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Name: Carrie
Status: Student
Grade: 4-5
Location: CA
Country: United States
Date: Spring 2010


Question:
In our class we learned that the water molecules in the ocean on stay for an average of 3000 years. We were wondering how scientist know this? What is their method of measurement?



Replies:
Your challenge is to be commended. It challenges the misuse of the concept of "average". I do not know of any scientists who make any such claim, except as a "back of the envelope" estimation -- knowing that the estimate is just for fun. Be aware that just because you learned the assertion in class "makes it true".

Your next response (that you implied, but did not quite say it (probably out of respect for your teacher) should be:

SHOW ME YOUR DATA!! SHOW ME HOW YOU ANALYZED THE DATA!! WHAT IS THE DEVIATION OF THE DATA FROM THE AVERAGE!!

I challenge the authors who wrote that claim to provide credible answers to the challenges above and any number of other ones that one might pose. You ask the right question, "What is their method of measurement?"

An A+ for challenging that assertion. My personal opinion, keeping in mind that it too is an opinion not supported be data, is that the 3000 year estimate is "garbage science".

Vince Calder



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