@inproceedings{HeMolkenthinWendlandetal., author = {He, Qianwen and Molkenthin, Frank and Wendland, Frank and Herrmann, Frank}, title = {Evaluation of different interpolation schemes for precipitation and reference evapotranspiration and the impact on simulated large-scale water balance in Slovenia}, series = {European Geosciences Union, General Assembly 2016, Vienna, Austria}, booktitle = {European Geosciences Union, General Assembly 2016, Vienna, Austria}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, abstract = {Precipitation and reference evapotranspiration (ET0) are two main climate input components for hydrological models, which are often recorded or calculated based on measuring stations. Interpolation schemes are implemented to regionalize data from measuring stations for distributed hydrological models. This study had been conducted for 5 months, with the aim of: (1) evaluating three interpolation schemes for precipitation and reference evapotranspiration (ET0); (2) assessing the impact of the interpolation schemes on actual evapotranspiration and total runoff simulated by a distributed large-scale water balance model - mGROWA. The study case was the Republic of Slovenia, including a high variability in topography and climatic conditions, with daily meteorological data measured in 20 stations for a period of 44 years. ET0 were computed by both FAO Penman-Monteith equation and Hargreaves equation. The former equation is recommended as the standard equation, while the ET0 calculated by the latter one for Slovenia had a certain deviation (+150 mm/a) from it. Ordinary Kriging, Regression Kriging and Linear Regression were selected to regionalize precipitation and ET0. Reliability of the three interpolation schemes had been assessed based on the residual obtained from cross-validation. Monthly regionalized precipitation and ET0 were subsequently used as climate input for mGROWA model simulation. Evaluation of the interpolation schemes showed that the application of Regression Kriging and Linear Regression led to an acceptable interpolation result for reference evapotranspiration, especially in case the FAO Penman-Monteith equation was used. On the other hand, Regression Kriging also provided a more convincing interpolated result for precipitation. Meanwhile, mGROWA simulation results were affected by climate input data sets generated by applying difference interpolation schemes. Therefore, it is essential to select an appropriate interpolation scheme, in order to generate a convincing climate input.}, language = {en} } @inproceedings{SchleyMolkenthinMejstrik, author = {Schley, Frank and Molkenthin, Frank and Mejstrik, M.}, title = {Netzbasiertes Kollaborationsmodell im Spezialtiefbau - Virtuelle Baubude -}, series = {Junge Wissenschaftler forschen, 13. Forum Bauinformatik, M{\"u}nchen 2001}, booktitle = {Junge Wissenschaftler forschen, 13. Forum Bauinformatik, M{\"u}nchen 2001}, publisher = {VDI-Verlag}, address = {D{\"u}sseldorf}, isbn = {3-18-316904-5}, pages = {70 -- 77}, language = {de} } @misc{HeWendlandMolkenthin, author = {He, Qianwen and Wendland, Frank and Molkenthin, Frank}, title = {The analysis of nitrogen load and simulation uncertainty using SWAT in a catchment with paddy field in China}, series = {Water Science \& Technology Journal}, volume = {80}, journal = {Water Science \& Technology Journal}, number = {4}, issn = {0273-1223}, doi = {10.2166/wst.2019.326}, pages = {806 -- 816}, language = {en} } @inproceedings{MolkenthinHolz, author = {Molkenthin, Frank and Holz, Klaus-Peter}, title = {Generalised Information Systems for Physical State Variables in Hydroscience}, series = {Water engineering for the future, Vol. 1., Abstracts of XXXI IAHR Congress, Coex, Seoul, September 11 - 16, 2005}, booktitle = {Water engineering for the future, Vol. 1., Abstracts of XXXI IAHR Congress, Coex, Seoul, September 11 - 16, 2005}, editor = {Jun, Byong-Ho}, publisher = {Korea Water Resources Association}, address = {Seoul}, isbn = {89-87898-25-3}, pages = {S. 107}, language = {en} } @inproceedings{HolzHildebrandtMolkenthin, author = {Holz, Klaus-Peter and Hildebrandt, Gerald and Molkenthin, Frank}, title = {Virtual Laboratories for Projects in Environment Water}, series = {The information society and enlargement of the European Union, 17th International Conference Informatics for Environment Protection, Cottbus 2003}, booktitle = {The information society and enlargement of the European Union, 17th International Conference Informatics for Environment Protection, Cottbus 2003}, editor = {Gnauck, Albrecht}, publisher = {Metropolis-Verlag}, address = {Marburg}, isbn = {3-89518-440-3}, abstract = {Modern information and communication technology (ICT) enables new technical solutions to support collaboration in environmental engineering over distance. The establishment of "virtual laboratories" including application of Internet based project platforms, distributed team work and collaboration methods require new kinds of soft skills, knowledge and experience and a new "technological culture" to be generated just by doing - a task for education, training and profession in Hydro-Informatics. This is a challenge for the European dimension, where in future experts and engineers from different countries with different languages, different mentalities as well as different specialization and professional experience have to collaborate in research, teaching and practice. Training of collaborating in such new environment is the challenge of the courses HydroWeb and HydroEurope which by collaboration of 23 universities world-wide will help to establish common high quality university teaching courses and establish links between students from the involved countries. The students are solving a given environmental engineering task in distributed teams in the Internet. The students acquired in this course experience in interdisciplinary team work, net based project co-ordination and Web based reporting. They strengthened their social competence to collaborate in heterogeneous teams with members of different habits, nationalities, ages, educational backgrounds. The described experiment might be the basis to introduce Web based collaborative engineering in the regular course programme of water-environment related curricula at universities.}, language = {en} } @misc{FrimpongMolkenthin, author = {Frimpong, Bernard Fosu and Molkenthin, Frank}, title = {Tracking Urban Expansion Using Random Forests for theClassification of Landsat Imagery (1986-2015) and PredictingUrban/Built-Up Areas for 2025: A Study of the KumasiMetropolis, Ghana}, series = {Land}, volume = {10}, journal = {Land}, number = {1}, issn = {2073-445X}, doi = {10.3390/land10010044}, pages = {1 -- 21}, abstract = {Kumasi is a nodal city and functions as the administrative and economic capital of the Ashanti region in Ghana. Rapid urbanization has been experienced inducing the transformation of various Land Use Land Cover (LULC) types into urban/built-up areas in Kumasi. This paper aims at tracking spatio-temporal LULC changes utilizing Landsat imagery from 1986, 2013 and 2015 of Kumasi. The unique contribution of this research is its focus on urban expansion analysis and the utilization of Random Forest (RF) Classifier for satellite image classification. Change detection, urban land modelling and urban expansion in the sub-metropolitan zones, buffers, density decay curve and correlation analysis were methodologies adopted for our study. The classifier yielded better accuracy compared to earlier works in Ghana. The evaluation of LULC changes indicated that urban/built-up areas are continually increasing at the expense of agricultural and forestlands. The urban/built-up areas occupied 4622.49 hectares (ha) (23.78\%), 13,447.50 ha (69.18\%) and 14,004.60 ha (72.05\%) in 1986, 2013 and 2015, respectively of the 19,438 ha area of Kumasi. Projection indicated that urban/built-up areas will occupy 15,490 ha (79.70\%) in 2025. The urban expansion was statistically significant. The results revealed the importance of spatial modeling for environmental management and city planning.}, language = {en} } @misc{HeMolkenthin, author = {He, Qianwen and Molkenthin, Frank}, title = {Improving the integrated hydrological simulation on a data-scarce catchment with multi-objective calibration}, series = {Journal of Hydroinformatics}, volume = {23}, journal = {Journal of Hydroinformatics}, number = {2}, issn = {1464-7141}, doi = {10.2166/hydro.2021.132}, pages = {267 -- 283}, abstract = {The process-based hydrological model Soil and Water Assessment Tool ensures the simulation's reliability by calibration. Compared to the commonly applied single-objective calibration, multi-objective calibration benefits the spatial parameterization and the simulation of specific processes. However, the requirements of additional observations and the practical procedure are among the reasons to prevent the wider application of the multi-objective calibration. This study proposes to consider three groups of objectives for the calibration: multisite, multi-objective function, and multi-metric. For the study catchment with limited observations like the Yuan River Catchment (YRC) in China, the three groups corresponded to discharge from three hydrometric stations, both Nash-Sutcliffe efficiency (NSE) and inversed NSE for discharge evaluation, and MODIS global terrestrial evapotranspiration product and baseflow filtered from discharge as metrics, respectively. The applicability of two multi-objective calibration approaches, the Euclidean distance and nondominated sorting genetic algorithm II, was analyzed to calibrate the above-mentioned objectives for the YRC. Results show that multi-objective calibration has simultaneously ensured the model's better performance in terms of the spatial parameterization, the magnitude of the output time series, and the water balance components, and it also reduces the parameter and prediction uncertainty. The study thus leads to a generalized, recommended procedure for catchments with data scarcity to perform the multi-objective calibration.}, language = {en} } @misc{TrinhMolkenthin, author = {Trinh, Manh Xuan and Molkenthin, Frank}, title = {Flood hazard mapping for data-scarce and ungauged coastal river basins using advanced hydrodynamic models, high temporal-spatial resolution remote sensing precipitation data, and satellite imageries}, series = {Natural Hazards}, volume = {109}, journal = {Natural Hazards}, number = {1}, issn = {0921-030X}, doi = {10.1007/s11069-021-04843-1}, pages = {441 -- 469}, abstract = {This paper presents an integrated approach to simulate flooding and inundation for small- and medium-sized coastal river basins where measured data are not available or scarce. By coupling the rainfall-runoff model, the one-dimensional and two-dimensional models, and the integration of these with global tide model, satellite precipitation products, and synthetic aperture radar imageries, a comprehensive flood modeling system for Tra Bong river basin selected as a case study was set up and operated. Particularly, in this study, the lumped conceptual model was transformed into the semi-distributed model to increase the parameter sets of donor basins for applying the physical similarity approach. The temporal downscaling technique was applied to disaggregate daily rainfall data using satellite-based precipitation products. To select an appropriate satellite-derived rainfall product, two high temporal-spatial resolution products (0.1 × 0.1 degrees and 1 h) including GSMaP_GNRT6 and CMORPH_CRT were examined at 1-day and 1-h resolutions by comparing with ground-measured rainfall. The CMORPH_CRT product showed better performance in terms of statistical errors such as Correlation Coefficient, Probability of Detection, False Alarm Ratio, and Critical Success Index. Land cover/land use, flood extent, and flood depths derived from Sentinel-1A imageries and a digital elevation model were employed to determine the surface roughness and validate the flood modeling. The results obtained from the modeling system were found to be in good agreement with collected data in terms of NSE (0.3-0.8), RMSE (0.19-0.94), RPE (- 213 to 0.7\%), F1 (0.55), and F2 (0.37). Subsequently, various scenarios of flood frequency with 10-, 20-, 50-, and 100-year return periods under the probability analysis of extreme values were developed to create the flood hazard maps for the study area. The flood hazards were then investigated based on the flood intensity classification of depth, duration, and velocity. These hazard maps are significantly important for flood hazard assessments or flood risk assessments. This study demonstrated that applying advanced hydrodynamic models on computing flood inundation and flood hazard analysis in data-scarce and ungauged coastal river basins is completely feasible. This study provides an approach that can be used also for other ungauged river basins to better understand flooding and inundation through flood hazard mapping.}, language = {en} } @misc{GourbesvilleGomezValentinMolkenthinetal., author = {Gourbesville, Philippe and Gomez Valentin, Manuel and Molkenthin, Frank and Hewett, Caspar and Sinicyn, Grzegorz and Griensven, Ann van}, title = {HydroEurope—WaterEurope: 20 years of Practice in Collaborative Engineering for Hydroinformatics}, series = {Advances in Hydroinformatics : Models for Complex and Global Water Issues—Practices and Expectations Springer Water}, journal = {Advances in Hydroinformatics : Models for Complex and Global Water Issues—Practices and Expectations Springer Water}, editor = {Gourbesville, Philippe and Caignaert, Guy}, publisher = {Springer}, address = {Singapore}, isbn = {978-981-19-1600-7}, doi = {10.1007/978-981-19-1600-7_80}, pages = {1255 -- 1280}, abstract = {Since 2000 and under the various Erasmus and Erasmus + frameworks of the European Commission, 6 European universities have initiated an ve innovatiintensive training program dedicated to hydroinformatics and supported by the data of the Var catchment, France. Over the two decades, the HydroEurope/WaterEurope course has welcome more than 2000 M.Sc students with the ambition to equip them with the competences and skills related to hydrological analyst, flood modeling, damage assessment and engineering design with the most advanced simulation tools. The concept of collaborative engineering associated to a project based pedagogic approach has been used to develop teamwork distributed over time—almost 3 months—and space with team members located in the different European participating institutions. The activities are built around the Var catchment that is regularly affected by Mediterranean flood events associated to major damages. The various teams have to elaborate within a holistic approach, mitigation actions. Since the origins, the program has been integrated within the master degree curriculum of each participating institution and academic recognition has been achieved through credits (ECTS). Industrial actors from the hydroinformatic field have been associated to the program since the early stage and have provided support with expert staff and simulation tools that are today offered through a modelling platform. The 20 years of development have underlined the efficiency of the pedagogic approach and have contributed to equip the new generation of water professionals with new concepts and methods for a better water management.}, language = {en} } @inproceedings{TrinhNguyenMolkenthin, author = {Trinh, Manh Xuan and Nguyen, Mai Dang and Molkenthin, Frank}, title = {Flood risk assessment in the Tra Bong river catchment, Vietnam}, series = {International Symposium on Lowland Technology (ISLT 2018), Hanoi, Vietnam}, booktitle = {International Symposium on Lowland Technology (ISLT 2018), Hanoi, Vietnam}, publisher = {Construction Publishing House}, address = {Hanoi}, isbn = {978-604-82-2483-7}, pages = {8}, abstract = {Extreme flood events often cause tremendous damage and enormous risks to our life and nature. Flooding is one of the most costly kinds of natural disasters in Vietnam. Tra Bong is a river catchment located in Quang Ngai province, Vietnam. Due to the effect of typhoons originated from the East Sea, many extreme floods occur in this river annually. Therefore, considering the impacts of flooding and flood risk assessment in this river plays an important role in mitigating and adapting to flood risk. In this paper, a hydrological model (MIKE NAM) and some hydro-dynamic models such as the MIKE 11 HD, MIKE 21 FM and MIKE Flood models were applied as the effective tools to simulate flooding and inundation in the downstream area of the catchment. Two flood risk maps for 2009 and 100 year return period were created based on the intersection of hazard and vulnerability maps which were obtained from flood maps, land-use and population density. Accordingly, more than 80\% of total flooded area is at high and very high risk. Almost 35 km2 of the flooded area were under high and very high risk in the year 2009, while, approximately 45.5 km2 would be under high and very high risk in the design flood event of 100 year return period.}, language = {en} }