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3.5.3.1.3 Satellite
Some vessels may have satellite service for phone, email and fax. Ask the captain for specific
instructions on your vessel.
3.5.3.2 Routine communication with the SOP
Observers will be expected to communicate with the SOP on a regular basis. Each country
has its own requirements for the frequency of contact and what you need to report (Appendix
1). The observer will be able to receive/send radio calls using the radio of the vessel.
Remember, if you are using the radio, you may need to communicate some of the fishing
information using codes provided by the SOP. Alternatively, the observers can send SMS
from their cell phones when they are within service range.
3.5.3.3 Emergency communications
In case of a medical emergency, contact the SOP as soon as possible. Appendix 2 lists the
contact names / numbers of SOP staff.
3.5.4 Navigation
Navigation is the act of determining a vessel’s position, ascertaining speed and directing the
course of a ship by using charts and electronic aids.
3.5.4.1 Geographic structure of the earth
The earth is almost spherical in shape with an axis of rotation around an imaginary line
through the north and south poles. The equator (0º) is a circle around the earth’s surface that
is perpendicular to the rotational axis and it splits the earth into two sections – the northern
and southern hemispheres (Figure 3-3). Lines of latitude, or parallels, run horizontally
circling the globe like a belt. The poles at the furthest north and south locations are at 90º.
Lines of longitude, or meridians, run vertically splitting the globe into two sections – east and
west. There are 180º of longitude in each direction. When the two systems are combined,
you get coordinates that define specific places on the planet.
A position can be expressed in degrees of latitude and longitude. Degrees can be split into
smaller units called minutes of arc (these minutes have nothing to do with time). Each degree
consists of 60 minutes of arc. Subunits of minutes are in seconds (60 seconds =1 minute).
GPS readings can be in multiple formats (e.g., degrees, minutes, seconds- N 03°25’30” or
degrees, minutes and 10ths of minutes- N 03°25.5’ or decimal degrees- N 03.425°). Be aware
of the format when recording position data from the vessel’s GPS unit.
3.5.4.2 Nautical measurements
A degree of latitude is equal to 60 nautical miles. One nautical mile equals 1,852 meters.
Because the meridians of longitude get closer to one another as they approach the poles,
distance between degrees of longitude decreases as you approach the poles. Vessel speed is
typically measured in knots (1 knot = 1 nautical mile per hour). Commercial fishing vessels
rarely travel at more than 10 knots (18 km/hr).
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