. Earth Syst. Sci. Discuss., 12, 6077-6113, doi:10.5194/hessd-12-6077-2015, 2015
Estimation of flood warning runoff thresholds in ungauged basins with asymmetric error functions
Hydrol. Earth Syst. Sci. Discuss., 12, 6011-6041, doi:10.5194/hessd-12-6011-2015, 2015
The cost of ending groundwater overdraft on the North China Plain
Hydrol. Earth Syst. Sci. Discuss., 12, 5931-5966, doi:10.5194/hessd-12-5931-2015, 2015
South Asia river flow projections and their implications for water resources
Summary: South Asia is a highly variable region where there is concern over water and food security. The simulations presented suggest an increasing trend in water resources, in some cases almost doubling by the end of the century although this is masked by the large annual variability of river flows for this region. Future peak river flows still occur during the Monsoon period, with a tendancy for reduced frequency of lowest flows and increased magnitude of highest flows across the selected locations.
Hydrol. Earth Syst. Sci. Discuss., 12, 5789-5840, doi:10.5194/hessd-12-5789-2015, 2015
Trends in West African floods: a comparative analysis with rainfall and vegetation indices
Hydrol. Earth Syst. Sci. Discuss., 12, 5083-5121, doi:10.5194/hessd-12-5083-2015, 2015
Uncertainty analysis for evaluating the accuracy of snow depth measurements
Hydrol. Earth Syst. Sci. Discuss., 12, 4157-4190, doi:10.5194/hessd-12-4157-2015, 2015
On the spatial organization of the ridge slough patterned landscape
Hydrol. Earth Syst. Sci. Discuss., 12, 2975-3010, doi:10.5194/hessd-12-2975-2015, 2015