Altering the Environment — Unit test Answers

Responses may vary but should include some or all of the following information: Humans face two major environmental challenges in Dubai. The first is the lack of freshwater resources. The second is the warm and dry climate, which exacerbates pressure on scarce freshwater resources. Rapid population growth due to the discovery of petroleum in the 1960s has dramatically increased the demand for freshwater. Two technologies have helped humans survive in Dubai despite these significant environmental challenges. The invention of climate control technologies like evaporative cooling and air conditioning have allowed humans to survive in a climate with an average daily temperature of 90 degrees. The technology of desalination, which transforms saltwater into freshwater resources through the process of reverse osmosis (the heating and filtering of saltwater), has provided Dubai with 90 percent of its freshwater needs.

Responses may vary but should include some or all of the following information: Industrial, agricultural, and municipal runoffs pollute coastal areas, creating dead zones for fish.

Responses may vary but should include some or all of the following information: The construction of the Aswan Dam in Egypt has provided many benefits, but they have come with a cost. Benefits include the creation of Lake Nasser, one of the world’s largest artificial lakes; the production of hydroelectricity to supply 15 percent or more of Egyptian energy needs; and the elimination of unpredictable seasonal flooding. Costs associated with the dam include the displacement of thousands of Nile Valley residents in Egypt and Sudan; the reduction of fertile soil deposits, which has changed native plant species and required the use of more artificial fertilizers in agricultural production; and the billion-dollar price tag of the dam’s construction.