Article by Capt. Steve Katz
Timing is Everything!
Congratulations to all participants in this year’s White Marlin Open. The challenge of running offshore for consecutive days in all weather conditions is a lot of work for the crew and catching a prize-winning fish is even more difficult. We wish all crew and anglers good luck in all the upcoming tournaments.
Let’s review a popular topic during fishing tournaments -
Time of day
While many fishing crew may not wear a watch while fishing, keeping track of the correct time is even more critical during a tournament. With so many electronic gadgets supplying the time, we expect the time we see to be correct and synchronized between all devices and the tournament organizers. A marine Chartplotter or GPS, as with most modern timekeeping devices, needs to be properly programmed to your location for the proper time zone and daylight savings time if applicable. Many of us on a boat have come to rely on the time on the chartplotter or related device for the proper “official” time.
How does a GPS chartplotter know the correct time?
These chartplotters receive the time from the GPS satellites. In addition to longitude, latitude, and altitude, the Global Positioning System (GPS) provides a critical fourth dimension – time. Each GPS satellite contains multiple atomic clocks that contribute very precise time data to the GPS signals. GPS receivers decode these signals to the UTC standard and effectively synchronize each GPS receiver to the world’s atomic clocks. This enables users to determine the exact time to within 100 billionths of a second, without the cost of owning and operating atomic clocks.
The manufacturers of these GPS receivers generally automate the device’s time settings, allowing the time to be automatically adjusted based on your GPS location, just like a smartphone. Seems like a good idea, right? Well, many of the devices may be too smart; they know when your boat moves into a different time zone or time of year and even when it has exceeded the coastal 12-mile territorial waters of the USA. Once beyond the 12-mile coastal limit, the Chartplotter often automatically eliminates the daylight savings time (subtracting one hour in the summer) on the way to the distant fishing grounds and then adding back that hour on the return trip to the dock, at that same 12 mile territorial water limit. If your system is not set-up properly, your GPS time while offshore may be an hour different from the official time back at the dock!
The best way to deal with this issue and synchronize the vessel's time to the same time zone at port is to manually configure the time zone (or offset) of your GPS display systems. Often, the time of day menu on the chartplotter has a setting to adjust the display format and offset adjustment from UTC time reference. Keeping the same time at sea and at port will also allow your calculated ETA to be correct.
Here in Maryland during the summer, the time zone is -4 (minus 4 hours) from UTC.
Popular Garmin chartplotter devices generally default to an automatic time zone setting and need to be adjusted to a manual time zone configuration to eliminate the 12 mile offshore time change. The steps below are for the most popular current Garmin devices, other brands may be similar.
Start from the Home screen
Select Configure/Settings
Select Preferences
Select Units
Select Time
Select Time Zone
Select Custom, then change to -4 for summer season on the east [email protected].
GMT or UTC?
Many of us once referenced time based on Greenwich Mean Time (GMT). GMT is a time zone in England that also happens to be the same as UTC.
The Universal Time Coordinated (UTC) is an international standard referenced around the world. UTC is an atomic timescale; it usually has 86,400 seconds per day but is kept within 0.9 seconds of the mean solar time as by the introduction of occasional leap seconds. If you are curious, there are currently 37 worldwide time zones, with some zones 30- or 45-minute intervals as compared to the traditional one-hour differentials based on 1 hour per 15 degrees longitude.
If you are using a digital video camera or still camera (especially in tournaments) be sure you check and set the device's time, so the image's timestamp is correct with the time zone and season.
Setting your ships clocks and devices to the correct time will allow you to be sure you start and stop fishing at the correct time, fill out the catch reports properly and have the correct estimated time of arrival (ETA) for your trip.
Until next time...
Stay Grounded
