Garmin GPSMAP 640, Руководство пользователя

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GPSMAP 640 Owner’s Manual
Marine Mode: Using XM WX Weather and Audio
Understanding Surface Winds
Wind barbs indicate from which direction the wind is coming. The
wind barb is a circle with a tail. Wind speed is indicated by the
different combinations of flags that are attached to the tail.
Calm
5 knots
10 knots
15 knots
20 knots
50 knots
Wind Direction
Understanding Wave Height
The Wave Height feature shows wave heights. The wave heights
for an area are shown by color intensities.
Understanding Wave Period
The Wave Period feature provides the time (in seconds) between
successive waves.
Understanding Wave Direction
The Wave Direction feature shows the direction in which a wave is
moving, as indicated by the direction of red arrows.
Viewing Fishing Information
The Fishing view contains current water temperatures, surface
pressure conditions, and fishing forecasts.
Fish Forecasting
Understanding Surface Pressure
This feature shows pressure isobars and pressure centers. The
isobars connect points of equal pressure. Pressure readings can help
determine weather and wind conditions in an area. High-pressure
areas are generally associated with fair weather. Low-pressure
areas are generally associated with clouds and the chance of
precipitation. Isobars packed closely together show a strong-
pressure gradient. Strong-pressure gradients are associated with
areas of stronger winds.
Pressure units are shown in millibars (mbar), inches of mercury
(inHg), and hectopascals (hPa).