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    Re: Pilot charts
    From: Andrés Ruiz
    Date: 2008 Apr 16, 08:11 +0200

    Dear Gary,
    Such strong currents no exist. 30 is not the speed, is the percentage of occurrence in current direction.
    Reading Current Roses:
    Like the wind rose, the current rose graphically, (attached pic), depicts 
    numerous current characteristics such as percentage occurrence of current in 
    eight compass directions, and speed in knots of the current.  The length of 
    the 8 lines radiating out from the circle indicates the percent occurrence of 
    current FLOWING TOWARDS each compass direction.  The longer the line the 
    higher the occurrence in that direction.  If the length of the line exceeds 
    the area available to display it (approximately 30 percent), the actual 
    percentage is displayed.  The number of feathers on the line indicates the 
    speed in knots of the current in that direction with each feather 
    representing 0.2 knots.
    -----Mensaje original-----
    De: NavList@fer3.com [mailto:NavList@fer3.com] En nombre de Gary J. LaPook
    Enviado el: miércoles, 16 de abril de 2008 1:43
    Para: NavList@fer3.com
    Asunto: [NavList 4842] Re: Pilot charts
    glapook@pacbell.net wrote:
    I have attached a portion of the January Pilot Chart of the South 
    Pacific Ocean published by the Defense Mapping Agency. Until I looked at 
    this chart I had no idea that currents in the South Pacific could be so 
    strong. The green arrows show the current  direction and speed in knots. 
    For example, the current shown passing the southern end of New Zealand 
    is 10 to 20 knots! And in the Gilberts it shows up to 30 knots! How do 
    ships manage to maneuver against such strong currents?
    Navigation List archive: www.fer3.com/arc
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