Regions in northern latitudes are likely to be strongly affected by climate change with shifts in weatherthat may be conducive to increased agricultural productivity. In this study the DNDC model was used toassess the effect of climate change on crop production and GHG emissions at long-term experimentalsites in Canada. Crop production in the model was parameterized using measured data, and then sim-ulations were performed using historical weather (1961–1990) and future IPCC SRES climate scenarios(2040–2069). The DNDC model predicted that for western Canada under the SRES scenarios and no changein cultivar, yields of spring wheat would increase by 37% and winter wheat by 70%. Corn responded favor-ably to an increase in heat units at the eastern site with a 60% increase in yields. At all locations, yieldswere projected to increase further when new cultivars with higher GDD requirements were assumed.These increases were notable considering that the estimated soil water deficit indices indicated that therecould be less water available for crop growth in the future. However, when accounting for increased wateruse efficiency under elevated CO2, DNDC predicted less crop water stress. Nitrous oxide emissions perton of wheat were projected to increase across most of western Canada by about 60% on average for theA1b and A2 SRES scenarios and by about 30% for the B1 scenario. Nitrous oxide emissions per unit areawere predicted to increase under corn production at the eastern location but to remain stable per tonof grain. Model results indicated that climate change in Canada will favor increased crop production butthis may be accompanied by an increase in net GHG emissions for small grain production.