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请问斑斑今天的题是这个么？
问：什么是末次冰期(LGM)？
答：
The Last Glacial Maximum (LGM) refers to the time of maximum extent of the ice sheets during the last glacial period, approximately 20,000 years ago. This extreme persisted for several thousand years.
At this time, ice sheets covered the whole of Iceland and all but the southern extremity of the British Isles. Northern Europe was largely covered, the southern boundary passing through Germany and Poland, but not quite joined to the British ice sheet. This ice extended northward to cover Svalbard and Franz Josef Land and eastward to occupy the northern half of the West Siberian Plain, ending at the Taymyr Peninsula. In North America, the ice covered essentially all of Canada and extended roughly to the Missouri and Ohio Rivers, and eastward to New York City. A person could theoretically walk from North America to Europe across the frozen north Atlantic ice sheet.
In the Southern Hemisphere, the Patagonian Ice Sheet covered Chile and western Argentina north to about 41 degrees south. Ice sheets also covered Tibet (scientists continue to debate the extent to which the Tibetan Plateau was covered with ice), Baltistan, Ladakh, the Venezuelan Andes and the Andean altiplano. In Africa, the Middle East and Southeast Asia, many smaller mountain glaciers formed, especially in the Atlas, the Bale Mountains, and New Guinea.
The Ob and Yenisei Rivers had their flows stopped by the vast ice sheets, creating huge pluvial lakes.
Permafrost covered Europe south of the ice sheet down to present-day Szeged and Asia down to Beijing. In North America, latitudinal gradients were so sharp that permafrost did not reach far south of the ice sheets except at high elevations.
The Indonesian islands as far east as Borneo and Bali were connected to the Asian continent in a landmass called Sundaland. Palawan was also part of Sundaland, while the rest of the Philippine Islands formed one large island separated from the continent only by the Sibutu Passage and the Mindoro Strait. [1] Australia and New Guinea were connected forming Sahulland. Between Sundaland and Sahulland, Wallacea remained islands, though the number and width of water gaps between the two continents were considerably smaller.
斑斑有时候还是很好滴  谢谢哈 |
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楼主
发表于 2009-7-29 22:51
斑斑今天闹心了