Hydrological Extremes

Event Information Floods and drought are the major weather related hydrological disasters and recent events have demonstrated Europe’s continuing exposure to these natural hazards. 'High and low flows and associated floods and droughts are natural phenomena caused by meteorological anomalies and modified by the physical characteristics of catchments. The knowledge about the quantity, timing and risk of extreme discharges during floods and droughts is the basic requirement for a broad range of purposes in hydrology and water resources management. This knowledge has ideally to be based on the understanding the controls of the genesis of hydrological extremes (like the importance of landscape heterogeneities, threshold processes, scaling issues), finding appropriate ways how to characterize them (spatial and temporal variability, regional patterns) and designing reliable methods of predicting. The main objectives of this session are (a) to foster the understanding of the main governing processes of hydrological extremes, including spatial and temporal patterns of floods and droughts, (b) to discuss modeling approaches and concepts how to include process understanding in predictive models, (c) to shed light on the regional characteristics and spatial patterns of floods and droughts and the processes that give rise to such patterns including climate forcing, extreme precipitation and catchment response, (d) to present methods and practical applications for estimating and/or predicting floods, droughts and low flows at a regional scale as well as regional methods for making predictions at the local scale, (e) to address the potential impact of global change, including climate and land use changes, on hydrological extremes, (f) to profit from the similarity and differences of modeling concepts for both extremes. Specifically, papers are solicited that address one or more of the following questions: * what are the important mechanisms producing regional hydrological extremes, and how the use of diverse hydrological methods can contribute to highlighting the governing processes * what is the role of climatic forcing and catchment properties in the regional distribution of hydrological extremes, * which hydro-meteorological and catchment characteristics and indices can be used to describe regional patterns of hydrological extremes, * how do anthropogenic impacts and different land use patterns affect the spatial patterns of regional hydrological extremes, * how effective and reliable are the statistical techniques (e.g., cluster analysis, artificial neural networks, copulas, Fourier analysis, etc.) for identification of watersheds with similar dominant hydrological characteristics. The scope of the session includes both general methodological contributions and case studies of hydrological extremes in different regions. All methodological contributions will ideally discuss the benefits of the method for the challenges of hydrological extremes. Preliminary List of Solicited Speakers Ross Woods, NIWA, Christchurch, New Zealand Murugesu Sivapalan, University of Illinois General Statement The information contained hereafter has been compiled and uploaded by the Session Organizers via the "Organizer Session Form". The Session Organizers have therefore the sole responsibility that this information is true and accurate at the date of publication, and the conference organizer cannot accept any legal responsibility for any errors or omissions that may be made, and he makes no warranty, expressed or implied, with regard to the material published