研究人员发现地球公转轨道与气候的联系-凯发k8官网

研究人员发现地球公转轨道与气候的联系

文章来源：未知文章作者：meng 发布时间：2010-04-07 00:34 字体： [ ]　

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in an analysis of the past 1.2 million years, uc santa barbara ¹ lorraine lisiecki discovered a pattern that connects the regular changes of the earth's orbital（轨道的，眼窝的） cycle to changes in the earth's climate. the finding is reported in this week's issue of the scientific journal nature geoscience. lisiecki performed her analysis of climate by examining ocean ²（沉淀物，沉积） cores. these cores come from 57 locations around the world. by ³ ⁴, scientists are able to chart the earth's climate for millions of years in the past. lisiecki's contribution is the linking of the climate record to the history of the earth's orbit.

it is known that the earth's orbit around the sun changes shape every 100,000 years. the orbit becomes either more round or more elliptical（椭圆的，省略的） at these ⁵（间隔） . the shape of the orbit is known as its "⁶（离心率，古怪） ." a related aspect is the 41,000-year cycle in the ⁷（倾斜） of the earth's ⁸（轴，轴线） .

glaciation（冰川作用） of the earth also occurs every 100,000 years. lisiecki found that the ⁹ of changes in climate and eccentricity coincided. "the clear ¹⁰（相关，关联） between the timing of the change in orbit and the change in the earth's climate is strong evidence of a link between the two," said lisiecki. "it is unlikely that these events would not be related to one another."

besides finding a link between change in the shape of the orbit and the ¹¹ of glaciation, lisiecki found a surprising correlation. she discovered that the largest glacial cycles occurred during the weakest changes in the eccentricity of earth's orbit –– and ¹² versa（反之亦然） . she found that the stronger changes in the earth's orbit correlated to weaker changes in climate. "this may mean that the earth's climate has internal instability in addition to sensitivity to changes in the orbit," said lisiecki.

she concludes that the pattern of climate change over the past million years likely involves complicated interactions（相互作用） between different parts of the climate system, as well as three different orbital systems. the first two orbital systems are the orbit's eccentricity, and tilt. the third is "precession," or a change in the ¹³（方向，定向） of the ¹⁴ axis.

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1
n.地质学家
参考例句：
the geologist found many uncovered fossils in the valley.在那山谷里，地质学家发现了许多裸露的化石。 he was a geologist,rated by his cronies as the best in the business.他是一位地质学家，被他的老朋友们看做是这门行当中最好的一位。

2
n.沉淀，沉渣，沉积(物)
参考例句：
the sediment settled and the water was clear.杂质沉淀后，水变清了。 sediment begins to choke the channel's opening.沉积物开始淤塞河道口。

3
v.分析；分析( analyze的现在分词 )；分解；解释；对…进行心理分析n.分析
参考例句：
analyzing the date of some socialist countries presents even greater problem s. 分析某些社会主义国家的统计数据，暴露出的问题甚至更大。来自辞典例句 he undoubtedly was not far off the mark in analyzing its predictions. 当然，他对其预测所作的分析倒也八九不离十。来自辞典例句

4
沉淀物( sediment的名词复数 )；沉积物
参考例句：
when deposited, 70-80% of the volume of muddy sediments may be water. 泥质沉积物沉积后，体积的70-80％是水。 oligocene erosion had truncated the sediments draped over the dome. 覆盖于穹丘上的沉积岩为渐新世侵蚀所截削。

5
n.[军事]间隔( interval的名词复数 )；间隔时间；[数学]区间；（戏剧、电影或音乐会的）幕间休息
参考例句：
the forecast said there would be sunny intervals and showers. 预报间晴，有阵雨。 meetings take place at fortnightly intervals. 每两周开一次会。

6
n.古怪，反常，怪癖
参考例句：
i can't understand the eccentricity of henry's behavior.我不理解亨利的古怪举止。 his eccentricity had become legendary long before he died.在他去世之前他的古怪脾气就早已闻名遐尔了。

7
v.(使)倾侧；(使)倾斜；n.倾侧；倾斜
参考例句：
she wore her hat at a tilt over her left eye.她歪戴着帽子遮住左眼。 the table is at a slight tilt.这张桌子没放平，有点儿歪.

8
n.轴，轴线，中心线；坐标轴，基准线
参考例句：
the earth's axis is the line between the north and south poles.地轴是南北极之间的线。 the axis of a circle is its diameter.圆的轴线是其直径。

9
n.时间安排，时间选择
参考例句：
the timing of the meeting is not convenient.会议的时间安排不合适。 the timing of our statement is very opportune.我们发表声明选择的时机很恰当。

10
n.相互关系，相关，关连
参考例句：
the second group of measurements had a high correlation with the first.第二组测量数据与第一组高度相关。 a high correlation exists in america between education and economic position.教育和经济地位在美国有极密切的关系。

11
n.进攻，袭击，开始，突然开始
参考例句：
the drug must be taken from the onset of the infection.这种药必须在感染的最初期就开始服用。 our troops withstood the onset of the enemy.我们的部队抵挡住了敌人的进攻。

12
n.坏事；恶习；[pl.]台钳，老虎钳；adj.副的
参考例句：
he guarded himself against vice.他避免染上坏习惯。 they are sunk in the depth of vice.他们堕入了罪恶的深渊。

13
n.方向，目标；熟悉，适应，情况介绍
参考例句：
children need some orientation when they go to school.小孩子上学时需要适应。 the traveller found his orientation with the aid of a good map.旅行者借助一幅好地图得知自己的方向。

14
n.旋转；循环，轮流
参考例句：
crop rotation helps prevent soil erosion.农作物轮作有助于防止水土流失。 the workers in this workshop do day and night shifts in weekly rotation.这个车间的工人上白班和上夜班每周轮换一次。