Review of climate change projections for southern Manitoba and potential impacts for agriculture
Danny Blair, University of Winnipeg, Winnipeg, MB, R3B 2G3; Ainsley Little, Agri-Environment Knowledge Centre, Carman, MB R0G 0J0; Matthew Wiens, Agri-Environment Knowledge Centre, Beausejour, MB, R0E 0C0

Recent work by Canadian and international climate researchers suggest that significant climatic changes for southern Manitoba will occur by the middle of this century. Temperature trends indicate an increase in average yearly temperatures which will be accompanied by increased variability. The most prominent increases will be observed over the winter months and in daily minimum temperatures resulting in decreased diurnal variation. We should also anticipate fewer cold winters in general. Over the summer months heat waves are expected to occur more often. With the above mentioned changes we can predict an increase in growing-degree days and a longer frost-free season. Precipitation dynamics are also projected to change. Winter precipitation will likely increase; however, more of this precipitation will fall as rain than what is currently observed. The occurrence of very wet winters may increase. Intense rain events will likely become more frequent, but drought is also expected to become more common and more severe. The impacts of these climate changes for agriculture in Manitoba will likely be both positive and negative; however, more negative than positive impacts are expected. Positive impacts include opportunities for longer-season crops, decreased heating costs, a longer grazing season, and less winter stress for livestock. Expected negative impacts include new weed, insect and disease challenges, increased cooling costs, more flooding, more heat and water stress for crops and animals, greater risk of drought, and increased vulnerability of soil to erosion.