Simulated canola yield responses to climate change and adaptation in Canada

Abstract

A projected future warmer climate implies significant impacts on canola (Brassica napus L.) production in Canada. We aimed to use a modeling approach to simulate climate change impacts on canola yield in Canada and to evaluate potential adaptation measures. The CSM-CROPGRO-Canola model was used to simulate the responses of canola to the projected climate change at Brandon on the Prairies, and West Nipissing and Normandin in eastern Canada. Future climate scenarios for the near (2041–2070) and distant (2071–2100) future under two representative concentration pathways (RCP4.5 and RCP8.5) were developed based on climate change simulations by a regional climate model CanRCM4. Seeding dates were estimated from air temperature, precipitation, and soil moisture to account for the potential of earlier seeding as an adaptation measure. Compared to the baseline climate, simulated seed yield reduction was 42, 21, and 24% in the near future and of 37, 27, and 23% in the distant future, under RCP4.5, respectively for Brandon, West Nipissing, and Normandin. A larger reduction was simulated under RCP8.5, especially in the distant future at Brandon and West Nipissing. The simulated seed yield reduction was associated with increases in heat and water stresses under rainfed conditions with current N fertilizer application rates. Coping with heat and water stresses is a big challenge for canola production in Canada under the projected climate change, especially on the Canadian Prairies.