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We begin this week with a subject at the very core of the Canadian psyche. And it's a subject Collected Wisdom hopes we soon won't be talking about for quite a while — snow.
THE QUESTION: How is snowfall measured (to avoid errors due to drifting)? Ted Pope of Caledon, Ont., wants to know.
THE ANSWER: At meteorological stations the measuring instruments are deployed in an area free of obstacles such as buildings, fences or other structures or topographic forms that could cause turbulent air-flow at ground level and interfere with the accurate measurement of snowfall, writes Bruce Findlay of Toronto, who is retired from the Meteorological Service of Canada.
He informs us that an observer measures the depth of freshly fallen snow with a ruler at several spots until he or she can be sure of an average accumulation since the last measurement.
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"In an ideal world, the observing station is said to be 'representative,' or typical of the landscape of an extensive area," he says. However, for practical reasons, stations are aften located at places like airports, "which are open to strong winds causing snow drifting and making averaging more difficult."
The deepest snows, he says, accumulate in topographic hollows or in small clearings in a forest, while the shallowest covers are over large bodies of frozen water.
Richard Bryer of Toronto, who used to work for Environment Canada many years ago when it was called Atmospheric Environment Services, adds: "Measuring snowfall was probably the most subjective of all our measurements. However, we used to say: 'We may not be right but we are official.' "
THE QUESTION: Continuing in a chilly vein, Bill Somes of Sarnia, Ont. wonders how ducks and geese can swim in frigid water and not experience any apparent damage or pain in their feet and legs.
THE ANSWER: "Ducks and geese keep their legs and feet cold, to within a degree or two above ambient temperature — but always above freezing," writes Ben Speers-Roesch of Vancouver.
"The arteries carrying blood to the legs from their warm, insulated bodies pass adjacent to the veins returning from the cold feet. The arterial blood warms the venous blood in a process termed countercurrent heat exchange. Blood flowing into the leg therefore gets colder, but loses its heat to blood returning to the body, not to the environment. This conserves body heat while allowing proper blood flow to the legs and feet."
Lane Stanley of Whitby, Ont., adds: "Birds' legs are made almost entirely of bone and tendons, which require less heat to work properly than muscles or organs."
HELP WANTED
What is the origin of the term "kangaroo court"? asks Mary Millar of Mississauga.
"Entrée" means "entrance," which makes perfect sense on a menu in Europe where the entrée is the first course of the meal, writes John L. Henry of Vancouver. So why in North America is the term used to describe the main course, which makes no sense?
Why are the bridges on cruise vessels and liners at the bow and those on container ships and oil tankers at the stern? asks Ottawa's Pat Clarkin.
Send answers (and questions) to wisdom@globeandmail.com. Include your name, location and a daytime phone number.
