Describe important characteristics of the last glacial maximum, including ice extent and thickness, crustal deformation, and changes in air temperature and sea level
What will be an ideal response?
Answer: Ice sheets advanced to within 40° of the equator, covering the ground to a depth of several kilometers. Tremendous quantities of water were transferred from ocean to land, building sheets 3,500 to 4,000 m (2.1 to 2.5 mi) thick. Given enough time, this would be enough to depress the continental crust by more than 800 m (0.5 mi). When the ice melted, the land surface gradually expanded upward toward its original level. On land, temperature changes varied greatly by proximity to the ice sheets and to the ocean. For example, in western North America, maritime air masses kept temperatures to within 4°C to 5°C (7°F to 9°F) of modern values. This contrasts sharply with the area that is now Tennessee and South Carolina, where temperatures were 15°C to 20°C (27°F to 36°F) colder than they are now. Temperature changes in the tropics were smaller, perhaps 4°C to 5°C (7°F to 9°F). Snowline was about 1,000 m (3,300 ft) lower, which translates into a temperature decrease of 5°C to 6°C (9°F to 11°F) for elevations above 2,000 m (6,600 ft).
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A thin math book and a thick science book are joined by a string on a horizontal friction-free table. One book is pushed off the edge of the table. As it falls, the other book (different mass) is dragged horizontally across the table surface. Acceleration of the books is
A. between zero and g. B. g. C. zero. D. g/2. E. greater than g.
You find some limestone rock in southern Indiana and notice that it has fossil trilobites in it. Later you find the same fossil trilobites in a limestone in Colorado. From this you determine that the two rock types were deposited during the same time period using what concept or principle?
A. principle of Unconformities B. principle of Cross-cutting Relationships C. principle of Uniformitarianism D. principle of Inclusions E. principle of Correlation using fossils
A closed system means that neither energy nor matter enter or leave the system
Indicate whether the statement is true or false
Current ethanol production in Brazil is different from ethanol production in the United States because in Brazil,
A) special enzymes that break down cellulose into sugars are used. B) ethanol is used to heat homes and generate electricity. C) sugar cane is used instead of corn. D) natural gas is used to generate ethanol.