In this study, 17 hydrologists with different experience in hydrological modelling applied the same conceptual catchment model (HBV) to a Greek catchment, using identical data and model code. Calibration was performed manually. Subsequently, the modellers were asked for their experience, their calibration strategy, and whether they enjoyed the exercise. The exercise revealed that there is considerable modellers’ uncertainty even among the experienced modellers. It seemed to be equally important whether the modellers followed a good calibration strategy, and whether they enjoyed modelling. The exercise confirmed previous studies about the benefit of model ensembles: Different combinations of the simulation results (median, mean) outperformed the individual model simulations, while filtering the simulations even improved the quality of the model ensembles. Modellers’ experience, decisions, and attitude, therefore, have an impact on the hydrological model application and should be considered as part of hydrological modelling uncertainty.

This article addresses the sustainability implications of post-disaster measures in the context of the 2004 Indian Ocean Tsunami by presenting an analysis of the current situations and changes in some of the affected regions. Sustainability implications of measures are captured by investigating the persistence of the social and economic living conditions in relation to post-disaster measures, and the alignment of the measures with basic environmental aspects. Based on major concepts relevant in disaster science and sustainability research, the study explored sustainability aspects of post-disaster measures implemented after the 2004 tsunami, by conducting selected interviews among the participants of the 2015 international seminar ''11 Years after the Indian Ocean Tsunami 2004'' and a broader online survey. Information was sought about (1) the current state of vulnerability of the local population in the regions affected; (2) the main lessons that have been identified to improve project design and management of recovery and vulnerability reduction; and (3) project sustainability implications with respect to the state of today's vulnerability. Based on the analysis of the information on these three priority areas, selected tasks for future disaster risk management are identified, such as more integrative planning and improved coordination with international organizations and local people.

When discussion of risks takes place, whether in political debates or in scientific discourses, flood-related hazards are among the most frequently mentioned events in many world regions. Scientific explanations of the risk present in any geographical region are generally based on the hydro-physical process of flooding, and the specific vulnerabilities of the local population in respect of this process. This paper follows a different pathway, arguing that this perspective is limited in explaining the existence of specific patterns of socio-spatial activity which lead to inequalities in flood risk management. Using social practice theory and applying the concept of riskscapes allows for a more differentiated perspective on the presence and evolution of risks in spatial entities. By using the specific conceptual delineation of social practices elaborated by social theorist Theodore Schatzki the focus is put on materially and spatially relevant performances that are involved in social constructions of risk. Moreover, a specific empirical method of in-depth research into socially and spatially relevant practices is presented. This visual geographic approach, developed in empirical research in Mexico as part of a recently finalised dissertation project, involves a participatory photography workshop as a method to trigger reflection on social practices, and analyses the photographs produced in order to identify relevant material aspects of social practices relating to flood management. The empirical findings present specific social flood management practices along the river Usumacinta in Chiapas. It is shown that participatory visual methods contribute to the identification of relevant social dynamics of flood management, and that they allow in-depth analysis of the interlinkages between different social practices, identifying synergies and conflicts between practices related to flood management. The tool developed based on the riskscapes concept is promoted here as a relevant step towards more thorough analysis of social practices, with the aim of identifying politically relevant inequalities in processes of flood management in the south of Mexico, and hopefully beyond. Zusammenfassung: In politischen Debatten sowie wissenschaftlichen Diskursen zum Thema Risiko gehören weltweit Hochwasserereignisse zu den am häufigsten angeführten Beispielen. Dabei machen hydro-physische Prozesse von Hochwasser und spezifische Vulnerabilitäten von Bevölkerungsgruppen einen Großteil der wissenschaftlichen Erklärungsansätze für Risiko in geographischen Regionen aus. Dieser Beitrag verfolgt einen anderen Erklärungsweg und zeigt auf, dass solche Ansätze insofern begrenzt sind, dass sie vorhandene sozialräumliche Aktivitäten, die zu Ungleichheiten im Hochwasserrisikomanagement führen, nur unzureichend berücksichtigen. Eine explizite Bezugnahme auf Praxistheorie und die Anwendung des Riskscapes-Konzeptes verspricht einen differenzierten Blick auf die Präsenz und Entwicklung von Risiken in geographischen Räumen. Dieser Artikel bezieht sich a...

In the response of the flood disaster in Germany 2021 a vast number of spontaneous volunteers (SVs) participated. They organized coordinating services, developed emergent forms of SVs and thus hold the potential to improve existing flood managing capacities. This raises the need for in‐depth knowledge about SVs and organization, the use of information and communication technologies (ICT), social and individual aspects. This article analyzed results of an online survey (n = 2636) with the aim to discuss challenges and potentials to develop SVs as social innovations in flood risk management. As a result, SVs are strong value‐based motivated, can be psychologically stressed and travel long distances, especially when they got aware of helping possibilities via social media. Disaster relief organizations rarely cooperate with or integrate SVs, but when they collaborate, SVs' satisfaction with authorities increases significantly. Based on the results, this article derives preplanning of useful concepts consider safety aspects, ICT utilization, foster mutual respect between SVs and authorities and supporting sense of community as key results for development of social innovations. Especially in light of pandemics, social crisis like refugee movements, and climate change‐related disasters, the requirement rises for engaging SVs.