首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Spring is usually prime food time for some 1,200 polar bears along Canada’s Hudson Bay. Each year they plunder the bay’s ice flo
Spring is usually prime food time for some 1,200 polar bears along Canada’s Hudson Bay. Each year they plunder the bay’s ice flo
admin
2010-09-10
57
问题
Spring is usually prime food time for some 1,200 polar bears along Canada’s Hudson Bay. Each year they plunder the bay’s ice floes, smash open the snow caves of seals, and stuff themselves on seal pups. But in recent years the bears’ feast has turned into slimmer pickings. Why?
Temperatures at Hudson Bay have risen by one half degree Fahrenheit every decade since 1950. Winter ice on the bay melts three weeks earlier than it did just 25 years ago, which means three fewer weeks of polar bear mealtime. Result: Polar bears are 10 percent thinner and produce 10 percent fewer cubs than they did 20 years ago. And though climatologists hotly debate the causes behind Earth’s Arctic meltdown, "these changes are startling and unexpected,’ says James McCarthy, co-leader of the United Nations Intergovernmental Panel on Climate Change.
The plight of polar bears is just the tip to the iceberg when it comes to mounting evidence of global warming. "There’s definitely a stark contrast with the way things were at the start of the 20th century," says atmospheric scientist Leonard Druyan, of Columbia University. Recent data show the volume of Arctic sea ice has shrunk 20 percent since the 1950s; glaciers around the world are melting at rapidly increasing rates. Rivers and lakes in North America, Asia, and Europe now freeze about nine days later and thaw 10 days earlier than they did a century ago.
Most scientists believe the only effective strategy to halt global warming is to drastically reduce emissions of powerful air pollutants like carbon dioxide, which accounts for two-thirds of all greenhouse gases. In the last 150 years, the surging use of fossil fuels coal, oil, and natural gas -- has released 270 billion tons of carbon into the air in the form of carbon dioxide. Fortunately, oceans, plants, and soils absorb more than half of all atmospheric carbon dioxide -- without them world temperatures might have already soared at an alarming rate.
According to the article, what is one of the results of rising temperatures at Hudson Bay?
选项
A、Polar bears have become extinct.
B、Polar bears have less of an appetite.
C、A reduced amount of time for polar bears to feed.
D、The changes are startling and unexpected.
答案
C
解析
属事实细节题。第二段指出,哈得逊湾的气温不断上升,使北极熊的捕食期缩短。
转载请注明原文地址:https://kaotiyun.com/show/Bk87777K
0
大学英语四级
相关试题推荐
A、Loneliness.B、Isolation.C、Reproduction.D、Entertainment.B文章的最后一部分直接提到,为了解决熊猫的isolationproblem而建立了“BambooCorridors",因此答案是B。
TheH5N1virusdoesnotusuallyinfecthumans.In1997,however,thefirstcaseof【S1】______fromabirdtoahumanwasseendu
A、EconomicconditionsarebetterinBritainthaninotherEuropeancountries.B、Britainwon’taccepteurosuntilthereareenoug
BuyingaNewCarDecideWhatYouCanAfford,Want,andNeedAcarisoneofthemostimportantandcostlypurchasesyou
TheSacrificeatMasadaOnediscoveryalwaysleadstoanother.ArchaeologistsworkingneartheDeadSeabecamecuriousabout
A、Thepersonnelmanagershouldbefiredforinefficiency.B、Afewengineersshouldbeemployedtomodernizethefactory.C、Thee
Beforeinvestingincommonstocks,oneshouldbeawareofboththeiradvantagesanddisadvantages.Oneadvantageistheirhighp
A、BecauseitishigherthantheincomeoftheaverageAmericanfamilies.B、Becausefarmershavelittlemoneyleftafterpayinga
BasictoanyunderstandingofCanadainthe20yearsaftertheSecondWorldWaristhecountry’simpressivepopulationgrowth.F
TherearemanyreasonswhyfamilylifeinBritainhaschangedsomuchinthelastfiftyyears.The【B1】______ofwomenintheearl
随机试题
1mol葡萄糖在有氧氧化和糖酵解时生成的ATP数量之比是
有关主动脉瓣关闭不全的病理生理改变,下列哪项是错误的
COPD患者,出现下列体征应考虑慢性肺源性心脏病的诊断,除了
吸气性呼吸困难见于
关于叶状乳头叙述正确的是( )
甲企业与乙企业签订买卖合同,约定乙企业应于8月30日前交货,货到7日内甲企业付款。同年8月10日,甲企业被法院依法宣告破产。对该合同的处理,下列选项哪一个是正确的?
图示结构a杆破坏后。结构将变成哪种结构?
关于基金管理人的内部控制,以下表述错误的是()。
(2013年)企业高层管理人员在制定人力资源规划的过程中应该承担的工作有()。
新课改中教育观念的转变主要是指()①教育功能观的转变②教师观的转变③学生观的转变④教学观的转变⑤评价观的转变
最新回复
(
0
)