The Canadian Prairies are no stranger to weather extremes and natural disasters. Floods and droughts here are among the costliest natural disasters in Canada, causing billions of dollars in damages to infrastructure and industries such as agriculture. These events are becoming more frequent and widespread as our atmosphere changes due to increased inputs of carbon dioxide and other greenhouse gases since the industrial revolution in the 1800s. Since the turn of the 21st century, the region has experienced some of the most devastating extreme events in its history, setting records in terms of damage, costs, severity/intensity, and spatial extent. Conditions have also oscillated between opposing extremes of flood and drought in a very short period of time and in close geographical proximity or at the same locations. These recent extreme events have been unprecedented in over a century of observations – a record-breaking summer flood devastated the Assiniboine River Basin (ARB) in 2014 while a severe, widespread drought impacted large areas across Western Canada in 2015. Both events cost billions in damages and highly impacted agricultural producers. Events such as these are occurring against a backdrop of rapidly changing environmental conditions, indicating that extreme flood and drought events will be more frequent and severe.
Given the rapid environmental change the Canadian Prairies are experiencing, our historical understanding of water patterns and flows are no longer applicable to the future, let alone the current state of the region. Improving our understanding of the factors that contributed to the recent extreme flood and drought events can provide insight into the water futures for the Canadian Prairies. The following provides a brief overview of the 2014 ARB flood and 2015 drought and gives insight into what may be expected in the future on the Canadian Prairies.
The world is entering an era of immense water-related threats. Flood and drought directly threaten both people and industry. Floods kill, but also destroy farms and farmland and disrupt agricultural production; droughts threaten agricultural production and the viability of farms and rural communities. The loss of water through drought caused more than $6B in economic damage to the Prairie Provinces in 2001-2002. More generally the value of water to the Canadian economy is estimated at between $7.8B and $22.9B per year in 2011 dollars. We need to protect farmers and food producers against extreme water threats in the face of climate uncertainty and human-induced global change. Canada and much of the world are ill-prepared for this new era of water threats, which has already resulted in intensified floods and droughts, reduced water availability and degraded water quality, costing billions in economic loss and impacting the health of populations.
Why is this and how serious is the problem? Climate warming and human actions are altering precipitation patterns, reducing snowpacks, accelerating glacier melt, intensifying floods, and increasing the risk of droughts, while pollution from population growth and industrialization is degrading water systems. By 2050, six billion people could face water scarcity. Nearly 80 per cent of the world’s jobs depend upon having access to an adequate supply of water and water-related services and many of these are in agriculture. Global trade in food and goods, as well as entire communities, industries and nations are at risk. With such unprecedented change, it is clear that the historical patterns of water availability are no longer a reliable guide for the future, and few Canadian industries will feel this as acutely as will agriculture. Adaptation to these water changes will require new science to understand the changing climate, land, agricultural systems, water and their interactions; new computer modeling tools that will precisely capture these interconnected forces and their societal implications; new monitoring systems with greater capacity to warn of critical environmental changes; and more effective mechanisms to translate new scientific knowledge into farm management. This translates into the grand challenge for water science in Canada and globally: “How can we best prepare for and manage water futures in the face of dramatically increasing risks?”