Review the key words and phrases learned previously

1
Review the key words and phrases learned
previously
?? ?? ?? ???? ?? ?? ?? ??? ??? ???? ??
??
Front
Air mass
Warm sector
Pressure system
Occlusion
Depression low
Anticyclone high
Trough
Ridge
Pressure gradient
Fill
Deepen
2
Try to answer the following questions
1. What is the difference between backing and
veering?
Backing means a change in the direction of wind
in an anti-clockwise direction, while veering,
clockwise direction.
2. Under what condition will occlusion happen?
The cold front moves faster than the warm front
and gradually overtakes it, causing the warm to
be lifted up from the surface. When this happens
the depression is said to be occluded, known as
occlusion.
3. What type of weather will a steep pressure
gradient and a weak gradient respectively
indicate?
Weather in strong or steep pressure gradients is
normally subject to sudden changes with varying
wind force and direction while weak gradient
indicates that the weather changes are gradual
and predictable.
4. What type of barometer is most commonly used
aboard ship?
Aneroid barometer.
3
Radio Weather Messages
Warnings
Synopses
Forecasts
direction and speed of wind, the weather,
temperature, visibility and state of the sky and
sea over a period 12 or 24 hours
Gale Warnings 8-9
Storm Warnings 10-11
Hurricane Warnings 12 or above
General Situation, Synoptic Situation, Synopsis,
Summary
pressure systems and fronts, their direction,
speed of movement
pressure systems and fronts, their direction,
speed of movement Low, high, front
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• ????
• ????
• ????
• ???
• ??
• ?
• ?
• ????
• ????
• ???
• ??/??/??
• ?????/??/??

Gale Warning
Storm Warning
Hurricane Warning
Imminent
Synopsis, General situation, Synoptic situation,
Summary
Overcast
Clear, fine, fair
Scattered shower
Isolated shower
thunderstorm
slight, moderate, rough
poor, moderate, good
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Vocabulary study
imminent 5iminEnt adj. ???(???????4????) soon
sun adj. ??(?4?????12????) later 5leitE
adj. ??(?12????) synopsis si5nCpsis n. (pl.
synopses) ?? barometric 7bArEu5metrik adj.
???,??? tendency 5tendEnsi n. ?? summary
5sQmEri n. ??,??,?? issue 5isju vt. ??
issuance 5iFu()Ens n. persist pE()5sist
vi. ?? swell swel n. ? patch pAtF n.
?,??? rain patches ?????? on behalf of
?? coastguard n. ????? UTC universal coordinated
time ????? valid 5vAlid adj. ??? tend tend
vi. ?? outlook 5autluk n. ????(??24???????)
persist in the study of English ?????? On the top
of very high montains snow persists thronghout
the year. ????, ???????
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e east ? w west
? s south ?
n north ? ely easterly ?? sly
southerly ?? wly westerly ?? nly
northerly ?? ne northeast ??
nw northwest ?? se southeast ??
sw southwest ?? ene east-north-east ??? wsw
west-south-west ??? nm nautical mile ??
km kilometer ?? ml mile ??
mb millibar ?? kt
knot ? vis visibility
??? temp temperature ?? C
degrees Celsius ??? vrb variable ????
slw slow ??? frq frequent ???
stnr stationary ??? qstnr quasi-stationary ???
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tempo temporary ??? press pressure ?? baro
barometer ??? deg degree ? ft
foot/feet ?? mod moderate
?? max maximum ?? min minimum
?? sit situation ?? wx
weather ?? gmtGreenwich Mean Time ??? z
zulu time ??? wrng warnings ?? msg
message ?? obsy observatory
??? pd period ?? para
paragraph ? cma comma ?? pt
point ? wkn weaken ?? lgt light ?
isol isolated ??? sct
scattered ??? ocnl occasional ??
cld cloudy ?? dz drizzle ??? ts
thunderstorm ??? nc no change ????
8
Beaufort wind scale
0 Calm ?? lt 1 Flat.
1 Light air ?? 1-2 Ripples without crests.
2 Light breeze ?? 3-6 Small wavelets. Crests of glassy appearance, not breaking horses.
3 Gentle breeze ?? 7-10 Large wavelets. Crests begin to break scattered whitecaps.
4 Moderate breeze ?? 11-15 Small waves with breaking crests. Fairly frequent white horses.
5 Fresh breeze ?? 16-20 Moderate waves of some length. Many white horses. Small amounts of spray.
6 Strong breeze ?? 21-26 Long waves begin to form. White foam crests are very frequent. Some airborne spray is present.
ripple 5ripl n. ??,??,??
wavelet 5weivlit n. ??,??,??
crest krest n. ??
whitecap 5(h)waitkAp n.(??)???,???
white horse ???,???
spray sprei n. ??,??
foam fEum n. ??, ??
airborne 5ZEbCn adj. ???,?????
9
Beaufort wind scale
streak strik n. ??,??
7 Near gale ?? 27-33 Sea heaps up. Some foam from breaking waves is blown into streaks along wind direction. Moderate amounts of airborne spray.
8 Gale ?? 34-40 Moderately high waves with breaking crests forming spindrift. Well-marked streaks of foam are blown along wind direction. Considerable airborne spray.
9 Strong gale ?? 41-47 High waves whose crests sometimes roll over. Dense foam is blown along wind direction. Large amounts of airborne spray may begin to reduce visibility.
10 Storm ?? 48-55 Very high waves with overhanging crests. Large patches of foam from wave crests give the sea a white appearance. Considerable tumbling of waves with heavy impact. Large amounts of airborne spray reduce visibility.
11 Violent storm ?? 56-63 Exceptionally high waves. Very large patches of foam, driven before the wind, cover much of the sea surface. Very large amounts of airborne spray severely reduce visibility.
12 Hurricane ?? 64 Huge waves. Sea is completely white with foam and spray. Air is filled with driving spray, greatly reducing visibility.
spindrift 5spindrift n. ?????,??
overhang 5EuvE5hAN vi. ????, ??
tumbling 5tQmbliN n. ???,???
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Wave scale
furrow 5fQrEu vt. ?,?,??
3 Slight ?? 0.5 - 1.25 Waves rock buoys and small craft.
4 Moderate ?? 1.25 - 2.5 Sea becoming furrowed.
5 Rough ?? 2.5 - 4 Sea deeply furrowed.
6 Very rough ?? 4 - 6 Sea much disturbed with rollers having steep fronts.
7 High ?? 6 - 9 Sea much disturbed with rollers having steep fronts (damage to foreshore).
8 Very high ??/?? 9 - 14 Towering seas.
9 Phenomenal ??/???? Over 14 Precipitous seas (experienced only in cyclones).
precipitous pri5sipitEs adj. ???,???
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Visibility scale
0 Dense fog ?? 0-50m
1 Thick fog ?? 50-200m
2 Fog ? 200-500m
3 Moderate fog ?? 500-1000m
4 Thin fog or mist ?? 1-2kms
5 Vis. poor ????? 2-4kms
6 Vis. moderate ????? 4-10kms
7 Vis. good ???? 10-20kms
8 Vis. very good ????? 20-50kms
9 Vis. exceptional ?????? 50kms
???????????1 mile 1.852 km
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Part Two Marine Weather
Introduction
??,??
hju5miditi n. ??,??
Weather is the state of the earth's
atmosphere with respect to temperature, humidity,
precipitation, visibility, cloudiness, and other
factors. All weather may be traced to the effect
of the sun on the earth. Most changes in weather
involve large-scale horizontal motion of air.
Weather is of vital importance to the mariners.
The wind and state of the sea affect dead
reckoning and reduced visibility limits piloting.
The state of the atmosphere affects electronic
navigation and radio communication. If the skies
are overcast, celestial observations are not
available and under certain conditions
refraction and dip are disturbed. When wind is
the primary motive power, knowledge of the areas
of favorable winds is of great importance. Modern
vessels are still affected considerably by wind
and sea.
????,???? The process of calculating ones
position, esp. at sea, by estimating the
direction and distance traveled rather than by
using landmarks, astronomical observations, or
electronic navigation methods ???????,????????????
?
treis vt. ??,??
?? ??
celestialsi5lestjEl, si5lestFEl adj. ???,???
ri5frAkFEn n. ??,??
dip n. ??? ?????????
kEn5sIdErEbElI adv. ???
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Passage One Tropical Cyclones
Vocabulary study

• equator i5kweitE n. ??
• baffle 5bAfl vt. ??, ?? baffling wind
  ????
• doldrums 5dCldrEmz n. ?????
• willy-willy 5wili5wili n. ???,(?????)?????
• baguio bBi5Eu n. ???(??????????)
• circular 5sEkjulE adj. ???,???
• elliptical i5liptikEl adj. ???
• whirling (h)wEliN adj. ???
• eddy 5edi n. ??, ??
• calm kBm n. ??
• horse latitudes ??????
• precede pri()5sid vt. ???, ??
• cirrus 5sirEs n. ??
• bearing 5bZEriN n. ??

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reliably ri5laiEbli adv. ??? distinct
dis5tiNkt adj. ???, ????? diurnal dai5Enl
adj. ???,???, ??? signify 5sinifai vt. ??,
?? cirrostratus 5sirEu5strBtEs n. ??? bank
bANk n. (?)? horizon hE5raizn n. ??? gusty
5Qsti adj. ??? portion 5pCFEn n.
??? semicircle 5semi5sEkl n. ??
dangerous semicircle ???? navigable 5nAviEbl
adj. ?????,??? navigable semicircle ???? add
to ?? subtract sEb5trAkt vt. ( from) ??,
? peak pik vt. ????? n. ??,??? statistical
stE5tistikEl adj. ???,???? encompass
in5kQmpEs vt. ??,??,??
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Tropical Cyclones
Near the equator lies a low-pressure belt
where winds are either light and variable or
nonexistent. There are frequent thunderstorms and
squalls. This belt of baffling winds and rain is
called the doldrums and is the breeding place of
the most violent of all storms tropical
cyclones. In the Atlantic, tropical cyclones
are known as hurricanes in the Pacific, as
typhoons in Australia, as willy-willies and in
the Philippines, as baguios. All are alike in
character. The use of the term "hurricane" will
apply to all of these systems. Hurricanes are
circular or elliptical whirling eddies of air up
to 400 miles in diameter. Wind speeds reach as
high as 150 or more knots near the center, but
decrease toward the edges. In the Northern
Hemisphere, the wind blows in a counterclockwise
direction in the Southern Hemisphere, it blows
in a clockwise direction. Typical of these storms
is a calm at the center or eye, which may be 5 to
40 miles in diameter. When the eye of a storm
passes over an area, wind that has been violent
decreases to a much lower speed and at times
becomes calm and precipitation stops. When the
eye has passed, the winds come from the opposite
direction.
?????????????????,????,???????????????????????????
,????????? ?????????
??????????????5?40???????????????,??????????????,?
?????????,????????,?????????????,?????????
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The actual cause of the formation of
hurricanes is unknown. Soon after they form, they
begin to move at speeds from 5 to 20 miles per
hour. In the Northern Hemisphere, they generally
follow a slightly curving path to the north and
west until reaching the horse latitudes. The
hurricanes then re-curve to the northeast, pick
up speed over the surface, become less violent,
and finally blow themselves out. In the Southern
Hemisphere, the general path of hurricanes is
first to the southwest and then they re-curve to
the southeast. The life of a hurricane is about
10 days. Hurricanes are usually preceded by a
day of good visibility. Temperature and pressure
are slightly higher than normal. Cirrus clouds
appear. Wind changes direction and increases in
force sea swells increase their period. At
night, the temperature is generally lower than
normal. During the summer and fall in the Gulf of
Mexico and the Caribbean Sea, the bearing of the
storm is reliably indicated by the direction from
which the swells come. In any other area this
sign is unreliable. .
????,?????????????????????????????,????????,??????
?????
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A vessel in the navigable semicircle would
probably be blown to a position behind the storm.
It is also clear that speed of the wind in the
right semicircle would be greater as the speed of
the storm over the surface would be added to the
speed of the wind. In the left semicircle, speed
of the storm would be subtracted from speed of
the wind therefore, wind and sea would be less
violent. In the Northern Atlantic Ocean, a
distinct hurricane season occurs from June 1 to
November 30, sharply peaking from late August
through September. The statistical peak of the
Atlantic hurricane season is 10 September. The
Northeast Pacific Ocean has a broader period of
activity, but in a similar time frame to the
Atlantic. The Northwest Pacific sees tropical
cyclones year-round, with a minimum in February
and March and a peak in early September. In the
North Indian basin, storms are most common from
April to December, with peaks in May and
November. In the Southern Hemisphere, the
tropical cyclone year begins on July 1 and runs
all year round and encompasses the tropical
cyclone seasons which run from November 1 until
the end of April with peaks in mid-February to
early March.
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Passage Two Prevailing Winds and Fogs
Vocabulary study
prevailing pri5veiliN adj. ???,
???,??? prevailing westerlies ????? expand
iks5pAnd vi. ??,?? contract 5kCntrAkt vt.
??,?? equatorial 7ekwE5tCriEl, ik- adj. ????,
??? polar 5pEulE adj. ???, ??? poleward
5pEJlwEd adj. ??(??)??,??? excess ik5ses,
5ekses n. ??,?? definite 5definit adj. ???,
??? extend iks5tend vi. ??,?? in the vicinity
of ??? shift Fift vi. ??,?? characterize
5kArIktEraIz vt. ????? trade wind
?? permanent 5pEmEnEnt adj. ???, ???
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duration djuE5reiFEn n. ????, ?? due dju
adj. ???? due west ?? land mass ??? land
breeze ???,?? sea breeze ???,??(????????) alternat
ing Cl5tEnitiN adj. ??? adjoining E5dVCiniN
adj. ??? penetrate 5penitreit vi.
??,??,?? onshore 5Cn5FC adv. ????,??? offshore
5C()fFC adv. ?????,???,??? monsoon mCn5sun
n. ?? torrential tC5renFEl adj. ???,??? suspend
sEs5pend vi. ?? radiation fog ??? advection fog
???,??? steam fog ??? evaporation i7vApE5reiFEn
n. ??(??) saturate 5sAtFEreit vt.,
vi.(?)?? frontal fog ???
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Prevailing Winds
Doldrums The low pressure belt extending around
the earth in the vicinity of the geographical
equator. They shift slightly north or south with
the seasons. They are characterized by light
winds, cloudiness, afternoon thunderstorms and
showers, and a depressing humidity.
???????????????????????,??????????????????????????
??????????????????
Trade winds The relatively permanent winds on
each side of the equatorial doldrums that blow
from the northeast in the Northern Hemisphere and
from the southeast in the Southern Hemisphere.
???????????????????????????,??????????????????,???
???,????,????,?????????
Horse latitudes These are zones of high
atmospheric pressure on the poleward side of each
trade wind where calms and variable winds
prevail. The conditions are unlike those in the
doldrums where the air is fresh and clear and
calms are not of long duration.
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Prevailing westerlies The prevailing westerly
winds (winds blowing from the west) are those on
the poleward sides of the horse latitudes.
Land and sea breeze The cause of land and sea
breezes is the alternating heating and cooling of
coastal land and sea areas. The land,
particularly in summer, is warmer than the sea by
day and cooler than the sea by night. Therefore,
there is a variation in atmospheric pressure over
adjoining land and sea areas. This causes a
system of littoral breezes which blow landward
during the day and seaward during the night.
These land and sea breezes usually penetrate to a
distance of about 30 miles onshore and offshore,
and extend to a height of a few hundred feet.
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Fog
Radiation fog Radiation fog occurs at night. It
only forms when the land cools which in turn,
cools the air above.
Advection fog Advection fog is the most
widespread type likely to be encountered at sea
and occurs when warm air flows over a cool
surface. Advection fog can form only in regions
where marked temperature contrasts exist within a
short distance of each other and only when the
wind blows from the warm area toward the cold
area.
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Steam fog Steam fog is a type of advection fog.
It occurs when cool air blows over a warm
surface. Evaporation from the warm surface easily
saturates the cool air, causing fog, which rises
from the surface like smoke.
Frontal fog Frontal fog occurs in the cold air
mass of a front. As warm rain falls into the cold
air, it evaporates, saturating the cool air and
causing the fog. Although the cool air already is
saturated, evaporation from the rain continues as
long as the temperature of the raindrops is
higher than the temperature of the air. Frontal
fogs are rarely caused by cold fronts because
they usually move so rapidly and have such narrow
bands of precipitation. Warm fronts, on the other
hand, cause deep and long-lasting fogs that are
considered the worst type to encounter.
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Homework

• Review the passages learned today and memorize
  the key words and expressions.
• Preview passage three and part three and pay
  attention to the following points

• How many types of clouds are there in those three
  different cloud families and what are they?
• What type of weather does each cloud indicate?
• Familiarize yourself with the basic knowledge of
  weather routing.