Drought

Thanks to the 100+ people who attended my presentation for the Bruce County Genealogical Society on Monday evening.

One of the questions asked was whether the drought in the Prairies in the 1930s, known as the Dirty Thirties or Dust Bowl, extended into Ontario. I didn’t know, although I  said I suspected it did.

Here’s a comparison between Regina’s and Toronto’s annual precipitation from 1929 to 1939, the number in the top line is the climatological average annual precipitation in millimetres.

Both show a median annual precipitation deficit for the period. Regina had 6 years that were 20% below the long-term mean of 397 mm, whereas Toronto had two such years, below 790 mm. For only one of the years, 1934, did both cities have 20% less precipitation than the climatological average.

That is probably further into the weeds than most family historians care to venture.

In case you want to venture a bit further, for agriculture, precipitation is only part of drought. Hot, dry conditions mean greater evaporation, so less moisture for crops. That’s quantified by the Palmer Drought Severity Index. Decadal maps are available at https://cfs.nrcan.gc.ca/fc-data-catalogue/read/4 . The earliest is for 1951-1960

Even over a 10-year average, conditions across the southern Prairie provinces ranged from severe drought to very wet. For annual and shorter periods, the variation would be greater. For instance, for 1929, there was a 29% precipitation deficit at Regina, a 40% deficit at Medicine Hat, but at Lethbridge precipitation was 17% above average. 

Check out current conditions, as of the end of May, at https://agriculture.canada.ca/en/agricultural-production/weather/canadian-drought-monitor/current-drought-conditions#a5

Although chances are your Prairie ancestor had a hard time during the Dust Bowl, maybe they were among the few that Mother Nature blessed with just enough rain or snow to maintain a harvest.