Daryl Ritchison, WDAY, Published March 21 2013
Weather Talk: Comparison with temps from last March flawedWith the significant temperature differences between March 2012 and what has been recorded this month, comparisons are inevitable. One I have read several times is that last March was more than twice as warm as this year. A year ago, Fargo-Moorhead recorded several days in the 60s and 70s. This year it has been mainly in the 20s. So just looking at the numbers, you would think such a statement would be factually correct, yet it is not.
Surface temperature readings in the United States are given in degrees Fahrenheit. If we used the Celsius scale, the temperatures last March would have been in the 20s and this year below zero, obviously not “twice as warm.” Therefore, representing temperature differences in fractional terminology is not correct unless your starting point is absolute zero and you state the scale you are using.
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