Modelling the long term impact of climate change on the carbon budget of Lake Simcoe, Ontario using INCA-C

► Despite their shortcomings, process-based model can be used to make useful conclusions about possible future conditions. ► Climate change scenarios suggest a monotonic increase in DOC concentration in surface waters draining into Lake Simcoe. ► Climate change may cause shifts in seasonality of DOC, with higher concentrations expected in the autumn and winter. ► Warmer temperatures may enhance mineralization of riverine DOC, suggesting a future increase in CO2 emission from rivers.