Wind Chill in Northern Canada1

Abstract

Man has talked about the weather since the beginning of time. Frequently these discussions and arguments have concerned relative coldness, that is "whether last Tuesday" or, "that cold day last winter", was colder than this morning. During these thousands of years, man has invented various method6 of protecting himself from the weather. He has learned to wear clothing, to find or build himself a dwelLing, and more recently, to heat his dwelling in cold weather, to ventilate or cool it in hot weather, and even to control the humidity.Man has aIso devised methods of measuring the weather elements. Over three handred years ago he invented the thermometer and used It to measure the temperature of the air. He found that it gave higher readings ia the SUB than in the shade. Now he hae discmered why the readings are different and bas learned to measure solar radiation, and other elements that affect his comfort, such as humidity and wind speed. Rowever, the arguments still continue: "Is it cdder in Halifax when the northwest wind p&es the temperature down to zero, or in Saehatoon on a calm, 8-yday with the temperature thirty belaar?"It muet be admitted that coldness, for most of ue, is not a simple matter of low temperature. curie2 attempted t o measure this coi-tke only available instrument which would give the correct answer: tlre hnaran body. Only the haman body can measure how cold the weather feels. The studeate who helped Professor Currfe at the University of Saskatchewan aggreed qulte well about how cold it was each winter morning on their way to lectures. Their coldness aensatians were plotted on a diagram using temperature and wfnd speed a8 e e s , and implethe of i ens at ion were drawn and labeled with such berms ;LB cud., cold, and bitterly cold. Currid B diagram shows haw coldness depends on wind speed, but it does not take into account other hctors snch as humidity and s o h radiation. and the amount of his clothing. Thfs may influence his estimate of the coldness of the weather. Currie kept these factors fairly constant by using only the reported sensations of students who were walking or waitingior tranoportatian and who were similarly clothed. However, the sensations of a group of students at IZafhonsie University in Nova Scotia would probably produce a quite different diagram due to differences in clothing habits and in the weather thet areaccaatomed to. It is obviously necessary to have some &vice which is much simpler than using students as an instrument to measure coldness. The rates of loss af heat from other objects must be measured and these rates assumed to indicate the rates of loss of heat from exposed flesh, This in turn will indicate whether CIothing is required to keep a human being comfortable.The coldness of the body also depend8 on the am& d ~c t i v i t y of the personThe same thing could be expressed samewhat differently. What is required isPresented at the January 1957 meeting of the Southern Ontario Division of the Canadian Association of Geographer6 in Hamilton, Ontario and Publishe...