The slow slide into drought
The current Prairie moisture situation is the result of years of ongoing precipitation deficits
Daniel Bezte
We had a fairly major storm system on the Prairies last week, but it was not strong enough to warrant major attention.
Manitoba received the most moisture from this system, with widespread 20 to 30 millimetres of rain mixed with snow. The northern half of agricultural Saskatchewan, along with the far eastern regions, also saw totals ranging from five to 15 mm. Parts of southern and central Alberta had precipitation, mostly as snow, with amounts ranging from four to 12 cm.
While this moisture is welcome, it will do little to alleviate drought conditions ([url]https://www.manitobacooperator.ca/news-opinion/news/another-drought-year-maybe-not-so-much/[/url]) that have been developing across the Prairies for several years.
The last time we looked at weather data, I showed it in tables because it seemed the best way to get the information across. This time I created a series of graphs to tease out precipitation. I looked at yearly precipitation for two main centres in each province going back five years (2018-2023).
The first graph shows the precipitation anomaly for each location over those five years, done by adding up precipitation each year compared to the average amount for each year. What jumps out at me is the precipitation deficit in Regina and Saskatoon. Both locations have received 700 mm less than average. Calgary and Edmonton had much lower deficits, around 200 to 300 mm.
The second graph shows yearly precipitation totals for each location compared to average. What jumps out to me right away is that very few locations and years were above average, which shows why the Prairies have been slowly slipping into a longer-term drought.
The third graph shows precipitation at each location over the last five years. Like the first graph, it helps to visualize total amounts without considering averages. Of interest is that totals for Winnipeg, Brandon and Edmonton are close to each other and Calgary is only a little behind. As expected, Regina and Saskatoon received much less precipitation than the other locations, more than a metre less.
The fourth graph breaks total precipitation into yearly amounts. There is not a lot of difference between the years, but 2022 was a wet year for Winnipeg and Brandon.
There is no obvious cause for the build up of drought conditions, such as a couple of super dry years. Rather, the slow lack of precipitation over the past five years has brought us to this point.
We have also seen several summers with well above average temperatures across the Prairies, which increases evaporation and evapotranspiration and makes below average precipitation even worse It will take more than a couple of wet months to bring an end to the drought. Hopefully, with El Nino coming to an end, we will see a shift toward a wetter pattern.
[url]https://www.manitobacooperator.ca/weather/the-slow-slide-into-drought/?utm_source=GFM+Publications&utm_campaign=8cd457db 39-Manitoba+Co-operator+daily+enews+Apr+30%2C+2024&utm_medium=ema il&utm_term=0_2da8244677-8cd457db39-%5BLIST_EMAIL_ID%5D&mc_cid=8cd457db39&mc_eid=006b2 8ff62[/url]
The current Prairie moisture situation is the result of years of ongoing precipitation deficits
Daniel Bezte
We had a fairly major storm system on the Prairies last week, but it was not strong enough to warrant major attention.
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Manitoba received the most moisture from this system, with widespread 20 to 30 millimetres of rain mixed with snow. The northern half of agricultural Saskatchewan, along with the far eastern regions, also saw totals ranging from five to 15 mm. Parts of southern and central Alberta had precipitation, mostly as snow, with amounts ranging from four to 12 cm.
While this moisture is welcome, it will do little to alleviate drought conditions ([url]https://www.manitobacooperator.ca/news-opinion/news/another-drought-year-maybe-not-so-much/[/url]) that have been developing across the Prairies for several years.
The last time we looked at weather data, I showed it in tables because it seemed the best way to get the information across. This time I created a series of graphs to tease out precipitation. I looked at yearly precipitation for two main centres in each province going back five years (2018-2023).
The first graph shows the precipitation anomaly for each location over those five years, done by adding up precipitation each year compared to the average amount for each year. What jumps out at me is the precipitation deficit in Regina and Saskatoon. Both locations have received 700 mm less than average. Calgary and Edmonton had much lower deficits, around 200 to 300 mm.
The second graph shows yearly precipitation totals for each location compared to average. What jumps out to me right away is that very few locations and years were above average, which shows why the Prairies have been slowly slipping into a longer-term drought.
The third graph shows precipitation at each location over the last five years. Like the first graph, it helps to visualize total amounts without considering averages. Of interest is that totals for Winnipeg, Brandon and Edmonton are close to each other and Calgary is only a little behind. As expected, Regina and Saskatoon received much less precipitation than the other locations, more than a metre less.
The fourth graph breaks total precipitation into yearly amounts. There is not a lot of difference between the years, but 2022 was a wet year for Winnipeg and Brandon.
There is no obvious cause for the build up of drought conditions, such as a couple of super dry years. Rather, the slow lack of precipitation over the past five years has brought us to this point.
We have also seen several summers with well above average temperatures across the Prairies, which increases evaporation and evapotranspiration and makes below average precipitation even worse It will take more than a couple of wet months to bring an end to the drought. Hopefully, with El Nino coming to an end, we will see a shift toward a wetter pattern.
[url]https://www.manitobacooperator.ca/weather/the-slow-slide-into-drought/?utm_source=GFM+Publications&utm_campaign=8cd457db 39-Manitoba+Co-operator+daily+enews+Apr+30%2C+2024&utm_medium=ema il&utm_term=0_2da8244677-8cd457db39-%5BLIST_EMAIL_ID%5D&mc_cid=8cd457db39&mc_eid=006b2 8ff62[/url]
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