A 1300 year reconstruction of paleofloods using oxbow lake sediments in temperate southwestern Québec, Canada

The study of paleofloods provides important information on past flood frequency and intensity for regions where there is a paucity of records, it therefore extends our knowledge of flood occurrence beyond the historical record. Many paleoflood reconstructions come from the arid dry climate of southwestern USA and from Europe with few studies being conducted in temperate climates of North America. This study uses sediment cores from oxbow lakes to reconstruct past flood events in a temperate region. Cores extracted from two oxbow lakes along the Désert River in southwestern Québec, Canada were analyzed for magnetic susceptibility, loss-on-ignition, grain-size and were radiocarbon dated (14C). Using a combination of magnetic susceptibility variations, along with changes in grain-size and organic material content, 5 floods were identified within the 220 cm core (1300 years) from the North oxbow lake, and six floods in the 118 cm core (600 years) from the South oxbow lake. This study provides evidence to support the use of oxbow lakes in temperate regions as a proxy of past floods, thus helping us understand hydroclimatic changes at regional scales. Data that spans a longer period of time and in different environments is key to increase flood modelling accuracy to improve mitigation strategies under a changing climate.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author