Percy Saltzman Essay: The Snow-Eater

Sunday, March 16,1952.

(CBC Trans-Canada Network)
The Snow-Eater
P. P. Saltzman,
Dominion Public Weather Service, Toronto

The world's dictionary of weather words contains dozens of fascinating. items. Words like sun dogs, corona, silver thaw, St. Elmo's fire, and aurora borealis. Canada has contributed two of the best of them. One is fearsome and awe-inspiring--the dread blizzard. And the other sounds gentle and friendly- the Chinook.

The word Chinook is widely known, but not so many perhaps know what it is. There are many who do, however, especially the people who live or have lived in the Chinook belt--that part of. southern Alberta from Claresholm in the north to Waterton in the south, from the Rockies on the west to Medicine Hat in the east. To those people the Chinook is the snow-eater. It's the warm, dry west wind that blows down from the Rockies in winter, raising temperatures at a remarkable rate, and literally eating up the snow before your very eyes. :Many a rancher has had reason to be thankful for the Chinook, for entire herds of cattle have been saved from starvation by the timely removal of the deep snow.

Tall tales have been told of the fiery Chinook. Let us lean back and regale ourselves with a few of them. A farmer once drove his team and sleigh to town one freezing winter day, and a Chinook blew up. Realizing his danger, he started home at a full gallop. The front of the sleigh ran smoothly over the deep snow, but the rear runners dragged in the mud. Reaching home safely, he rushed to the house to have an early dinner--he wanted to start plowing that afternoon.

Tall enough? This one's still better. An even smarter man kept runners on the front of his sleigh and wheels on the rear end, so that by travelling at the same speed as the Chinook, he had no trouble getting home--no trouble at all.

Other yarns have it that people in the Chinook belt have a pronounced lean to the west. They grow that way to counterbalance the Chinook wind but when it ends suddenly, they fall right over--to the west, I suppose. And when you lose your hat in a Chinook, you never chase it--you just wait a minute and another hat will come along.

As Clarence Thompson, one of our Edmonton forecasters, said: "I've played golf .in January at 65 degrees, knowing full well that if it weren't for the Chinook it could be 40 below. I've seen a Chinook in a vicious mood ripping off precious topsoil. I've felt the impact of its wind 97 mph. I've seen lilacs bud in February and grain threshed in the field in January."

Yes, Chinooks have been known to raise the temperature as much as 60 degrees in a matter of minutes. In southern Alberta you can see how many trees have been hammered on one side by the force of the snow-eater. Pilots have reported Chinook winds aloft with speeds well over 100 miles per hour. The Chinook, however, isn't always violent. It can be as gentle as a breeze. It may last three or four days or it may come in short spells, interrupted by colder and calmer intervals.

The Chinook gives southern Alberta the longest growing season on the prairies. It enables the farmers to plough and seed very early. And if you take into account the assistance rendered by irrigation, the Chinook belt really flourishes with an abundance of sugar beets, peas and corn, all the fruit of the Alberta snow-eater.

We recently received a letter from Miss Edith Thompson, teacher in Carman, Manitoba. She asked about the Chinook. The Chinook, she writes, rules the day. Miss Thompson went on to say:

"The queer formation of the Chinook Arch was a constant source of mystery to me-- no one could give a logical explanation of it.

"We would be under the Arch and in the cloud area for perhaps a day--while the prairie and mountains were in Sun--the wind would be blowing a gale--then soft, white cumulus clouds would form and the Arch would continue a while longer and then disintegrate. The Chinook wind might last a while longer--put what caused the Arch? With such a wind--how did the clouds stand still?"

Well, the old saying has it that coming events cast their shadows before and the Chinook is no exception. Often when it is about to chinook, a bank of cloud forms just east of the Rockies. This cloud is more than two miles above the surface of the earth, so that you can see clear air underneath it as you look to the west. The bank of cloud runs north and south, parallel to the Rockies, and at either end, it seems to bend or arch as it disappears over the horizon. Hence the name of this bank of cloud--the Chinook Arch. The startling beauty of a Chinook Arch, brilliant red at sunset, is a sight long to remember and familiar to many Canadians. Oldtimers are happy when they see the arch, for they know it will chinook before morning.

As to why the clouds of the Chinook Arch stand still although the Chinook wind is blowing strong, that can be readily explained by comparing the Arch to a whirlpool in a stream. The whirlpool is stationary even though the current of water flows right through it. The whirlpool remains the same although the water in it is never the same. In similar fashion, the air stream that produces the Chinook Arch moves right through it, yet the Arch stands still.

There is a very good reason too for the warmth of the Chinook. Mild and moist west winds blow off the Pacific ocean, and over The Rockies. As the winds lift over the mountains, clouds form and the moisture in the air comes out as rain on the oceanside of the Rockies. The western slopes of the Rookies are one of the areas of greatest rainfall in Canada. As the rain forms it adds heat to the air, and to top it off, when the air comes over the mountains and starts the down grade into Alberta, .the air is further warmed by compression. Hence the wondrous warmth of the snow-eater. Canada, of course, hasn't a monopoly on this kind of thing, and Chinook winds are found in the Alps, in California, and in the eastern Mediterranean. But they use different names, like Santa Anna, Foehn, and Sirocco. It was a Hudson Bay factor who named our wind the Chinook, after the tribe of Indians from whose village the Chinook appeared to come. The fame of the Chinook spread as early settlers moved into Alberta. They noticed how buffalo came to graze in the foothills of southern Alberta. Ranchers soon took advantage of this phenomenal climate.

And since those days the fame of the Canadian Chinook has continued to spread far and wide, as well it might, for the chinook is a truly fascinating feature of nature's handiwork.

FOOTNOTE: The following item appeared in the Lethbridge Herald, February 27, 1952; it provides an interesting footnote to the foregoing."

Chinook Lures Bear From His Den in Park

Waterton Lakes National Park (HNS )--Imagine the surprise of :Mrs. C. G. Carlson when Mrs. Ken Tailfeathers rushed into the house and cried excitedly, "There's a bear over by that house next door!" "Oh, you must be mistaken; it's probably a dog," replied Mrs. Carlson in a doubtful tone of voice. "Well, if it's a dog," answered Mrs. Tailfeathers, "it's a mighty big one." Later that day when the men returned from working on the ice, they went over to look for tracks. Sure enough, there were bear tracks around a hole under the old Moscovich house, next to the dance pavilion. The following day Mrs. Tailfeathers saw the bear again. That evening the men took over some meat scraps and threw them under the porch for the bear. He has not been seen since. For a number of years a black- bear has "holed up" for the winter under the house, now owned by N.W. Dilatush. Usually he stays asleep until spring. However, the three weeks of chinook weather must have deceived his bear instincts for he came out a month too soon. Mr. Carlson advances the theory that perhaps snow melted and ran under the cottage disturbing the bear from his slumbers.