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赤道 : 静风 : 方位 : 危险半圆 / 可航半圆: 赤道无风带: 副热带无风带: 向海风和向陆风 季风: 辐射雾 : 平流雾 : 蒸汽雾 : 锋面雾 : equator calm bearing dangerous semicircle, navigable semicircle doldrums.

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Presentation on theme: "赤道 : 静风 : 方位 : 危险半圆 / 可航半圆: 赤道无风带: 副热带无风带: 向海风和向陆风 季风: 辐射雾 : 平流雾 : 蒸汽雾 : 锋面雾 : equator calm bearing dangerous semicircle, navigable semicircle doldrums."— Presentation transcript:

1 赤道 : 静风 : 方位 : 危险半圆 / 可航半圆: 赤道无风带: 副热带无风带: 向海风和向陆风 季风: 辐射雾 : 平流雾 : 蒸汽雾 : 锋面雾 : equator calm bearing dangerous semicircle, navigable semicircle doldrums horse latitudes land and sea breeze monsoon radiation fog advection fog steam fog frontal fog A revision of the key words and expressions covered in the previous lesson.

2 Answer the following questions. What is the breeding place of the most violent storms? The dodrums How does the wind blow in a tropical cyclone in the northern hemisphere? It blows in a counterclockwise direction. What is the typical phenomenon in the center of a storm? It is 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 What is the typical weather before and upon the arrival of the hurricane? 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. Upon the approach of a hurricane, cirrostratus clouds replace the common at sunrise and sunset. The barometer continues to fall and at times is unsteady. Clouds darken and cover the entire sky. Wind increases and heavy seas develop.

3 Passage Three Clouds Vocabulary study condensation [kCnden5seiFEn] n. 液化,货仓凝水 water vapor 水汽 classification [7klAsifi5keiFEn] n. 分类,分级 adopt [E5dCpt] vt. 采纳 mean [mi:n] adj. 平均的 cirrus [5sirEs] n. 卷云 cirrocumulus [9sIrEJ5kjU:mjJlEs] n. 卷积云 cirrostratus [5sirEu5strB:tEs] n. 卷层云 sheet [Fi:t] n. (一)片,(一)张,薄片 altocumulus [5AltEu5kju:mjulEs] n. 高积云 wool [wul] n. 羊毛 altostratus [5AltEu5streitEs] n. 高层云 medium [5mi:djEm] adj. 中等的 uniform [5ju:nifC:m] adj. 统一的,相同的,一致的 layer [5leiE] n. 层 cloud layer 云层 condensation [kCnden5seiFEn] n. 液化,货仓凝水 water vapor 水汽 classification [7klAsifi5keiFEn] n. 分类,分级 adopt [E5dCpt] vt. 采纳 mean [mi:n] adj. 平均的 cirrus [5sirEs] n. 卷云 cirrocumulus [9sIrEJ5kjU:mjJlEs] n. 卷积云 cirrostratus [5sirEu5strB:tEs] n. 卷层云 sheet [Fi:t] n. (一)片,(一)张,薄片 altocumulus [5AltEu5kju:mjulEs] n. 高积云 wool [wul] n. 羊毛 altostratus [5AltEu5streitEs] n. 高层云 medium [5mi:djEm] adj. 中等的 uniform [5ju:nifC:m] adj. 统一的,相同的,一致的 layer [5leiE] n. 层 cloud layer 云层

4 cumulus [5kju:mjulEs] n. 积云 cumulonimbus [5kju:mjulEu5nimbEs] n. 积雨云 tip [tip] n. 尖端,梢 nimbostratus [5nimbEu5streitEs, -5strAtEs] n. 雨 层云,乱层云 stratocumulus [7strAtEu5kju:mjulEs] n. 层积云 globular [5^lCbjulE] adj. 球状的 upcurrent [5Qp9kQrEnt] n. 上升气流 updraft [ 5QpdrB:ft ] n. 上升气流 turbulent [5tE:bjulEnt] adj. 狂暴的,吵闹的 stratus [5streitEs] n. 层云 transparent [trAns5pZErEnt] adj. 透明的 cumulus [5kju:mjulEs] n. 积云 puffy [ 5pQfi ] adj. 膨胀的 detach [ di5tAtF ] vt. 分开,分离 buildup [ bildQp ] n. 组合,集结,形成 towering [ 5tauEriN ] adj. 高耸的 veil [ veil ] vi. 蒙上面纱,遮蔽 hail [ heil ] n. 冰雹

5 根据词缀和词根记单词: Tip: cirro- 卷 cumulo- 积 strato- 层 nimbo- 雨 alto- 高 cirrus 卷云 cumulus 积云 stratus 层云 nimbus 雨云 stratocumulus 层积云 Cirrocumulus 卷积云 Cirrostratus 卷层云 Cumulonimbus 积雨云 Altocumulus 高积云 Altostratus 高层云 Nimbostratus 雨层云

6 Clouds have names that come from Latin (an ancient Roman language). An English naturalist Luke Howard, in 1803, developed a classification system based on the following four main cloud types: · Cumulus: this is Latin for 'heap'. So it describes a puffy cloud. · Cirrus: this is Latin for 'curl of hair'. It describes a wispy cloud. · Stratus: this is Latin for 'layer'. It describes a sheet-like cloud. · Nimbus: this is Latin for 'violent rain'. It describes a rain cloud. Wispy.adj. 象小束状的, 纤细的,

7 Other clouds could be described by combining the basic types. For example, nimbostratus is a rain cloud that occurs in layers. The cumulonimbus, which forms Mr. Cloudbank's body is a rain cloud with well-defined upright development going straight up. Cirrostratus is cirrus occurring as a sheet-like cloud. Stratocumulus is a layer cloud with some cumulus features. There are ten principal cloud forms, which are divided into four primary cloud groups: 1. High clouds - cirrus, cirrostratus, cirrocumulus 2. Middle clouds - altostratus, altocumulus 3. Low clouds - nimbostratus, stratocumulus, stratus 4. Clouds with vertical development - cumulus, cumulonimbus

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11 Clouds The high-cloud family : Cirrus (Ci): Thin featherlike clouds. Indication – Cirrus clouds often indicate the direction in which a storm is located. When these clouds are scattered, they will only indicate that bad weather is a great distance away. Cirrocumulus (Cc): Regular groupings of small white rounded masses. Indication – Cirrocumulus clouds are an indication that storm is probably approaching. Cirrostratus (Cs): Very thin, high sheet cloud, darker than cirrus. Indication – The appearance of cirrostratus clouds is a good indication of rain due to the approaching of a warm front or occluded front.

12 The middle-cloud family: Altocumulus (Ac): Clouds that looks like the wool on the back of a sheep. Indication – When altocumulus clouds are followed by cirrocumulus, a thunderstorm is nearing. Altostratus (As): Medium high, uniform sheet cloud. Indication – Light rain or heavy snow may fall from a cloud layer that is definitely altostratus.

13 The low-cloud family: Nimbostratus (Ns): Low, shapeless, dark gray, rainy cloud layer. Indication – These are true rain clouds. These clouds are of little help in forecasting weather since the bad weather is already upon you. Stratocumulus (Sc): Globular masses or rolls. Indication – Underneath stratocumulus waves or rolls, strong winds occur. Under the thick parts, strong upcurrents rise. Above the cloud layer the air is smooth, but it is turbulent below and within the layer. These clouds do not, as a rule, produce anything but light rain or snow. 层积云:团块或条形云。层积云波状或条形云之下产生强风。在厚厚的云 层下,有强上升气流。云层之上气流平稳,但在云层之内和云层下气流湍 急。层积云一般只产生小雨或小雪。 Stratus (St): Low, uniform sheet cloud. Indication – Usually only drizzle is associated with stratus. When there is no precipitation, the stratus cloud form appears drier than other similar form, and it shows some contrasts and some lighter transparent parts. These clouds do not signify any potential danger.

14 Cumulus (Cu): Dense, dome-shaped, puffy-looking clouds. Indication – Strong updrafts exist under and with all cumulus formations. In fact, cumulus clouds, like other forms of vertically developed clouds, are caused by updrafts. These clouds, when detached and with little vertical buildup, are termed fair weather clouds. Cumulonimbus (Cb): Cauliflower, towering clouds with cirrus veils on top. Indication – Cumulonimbus clouds are generally associated with showers of rain or snow. They sometimes produce hail. They are also often associated with thunderstorms. Bad weather can be expected in the immediate area of these clouds.

15 Part Three Weather Routing Introduction Ship weather routing develops an optimum track for ocean voyages based on forecasts of weather, sea conditions, and a ship’s individual characteristics for a particular transit. Within specified limits of weather and sea conditions, the term optimum is used to mean maximum safety and crew comfort, minimum fuel consumption, minimum time underway, or any desired combination of these factors. The purpose of this part is to acquaint the mariner with the basic philosophy and procedures of ship weather routing as an aid to understanding the routing agency’s recommendations. The mariner’s first resources for route planning in relation to weather are the Pilot Chart Atlases and the Sailing Directions. These publications give climatic data, such as wave height frequencies and ice limits, for the major ocean basins of the world. They recommend specific routes based on probabilities, but not on specific conditions. 气象定线, 气象导航 最佳航线 [5trAnsit] n. 经过,通行 耗油率,燃料消耗(量) 定线机构 航线设计 引航图图集 [klai5m Atik] adj. 气候的 波高

16 Passage One Environmental Factors Vocabulary study surveillance [sE:5veilEns] n. 监视,监督 optimum routing 最佳航线定线 attain [E5tein] vt. 达到, 获得 optimize [5Cptimaiz] vt. 使最优化 head wind 逆风,顶风 following wind 送尾风,顺风 following sea 尾随浪,顺浪,顺流 high wind 疾风,强风 noticeable [5nEutisEbl] adj. 显而易见的,值得注意的 beam wind 横风 considerable [kEn5sidErEbl] adj. 相当大 ( 或多 ) 的,相当 可观的 propeller thrust 螺旋桨推力 head seas 顶头浪,船头浪,逆浪,迎浪(船头左右 15° 范围内) retard [ri5tB:d] vt. 延迟,阻,阻碍

17 feasible [5fi:zEbl] adj. 可行的,切实可行的 extensive [iks5tensiv] adj. 广大的,广阔的,广泛的 solely [5sEu(l)li] adv. 独自地,完全地 fatigue [fE5ti:^] n. 疲乏,疲劳 vigilance [5vidVilEns] n. 警戒,警惕 present [pri5zent] vt. 给,提出,呈现 evaluate [i5vAljueit] vt. 评价,估计 speed of advance 进速,前进速度,计划航速 variability [7vZEriE5biliti] n. 变化性,可变性 disrupt [dis5rQpt] vt. 使中断,使分裂,使瓦解,使陷于混乱, 破坏 El Nino 厄尔尼诺现象 twofold [5tu:fEJld] adj. 两部分的,双重的 floating ice 浮冰,漂冰 deck ice 船舶积冰,甲板积冰 pack ice 大块浮冰群,密集冰 contend [kEn5tend] vi. 对付,竞争,常与 with 搭配使用 associate [E5sEuFieit] vt. 伴随,常与 with 搭配使用 stability [stE5biliti] n. 稳性 El Niño is a charming name for the large-scale warming of surface water of the Pacific Ocean every 3-6 years that lasts a few months and dramatically affects weather and climate world wide.

18 Environmental Factors Wind: The effect of wind speed on ship performance is difficult to determine. In light winds (less than 20-knots), ships lose speed in head winds and gain speed slightly in following winds. For higher wind speeds, ship speed is reduced in both head and following winds. This is due to the increased wave action, which even in following seas results in increased drag from steering corrections, and indicates the importance of sea conditions in determining ship performance. In dealing with wind, it is also necessary to know the ship’s sailing area. High winds will have a greater adverse effect on a large, fully loaded container ship or car carrier than a fully loaded tanker of similar length. This effect is most noticeable when docking, but the effect of beam winds over several days at sea can also be considerable. 风速较大时,无论是顺风还是逆风船速都会降低,这是由于浪的作用在增 强。即使是顺浪也会抑制船舶操纵,这充分显示了海况在决定船舶操纵时 的重要性。

19 Wave Height: Wave height is the major factor affecting ship performance. Wave action is responsible for ship motions which reduce propeller thrust and cause increased drag from steering corrections. The relationship of ship speed to wave direction and height is similar to that of wind. Head seas reduce ship speed, while following seas increase ship speed slightly to a certain point, beyond which they retard it. In heavy seas, exact performance may be difficult to predict because of the adjustments to course and speed for ship handling and comfort. Although the effect of sea and swell is much greater than wind, it is difficult to separate the two in ship routing. 逆浪会降低船速,顺浪会在一定程度上轻微提高船速,如果顺浪过大也 会令船速降低。 在此, which 引导了非限制性定语从句,其先行词为 a certain point 。 They 在此指代前文中的 following seas ,而 it 指代的是 ship speed 。 beyond 意为超过。

20 Fog: Fog, while not directly affecting ship performance, should be avoided as much as feasible, in order to maintain normal speed in safe conditions. Extensive areas of fog during summertime can be avoided by selecting a lower latitude route than one based solely upon wind and seas. Although the route may be longer, transit time may be less due to not having to reduce speed in reduced visibility. In addition, crew fatigue due to increased watch keeping vigilance can be reduced. 在夏季,与完全基于风浪而做出的航线选择相比较,选择低纬度航线可以 更好地避免多雾地区。虽然航线可能更长,但由于不用在能见度不良的情 况下减速,通行时间可能会更短。除此以外,由于在值班中警惕性提高而 造成的船员疲劳也可以得到缓解。

21 Ocean Currents: Ocean currents do not present a significant routing problem, but they can be a determining factor in route selection and diversion. This is especially true when the points of departure and destination are at relatively low latitudes. The important considerations to be evaluated are the difference in distance between a great-circle route and a route selected for optimum current, with the expected increase in SOA (speed of advance) from the following current, and the decreased probability of a diversion for weather and seas at the lower latitude. Direction and speed of ocean currents are more predictable than wind and seas, but some variability can be expected. Major ocean currents can be disrupted for several days by very intense weather systems such as hurricanes and by global phenomena such as El Nino. (在利用洋流定线时)值得考虑的重要因素有大圆航线和为获得最佳洋流 而选择的航线间的距离差异,还有因为顺流使航速加快与在低纬度航行时, 天气和海浪因素使船舶改变航向的可能性减少的差异。

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23 Ice: The problem of ice is twofold: floating ice (icebergs) and deck ice. If possible, areas of icebergs or pack ice should be avoided because of the difficulty of detection and the potential for collision. Deck ice may be more difficult to contend with from a ship routing point of view because it is caused by freezing weather associated with a large weather system. While mostly a nuisance factor on large ships, it causes significant problems with the stability of small ships. Latitude: Generally, the higher the latitude of a route, even in the summer, the greater are the problems with the environment. Certain operations should benefit from seasonal planning as well as optimum routing. For example, towing operations north of about 40° latitude should be avoided in non-summer months if possible.

24 Homework Read the two passages and memorize the key words and expressions. Preview passage two and pay attention to the following points: initial route recommendation Adjustment of departure time. Diversion Adjustment of SOA Evasion A weather advisory


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