I was more than a little confused when the (magnitude 4.4) May 17 Shawville earthquake was persistently described by the media as being magnitude 5.2. Canadians are totally insecure about their place in the world so, when it comes to reporting the environment, bigger is better. Of course this also makes for attention-getting headlines.
We know this to be the case for television weather-reporting, where summer temperatures are made to appear warmer through use of a humidity index, and winter temperatures made colder by using a wind-chill index.
It turns out that Canadians do something similar for certain earthquakes by using a Nuttli magnitude index. Apparently, "Canadian seismologists will often refer to the Richter magnitude whereas strictly speaking the seisms that occur in Eastern Canada are measured according to the Nuttli magnitude. An exception exists for the very small earthquakes of the Charlevoix Region, where the Richter scale is used." An exception with an exception. Nice.
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