Ask an Ecology Expert: How does the Climate Crisis affect our Seasons?

OThe past few decades, climate change has been driving what scientists refer to as “season creep” in some parts of the world: winters are getting shorter, spring is coming earlier, and summers are longer and hotter.¹These changes to the seasons not only disrupt human life but also have a profound effect upon animals. We asked Madhur Anand, a professor of ecology at the University of Guelph’s school of environmental sciences, what rising temperatures mean for our ecosystems.

Over the last year, Canada experienced a lot of extreme weather, including deadly heat waves, a brutal wildfire ­season, and flooding in BC. These extreme weather events are they related to climate change?

The temperature is the most obvious thing when people think of climate change. But precipitation is also an important variable. Those two factors largely explain the current vegetation patterns in Canada—the temperate rainforest in BC, the grasslands in the Prairies, the tundra in the Arctic, and the boreal forest spread across most of the country. Rising temperatures are contributing to larger atmospheric rivers—streams of water vapour that travel through the sky—over the West Coast. BC already has high levels of rainfall, but this atmospheric river will bring in more rain and even more snow.²The mountains nearby can complicate matters, and can contribute to landslides such as the one we witnessed last November.

Because rain and snowfall aren’t evenly distributed, other parts of the country—mainly the Prairies—experience drought. These areas are expected to heat up and dry out, which could have a devastating effect on our forests and agricultural systems.

We’ve seen the effects of changing climates on people—from geo­graphic displacement to loss of livelihood. How do changing seasons affect animals?

Temperature is a key factor in all living things’ metabolic processes. Temperature changes can cause disruptions in everything, from habitat and food availability to migration patterns and mating patterns. Predators and prey are two of the most common examples. Consider birds that feed on caterpillars. Some species of birds might not be able adjust to climate change if caterpillars are arising earlier due to climate change.

Our seasons are already looking—and sounding—different because of these changes. Some species of songbirds, such as the spring ephemeral and spring wildflower, arrive earlier or later due to rising temperatures. Trees are also beginning to bloom earlier.

What are the effects of these changes on your life?

A glacier covered almost all of North America’s historical maps from around 20,000 years ago. As the temperature rose, the glacier began retreating, opening up more space to the north and allowing species of migration.

That process occurred over thousands and thousands of years, but the changes we’re seeing now are much faster than before humans were in the picture. There are biophysical limits to how far a species can disperse, and ecologists are concerned that organisms can’t migrate quickly enough to accommodate the changes. One big consequence? More species are going extinct.³

Humans need to adapt to disrupted natural rhythms. The ecosystem changes when animals change their migration patterns. It is easy to see why this is important, as we rely on the system for food, shelter, water, and other essentials.

1. Geophysical Research Letters published a study that found that the average length of the summer weather in the northern part of the hemisphere increased by ninety-five to ninety eight days between 1952 and 2011.

Sebastian Leck. This interview was edited for clarity and length.

Madhur Anand is author of the book. A New Index to Predict CatastrophesThe memoir-in-halves This Red Line goes straight to your heartBoth books were published by Penguin Random House Canada. She is a professor of ecology at the University of Guelph and was the inaugural director of Guelph Institute for Environmental Research. She is also a member the Educational Review Committee of The Walrus.

Irma Kniivila, an artist and illustrator, has just completed projects for Marvel Comics and Boom! Studio’s Joyride.