Teaching hydrological modelling: illustrating model structure uncertainty with a ready-to-use computational exercise

Estimating the impact of different sources of uncertainty along the modelling chain is an important skill graduates are expected to have. Broadly speaking, educators can cover uncertainty in hydrological modelling by differentiating uncertainty in data, model parameters and model structure. This provides students with insights on the impact of uncertainties on modelling results and thus on the usability of the acquired model simulations for decision making. A survey among teachers in the Earth and environmental sciences showed that model structural uncertainty is the least represented uncertainty group in teaching. This paper introduces a computational exercise that introduces students to the basics of model structure uncertainty through two ready-to-use modelling experiments. These experiments require either Matlab or Octave, and use the open-source Modular Assessment of Rainfall-Runoff Models Toolbox (MARRMoT) and the open-source Catchment Attributes and Meteorology for Large-sample Studies (CAMELS) data set. The exercise is short and can easily be integrated into an existing hydrological curriculum, with only a limited time investment needed to introduce the topic of model structure uncertainty and run the exercise. Two trial applications at the Technische Universität Dresden (Germany) showed that the exercise can be completed in two afternoons or four 90 min sessions and that the provided setup effectively transfers the intended insights about model structure uncertainty

When good signatures go bad: Applying hydrologic signatures in large sample studies

Hydrologic signatures are quantitative metrics that describe streamflow statistics and dynamics. Signatures have many applications, including assessing habitat suitability and hydrologic alteration, calibrating and evaluating hydrologic models, defining similarity between watersheds and investigating watershed processes. Increasingly, signatures are being used in large sample studies to guide flow management and modelling at continental scales. Using signatures in studies involving 1000s of watersheds brings new challenges as it becomes impractical to examine signature parameters and behaviour in each watershed. For example, we might wish to check that signatures describing flood event characteristics have correctly identified event periods, that signature values have not been biassed by data errors, or that human and natural influences on signature values have been correctly interpreted. In this commentary, we draw from our collective experience to present case studies where naïve application of signatures fails to correctly identify streamflow dynamics. These include unusual precipitation or flow regimes, data quality issues, and signature use in human‐influenced watersheds. We conclude by providing guidance and recommendations on applying signatures in large sample studies

Twenty-three unsolved problems in hydrology (UPH) – a community perspective

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through on-line media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focussed on process-based understanding of hydrological variability and causality at all space and time scales. Increased attention to environmental change drives a new emphasis on understanding how change propagates across interfaces within the hydrological system and across disciplinary boundaries. In particular, the expansion of the human footprint raises a new set of questions related to human interactions with nature and water cycle feedbacks in the context of complex water management problems. We hope that this reflection and synthesis of the 23 unsolved problems in hydrology will help guide research efforts for some years to come

Mimicry of a conceptual hydrological model (HBV): what's in a name?

Models that mimic an original model might have a different model structure than the original model, that affects model output. This study assesses model structure differences and their impact on output by comparing 7 model implementations that carry the name HBV. We explain and quantify output differences with individual model structure components at both the numerical (e.g., explicit/implicit scheme) and mathematical level (e.g., lineair/power outflow). It was found that none of the numerical and mathematical formulations of the mimicking models were (originally) the same as the benchmark, HBV-light. This led to small but distinct output differences in simulated streamflow for different numerical implementations (KGE difference up to 0.15), and major output differences due to mathematical differences (KGE median loss of 0.27). These differences decreased after calibrating the individual models to the simulated streamflow of the benchmark model. We argue that the lack of systematic model naming has led to a diverging concept of the HBV-model, diminishing the concept of model mimicry. Development of a systematic model naming framework, open accessible model code and more elaborate model descriptions are suggested to enhance model mimicry and model development

Detached house

Předmětem bakalářské práce je návrh a vypracování studie a projektu pro provádění stavby pro rodinný dům s provozovnou v lokalitě Brno Mokrá Hora. Provozovnu tvoří výdejní místo pro online obchod. Budova sestává z polozapušťeného suterénu jednoho nadzemního podlaží. Bude sloužit jako trvalé bydlení pro čtyřčlennou rodinu a pracoviště pro dva zaměstnance. Stěny bude tvořit vápenopískové zdivo s kontaktním zateplovacím systémem ETICS, stropy budou železobetonové a střecha plochá vegetační. Součástí návrhu je také parkoviště pro dva osobní automobily a jedno lehké užitkové vozidlo. Zajímavost řešení spočívá ve výškové poloze střechy, nachází se totiž v úrovni místní komunikace. Projekt pro provádění stavby byl zpracován v programu AutoCAD, studie a vizualizace pomocí programů ArchiCAD a Artlantis 5.The subject of this bachelors thesis was to design a single-family house in Brno Mokrá Hora and process the study and the design documentation for this house. Part of it will serve as permanent housing for a 4 member family and the second part as a distribution point for an online shop with 2 employees. The walls will consist of sand-lime bricks with an additional contact thermal insulation system ETICS, the ceiling will be reinforced concrete constructions and the house will have a walkable flat green roof. Part of the documentation is also the modification design of the surrounding terrain and the design of the car park for 2 cars and 1 light commercial vehicle. An interesting design choice is the height level of the roof, which is situated in the same level as the local road. Design documentation was processed using the program AutoCAD, the study and the visualization using both ArchiCAD and Artlantis 5.