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Cooler July, thanks to farmers and canola

Swift Current temperature data shows different long-term trends in January versus July

canola flowers

This piece is a result of the Canola Discovery Forum at Canola Days in Saskatoon in December, 2017. Jay Whetter, former editor of Grainews and now communications manager with the Canola Council of Canada, invited me to address the issue of precision agriculture with specific reference to the role soil maps might play.

My contribution was very small but I learned a lot that day. It was a very well run program — a class act and an honour for me to attend and learn.

The feds (Agriculture and Agri-Food Canada) still play a very important role in canola — particularly disease and insect issues. The contribution of Hugh Beckie (AAFC, Saskatoon) in weed control, particularly resistance issues, has been outstanding. Unfortunately we are losing him to Australia. Good luck Hugh.

Canola as a cool crop

A highlight for me was the final talk by Brian McConkey, AAFC Swift Current. Brian has many years of experience dealing with climate change issues. The title of his talk was interesting: “Why canola is a cooler crop than cereals.” Of course I thought he was talking about “cool” as a teenager puts it. I assumed he would talk about how “cool” it is to make all that money growing canola.

But he was talking about the reflective nature of the beautiful and prolific canola flowers that reflect heat back where it came from. It is much the same idea as the cooling effect of snow. Thanks Brian.

Given the same solar radiation, my anecdotal evidence suggests that snow vs. bare ground is good for about 5 C for the same amount of sun. I recall a one-hour trip from Outlook, Sask., to Saskatoon in April, driving one of the first cars with an outside temperature readout. The snow was all gone at Outlook, but about 20 minutes north the snow line appeared. The temperature dropped a few degrees very quickly. In spring, all one has to do is watch The Weather Network on a widespread clear day and the snow line can be read from the air temperature.

Canola is not going to give that kind of cooling, and the effect only lasts a few weeks, but at least canola is doing its part to keep it cool so flower blast is minimized.

A primer on drought

While cleaning out boxes of files at the University of Saskatchewan I stumbled on “Drought in the Palliser Triangle: A Provisional Primer,” a 58-page bulletin published in January 1998 by the then PFRA. The main author was Walter Nemanishen, who had been a planning engineer and the author of many papers related to Prairie droughts and floods. It was an interesting compilation of climate data with a great reference list I will use for further knowledge. They showed Medicine Hat rainfall data with a huge drought from 1917 to 1926. We have all heard about the “Dirty Thirties,” but I did not know about the 1917 to 1926 issue. That “Dry Belt” went north from Medicine Hat, Alta., to Alsask, Sask., west to Hanna, Alta., and east to Rosetown, Sask.

It was their final conclusions that: “The Prairies continue to be vulnerable to drought,” and further that “The drought causing weather patterns are now recognizable and can be used to predict drought.”

Twenty years later I have not seen anyone rushing out to predict a drought. Climate warmers scream drought after it has not rained for a few weeks but I see no one predicting it.

The PFRA document related hot June-July months to drought and listed 1987, 1988 and 1989 as well as 1970 as the four hottest on record. Seeing the 1980s on the list was no surprise to this old fossil. I will long remember June 5, 1988, as the hottest day I have known (40 C at Saskatoon). And, the Saskatchewan Soil Moisture maps in 1987 and 1988 were full of red ink (indicating very dry).

The 1970 hot spot was interesting. How many readers are long enough in the tooth to remember 1970? Wheat markets were in the tank and farmers were sitting on huge surpluses that the world market did not need. The feds responded with the LIFT (Lower Inventories for Tomorrow) program. They paid farmers to summerfallow fields two years in a row. Summerfallow is bare ground for sure. It absorbs and re-radiates the heat to increase air temperature.

Which brings us to the final argument — the climate cooling effect of doing away with summerfallow.

Summerfallow as a heat engine

When the early settlers came up with the slogan “rain follows the plough” they were dead wrong. The plough-bare ground makes heat, which reduces the rain.

A paper published in 2006* concluded that 1976 to 2000 climate trends from mid-June to mid-July in the Brown, Dark Brown and Black soil zones saw maximum temperatures decline by 1.7 C per decade. They also observed a 10.3 mm increase in precipitation for the same mid-June to mid-July period.

I once again give thanks to AAFC Swift Current folks Herb Cutforth and Jason Nimegeers for providing the data used in the figures on this page.

The 30-year average January temperature in Swift Current has a range of 6 C (see above). It’s easy to see the sharp rise from 1975 on. If you look at the data, February and March trends also show rises, but the other months, not so much. I’ve used a 30-year period as that is generally what separates climate from weather.

The July data is not the same. The first thing to note is that 30-year average temperature for July has a range not much more than 1 C (see below). The data also clearly shows that July is a month that is getting cooler, not warmer.

x photo: Source: AAFC data

Thanks farmers for doing away with that wretched summerfallow that was burning us up. Thanks canola for your pretty and light-coloured flowers that help to keep our summers cool and comfortable for crops and mankind.

In the light of all the above, a federal carbon price is not the answer. It makes no sense to me. At the many meetings I attend where a long line of “experts” say we are heading to you-know-where in a handbasket, I always have two questions:

  1. What thermometers and what months are averaged to come up with the “global” temperature? And,
  2. How did all the ice from the last glaciation melt with not a fossil fuel in site?

I have yet to receive an answer.

*The full reference for this paper is:“Gameda, S., Qian, B., Campbell, C.A. and Desjardins, R.L. 2006. Climatic trends associated with summerfallow in the Canadian Prairies. Agriculture and Forest Meteorology vol 142 pages 170-185.”

About the author


Les Henry

J.L.(Les) Henry is a former professor and extension specialist at the University of Saskatchewan. He farms at Dundurn, Sask. He recently finished a second printing of “Henry’s Handbook of Soil and Water,” a book that mixes the basics and practical aspects of soil, fertilizer and farming. Les will cover the shipping and GST for “Grainews” readers. Simply send a cheque for $50 to Henry Perspectives, 143 Tucker Cres., Saskatoon, Sask., S7H 3H7, and he will dispatch a signed book.



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