Warmer winters will freeze crops

In the latest edition of Agronomy Journal, scientists from Agriculture and Agri-Food Canada report that some crops, such as perennial forage crops grown in parts of North America, will be at greater risk as the climate warms. The report, based on agro-climatic indices calculated up to 2069, shows that loss of snow cover due to warmer winter conditions will increase exposure of plants to freezing temperatures, leading to ice damage.

The study, using data from 69 climatic stations across Eastern Canada, also predict that warmer autumns will mean crops do not develop sufficient cold hardiness before winter arrives. Survival of perennial crops over the winter months requires the right climatic conditions. Sub-freezing temperature, loss of cold hardiness, ice encasement, and soil heaving can all result in crop losses. Winter temperatures are expected to increase by 2 to 6°C over the next 50 years in Eastern Canada.

Gilles Bélanger, leader of the study, said, “This might be a surprise to many that warmer winter conditions will mean greater risks to perennial forage crops. Such crops in Canada and in the northern part of the United States prefer the comfort of a nice snow cover after a good rest period in the fall. Rain, ice, and no snow cover in the middle of the winter will occur more often in the future; this brings no comfort to perennial forage crops.” Nevertheless, the scientists remain confident that current and future research efforts in crop management practices will help producers make the best of climate change.