A salinity module for SWAT to simulate salt ion fate and transport at the watershed scale Hydrology and Earth System Sciences DOI 10.5194/hess-23-3155-2019 31 July 2019 Salinity is one of the most common water quality threats in river basins and irrigated regions worldwide. Available watershed models, however, do not simulate the fate and transport of salt species. This paper presents a modified version of the popular SWAT watershed model that simulates the transport of major salt ions in a watershed system. Salt is transported via surface runoff, soil percolation, groundwater flow, and streamflow. The model can be used in salt-affected watersheds worldwide. Read more
Assessing the characteristics and drivers of compound flooding events around the UK coast Hydrology and Earth System Sciences DOI 10.5194/hess-23-3117-2019 23 July 2019 Flooding can arise from multiple sources, including waves, extreme sea levels, rivers, and severe rainfall. When two or more sources combine, the consequences can be greatly multiplied. We find the potential for the joint occurrence of extreme sea levels and river discharge to be greater on the western coast of the UK compared to the eastern coast. This is due to the weather conditions generating each flood source around the UK. These results will help increase our flood forecasting ability. Read more
Technical note: A microcontroller-based automatic rain sampler for stable isotope studies Hydrology and Earth System Sciences DOI 10.5194/hess-23-2637-2019 19 June 2019 Most commercial automatic rain samplers are costly and do not prevent evaporation from the collection bottles. Hence, we have developed a microcontroller-based collector enabling timer-actuated integral rain sampling. The simple, low-cost device is robust and effectively minimizes post-sampling evaporation. The excellent performance of the collector during an evaporation experiment in a lab oven suggests that even multi-week field deployments in warm climates are feasible. Read more
Using a coupled agent-based modeling approach to analyze the role of risk perception in water management decisions Hydrology and Earth System Sciences DOI 10.5194/hess-23-2261-2019 10 May 2019 This study applies a two-way coupled agent-based model (ABM) with a river-reservoir management model (RiverWare) to analyze the role of risk perception in water management decisions using the Bayesian inference mapping joined with the cost–loss model. The calibration results capture the dynamics of historical irrigated area and streamflow changes and suggest that the proposed framework improves the representation of human decision-making processes compared to conventional rule-based ABMs. Read more
Controls on spatial and temporal variability in streamflow and hydrochemistry in a glacierized catchment Hydrology and Earth System Sciences DOI 10.5194/hess-23-2041-2019 24 April 2019 Hydrometric and geochemical dynamics are controlled by interplay of meteorological conditions, topography and geological heterogeneity. Nivo-meteorological indicators (such as global solar radiation, temperature and decreasing snow depth) explain monthly conductivity and isotopic dynamics best. These insights are important for better understanding hydrochemical responses of glacierized catchments under a changing cryosphere. Read more
Geostatistical interpolation by quantile kriging Hydrology and Earth System Sciences DOI 10.5194/hess-23-1633-2019 20 March 2019 Many variables, e.g., in hydrology, geology, and social sciences, are only observed at a few distinct measurement locations, and their actual distribution in the entire space remains unknown. We introduce the new geostatistical interpolation method ofquantile kriging, providing an improved estimator and associated uncertainty. It can also host variables, which would not fulfill the implicit presumptions of the traditional geostatistical interpolation methods. Read more
Attributing the 2017 Bangladesh floods from meteorological and hydrological perspectives Hydrology and Earth System Sciences DOI 10.5194/hess-23-1409-2019 13 March 2019 In August 2017 Bangladesh faced one of its worst river flooding events in recent history. For the large Brahmaputra basin, using precipitation alone as a proxy for flooding might not be appropriate. In this paper we explicitly test this assumption by performing an attribution of both precipitation and discharge as a flooding-related measure to climate change. We find the change in risk to be of similar order of magnitude (between 1 and 2) for both the meteorological and hydrological approach. Read more
Effects of univariate and multivariate bias correction on hydrological impact projections in alpine catchments Hydrology and Earth System Sciences DOI 10.5194/hess-23-1339-2019 11 March 2019 Several multivariate bias correction methods have been developed recently, but only a few studies have tested the effect of multivariate bias correction on hydrological impact projections. This study shows that incorporating or ignoring inter-variable relations between air temperature and precipitation can have a notable effect on the projected snowfall fraction. The effect translated to considerable consequences for the glacio-hydrological responses and streamflow components of the catchments. Read more
Conservative finite-volume forms of the Saint-Venant equations for hydrology and urban drainage Hydrology and Earth System Sciences DOI 10.5194/hess-23-1281-2019 7 March 2019 A new derivation of the equations for one-dimensional open-channel flow in rivers and storm drainage systems has been developed. The new approach solves some long-standing problems for obtaining well-behaved solutions with conservation forms of the equations. This research was motivated by the need for highly accurate models of large-scale river networks and the storm drainage systems in megacities. Such models are difficult to create with existing equation forms. Read more
Seasonal origins of soil water used by trees Hydrology and Earth System Sciences DOI 10.5194/hess-23-1199-2019 1 March 2019 We used stable isotopes of xylem water to study differences in the seasonal origin of water in more than 900 individual trees from three dominant species in 182 Swiss forested sites. We discovered that midsummer transpiration was mostly supplied by winter precipitation across diverse humid climates. Our findings provide new insights into tree vulnerability to droughts, transport of water (and thus solutes) in soils, and the climatic information conveyed by plant-tissue isotopes. Read more