Moon and Tide Graph Settings
From G-Shock Wiki | casio watch resources
UTC Differential and Lunitidal Interval Table
Sjors' Guide to Programming a G-Shock Tide Graph
Sjors posted this great guide that goes over all the basics - http://forums.watchuseek.com/showthread.php?t=166281
Super jazezd about getting that know-how.
How do I find GMT differential, longitude, and latitude for my area?
The GMT differential depends on the time zone where you live, along with the status of Daylight Saving Time. For example, in the Eastern Time zone, the GMT differential would be -5 during standard time, or -4 during Daylight Saving Time. An atlas should give information on longitude and latitude for your area.
- You can also check with a Web site that provides maps, as they may also have longitude and latitude information. Here is one site that offers GMT differential, longitude, and latitude for many US locations:
- http://www.timeanddate.com/worldclock/ - Click the nearest city and look around for moon data for your area.
How do I find the Lunitidal Interval?
Lunitidal interval is the difference between moon up and the high tide immediately following moon up. Moon up is when the moon is directly over the person's longitude, not when it rises. Under ideal circumstances, the high tide and moon up time would be the same. Friction and the ocean floor cause the ocean to move at a different rate in different areas. Adjusting for this difference will give you a more accurate tide reading. You may find the following Web page to be helpful for finding the lunitidal interval:
You can also calculate lunitidal interval by going to:
Use Form A, and change type of table to moonrise/ moonset. Select state, and enter city for the tide you want to calculate. Or find some other way to find what the latitude and longitude is and when the moonrise and moonset. Halfway between these times would be the moon up.
Next, find the tide times for that day. These are usually in most newspapers that have a coastline, a local marina, or from the following site:
The lunitidal interval is the difference from moon up until the first high tide after moon up*.
During DST, the tide time may be 1 hour off. Add 1 hour to the lunitidal interval.
- The term "moon up" used by Casio does not mean moon rise, but the highest point of the moon when it is standing in the South.
Tidal Information for Locations in the US
Tidal Information for Locations in the UK
- http://www.pol.ac.uk/ntslf/sharing_knowledge.php - This site has tables of tide and moon information for different area in the United Kingdom.