Interactions between soil moisture and terrestrial evaporation affect responses between land surface and the atmosphere across scales. We present an analysis of the link between soil moisture and evaporation estimates from three distinct models. The relationships were examined over nearly 2 years of observation data. Results show that while direct correlations of raw data were mostly not useful, the root-zone soil moisture and the modelled evaporation estimates reflect similar distributions.

Unmanned aerial vehicles (UAVs) have the potential to capture information about the earth’s surface in dangerous and previously inaccessible locations. Here we present a method whereby image acquisition and subsequent analysis have enabled the highly dynamic and oft-immeasurable hydraulic phenomenon present during high-energy flash floods to be quantified at previously unattainable spatial and temporal resolutions.

Quantification of rapid flow of water and associated transport of contaminants through large soil pores generated by earthworms or decaying plant roots is of crucial importance for sustaining both soil and water quality. Advanced visualization and analysis techniques based on state-of-the-art X-ray computed tomography have been applied to 65 soil cores extracted from an agricultural field in Silstrup, Denmark, to improve models for the prediction of fast, preferential flow processes in soils.

A comprehensive and detailed data set of the salinity distribution over an entire year in a complex and dynamic (because heavily utilized and modified) deltaic river system was thoroughly analysed, and formed the basis for a validated analytical model that can predict the extent of seawater among other salinity sources in an estuary. The procedure can be applied to other estuaries.

Very few studies have applied a physically based hydrological model with integrated and distributed multivariate observation data of both flow and transport phenomena. In this study we address this challenge for a hillslope-scale unsaturated zone isotope tracer experiment. The results show how model complexity evolves as the number and detail of simulated responses increases. Possible gaps in process representation for simulating solute transport phenomena in very dry soils are discussed.

Games are an optimal way to teach about water resource sharing, as they allow real-world scenarios to be explored. We look at how games can be used to teach about water resource sharing, by both playing and developing water games. An evaluation of the web-based game Irrigania found Irrigania to be an effective and easy tool to incorporate into curriculum, and a course on developing water games encouraged students to think about water resource sharing in a more critical and insightful way.

The effects of human actions in small-scale water development initiatives and the associated hydrological research activities are basically unspecified. We argue that more explicit attention helps to design more appropriate answers to the challenges faced in field studies. A more systematic approach is proposed that would be useful when designing field projects: two sets of questions on (1) dealing with surprises and (2) cost–benefits of data gathering.

Australian seasonal streamflow forecasts are issued by the Bureau of Meteorology with up to two weeks' delay. Timelier forecast release will enhance forecast value and enable sub-seasonal forecasting. The bureau's forecasting approach is modified to allow timelier forecast release, and changes in reliability and skill are quantified. The results are combined with insights into the forecast production process to recommend a more flexible forecasting system to better meet the needs of users.

Using a weather model, we find that historic and future land use changes have a smaller effect (decrease) on summer precipitation in the Netherlands than climate change has (increase). As a result, precipitation will likely continue to increase over the coming decades. Nevertheless, in the Netherlands the influence of land surface changes on summer precipitation is not negligible and counters the effect of climate change, especially for extreme precipitation.

Although seawater desalination has been widely implemented and used as a key source of water in arid regions, it has been seldom included in global water resource assessments based on numerical simulations. We first developed a global model to estimate the areal extent and production of seawater desalination which was designed to be incorporated with global hydrological models. The model was applied to future periods under three distinct socioeconomic conditions.

We compare seven meteorological drought indices that are commonly used to predict future droughts. Our goal is to assess the reliability of these indices to predict hydrological impacts of droughts under changing climatic conditions, using an integrated hydrological model. Drought indices are able to identify the timing of hydrological impacts of droughts in present and future climate. However, these indices can not estimate the severity of hydrological impacts of droughts in future climate.

We show that the derived distribution approach is able to characterize the interannual variability of precipitation much better than fitting a probabilistic model to annual rainfall totals, as long as continuously gauged data are available. The method is a useful tool for describing temporal changes in the distribution of annual rainfall, as it works for records as short as 5 years, and therefore does not require any stationarity assumption over long periods.

Soil moisture is a crucial variable for a variety of applications, ranging from weather forecasting and agricultural production to the monitoring of floods and droughts. Satellite observations are particularly important in regions where no in situ measurements are available. Our study presents a method to integrate global near-real-time satellite observations from different sensors into one harmonized, daily data set. A first validation shows good results on a global scale.

We performed and evaluated a pulse injection tracer test in an artificial recharge system to understand the fate of potential contaminants. A 2-D multilayer model (under homogeneous and heterogeneous medium hypothesis) was used to evaluate the measured breakthrough curves at six points. Both homogeneous and heterogeneous models reproduce the long tails observed. This implies that the shapes of the breakthrough curves are caused not only by heterogeneity, but also by the mean flow structure.

Virtual water trade (VWT) embedded in crop trade is an important component of water management. Vulnerable importers in VWT were classified through connectivity and volume of VWT using degree centrality of a VWT network. Influential traders on entire VWT were classified through eigenvector centrality of a VWT network.

While quantifying vegetation water use over multiple plant function types in the Amazon Basin, we found substantial biophysical control during drought as well as a water-stress period and dominant climatic control during a water surplus period. This work has direct implication in understanding the resilience of the Amazon forest in the spectre of frequent drought menace as well as the role of drought-induced plant biophysical functioning in modulating the water-carbon coupling in this ecosystem.

This paper identifies periods of recovery from drought in 52 river flow records from the UK between 1883 and 2013. The approach detects 459 events that vary in space and time. This large dataset allows individual events to be compared with others in the historical record. The ability to objectively appraise contemporary events against the historical record has not previously been possible, and may allow water managers to prepare for a range of outcomes at the end of a drought.

To understand past flood changes in the Rhine catchment and the role of anthropogenic climate change in extreme flows, an attribution study relying on a proper GCM (general circulation model) downscaling is needed. A downscaling based on conditioning a stochastic weather generator on weather patterns is a promising approach. Here the link between patterns and local climate is tested, and the skill of GCMs in reproducing these patterns is evaluated.

The paper is focused on assessment of the contribution of various sources of uncertainty to the estimated rainfall erosivity factor. It is shown that the rainfall erosivity factor can be estimated with reasonable precision even from records shorter than recommended, provided good spatial coverage and reasonable explanatory variables are available. The research was done as an update of the R factor estimates for the Czech Republic, which were later used for climate change assessment.

The remaining populations of the endangered dwarf wedgemussel (DWM) (Alasmidonta heterodon) in the upper Delaware River, northeastern USA, were thought to be located in areas of substantial groundwater discharge to the river. Physical, thermal, and geophysical methods applied at several spatial scales indicate that DWM are located within or directly downstream of areas of substantial groundwater discharge to the river. DWM may depend on groundwater discharge for their survival.

We present a method to assimilate observed groundwater head and soil moisture profiles into an integrated hydrological model. The study uses the ensemble transform Kalman filter method and the MIKE SHE hydrological model code. The proposed method is shown to be more robust and provide better results for two cases in Denmark, and is also validated using real data. The hydrological model with assimilation overall improved performance compared to the model without assimilation.

We present novel research on the seasonal dynamics of the impact of rainfall (R-factor) on the mobilization of topsoil as soil erosion by water for Switzerland. A modeling approach was chosen that enables the dynamical mapping of the R-factor. Based on the maps and modeling results, we could investigate the spatial and temporal distribution of that factor, which is high for Switzerland. With these results, agronomists can introduce selective erosion control measures.

We want to know how combined snow water equivalent (SWE) and streamflow data assimilation (DA) impacts streamflow predictions and how it compares with DA of SWE only and streamflow only. Results show that streamflow DA positively impacts short-term streamflow forecasts, while the impact of SWE DA lasts over a much longer horizon. Simultaneous DA of both SWE and streamflow performs better than its individual counterparts at all forecast horizons.

The study presents a rapid, robust and reproducible approach to select optimum inputs for hydrological models. We show significant variation in pre-calibrated model performance due to the choice of different combinations of land-use, soil and weather datasets, particularly in data-scarce regions most in need of computationally-efficient approaches to optimise reliability of models and support decision-making. Our case study is directly relevant to planners and decision-makers in Wala, Jordan.