Mapping Future Canadian Arctic Coastlines

Abstract: The Canadian Arctic currently faces changing coastlines due isostatic rebound and climate change-driven sea-levels rising. This thesis seeks to answer how local coastlines will change over time under different Representative Concentration Pathway (RCP) scenarios, where errors in modelled coastlines come from, and how much of an impact isostatic rebound has on sea-levels compared to climate-change driven changes. Maps which show changes in coastline through predicted sea-level changes in 2035, 2065, and 2100 have been produced through ArcGIS Pro’s Forest-based regressions tool, with training data from historical climate variables and projection data under CMIP5 for RCP 2.6, 4.5, and 8.5, where RCP 2.6 refers to a low emissions scenario, RCP 4.5 refers to a moderate emissions scenario, and RCP 8.5 refers to a high emissions scenario. Isostatic rebound data can be sourced and run through the ICE-4G model. Multiple models were examined to ascertain which climate variables are needed to produce a stable model, using training data prior to and including 2000 and testing data post 2000 from 9 spatially diverse locations in the Canadian Arctic. These results suggest that for Cambridge Bay, Resolute, and Alert, there will be little change in coastline under any RCP scenario. However, for Tuktoyaktuk coastlines are projected to advance significantly. While 9 locations total were used in during the process, only 4 were examined in greater detail due to data and time constraints. These finding should be considered when making plans for future coastal infrastructure.