When Virginia Wittrock speaks to farmers about climate trends in Saskatchewan, she tries to avoid the phrase “climate change.”
The words are politically charged and can get in the way of rational discussions about the climate.
Instead, Wittrock prefers to let her data tell the story — data that’s been collected daily over the last 55 years at the Saskatchewan Research Council’s (SRC) Climate Reference Station in Saskatoon.
So what does the data say? Is Saskatoon’s climate different than it was 55 years ago?
Without a doubt, says Wittrock, a research scientist and climatologist who’s been working at the SRC for the past 31 years.
“Our winters are definitely getting warmer, our summer night-time temperatures are definitely getting warmer and summer precipitation seems to be getting more variable,” she says.
The average frost-free growing period is also getting longer.
In fact, SRC trendline data suggests the average frost-free growing period in Saskatoon has increased to nearly 140 days currently, up from about 106 days in the mid-1960s.
Climate data collection — and the unbiased interpretation of it — are Wittrock’s areas of expertise.
A Saskatchewan-born researcher, Wittrock grew up on a family farm not far from Swift Current, Sask., and studied physical geography (BSc) and climatology (MSc) at the University of Saskatchewan.
Because of her farm background, Wittrock is comfortable talking with farmers about climate. She speaks their language and understands the challenges they face.
“I’ve always been intrigued with the weather and climate,” she explains.
“When I was a kid, I would go to coffee row with my dad … and all the guys there would be asking what’s up with this weather? Why is it doing X, Y and Z?
“I thought, maybe I can help a little bit by trying to figure out some of this stuff.”
Wittrock describes the SRC’s climate reference station (CRS) as one of the most comprehensive weather data collection sites in the country.
It measures temperature, precipitation, solar radiation, wind speed, soil temperature, surface temperature, barometric pressure, humidity and snow cover several times a day at pre-determined intervals.
Over 55 years, it has generated a massive amount of data.
Wittrock uses that data to arrive at an unbiased interpretation of how the climate has changed over the past half-century, and how it’s likely to change in the future.
When asked what the SRC’s climate data suggests about future challenges for the province’s agricultural producers, Wittrock says pest control, disease control and the adoption of new crops and new crop varieties will be key considerations.
For example, SRC data suggests that average winter temperatures — both average highs and average lows — are increasing.
The trendline for average winter minimum temperatures has increased to about -16 C currently from nearly -22 C 55 years ago.
Over the same period, trendlines suggest that the average number of days each year with temperatures below -35 C has decreased to zero currently, down from nine previously, and that the average number of days annually with temperatures below -30 C has decreased to approximately 2.5 currently, down from 25 a year in the mid-1960s.
The trend toward warmer winters will continue in the coming decades and will result in new pest- and disease-related challenges, Wittrock says.
She points to the expansion of the tick populations throughout the province’s farming region as evidence that insect species are becoming more adept at surviving the Saskatchewan winter.
“The insects are going to overwinter a lot easier. We’re already seeing that,” she says.
The length of the frost-free growing season in Saskatoon is also increasing, and growing degree days during the growing season show a steadily upward-rising trendline.
Based on her data, cumulative growing degree days between May 1 and Sept. 30 have increased, on average, to nearly 1,700 currently from less than 1,500 in the mid-1960s, a trendline increase of roughly 13 percent.
That suggests that in the future, Saskatchewan farmers may be inclined to grow different crops that require more heat units, such as corn and soybeans.
Wittrock cautions however that annual and seasonal variabilities, both in temperature and precipitation, will continue to frustrate such efforts.
In fact, statistical evidence already suggests that Saskatoon is experiencing greater weather variability, and that extreme weather events are occurring more frequently than they have in the past.
The spring of 2019 was the driest spring ever recorded at the climate reference station, she says.
“We’ve also noticed more extreme summer time rain events — both floods and droughts — that are incredibly hard to forecast,” she adds.
If extrapolated to a wider geography, that suggests the task of growing agricultural crops may become more challenging in Saskatchewan and will be more dependent on crops and seed varieties that are adaptable to a wider range of growing conditions.
Although there’s a segment of the farm population that is reluctant to acknowledge that the prairie climate is changing — or perhaps that climate change is a result of human activity — Wittrock says Saskatchewan’s agricultural growers are already feeling the impacts of climate change and are changing their management practices accordingly.
Farmers are astute operators that adapt quickly and can change their management techniques, she says.
Public awareness about the prairie climate is changing, she adds.
People are taking notice because they sense that “something weird is happening.”
When asked if the trendlines that have emerged over the past 55 years are likely to change course, Wittrock’s response is decisive.
“Not a chance,” she says.
“You’ll still get your annual and seasonal and daily (anomalies) … but on the average, our winters will keep getting warmer. We might have a year, or two, or even five where we’ll have a cold snap, but on average, the trends will keep going up.”
Annual summaries of Wittrock’s CRS weather data can be viewed online at www.src.sk.ca/download-weather-summaries.