Warmingup、Pre-reading、Reading、Comprehending (4)

1、人教课标 高三 选修 9 Unit 2,Unit 2 Sailing the oceans,Indian Ocean,Pacific Ocean,Atlantic Ocean,Arctic Ocean,Question: How many oceans are there in the world?,Warming up,Ferdinand Magellan 费迪南德 麦哲伦,What is a navigator?,A navigator explores new routes across the sea.,Vasco da Gama 瓦斯科 达伽马,Christopher Columbu

2、s 克里斯托弗 哥伦布,What is the difference between a navigator and an explorer?,Navigator,sea,nautical instruments,find new islands or continents,A navigator explores the sea.,Explorer,land,use compass and landmarks,find new places within an already identified island or continent,An explorer discovers new p

3、laces on land.,Zheng He,Marco Polo,James Cook,Look at these famous people. Are they navigators or explorers? What do you know about them?,Zheng He 1371-1433,He led a large fleet to explore Southeast Asia, India and the Middle East in the Ming Dynasty. Altogether he made 7 voyages in the 15th century

4、. He travelled more than 50,000 km and visited 30 countries new to China and developed many trade links. He is considered one of the earliest naval explorers in Chinese history.,Marco Polo 1254-1324,He is the most famous westerner to travel the Silk Road and the only person to provide information ab

5、out China to the outside world. In 1271 he set out to reach the Mongol Empire and then China. In 1295, he arrived back in Europe. Three years later he was imprisoned by the Genoese. While in prison, he told the story,of his travels to a fellow prisoner who wrote his adventures down. When his book wa

6、s published it became a best-seller.,The Map of Marco Polos voyage,James Cook,1728-1779,James Cook was the greatest Britain navigator. Cook joined in the Royal Navy in 1755. In 1768 he was promoted and sent to the Pacific where he surveyed Tahiti, New Zealand, and Australia. On his famous second exp

7、edition (1772-1775) he explored Antarctica. In 1776 he undertook his third and final,voyage in which he explored the West Coast of North America and tried to locate a passage between the Atlantic and Pacific oceans. On this voyage he discovered the Hawaiian Islands, and sailed up the coast of North

8、America through the Bering Straits to the Arctic Ocean. On his return he was killed by Hawaiian islanders. He is regarded as one of the worlds greatest explores and navigators.,The four basic instruments for navigation: compass, astrolabe, sextant and nautical chart.,compass,astrolabe,sextant,nautic

9、al chart,Answer the questions.,1. How do you think seamen found their way before modern accurate methods of navigation were invented?,Kept close to the shore, used nature such as the sun, wind, birds, tide, etc, to help them, and used some of the instruments including a compass, astrolabe, etc.,2. W

10、hich do you think was easier to work out: latitude or longitude?,Latitude, because it was used to measure how far you had traveled from land on a straight line. It was discovered a long time before longitude.,3. Can you identify these early navigational instruments seamen used and explain how they a

11、re used?,1) compass (in ancient China) 2) astrolabe 3) sextant 4) sea / nautical / marine chart,4. Which ones do you think are still used today?,Sea charts are still used today.,Sailing the oceans,Read about what navigation was like before modern instruments were used.,Scanning,How did seamen explor

12、e the oceans before latitude and longitude made it possible to plot a ships position?,Page 1,Using nature,Keeping alongside the coastline Using celestial bodies Using wildlife Using the weather Using the sea,Using celestial bodies,to plot the positions,to work out the latitude,a special cloud format

13、ion which indicates there is land close by,North Star,Sun,Clouds,Using wildlife,If seaweed was fresh and smelled strongly, the ship was close to land.,Seabirds could be used to show the way to land when it was nowhere to be seen.,Seaweed,Birds,Using the weather,fog,To help identify the position of a

14、 stream or river when ,To direct their sailing,Winds,Use the information to analyze the navigational skills and write the answers in your own words.,To find the ships position at sea a sailor used _. A sailor knew that land was nearby if he saw _ _. Sailors used _ _ to increase their speed.,the Nort

15、h Star and the sun,sea currents or tides and,winds,Using nature,clouds, fresh seaweed, nesting birds returning home in the evening or fog,What skills did sailors use to explore the seas and discover new lands?,Page 2,Using navigational instruments,1. Finding longitude,2. Finding latitude,the compass

16、,the bearing circle (方位圆),the astrolabe (星盘),the quadrant (象限仪, 四分仪),the sextant (六分仪),Read again and fill in the blanks.,There were two methods to find longitude: 1. _ 2. _ _,measuring time and speed,compass and complicated,mathematical tables,Using instruments,Write down the working principles of

17、the following instruments. Bearing circle: Astrolabe:,to compare the height of the sun now with the position of the sun at midday.,to compare the position of the ship in relation to some stars or the sun.,Quadrant:,a more precise form of the astrolabe, to measure how high stars are above the horizon

18、, and compare that measurement with previous measurements (using the ship as one of the fixed points to find its position),Sextant:,an updated version of the quadrant and so it was more accurate, to measure the angle between two fixed points outside the ship (using two mirrors to find the ships posi

19、tion).,horizon,Sun height,A Bearing Circle,Bearing the sun - height and azimuth,(The marks were used to measure the shadow of the sun and its height and position in the sky.),(方位),Read the passage and answer the following questions.,What is the use of a bearing circle, astrolabe, quadrant or sextant

20、? ( ) What is the use of a compass? ( ) A. to set the course of the ship B. to measure the position of the ship C. to measure the speed of the ship D. to tell the time,B,A,Using instruments,Skimming,Skim the text and fill in the blanks.,plot,latitude,Wildlife,way,identify,tides and currents,compass,

21、sextant,Detailed reading,1. Read the passage carefully and then answer the questions.,1) Why are speed and time important in working out the longitude of a ship? Speed and time are important in finding out the longitude of a ship because the earth moves fifteen,degrees westwards every hour. If you k

22、now your direction, speed and time, you can work out the approximate longitude or change in your position in relation to the stars.,2) Why is the position of the sun and various stars useful for working out latitude? The position of the sun and stars are useful for working out latitude because they

23、are fixed points in the sky and their movements in relation to the earth are already known. So they can be used to measure a ships position.,2. Suppose you were a sea captain aiming to sail round Africa. Discuss in groups. 1) What skills would you seek in your sailors? 2) What problems would you anticipate for this journey?,wait till the storm is over, and then find your new position and return to your original course,3. Read the chart below and fill in your plans of action to deal with them.,use knots to find your speed an