The Alps are a key water resource for central Europe, providing water for drinking, agriculture, and hydropower production. To assess water availability in streams, we need to understand how much streamflow is derived from old water stored in the subsurface versus more recent precipitation. We use tracer data from 32 Alpine streams and statistical tools to assess how much recent precipitation can be found in Alpine rivers and how this amount is related to catchment properties and climate.

Monitoring agricultural drainage flow in irrigated areas is key to water and soil management. In this paper, four simple drainage models are evaluated on two irrigated sub-basins where drainage flow is measured daily. The evaluation of their precision shows that they simulate drainage very well when calibrated with drainage data and that one of them is slightly better. The evaluation of their accuracy shows that only one model can provide rough drainage estimates without calibration data.

The entropy model is a reliable tool to estimate flood discharge in rivers using observed level and surface velocity. Often, level and velocity sensors are placed on bridges, which may disturb the flow. Using accurate numerical models, we explored the entropy model reliability nearby a multi-arch bridge. We found that it is better to place sensors and to estimate the discharge upstream of bridges; downstream, the entropy model needs the river-wide distribution of surface velocity as input data.

Faced with the problem of uncertainty in the field of water resources management, this paper proposes the Copula Multi-objective Robust Optimization and Probabilistic Analysis of Robustness (CM-ROPAR) approach to obtain robust water allocation schemes based on the uncertainty of drought and wet encounters and the uncertainty of inflow. We believe that this research article not only highlights the significance of the CM-ROPAR approach but also provides a new concept for uncertainty analysis.

We use grid-based runoff from a hydrological model to identify large spatiotemporally connected flood events in Europe, assess extent trends over the last 70 years, and attribute the trends to different drivers. Our findings reveal a general increase in flood extent, with regional variations driven by diverse factors. The study not only enables a thorough examination of flood events across multiple basins but also highlights the potential challenges arising from changing flood extents.

The accurate estimation of precipitation and its spatial variability within a watershed is crucial for reliable discharge simulations. The study is the first detailed analysis of the potential usage of the cellular automata technique to merge different rainfall data inputs to hydrological models. This work shows an improvement in the performance of hydrological simulations when satellite and rain gauge data are merged.

The understanding of spatio-temporal variability of evapotranspiration (ET) is currently limited by a lack of measurement techniques that are low cost and that can be applied anywhere at any time. Here we show that evapotranspiration can be estimated accurately using observations made by smartphone sensors, suggesting that smartphone-based ET monitoring could provide a realistic and low-cost alternative for real-time ET estimation in the field.

The H₂Ours game is designed to facilitate knowledge transfer and sharing among stakeholders to trigger commitment and collaborative action to restore hydrological conditions. The adaptability of the H₂Ours game was proven in two different landscapes: groundwater recharge in upper to middle sub-watersheds with (over)use of water in the lowland zone and a peatland with drainage, rewetting, oil palm conversion and fire as issues. The game evaluation shows that the H₂Ours game meets its purpose.

Rainfall input generally controls soil water and plant growth. We focus on rainfall redistribution in succession sequence forests over 22 years. Some changes in rainwater volume and chemistry in the throughfall and stemflow and drivers were investigated. Results show that shifted open rainfall over time and forest factors induced remarkable variability in throughfall and stemflow, which potentially makes forecasting future changes in water resources in the forest ecosystems more difficult.

Snow cover is an important variable when studying the effect of climate change in the Arctic. Therefore, the correct detection of snowfall is important. In this study, we present methods to detect snowfall accurately using satellite observations. The snowfall event detection results of our limited area are encouraging. We find that further development could enable application over the whole Arctic, providing necessary information on precipitation occurrence over remote areas.

This study developed a framework to understand the structures of knowledge development in 72 river basins globally from 1962–2017 using Web of Science. It was found that the knowledge systems were characterized by increasingly interconnected management issues addressed by limited disciplines and were linked more strongly to societal impacts than that to policy. Understanding the current state of knowledge casts a light on sustainable knowledge transformations for river basin management.

An integrated cryospheric–hydrologic model, FLEX-Cryo, was developed that considers glaciers, snow cover, and frozen soil and their dynamic impacts on hydrology. We utilized it to simulate future changes in cryosphere and hydrology in the Hulu catchment. Our projections showed the two glaciers will melt completely around 2050, snow cover will reduce, and permafrost will degrade. For hydrology, runoff will decrease after the glacier has melted, and permafrost degradation will increase baseflow.

A coupled statistical–hydrodynamic model framework is employed to quantitatively evaluate the sensitivity of compound flood hazards to the relative timing of peak storm surges and rainfall. The findings reveal that the timing difference between these two factors significantly affects flood inundation depth and extent. The most severe inundation occurs when rainfall precedes the storm surge peak by 2 h.

This work details the temperature and related variables of several High Arctic ponds in the Nanuit Itillinga (Polar Bear Pass) National Wildlife Area through nine seasons. The ponds show much variability in their temperature patterns over time and space. Ponds normally reached 10–15 °C for parts of the summer except in 2013, a cold summer season in which pond temperatures never exceeded 5 °C. This study contributes to the ongoing discussion of climate warming and its impact on Arctic landscapes.

Runoff and sediment reduction benefits of hillside mixed grasslands were examined. Cultivated grasslands effectively increased runoff and decreased sediment along ages. Runoff was the dominant factor affecting the soil erosion modulus on alpine hillsides. This implies that protective measures should be prioritized during the initial planting stage of cultivated grasslands on degraded alpine hillsides.