四、 請閱讀本題所附 NASA Earth Observatory 短文，進行文章解析與評論。並請就文中內容，討論臺灣所面臨的挑戰與因應之策。(25 分)
The Impact of Climate Change on Natural Disasters
Climate change may not be responsible for the recent skyrocketing cost of natural disasters, but it is very likely that it will impact future catastrophes. Climate models provide a glimpse of the future, and while they do not agree on all of the details, most models predict a few general trends. First, according to the Intergovernmental Panel on Climate Change, an increase of greenhouse gases in the atmosphere will probably boost temperatures over most land surfaces, though the exact change will vary regionally. More uncertain—but possible—outcomes of an increase in global temperatures include increased risk of drought and increased intensity of storms, including tropical cyclones with higher wind speeds, a wetter Asian monsoon, and, possibly, more intense mid-latitude storms.
Global warming could affect storm formation by decreasing the temperature difference between the poles and the equator. That temperature difference fuels the mid-latitude storms affect the Earth's most populated regions. Warmer temperatures could increase the amount of water vapor that enters the atmosphere. The result is a hotter, more humid environment. At the equator, where conditions are already hot and humid, the change isn't expected to be large. At the poles, however, the air is cold and dry; a little extra heat and water vapor could raise temperatures greatly. As a result, global warming may cause the temperature difference between the poles and the equator to decrease. And as the difference decreases, so should the number of storms, says George Tselioudis, a research scientist at NASA Goddard Institute for Space Studies (GISS) and Columbia University. But even as a warming climate might decrease the overall number of storms that form, it could increase the number of intense storms. As temperatures continue to rise, more and more water vapor could evaporate into the atmosphere, and water vapor is the fuel for storms.
The combined result of increased temperatures over land, decreased equator-versus-pole temperature differences, and increased humidity could be increasingly intense cycles of droughts and floods as more of a region's precipitation falls in a single large storm rather than a series of small ones. A warmer, wetter atmosphere could also affect tropical storms (hurricanes), but changes to tropical storms are harder to predict and track. Some scientists have speculated that a warmer climate that allows more intense storms to develop would also spawn more hurricanes. Warmer temperatures may also heat ocean waters farther from the Equator, expanding the reach of large tropical storms. But there is little evidence to support the either of these theories, says Kerry Emanuel, a professor of tropical meteorology and climate in the Massachusetts Institute of Technology's Program in Atmospheres, Oceans, and Climate.
The one way in which global warming could impact hurricanes is by making them more intense. More heat and water in the atmosphere and warmer sea surface temperatures could provide more fuel to increase the wind speeds of tropical storms. Warming that has already occurred since 1980 has increased sea surface temperatures 0.3 degrees Celsius, which should increase the maximum potential wind speed of hurricanes by 1 knot, according to hurricane intensity models. But increases that small could not have been observed yet. Even if tropical storms don't change significantly, other environmental changes brought on by global warming could make the storms more deadly. Melting glaciers and ice caps will likely cause sea levels to rise, which would make coastal flooding more severe when a storm comes ashore.
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