There is little doubt that increasing atmospheric concentrations of greenhouse gases will generally cause the Earth to warm and alter precipitation patterns in various parts of the globe. Changes in precipitation and temperature will thereby impact hydrological systems, and the global warming alarmists love to show images of floods or dried-up streams to make the threat of the anthropogenic greenhouse effect look as bad as possible. Indeed, the global warming scare has deep roots in the drought of 1988 over the southeastern United States that created an anomalous low flow on the Mississippi River (recall headlines about the Mississippi River drying up?). If you have forgotten, the summer of 1988 also gave us the huge wildfires of the West (Yellowstone Park burned in that summer and fall) as well as Hurricane Gilbert, and those images of how global warming will impact us have lived on powerfully ever since.
The literature on how the enhanced greenhouse effect will alter streams and rivers shows us everything from floods to record-breaking low flows, and of course, both will be bad for humans and natural ecosystems. Floods are definitely bad, but in low flow situations, agriculture will be severely impacted, direct human use of water would need to be curtailed, and if the stream provides hydropower, the impacts can be severe in the energy sector.
Canada is a mid-to-high latitude, northern hemispheric land mass where global warming is expected to be far greater than in other parts of the world, and this warming will surely be felt by the streams across their country. An article has appeared in a recent issue of Journal of Hydrology entitled “Streamflow in the Winnipeg River Basin, Canada: Trends, Extremes and Climate Linkages” by Scott St. George of the Geological Survey of Canada and the University of Arizona. The final sentence of the abstract caught our eye as he wrote “the potential threats to water supply faced by the Canadian Prairie provinces over the next few decades will not include decreasing streamflow in the Winnipeg River basin.” We knew immediately that we had a Winnipeg winner on the line! Let the world know that funding for his work was provided by Manitoba Hydro, the Manitoba Geological Survey, the Prairie Adaptation Research Collaborative and the Natural Sciences and Engineering Research Council of Canada.