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    My local time Vs UTC
    From: Steve E. Bryant
    Date: 2017 Jul 28, 21:00 -0700


    I live in Oklahoma City.  My longitude is 97.6297°W. We observe Daylight Saving Time.  Nevertheless, with that longitude, we are still identified in zone description -6; and, when observing DST, our zone description is -5.  [Note: 97.6297 divided by 15 degrees = 6.508, which would otherwise be recognized as a zone description of -7]. Our zone description is accepted here in Oklahoma City as -6 for those months that we are not using DST and -5 when we observe DST.

    I think I understand the relationship of our local time with respect to Universal Time Coordinated.

    However, I am trying to understand the information provided on a link which is located as follows:  http://time.unitarium.com/utc/

    Particularly confusing to me is the information presented there located immediately below the two clocks showing “UTC time” and “My Time,” there it states: 

    ·Time difference between your local time and UTC is: -5 hour(s) (-300 minutes).”  I seem to understand the “-5;” but, I am confused by the statement, “(-300 minutes).”  To me it seems that it would be sufficient to say that my time differs from UTC time by -5 hours as long as we are observing DST.  Why does the site say “ -300 minutes ?”     [The algarthym seems to acknowledge that Oklahoma City is recognized with a zone description of -6 for those months we are not observing DST; and likewise, for those months when we observe DST our zone time is -5].    But what is the significance of the -300 minutes ?

     

    Furthermore, there are three (3) hyperlinks located immediately below the statement which reads:

    "Time difference between your local time and UTC is: -5 hour(s) (-300 minutes).”

    When I click the hyperlink “Noon UTC,” it references my time to be 19:00 or 7PM when it is noon at Greenwich; which makes no sense to me.  

    What is the explanation for that which appears to be an incorrect statement?  My guess is that the "Noon UTC" hyperlinked algorithm sees that my longitude places me at a time zone of -7; and, that same algorithm also does not recognize our observation of DST here in Oklahoma City.  This explanation, if correct, would explain the seven (7) hour difference rather than the correct difference which is -5 hours.   The other two hyperlinks seem to make similar "errors." ???

     

    I do hope you are able to access the link: http://time.unitarium.com/utc/.  And I hope you are able to make sense of that which is being reported there as it is a little confusing to me.  While these concepts are not new to me I am not confidently fluent in there precise applications; there may be glaring errors in my logic; hence, the reason for my questions.     

     

    Steve

    OCBC

       
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