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冀教版八年级下unit7 lesson42
New words1. million n. 百万 2. square n.平方，广场，正方形 3. Rocky Mountain 落基山脉 4. Spanish adj.西班牙（人）的n.西班牙语 5. Mexican n.墨西哥人；墨西哥语 adj.墨西哥（人）的Listen to the text.1. To the south of Canada is the United States. 倒装句：用于表示一定的句子结构或强调某一 句子成分。状语位于句首的倒装： &1 当位于句首的状语是一些表示地点的介词 短语或表示运动方向的副词（如away, back, down, in, off, out, up等）时，常常引起倒装。 Away went the runners. 赛跑手们刷地跑开了。 Down came the rain. 雨哗地落下来了。&2 介词短语作地点状语，放在句首，后面跟 的是不及物动词be, come, sit, live, stand, lie, exist等时常常引起倒装。 Next to the table is a chair. 桌旁有把椅子。 At the South Pole lies Antarctica, the coldest and most desolate region on earth. 南极洲位于南极，它是地球上最寒冷和最荒 凉的地区。? ? ? ? ?in, to, on和off在方位名词前的区别。 in表示A地在B地的范围内。 Japan is in the east of Asia. 日本在亚洲的东部。 to表示A地在B地的范围之外，且相隔有一 定距离。 ? Mexico is to the south of the United States. ? 墨西哥位于美国的南边。? ? ? ? ?on表示A地与B地接壤毗邻。 Guangdong is on the south of Hunan. 广东在湖南南边。 off表示“离...一些距离”。 New Zealand lies off the eastern coast of Australia. ? 新西兰位于澳大利亚东海岸附近。? 2. the third most common language ? 在形容词最高级前面加上序数词，即“the + 序数词+形容词最高级+名词”表示“第... 最...” ? Hainan Island is the second largest island of China. C ? 海南岛是中国第二大岛。 ? Tony is only shorter than Jim. He is _____ in his class. ? A two tallest B the two tallest? ? ? ? ? ? ?3. leave v.离开，丢下 leave +地点，表示离开某地 When did you leave Shanghai? 你什么时候离开上海的？ leave for + 地点，表示动身去某地 Next Friday, Alice is leaving for London. 下周五，爱丽丝要去伦敦了。? leave +地点+for+地点，表示离开某地去 某地。 ? Why are you leaving Shanghai for Beijing? ? 你为什么要离开上海去北京呢？ ? 在表示“把某物忘在某地”时，要用leave。 ? Li Ming left his English book in my house. ? 李明把他的英语书忘在我家了。 ? Don't worry. There is much time left. ? 不用担心，还剩下很多时间。
新冀教版八年级英语下册Unit7 Lesson 42 The New Club导学案_英语_初中教育_教育专区。Unit7 Lesson 42 The New Club 导学案 Leaning aims(学习目标) : 1....【最新】冀教版英语七年级下册Unit7 Lesson42教案_英语_初中教育_教育专区。Unit 7 Lesson 42 Know Yourself 教案 Teaching Aims: 1. Master the new words: ...冀教版英语八年级下册Unit7 Enjoy Your Hobby全单元导学案(Lesson37-Lesson42)_英语_初中教育_教育专区。八年级英语(下)Unit 7自主学习导学案 班级 姓名 时间 ...Unit 7 Know Our World(Lesson 42)学案(冀教版八年级下册)_英语_初中教育_教育专区。Unit 7 Know Our World(Lesson 42)学案(冀教版八年级下册) ...【最新】冀教版八年级英语上册Unit7《Lesson 42 The new club》教案_英语_初中教育_教育专区。Unit7《Lesson 42 The new club》教案 【认知学习目标】 : 1....冀教版八年级英语下册Le... 暂无评价 22页 2下载券 七年级英语下册 Unit 6...西塬中学导学方案科目 English Miss Luo 课题 Lesson 42 North America 时间 ...八年级英语上册 Unit 7 Lesson 42 The New Club教案 (新版)冀教版_英语_初中教育_教育专区。Unit 7 Lesson 42 The New Club Ⅰ. Target language 1. Words...冀教版初中英语八年级下册unit7教案_其它课程_小学教育_教育专区。Lesson 49: Let’s Learn Geography! Teaching Content: Mastery words and expressions: geography...八年级英语下册 Unit 7 Know Our World lesson 42 North America教案 (新版)冀教版_英语_初中教育_教育专区。八年级英语下册 Unit 7 Know Our World lesson 42...八年级英语上册 Unit 7 Lesson 42 The New Club课时作业(新版)冀教版_英语_初中教育_教育专区。Unit 7 Lesson 42 The New Club 一.短语翻译: 1.和…….一...
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The mystery and forbidding magnificence of the polar regions have fascinated scientists and explorers throughout history. The Arctic Ocean is found at the North Pole and Antarctica is found in the Southern Ocean at the South Pole. Antarctica is covered in ice and is the coldest place on earth. With unusual wildlife and unexplored territories, the polar regions are a place of great wonder and natural resources.
The Arctic
The Arctic Ocean and parts of Russia, Canada, Greenland, Lapland, Norway, Alaska, and Iceland make up the Arctic region of the North Pole. North of the Arctic Circle at 66&33&N, it is the land of the midnight sun and polar nights. There is a July isotherm at 10&C or 50&F in accordance with the treeline. The huge, ice-covered Arctic is considered an ocean with eight states even though many scientists simply consider these areas the subarctic region. Although there are no trees and the ground is frozen, the Arctic is home to fish, marine mammals, birds, land animals, and humans who have adapted to extreme conditions. Although the Arctic remains a mystery to many, its importance to the Earth's balance should not be underestimated. As a place sensitive to climatic change and simultaneously in a key position to influence the climate of the rest of the world, the conditions of the Arctic may foretell the fate of the world, which has made the Arctic region the subject of much environmental study.
The magnetic pole changes everyday, so the North Pole is never in one location in reference to the magnetic north pole. These changes are observed by scientists and affect compass readings in this region. The Arctic region is considered to be all areas north of the Arctic Circle at 66&33&N Latitude. Other landmarks are where the winter sea ice ends in the south or where the trees begin to grow on land.
The Arctic is called the land of the midnight sun because when the North Pole faces away from the sun it is night for half of the year and when it faces towards the sun it is day for the rest of the year. The Arctic Ocean is bordered by Canada, Greenland, Russia, and Alaska with the North Pole located in the middle. Due to the ice cover, it is possible to walk on 2- m ice flows that float on
m of water. Temperatures are
in the winter and
in the summer. These extreme conditions provide the perfect location for the study of
and unusual animals like the , , , and many bird species. Scientists have studied the Arctic through expeditions for centuries. More modern research utilizes cruise ships, scientific vessels, ice camps and research facilities rooted permanently in the region. Some scientists are using satellites and long-term unmanned instruments placed in the icy ocean to collect data. Computer models are also used to see what the effects would be if the environment changed.
Nature and Natural Resources
A land with vast natural resources including tourism, oil, gold, metals, and diamonds&the Arctic is valuable in a number of ways. Unfortunately, because everything living is connected, pollutants and toxic metals from industrial countries are transported to the Arctic through various ecological cycles. Many of the natural resources that the animals and people of the Arctic rely on have become contaminated by waste from other places. The greenhouse effect is also changing the Arctic by decreasing permafrost and sea ice, changing precipitation, warming the air, and allowing hazardous UVB radiation to penetrate the ozone. If the Arctic sea melts, it is possible that the sea level will rise and unwanted and severe consequences will occur in coastal countries worldwide. It is unclear whether tourism will benefit the Arctic region or whether it will create additional environmental problems. The Arctic is one of the last wild places on the globe with exotic species, significant , and important habitats. It is also one of the most fragile and easily disturbed areas.
Arctic Cultures
Another animal living in the Arctic successfully is the human, with many Native societies and an impressive history. Now populated by people of European descent, the culture of the indigenous people must be preserved to ensure that their carefully developed survival skills will be passed on to future generations. Indigenous people make up about 70% of the population in the mainland areas of the Bering, Beaufort, and Chukchi Seas. In Alaska, there are only three main groups of natives: , , and . About 50,000-70,000 native people inhabit both Russia and Alaska combined. The Canadian Arctic has 50,000 native people making up over half of the population. The main minority categories here are Indian, Inuit and . The protection of the native people is not only important for the preservation of survival skills but also because they are role models for sustainable living.
The Changing Arctic
In the last 30 years or so, the Arctic has experienced warmer spring temperatures in Alaskan regions, warmer winters in Northern European regions, melting sea ice in the center of the Arctic, and the invasion of tundra by wet and shrub lands in Alaska, Canada, and Siberia. When the resources available in the Arctic are in full use, ecosystems and local cultures could soon experience dramatic change with repercussions felt all over the world. A climate impact assessment was released in 2004 modeling some of the changes that may occur in the Arctic if it continues to be affected by waste from other areas and unsustainable development.
Data from 50 yea therefore, it is difficult to assess how significant recent changes in the Arctic are. Changes also vary among regions as can be observed with Alaska, which is warming, and Canada, which is cooling. Some change however, there is significant evidence that the greenhouse effect is responsible for much of the climatic variation. Most changes over small periods of time are likely to be natural, while those over long periods of time may be related to human activity. Although there have been reports of large areas of open water in the North Pole, it is more important to focus on the gradual thinning of ice in large areas over a long period of time. The thinning of ice will disrupt the heat balance in the northern hemisphere and could also affect the circulation of ocean waters.
Environmental impact assessment
Due to the relative lack of scientific data, it will be necessary for local people, businesses, politicians, and scientists to work together to provide information about the Arctic to develop an environmental impact assessment. After data is collected, it must be accessible to locals and used effectively to plan the next stages of resource management.
Understanding the influence of the Arctic on the earth's climate and its natural environment is essential to understanding the future of the global climate and environment and to the future of the Arctic region's natural resources. Partnerships such as the
comprised of scientists, the , the , and regional efforts.
The Antarctic
The Southern Ocean
The recently designated Southern Ocean envelops the continent of Antarctica and is the fourth largest ocean in the world. Formerly the Southern Ocean was a traditional mariner's term, but the name was made official by the
in 2000. The Southern Ocean was previously considered by non-mariners to be the location where the Atlantic, Pacific, and Indian Oceans stretched to Antarctica.
The ring of water enveloping the continent of Antarctica is located between 60& S latitude and 360& S longitude. Connected with the
the Southern Ocean includes the , , , , , and part of the . The coastline length is
km and the area is
km². The Antarctic Circumpolar Current, the world's largest ocean current, moves eastward and divides the Southern Ocean from the other oceans. The Southern Ocean is 30 million years old and was formed when the Drake Passage opened between Antarctica and South America. At the northern point of the Southern Ocean is the
separating colder surface waters from warmer surface waters. The Polar Front and the Antarctic Circumpolar Current encircle the continent of Antarctica and travel down to New Zealand, and to the far South Atlantic where they meet up with the .
The temperature in the Southern Ocean is anywhere from -2 to 10&C or 28 to 50&F. The difference in temperature between the ice and the ocean often results in intense storms that make their way eastward around Antarctica. The strongest winds on Earth are found from the latitude of 40& S to the . The Southern Ocean freezes in the winter all the way to 65& S latitude in the Pacific and 55& S latitude in the Atlantic resulting in subzero ocean surface temperatures. However, in some areas the coastline remains in liquid state due to warmer terrestrial winds. The ocean surrounding Antarctica reaches down 4,000- m in most areas with a very deep and narrow . The lowest point of the Southern Ocean is
m deep in the .
The Antarctic Divergence is where the east to west drift moves waters closest to the continent in a westerly direction. Westerly winds that work most of the year
also move water that is further away from the continent in what is called the West-Wind Drift. The Coriolis Effect sends waters off to the left in the Southern Hemisphere. The Antarctic Divergence is created when the East-Wind Drift moves masses towards Antarctica while the West-Wind Drift moves them away.
The Antarctic Convergence is the odd ocean zone encircling the continent where the warmer water from the northern oceans run into the colder water from the Southern Ocean. The cold water flows under the warmer water bringing up nutrients into the Southern Ocean. Animals like
using photosynthesis can thrive here and are eaten by
to form the base layer of the food web.
Environmental issues in the Southern Ocean include concern that the increase of
through an
directly above has reduced the number of phytoplankton, the primary producers in the ocean by 15% and is mutating the DNA of fish. Fishing is extensive and several species are severely exploited such as the .
in the region causes birds to become tangled and drowned. However, seals are regaining numbers after being protected from hunting for the fur trade.
There are several international agreements specifically drawn up for this area and these include the , the , and the . Additionally, the exploitation and search for minerals is against the law in many nations south of the Polar Front. International agreements have also been made to reduce
of these oceans.
The Ice of Antarctica
The ice sheet covering about 98% of Antarctica formed 25 million years ago and holds about 75% of the Earth's water, an amount that could raise the sea level by approximately
m if melted. During the summer the ice shrinks and Antarctica actually gets smaller. The Transantarctic Mountains separate the continent into West and East Antarctica. The only continent virtually uninhabited by humans, Antarctica is the coldest, windiest, and driest place in
the world. In winter, the temperatures range anywhere from
on the coast to
further inland. Summer temperatures are still at the freezing point and will sometimes make it up to , a little warmer inland. With temperatures sometimes lower than Mars, the snow in this region never melts. Glaciers and ice sheets cover landscapes, valleys, and mountains and flow towards the slightly warmer sea. Once they arrive at the sea and begin to float freely (in a &birthing process& referred to as calving), they are called . The largest recorded iceberg was named
with an area over
km², larger than the island of .
Research in Antarctica
Due to the lack of human influence, Antarctica is a valuable region for research. Between 1956 and 1957, 12 countries collaborated in the International Geophysical Year to establish research stations, communication, rescue efforts, and weather reporting. In 1959, the Antarctic Treaty was signed with the goal of setting the region aside as a pristine and peaceful area to be freely studied by scientists with the hopes of benefiting all of mankind. This treaty also bans nuclear testing and other military weapons and no country is allowed to claim it for their own. After 30 years, the treaty was re-evaluated and found to still be a good idea. Research stations like the McMurdo Station built on volcanic rock resemble small cities. With 50,000 people from more than 25 countries working on the bases, a clean-up effort had to be initiated to take care of the trash accumulation. Now, any country working in Antarctica is responsible for packing their trash out to where it came from.
The Ecology of Antarctica
There are about 85 different types of
looking like small shrimp or lobsters located in the ocean under the name &&. Ranging in size from a centimeter in length to
cm, krill feed on
at the surface at night. For such a small creature, krill bear the huge responsibility of making up the bottom level of the food chain for almost all of the animals of the Antarctic. Nutrient containing detritus, also known as marine snow, falls through the ocean water and is a major source of food for animals in the ocean below. The detritus is made up out of parts of dead plants and animals as well as waste and crustacean shells, bound together with mucus produced by many animals in the ocean. Most detritus particles are between 1-2 mm in size, although some can be several meters large. The climate of the planet can be influenced by this carbon sink provided by detritus falling to the sea floor.
In the Antarctic, most detritus consists of algae products and is produced between November and February due to the sunlight availability and nutrients provided by . During the , the amount of detritus produced is at a peak and krill feeding on the algae produce waste that will be eaten by animals below. Over millions of years, this process has resulted in the transport of vast quantities of algal materials to the sediment layer in Antarctica. Sediments deposited over millions of years can be studied by geological oceanographers using sediment cores to understand how populations of organisms change over time. When the change is caused factors like temperature, circulation patterns, or nutrient levels in the ocean environment, it is possible to collect clues from sediment cores. In addition to the study of Earth's history, scientists are also studying the greenhouse effect, which may melt polar ice. Polar ice melt will cause major climatic changes and can cause problems in the polar ecosystem. Parts of the Western Antarctic ice sheets are being studied carefully as an indicator for global warming effects. If one of these melts, there would be a dramatic increase in the sea level all over the world.
Other animals living in Antarctica include , , and . Penguins are found wild only in the Southern Hemisphere and there are many species living in Antarctica. The most common seals found in this region are the
(named after the explorer, ), the Ross seal (named after the explorer, ), , , , and the . Southern baleen and toothed whales are also found here.
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