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spyboy
03-09-2008, 07:07 AM
When you're logging weather data, how do you account for daylight savings time? Is there just a 1 hour gap in the logs (based on time?)

Kirk

JimS
03-09-2008, 07:23 AM
That's a simple one...the OBS stays on standard time year round. No time change.

In fact, there are three clocks that the observers get used too. Standard (the time that the observatory observes), Daylight (the time the rest of the summit observes), and ZULU (Greenwich, the time that the rest of the meteorological world observes). You get used to it...

The observers slide shifts slightly. In the comments today, Mike F talks of now waking up at 4AM to do the work that usually was done at 5AM. This is to make sure that the radio shows in the morning are all done by the same people on the same routine, but the clocks dont change.

Bill O
03-09-2008, 08:28 AM
If you think about it, the Obs wouldn't miss any data if they set their clocks ahead. The observer would go out at 12:55am and get the data. They move the clocks at 1:00am and the next observation is at 2:55am. You didn't miss an ob, you just changed the time.

The reason they stay on EST or GMT is not about missing data, its about consistency in the records. Universal time is a constant, DST is arbitrary.

bikehikeskifish
03-09-2008, 10:09 AM
Being a software engineer, and having written much software that records time series data, the rule is always to record UTC and the value. When graphing, displaying or reporting, you can easily convert the UTC record from the database into a local time which includes the DST adjustment as necessary. So, today's 24-hour window includes 23 hours. When we "fall back" the 24-hour window would include 25 hours.

Tim

Mike D
03-21-2008, 10:13 PM
Universal time is arbitrary, DST is inconsistent.

I'm splitting hairs, yes, but I think arbitrariness is okay for science. Inconsistency is not. Examples of arbitrariness: the length of a meter, the number of seconds in a minute, the diameter of a precip can. These measures produce good science when applied consistently.

Taking 23 observations in one day and 25 another day is just wacky from a scientific perspective.


Universal time is a constant, DST is arbitrary.

Mike D
03-21-2008, 10:19 PM
Unix time (http://en.wikipedia.org/wiki/Unix_time) is the only way to go. Why would you say "It's Friday, March 21st" when you could just say "1206152257". Of course, if you'd rather do everything the hard way, there are X's of M's of ways to represent numbers.


Being a software engineer, and having written much software that records time series data, the rule is always to record UTC and the value. When graphing, displaying or reporting, you can easily convert the UTC record from the database into a local time which includes the DST adjustment as necessary. So, today's 24-hour window includes 23 hours. When we "fall back" the 24-hour window would include 25 hours.

Tim

mtruman
03-22-2008, 08:06 AM
Unix time (http://en.wikipedia.org/wiki/Unix_time) is the only way to go. Why would you say "It's Friday, March 21st" when you could just say "1206152257". Of course, if you'd rather do everything the hard way, there are X's of M's of ways to represent numbers.

It's definitely the only way to go - as long as you can deal with the fact that the big bang happened in 1970 :rolleyes:

Brad
03-22-2008, 08:39 AM
It's definitely the only way to go - as long as you can deal with the fact that the big bang happened in 1970 :rolleyes:
I had heard the big bang was coming this summer when Steve is up on the summit cooking.

Charlie
03-22-2008, 10:08 AM
I had heard the big bang was coming this summer when Steve is up on the summit cooking.


it better not go bang until after we summit :D :D