FLOODPLAIN MAPPING OVER CANADA - (performance at inundation level; population exposure; climate change impacts) - Slobodan P. Simonović

Simonović Fellow Royal Society of Canada Fellow Canadian Academy of Engineering FCSCE, FASCE, FIWRA Director of Engineering Studies, ICLR Professor Emeritus, Western University 2|PRESENTATIONOutline ▪ Introduction ▪ Floodplain mapping ▪ Methodology ▪ Use of reanalysis data ▪ Use of CaMa-Flood hydrodynamic model ▪ Population flood exposure assessment ▪ Use of global population datasets ▪ Investigat. [...] Bogdana Sredojevic 4|INTRODUCTIONProject justification 5|INTRODUCTIONProject objectives ▪ Development of the methodology for high resolution flood inundation analyses over large regions ▪ Investigation of the fidelity of four reanalysis runoff products ▪ Investigation of the utility of four global population datasets for population flood exposure assessment ▪ Investigation of the changes in floodp. [...] 18| ▪ Population flood exposure assessment 19|METHODOLOGYPopulation exposure assessment ▪ Two sets of floodplain maps: all categories of flood depth (>0 m) and only high and very high flood depths (>1.5 m) ▪ Census population dataset 2006- 2019 ▪ Global population datasets 2015 20|DATAPopulation exposure assessment Aggregated population at various census divisions in 2015 as observed with (a) Stat. [...] 26.|RESULTSPopulation exposure assessment 27|CONCLUSIONSPopulation exposure ▪ Global population datasets can be used for population flood exposure assessment ▪ WorldPop and LandScan provide the closest estimates to the census data across Canada ▪ Most of the high and very-high exposed divisions are located in the southern and western provinces of Ontario, Alberta, and British Columbia. [...] 39|CONCLUSIONSClimate change ▪ First time use of the latest CMIP6 project for understanding the changes in floodplain regimes in the future over a large country ▪ The near-and far-future 1 in 100-yr and 1 in 200-yr flood events will add to a rise in the high-, and very-high flood hazards ▪ Flood frequencies in the far future will increase in several regions (in the western, and northern parts and.