The Prairies are heading into another drought. Here's why we're more vulnerable this time

In northern Alberta, a worrisomely dry winter has raised some fears about an issue that hasn't historically been a problem — drought. 

"Up towards Slave Lake, we'd expect about 50 millimetres [of water] this coming year," said John Pomeroy, a University of Saskatchewan water scientist. 

"We had five. So one–tenth of normal."

It's a similar situation southwest of Edmonton, where the snow pillow — a device used to measure snowpack — between the North Saskatchewan River and the Athabasca River is far worse than last year.

That snow pillow is recording just over 139 millimetres of water equivalent in the snowpack, which is well below average for this time of year, and is even below the lowest quartile.

Even more concerning, things would be looking a lot worse in northern Alberta if it wasn't for the impact of another climate catastrophe in the making, Pomeroy said. 

"Parts of northern Alberta were quite fortunate last year because glacier melt helped keep the North Saskatchewan River higher than other rivers in the province," he said.

The record melting, along with some big rainstorms in early June, impacted the headwaters of the Athabasca as well as the North Saskatchewan, raising water levels in rivers, streams, and other sources of groundwater. 

But that's not a sustainable solution, Pomeroy said.

Some of Alberta's glaciers will be gone in a decade, which means some parts of the province won't have that drought security net, he said. 

"With those melt rates, those glaciers would not be around in the long term." 

A breakdown of recent Prairie droughts 

In late January, the Alberta government established a drought command team, which is working to finalize the province's emergency drought plan as a dry year looms. 

The province also declared a start to the wildfire season 10 days earlier than usual due to concerns about a continuation of last year's severe forest fire season. 

In recent years, the Prairies experienced a few extreme droughts, with the 1988–89 and 2001–02 droughts often described as some of the worst.

The 2001-02 drought cost the national economy $5.8 billion, making it one of the most costly natural disasters in Canadian history. Though its impact was worst on the Prairies, it was the first coast-to-coast drought on record. 

In 2009, there was another severe drought that — at the time — was considered the driest in 70 years. Ten communities in central and northern Alberta declared states of emergency, while Saskatoon recorded less than a quarter of its normal precipitation. 

That record was broken in 2021. That drought is ranked as the most severe in 60 years, and far worse than the Dust Bowl of the 1930s —  which many still assume is one of the worst droughts in North American history. 

David Sauchyn, director of the Prairie Adaptation Research Collaborative at the University of Saskatchewan, said his grandparents abandoned their homestead in Hanna, Alta., and moved closer to Edmonton. 

"The drought of the 1930s, meteorologically, wasn't that bad, people just weren't prepared," said Sauchyn. "My grandparents had to abandon our homestead in Alberta and move near Edmonton, where I grew up."

Reading the tree rings 

Environment Canada has records for weather and precipitation dating back to the 1870s, but to trace weather patterns before then, some experts are turning to tree rings. 

The rings tell a story of extreme historic years–long droughts, with dry years appearing in tree trunks as smaller, narrower rings. 

"The tree growth will be limited by the amount of moisture available each year," said Sauchyn. 

"So that's how we're able to reconstruct what the moisture has been in the soil and the lakes and the rivers every year back more than 1,000 years."

Sauchyn says the most valuable information tree rings offer is a look at the climate in the years before weather stations became a reliable source of information. 

"Of course we have observations of drought, we have weather station records, but they go back at most to the 1880s at a few locations," said Sauchyn.

"They're very critical information about precipitation and evaporation and drought, but they capture only a limited number of really bad droughts."

But what do tree rings say about future droughts? Sauchyn says not much, but they can be used to compare the change in the climate before and after the Industrial Revolution.

"We can actually use the tree rings record to test or verify whether the climate models are able to simulate or replicate the natural climate of the prairies that existed before we began to seriously modify the climate," said Sauchyn. 

Climate models got precipitation wrong

According to Natural Resources Canada, droughts in drier parts of the Prairies will become increasingly severe. As well, those conditions are expected to creep northward to areas like the Boreal Plains ecozone, that haven't typically been affected.

Some early climate models suggest that as global climate change warms the atmosphere, arid and semi-arid lands should also see a rise in vapour — or precipitation — in the atmosphere. 

These models were based on the scientific premise that as the atmosphere warms, it should hold more moisture. 

However, a study released in January by the U.S. National Science Foundation National Centre for Atmospheric Research found that arid and semi-arid lands are getting hotter, but not wetter.

Pomeroy says Alberta — which is mostly semi-arid — is in fact getting warmer, with no increase in precipitation.   

"It's a bit of a wake-up call [that] climate models can get the precipitation wrong," he said.

Sauchyn says that even though the Prairies have experienced extreme droughts in the past, the influence of human-induced climate change will only make future droughts worse.

"It was quite a bit cooler back then," he said.

"These droughts that occurred in the past will reoccur in the future — but they will occur in a climate in which the warm season is longer."

Sauchyn says that despite the concerning trends of warmer, drier conditions, cities and provinces are more prepared to respond to the changing climate. 

He says the launch of the drought command team is a sign the province is taking the issue seriously. 

"Very often when there's a water crisis, we end up with reactions after the fact … to start planning this out beforehand is very, very prudent," said Pomeroy.

"We might be lucky, it might get hit with rain in the month of April, and we'll be fine."