With the development of science,scientists have discovered more about the world.(1)____________________________.No matter what action is taken, scientists say there are already enough greenhouse gases in the atmosphere to cause a major warming.As a result,scientists and government officials are focusing on how society might adapt to rising sea levels,changing agricultural zones, changing climates and other problems.(2)___________________________________________________.Agricultural researchers are developing heat-resistant and draught-resistant crops that might replace traditional crops if the climate changes.How long it will take for maximum warming to be reached is uncertain because the oceans slow such warming.Most scientists expect the maximum warming to take place by the second half of this century.(3)____________________________________________.Some leading experts regard a rise of 1 meter,a little more than three feet.
scientists say world costal areas much prepare now for rise in sea level.
already state the local government along the coast of United States are studying to plan for possible long-term rise in the sea level and few have taken action to cope with it.
if levels of greenhouse gases in the atmosphere double, sea level will rise , estimated the average rise are from 1.5feet to 6.5feet.
发表于 2013-5-16 10:47
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发表于 2013-5-20 13:16
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