In recent decades considerable progress has been made in climate model development. Following the massive increase computational power, models became more sophisticated. At same time also simple conceptual have advanced. this study we validate and compare three hydrological of different complexity to investigate whether their performance varies accordingly. For purpose use runoff soil moisture measurements, which allow a truly independent validation, from several sites across Switzerland....

One of the most important functions catchments is storage water. Catchment buffers meteorological extremes and interannual streamflow variability, controls partitioning between evaporation runoff, influences transit times Hydrogeological data to estimate are usually scarce seldom available for a larger set catchments. This study focused on in prealpine alpine catchments, using 21 Swiss comprising different elevation ranges. comparisons depend definitions. defines types including definitions...

Abstract. Low flows are often poorly reproduced by commonly used hydrological models, which traditionally designed to meet peak flow situations. Hence, there is a need improve models for low prediction. This study assessed the impact of model structure on simulations and recession behaviour using Framework Understanding Structural Errors (FUSE). FUSE identifies set subjective decisions made when building provides multiple options each modeling decision. Altogether 79 were created applied...

Abstract The Standardized Precipitation Index ( SPI ) is the most widely used index to characterize droughts that are related precipitation deficiencies. However, does not always deliver relevant information for hydrological drought management particularly in snow‐influenced catchments. If temporarily stored as snow, then there a significant difference between meteorological and because delayed release of melt water stream. We introduce an extension , Snow Melt Rain SMRI ), accounts rain...

Abstract It is expected that an increasing proportion of the precipitation will fall as rain in alpine catchments future. Consequently, snow storage to decrease, which, together with changes snowmelt rates and timing, might cause reductions spring summer low flows. The objectives this study were (1) simulate effect changing on flows during warm seasons (2) relate drought sensitivity simulated at different elevations. Swiss Climate Change Scenarios 2011 data set was used derive future air...

Abstract. In this study, we analyze how precipitation, antecedent conditions, and their spatial patterns interactions lead to extreme floods in a large catchment. The analysis is based on 10 000 years of continuous simulations from hydro-meteorological modelling chain for catchment, the Aare River basin, Switzerland. To account different flood-generating processes, our work with hourly time resolution. consisted stochastic weather generator (GWEX), bucket-type hydrological model (HBV),...

Abstract. Winter snow accumulation obviously has an effect on the following catchment runoff. The question is, however, how long this lasts and important it is compared to rainfall inputs. Here we investigate relative importance of one critical aspect runoff, namely summer low flow. This especially relevant as expected increase air temperature might result in decreased storage. A decrease will affect soil groundwater storages during spring cause streamflow values subsequent warm season. To...

Good representation of the hydrological system in models is required to provide reliable predictions. The selection a suitable set performance criteria core decision identifying optimal parameter set(s) during model calibration. As each criterion focuses on different parts hydrograph, their often determines which values are selected as for representing rainfall-runoff behaviour catchment. Knowning most purpose, or catchment difficult determine.We therefore 16 classical metrics and signature...

To calculate annual values for the water balance, year (or hydrological year) is usually used instead of calendar year. This done to avoid that precipitation from one influences runoff in following In snow-dominated catchments northern hemisphere, example, such a carryover would occur regularly if were aggregate data. ensure snow melts which it fell, calculations are based on years start early fall (e.g., October 1 or November 1). other climates, different used, e.g., does not middle monsoon...

Dealing with large uncertainties associated estimates of extreme floods is a major challenge for risk assessment and mitigation. It important to understand quantify the potential sources these reduce support cost-effective safe infrastructure design.In this study, we employ framework based on hydrometeorological modeling chain long continuous simulations estimate (Viviroli et al., 2022). The first element multi-site stochastic weather generator GWEX, which focuses intense precipitation...

In the era of large-sample hydrology (LSH), there is still a lack in availability consistent data related to water quality. To address this gap, we introduce CAMELS-CH-Chem, dataset inspired by recently published CAMELS-Chem for contiguous United States. CAMELS-CH-Chem extends CAMELS-CH (Catchment Attributes and Meteorology Large-sample Studies Switzerland) integrating stream chemical parameters atmospheric deposition 115 monitoring stations across Switzerland. Spanning same period as...

Abstract. A widespread assumption is that data-driven models only achieve good results with sufficiently large training data, while process-based are usually expected to be superior in data-poor situations. In our study, we investigate this by calibrating several and hydrological data sets of observed discharge differ the number points type selection. The tested include four commonly used (GR4J, HBV, mHM, SWAT+) (conditional probability distributions, regression trees, ANN, LSTM), which...

Abstract. Meteorological droughts like those in summer 2003 or spring 2011 Europe are expected to become more frequent the future. Although spatial extent of these drought events was large, not all regions were affected same way. Many catchments reacted strongly meteorological showing low levels streamflow and groundwater, while others hardly reacted. Also, hydrological for specific different between two historical due initial conditions propagation processes. This leads important question...

Abstract. Precipitation deficits and temperature anomalies are often the main cause for low flows summer streamflow droughts. However, where groundwater is contribution to sustain water availability ecological integrity during dry spells, role of recharge catchment storage crucial understand drought sensitivity. Here we introduce stress tests as complement climate scenarios characterize quantify sensitivities catchments. The presented by applying them six headwater catchments in Switzerland...

Abstract. Estimates for rare to very floods are limited by the relatively short streamflow records available. Often, pragmatic conversion factors used quantify such events based on extrapolated observations, or simplifying assumptions made about extreme precipitation and resulting flood peaks. Continuous simulation (CS) is an alternative approach that better links estimation with physical processes avoids antecedent conditions. However, long-term CS has hardly been implemented estimate (i.e....

Abstract. In this study, we analyze how precipitation, antecedent conditions, and their spatial patterns interactions lead to extreme floods in a large catchment. The analysis is based on 10,000 years of continuous simulations from hydro-meteorological model chain for catchment, the Aare river basin, Switzerland. To account different flood-generating processes, our work with hourly time resolution. consisted stochastic weather generator (GWEX), bucket-type hydrological (HBV), routing system...

Hourly values of evapotranspiration (ET) for the months July to September 1976 and 1977 were calculated from energy balance measurements at two test sites near village Obergurgl in Austrian Alps. One site was situated 1,960 m a.s.l. on a cultivated meadow timberline, other 2,580 covered with alpine sedges grasses. Examples daily variations sums fluxes are presented clear cloudy days. The mean courses ET shown every month measurement periods; differences between related decrease transpirating...

Abstract. Low flows are often poorly reproduced by commonly used hydrological models, which traditionally designed to meet peak flow situations. Hence, there is a need improve models for low prediction. This study assessed the impact of model structure on simulations and recession behaviour using Framework Understanding Structural Errors (FUSE). FUSE identifies set subjective decisions made when building model, provides multiple options each modeling decision. Altogether 79 were created...

Abstract In most bucket‐type hydrological models, water can only flow from the groundwater to stream and flux is based on storage. However, many catchments have losing sections, where streamflow recharges groundwater. We developed a formulation represent recharge by streamwater in model tested this for Panola Mountain Research Watershed demonstrate its function assess performance. The upper reach of catchment often dry highly affected bedrock outcrop; further downstream perennial. simulated...