2 Flashcards
Common unit of measurement for atmospheric pressure
Inches
Series of brief showers accompanied by strong, shifting winds may occur along some distance ahead of a
Cold front
Fog produced by warm moist air over a cold surface
Advection fog
Accurate barometer check, check
Against radio or National Weather Service reports of the immediate vicinity
Cloud of marked vertical development (often anvil shaped)
Cumulonimbus
Buoys which ONLY mark the left or right side of the channel will NOT exhibit which light characteristic?
composite group flashing
Nav marks used for info or regulatory purposes are
White w orange geometric shapes
Buoy fitted w racon will appear on PPI as
Starting with a dash and extending radially outward from target
How are colored sectors of lights listed in the Light List
True bearings as observed from ship toward the light
Publication to check for Pugent Sound weather conditions
Coast Pilot
In some parts of the world there is a slight fall in tide during the middle of the high water period The effect is to create a longer period of stand at higher water This special feature is called a
Double high water
Class of tide that prevails in the greatest # of important harbors on the Atlantic Coast is
Semidiurnal
Vessel goes aground in soft mud. You’d have the best chance of refloating on next tide if grounded at
Low water spring
Definition of height of tide
The vertical distance from the tidal datum to the level of the water at any time
In a river subject to tidal currents, the best time to dock a ship without tugs is
At slack water
Slack water occur when there is
Little or no horizontal motion of water
Current encountered on direct passage from London, England to Cape Town, South Africa?
Benguela current
Current similar to the Gulf Stream
Kuroshio
Position which includes effects of wind and current
Estimated position
Most useful factor in predicting weather
The rate an direction of change of barometric readings
Scales on aneroid barometers are usually graduated in inches of mercury in the general range of
28 to 31 inches
What corrections must be applied to an aneroid barometer ?
Instrument error and height error
You should read the scale of aneroid barometer with eye
Directly in front of the pointer
Barometric pressure reading 29.92 inches of mercury is equivalent to
1013.25 millibars
