首页
登录
职称英语
Alaska is disappearing slowly but surely. Since the 1950s, it is estimated t
Alaska is disappearing slowly but surely. Since the 1950s, it is estimated t
游客
2024-08-14
37
管理
问题
Alaska is disappearing slowly but surely. Since the 1950s, it is estimated that as much as 15 percent of Alaska’s area has disappeared. But how can a whole state be disappearing?
One reason for Alaska’s gradual disappearance is the melting of its glaciers. According to one geologist at the US Geological Survey, about 98 percent of Alaska’s glaciers are either unmoving or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 1960s, the average year-round temperature has increased by 5℉. Furthermore, the average winter temperature has increased by 8℉. Presently, an estimated 24 cubic miles of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 2. 5 to 10°F by the year 2100.
Another problem contributing to Alaska’s gradual disappearance is its thawing permafrost.(74)
Much of the land in Alaska was permanently, frozen for most of the year, thus maintaining its integrity
. Now, the thawing permafrost is causing a number of problems on land. Roads and utility poles are collapsing. Also, the hard permafrost which originally prevented beaches from eroding during violent storms is now melting. Affected villages are forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community.
The melting permafrost and increasing temperature are also having a negative impact on the forests of Alaska. As the permafrost under the forests melts, insects that normally don’t turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of global warming. It usually takes about two years for these beetles to grow and reproduce in very cold weather. However, due to the increase in temperatures, spruce-bark beetles are damaging as many trees in one year as they previously damaged in two. At this rate, Alaska’s forest won’t survive the turn of the century.
Some scientists believe that human activity is linked to a global increase in weather temperature. Whether the rising temperatures are caused by human activity or natural changes, the fact remains that Alaska is warming. Some others argue that global warming may be a normal trend on the Earth’s temperature chart.(75)
One theory argues that we are near the end of a so-called " Little Ice Age" , and the retreat of the glaciers is a natural result of this cycle. Whether natural or produced by humans, there is little hope for the immediate future of glaciers as we know them.
Horribly, this could be a preview of what will happen to the rest of the world in the next century. [br] Much of the land in Alaska was permanently frozen, or frozen for most of the year, thus maintaining its integrity.
选项
答案
阿拉斯加的大部分土地曾经是常年冰冻,或是一年中多数时间都保持冰冻状态,以此保持它的完整。
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3719983.html
相关试题推荐
Alaskaisdisappearingslowlybutsurely.Sincethe1950s,itisestimatedt
Alaskaisdisappearingslowlybutsurely.Sincethe1950s,itisestimatedt
Alaskaisdisappearingslowlybutsurely.Sincethe1950s,itisestimatedt
WhichAmericanstateisagroupofislandsinthePacificOcean?A、Alaska.B、Hawa
Thecostofstagingtheyear2000OlympicsinSydneyisestimatedtobeast
Thecostofstagingtheyear2000OlympicsinSydneyisestimatedtobeast
Thecostofstagingtheyear2000OlympicsinSydneyisestimatedtobeast
Thecostofstagingtheyear2000OlympicsinSydneyisestimatedtobeast
Thecostofstagingtheyear2000OlympicsinSydneyisestimatedtobeast
Thecostofstagingtheyear2000OlympicsinSydneyisestimatedtobeast
随机试题
[img]2017m4s/ct_etoeiclm_etoeiclzp_0501_20170401[/img][br][originaltext](A)Th
[img]2012q1/ct_etoefm_etoeflistz_0822_20121[/img][br]Whatcanbeinferredabou
Oneyearagotoday,youngJim’sparentshadaveryserioustalkwithhim.Th
[originaltext]M:Shanika,thanksforjoiningustoday!W:Mypleasure.M:First
SavingfortheFuture.Purposeofsaving1.Womens
领导者放手不管,下属愿意怎样做就怎样做,完全自由。上述这种领导方式属于()领导
下列哪项不属于热疗的目的A.解除疼痛 B.保暖 C.减轻出血 D.促进炎症
患者产后血性恶露13天不尽,量多、色淡、质稀、无气味,神疲懒言,小腹空坠,食少便
国家药品不良反应监测中心报告,某省药品生产企业生产的某药品疗效不确,不良反应大,
下列关于税率的说法中,正确的有()。A.比例税率分为产品比例税率、行业比例税率
最新回复
(
0
)