航海英语航海气象章节练习(2018.01.09)

单项选择题
The belt of light and variable winds between the westerly wind belt and the northeast trade winds is called the（）.
A.subtropical high pressure belt
B.intertropical convergence zone
C.doldrum belt
D.polar frontal zone
单项选择题
Pressure gradient is a measure of（）.
A.a high-pressure area
B.pressure difference over horizontal distance
C.pressure difference over time
D.vertical pressure variation
单项选择题
A tide is called diurnal when（）.
A.only one high and one low water occur during a lunar day
B.the high tide is higher and the low tide is lower than usual
C.the high tide and low tide are exactly six hours apart
D.two high tides occur during a lunar day
单项选择题
When experiencing heavy winds，you should reef sails to（）.
A.bring the sails parallel to the wind
B.reduce sail area exposed to the wind
C.allow the sails to catch more wind
D.remove all tension on the main and jib sheets
单项选择题
Navigational warnings and weather bulletins for shipping（）from Singapore Radio.
A.broadcast
B.broadcasted
C.are broadcast
D.are broadcasted
单项选择题
In mid-ocean，the characteristics of a wave are determined by three factors. What is NOT one of these factors?（）.
A.Effect of the moon's gravity
B.Fetch
C.Wind velocity
D.Length of time a wind has been blowing
单项选择题
A weather map is a synoptic data because it（）.
A.summarizes a great deal of information
B.can be interpreted accurately
C.appears daily
D.is prepared by the Weather Bureau
单项选择题
The direction of prevailing winds in the Northern hemisphere is caused by the（）.
A.Magnetic field at the North Pole
B.Gulf Stream
C.Earth's rotation
D.Arctic cold fronts
单项选择题
Especially in adverse weather，risk of collision with an offshore supply vessel increases when the vessel is moored to what side of the unit?（）.
A.Upwind
B.Downwind
C.Crosswind
D.Downcurrent
单项选择题
In the doldrums you can expect（）.
A.steady，constant winds
B.frequent rain showers and thunderstorms
C.steep pressure gradients
D.low relative humidity