视听阅读第二册 Unit 2 Polar Bears in Trouble.ppt

Watch, Listen and Read (Book 2) Polar Bears Background Info Polar Bear white Arctic regions on drifting oceanic ice floes swift, wide-range traveler, good swimmer food:seal,fish,seaweed,grass,birds,caribou,etc. (omnivorous animal 杂食) maritime bear Hudson Bay 2nd largest bounded by with Canadian bordering states connect Atlantic the Arctic a polar region located at the northernmost part of the Earth. consists of the Arctic Ocean and parts of Alaska (United States), Canada, Finland, Greenland (Denmark), Iceland, Norway, Russia, and Sweden. consists of a vast ocean with a seasonally varying ice cover, surrounded by treeless permafrost The area can be defined as north of the Arctic Circle it can be defined as the region where the average temperature for the warmest month (July) is below 10 °C (50 °F); the northernmost tree line roughly follows the isotherm等温线 at the boundary of this region. Location of the Arctic Artificially coloured topographical map of the Arctic region Map from the U.S. Geological Survey shows projected changes in polar bear habitat from 2001 to 2010 and 2041 to 2050. Red areas indicate loss of optimal polar bear habitat; blue areas indicate gain. the situation is threatening the survival of the species, and is considered a troublesome indicator of the impact of global warming on the whole Arctic region. Warm up I. 1.fur 2. carnivore 3. blubber 4. Arctic 5. marine mammal II. FBCGDAE Part 1 I.FTTTF II. Edge inhospitable thrive mammal survival frozen adjustments insulated reserves III. 1. One animal actually thrives in these freezing, lonely surroundings. 2. These marine mammals spend most of their lives on frozen seas. 3. Polar bears don’t enjoy the luxury of an uninterrupted winter. 4. Unlike the high Arctic, there’s no permanent ice pack here. 5. When the Bay melts, the bears are forced to shore. Part 2. I. When the weather starts to turn cold, large numbers of them gather around the coast. At this time, peo