By Robin Steedman-Braun
Science and Environment Editor
Wondering why the weather has been so unpredictable recently? You’re not alone, and it looks like we’ll have to get used to it as we adapt to this new normal of climate irregularity.
Record high temperatures this past summer have people concerned about what this winter has in store, and why the Earth’s usual climate patterns are changing so drastically.
The Earth’s tilted axis is the cause of our seasons. As the Earth circles the sun throughout the year, different hemispheres of our planet receive different amounts of sun and heat, causing periods of varying weather patterns, known as seasons. However, as greenhouse gas emissions increase our planet’s atmospheric temperature, extreme meteorological changes prevail. A recent study by the Journal of Geophysical Research Letters suggests that we could have six-month long winters by the end of the century, and that we can expect to experience only two seasons: winter and summer. Summer would be six months long, and winter only two, with fall and spring becoming short transitional periods.
While this may sound appealing to some, the consequences this will have on the Earth’s ecosystems are enormous and worrisome. Indeed, the changing seasonal clock will disturb agricultural practices as well as increase the risk for natural disasters such as forest fires, heat waves, and droughts. According to this study, in the last 60 years, from 1952 to 2011, the length of summer has already increased from 78 to 95 days. Prolonged warm seasons also lead to health risks for humans. Indeed, long periods of high temperatures lead to a greater occurrence of worrisome mosquito-borne diseases, such as malaria, dengue Zika virus and more. These diseases are much less prevalent in North America because the cold winters kill off the mosquitoes every year. However, with a six-month long summer, tropical mosquitoes, as well as the diseases they can carry, could travel north, and expand their habitat past the tropics.
These drastic temperatures can also have a devastating impact on wildlife. We are already seeing evidence of changing ecosystem patterns in response to atypical seasonal behavior, such as flowering plants budding early as well as premature bird migration. Animals are having an increasingly difficult time with these changes. For example, in Cape Cod, Massachusetts, sea turtles are being heavily impacted by unusually cold winters. As sea turtles are cold-blooded creatures who rely on the heat provided by their environment, when the water becomes too cold, they can develop a certain type of hypothermia, known as cold stunning. Cold stunned turtles experience reduced mobility, decreased circulation, and become lethargic, putting them at risk to be hit by boats or eaten by predators, if they are not already dead from hypothermia. Unusually cold weather patterns are putting more strain on our wildlife, threatening already vulnerable species, and by the year 2100, many of these species will be completely extinct.
As a result of climate change, summer and winter temperatures have become increasingly different, especially in mid-latitude regions of the Northern Hemisphere, which is right where Quebec is. Summer temperatures are increasing much faster than winter ones, causing a disparity between the two seasons. This explains our scorching hot summers being followed by freezing cold winters. High summertime temperatures are arriving earlier and lasting longer because of climate change. As many cities, including Montreal, still experience freezing cold days regularly during winter, the average number of days with temperatures below-zero is decreasing each winter across North America, worrying climate experts.
As for the chilly months ahead, there are high chances that we experience a “yo-yo” winter, with temperatures swinging from one end of the scale to the other. This drastic weather has become more and more common in the last ten years, and we have already had a glimpse of it this autumn. Nonetheless, ski bunnies should rejoice in the high amounts of snowfall expected in the upcoming frosty months. Expected cold fronts coming from the coast and Atlantic provinces mean a snowy, stormy, and icy January for southern Quebec. However, the stormy weather is expected to dissipate by February, and we can expect a relatively mild March. Just as September is now a summer month, March has become a winter month, meaning we should expect spring-like temperatures to start only in April, as a cold winter drags on. Time to bundle up.