How the Climate has Already Changed in Waterloo Region

This blog post deals with changes that have already occurred in our local climate over the past century.  A future post will address the changes in weather patterns that climate models predict are coming to the Waterloo region.  

Globally, average annual temperatures have risen by 0.8’C  since pre-industrial times[1].  But this rise in temperature is not uniform over the whole planet.  The poles, for example, have warmed much faster than other regions, including the Region of Waterloo. The graph above shows how average annual temperatures have changed in the region since 1915[2]. Although the change is not dramatic yet, it is clear that temperatures are rising here too.  The trendline in the graph above suggests that our average annual temperature has increased by 0.4'C since 1915.  

But climate doesn’t simply describe annual temperatures, it encompasses precipitation patterns, seasonal transitions, extreme weather events and much more.  In the Waterloo region, Climate Atlas shows that we have already, in the last 70 years or so, experienced a rise in very hot days (+30’C), an increase in the frost-free season, a rise in the annual minimum temperature, and many other worrisome trends. 

You may personally also have noticed changes to our weather patterns here in Waterloo Region.  I have observed that there are fewer good ski days in the winters, less snow accumulation, more mid-winter thaws, earlier frost-free days in spring, more erratic precipitation in summer... 

What about you?  Have you experienced long term changes in our Region’s weather patterns? Katherine Hayhoe, climate scientist and climate communicator gave a TEDtalk that has received over 1.9 million views in just over a year.  The key message of her TEDtalk:  The most important thing you can do to fight climate change is talk about it.  Your personal experiences of changing weather patterns may be one of the best ways to start a conversation.    


[1] https://climate.nasa.gov/vital-signs/global-temperature/
[2] data sourced from Environment Canada website using Kitchener weather station (1915 to 1977), Roseville weather station (1978 to 2010), Kitchener-Waterloo weather station (2011-2019)