Sunday, March 20, 2011

Latitude

Fortunately for all of us this is going to be a very short blog entry.  I must say though that every time I have turned around during the past few months I have had multiple time zone updates for my Linux / Unix type systems.  Since Time Zone updates are buried deep in the bowels of major updates for Windows systems they were also in them. You just do not see them but they cause problems for Microsoft as well.  But lets start off with the effects of latitude by asking a question, who can benefit from DST?  Surprisingly, unless your latitude lies within the range of 30 degrees to 45 degrees latitude North or South you just cannot benefit.  Why?  Well, if you are closer to the equator you just don't have that much difference between the daylight hours between the summer and winter solstices.  What you are trying to take advantage of is the fact that there are more minutes of daylight in the summer than there are in the winter, but not too many more minutes. You get these differences because the Earth's axis of rotation isn't vertical in relation to the sun but on a slant.  If you go farther away than 45 degrees of latitude away from the equator the differences between summer and winter minutes get abnormally large.  In fact they are so large you have a perpetual night in winter and if you only sleep when the sun is down in summer you aren't going to get enough sleep unless all you need is two to three hours per day.  But if you are in Miami the differences between the two just aren't that great.  Here is a starter URL:

 Solstices

I am not going to go out and find a cross section of the links of the effects of latitude on the number of daylight hours because almost all of them are wrong.  Just rest assured that the number of daylight seconds in Anchorage during the summer solstice is much greater than they are in Miami. You don't believe me?  Then look at this Mathematician's way of looking at it (and he is probably wrong on most of it because he didn't grasp the most salient point - the actual amount of seconds for day and night at any given day of the year at various latitudes):

Math-Daylight-Time

Note when all of this is going on and when the person wrote it. It is very close to the 23 September, the fall equinox.  Guess what?  There isn't much difference between the number of daylight seconds at any given latitude for either the fall or spring equinox.  They are very close to 43,200 seconds for both daylight and night hours when you are at an equinox no matter what latitude you are at.  Where the differences are the greatest are when you are near the summer or winter solstices. Okay, isn't there really something that will show me why I got only 6 hours of sleep at the end of June in Tok Junction, Alaska?  Will it also show me I would have got almost my required ten to twelve hours of sleep down at Key West at that same time of year during the night?  Well, yes there is something that will show it and it is graphical:

Affects-Of-Latitude-On_Daylight

Thank you University of Nebraska at Lincoln!  You have it correct!  You get an A not only for having it correct but by giving people a visual way of seeing how latitude affects things.  It enables you to see that the time shifts far more the farther you go away from the equinox by latitude.  You can actually see all of this by for example selecting either March 20 or September 23 and then varying the latitude.  If there is a difference  it is so minute most people don't see it.  Now select the day that DST ended in the US for the year 2010: 7 November.  Drag the latitude control from the southern tip of Florida to the Great Lakes area.  In the Keys at about 24.5 degrees North latitude you will have about 11 hours of daylight.  But in Duluth Minnesota at about 46.8 degrees you will have less than 9.6 hours of daylight.  There is definitely a difference of time for the two latitudes and it gets more pronounced both the farther you are away from the equator in latitude and the farther you are away from the equinoxes / closer you are to the solstices.

Safety:
That leads to some problems.  Children in Key West may safely go to and from school on 5 November since they will probably have ample daylight between sun up and when they go to school.  But children in Duluth, Seattle, and other places will have difficulty because usually when they are traveling to school it is sometimes actually dark.  In addition to the danger they face, precious energy is wasted because they are getting up too early so lights are turned on, and temperatures are raised.  What this is leading to is that there is no one size fits all.  What is appropriate in Key West is not appropriate in Northern states or closer to the equator.  In fact it is so bad that in most of Alaska and Hawaii things are so bad that DST just doesn't make sense any more due to latitude.  But even for northern states in the 48 contiguous states of the US it also does not make sense.  In fact it is so bad that one thing that those time zone updates for Linux are indicating is that DST is going to come to an end sooner in the year 2011 than it did in 2010 in the Pacific time zone and other places.  I have a better solution.  Just shift the clock to the standard time this fall when they do that and leave it there.  Drop DST and just shift to doing things a little earlier if it makes sense for your given latitude and temperature conditions.  The reason Arizona doesn't do DST has gone on for 40 plus years now and it is very simple.  They shut down during the middle of the day during the summer because it is just too hot to do anything.  It is this kind of common sense thinking that needs to be done and to do it DST has to be brought to an end.  I don't want little children being killed in Duluth MN, Bismarck ND, Great Falls MT, or Seattle WA just because of an inflexible time system called DST.  It is time to send DST to the scrap heap and allow these people to decide regionally when it makes sense to starting doing things an hour later or maybe even splitting it up into two shifts of 30 minutes each.  By that I mean they would shift from a start time of 08:00 to 08:30, and then 09:00 a few weeks or month after that. That would be in the fall.  In late spring it could go the other way. But you don't have to shift the clock to do it.  All you need to is to change the start times to earilier in the spring and shift them back later in the fall. For some states like Tennessee (low change in latitude) it probably can be done by state.  For states like California it could be done by locale.  Crescent City is at about 41.45 degrees northern latitude, San Francisco is at 37.45, and San Diego is at 32.43.  If you start looking at those differences on that interactive graph provided by the University of Nebraska you should be able to see you may need something different in all of those locales. You may want to do the time shift eariler / later at each latitude or maybe no shift at all.  But you should do it without using DST!  I am committed to doing away with this stupid insane nonsense called DST once and for all.  It may have got started with the claims of saving energy with incandescent bulbs but I am not the only person that has swapped out incandescent for fluorescent which I did twenty years ago.  The biggest way to save energy is simple - use more insulation.  That and fluorescent bulbs reduce your electrical needs considerably.  The people in the Andalusian area of Spain have saved energy by having lots of cave dwellings.  They are much cooler in the summer and warmer in the winter and use much less energy.  That is the kind of thinking we need more of.

No comments:

Post a Comment