Climate-driven trends in the occurrence of major floods across North America and Europe

• Main Authors: Hodgkins, G.A, Whitfield, P.H., Burn, D.H., Hannaford, J., Renard, Benjamin, Stahl, Konrad, Fleig, A.K., Madsen, H., Mediero, L., Korhonen, J., Murphy, Craig, Crochet, Pierre-André, Wilson, D.
• Other Authors: US GEOLOGICAL SURVEY AUGUSTA USA, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), ENVIRONMENT CANADA VANCOUVER CAN, UNIVERSITY OF WATERLOO ONTARIO CAN, CENTRE FOR ECOLOGY AND HYDROLOGY WALLINGFORD GBR, Hydrologie-Hydraulique (UR HHLY), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), UNIVERSITY OF FREIBURG DEU, NORWEGIAN WATER RESOURCES AND ENERGY DIRECTORATE OSLO NOR, DHI HORSHOLM DNK, TECHNICAL UNIVERSITY OF MADRID ESP, FINNISH ENVIRONMENT INSTITUTE HELSINKI FIN, NATIONAL UNIVERSITY OF IRELAND MAYNOOTH IRL, ICELANDIC METEOROLOGICAL OFFICE REYKJAVIK ISL
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2016
• Subjects: AMERIQUE DU NORD; EUROPE; [SDE]Environmental Sciences; Canada; Norway; Iceland
• Online Access: https://hal.inrae.fr/hal-02605307

International audience Every year river floods cause enormous damage around the world. Recent major floods in North America and Europe, for example, have received much press, with some concluding that these floods are more frequent in recent years as a result of anthropogenic warming. There has been considerable scientific effort invested in establishing whether observed flood records show evidence of trends or variability in flood frequency, and to determine whether these patterns can be linked to climatic changes. However, the river catchments used in many published studies are influenced by direct human alteration such as reservoir regulation and urbanisation, which can confound the interpretation of climate-driven variability. Furthermore, a majority of previous studies have analysed changes in low magnitude floods, such as the annual peak flow, at a national scale. Few studies are known that have analysed changes in large floods (greater than 25-year floods) on a continental scale. To fill this research gap, we present a study analysing flood flows from reference hydrologic networks (RHNs) or RHN-like gauges across a large study domain embracing North America and much of Europe. RHNs comprise gauging stations with minimally disturbed catchment conditions, which have a near-natural flow regime and provide good quality data; RHN analyses thus allow hydro-climatic variability to be distinguished from direct artificial disturbances or data inhomogeneities. One of the key innovations in this study is the definition of an RHN-like network consisting of 1204 catchments on a continental scale. The network incorporates existing, well-established RHNs in Canada, the US, the UK, Ireland and Norway, alongside RHN-like catchments from Europe (France, Switzerland, Iceland, Denmark, Sweden, Finland, Spain), which have been incorporated in the network following a major effort to ensure RHN-like status of candidate gauges through consultation with local experts. As the aim of the study is to examine long-term variability ...