首页
登录
职称英语
If the salinity(含盐量)of ocean waters is analyzed, it is found to vary only sl
If the salinity(含盐量)of ocean waters is analyzed, it is found to vary only sl
游客
2023-07-22
64
管理
问题
If the salinity(含盐量)of ocean waters is analyzed, it is found to vary only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation—conversion of liquid water to water vapor. In this manner, the salinity is increased, since the salts stay behind. If this is carded to the extreme, of course, white crystals of salt would be left behind.
The opposite of evaporation is precipitation(降水), such as rain, by which water is added to the ocean. Here the ocean is being diluted(稀释)so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by evaporation, or decreased by the addition of fresh water by precipitation or runoff(形成地表水部分的降雨).
Normally, in tropical regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly-formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, off Antarctica, the densest water in the oceans is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portions of the-oceans of the world. [br] The best title of the passage can be"______"
选项
A、Typical Oceans and Their Respective Features
B、The Causes of the Changes in Salinity of Ocean Water
C、Different Oceans Have Different Salinity
D、The Precipitation and Evaporation of Oceans
答案
B
解析
本文第3句是全文的主题句,告诉读者三种致使海洋盐分变化的原因,并逐一介绍这三种原因,选项 B比较全面地归纳了本文的主题。
转载请注明原文地址:https://tihaiku.com/zcyy/2858881.html
相关试题推荐
Ifthesalinity(含盐量)oceanwatersisanalyzed,itisfoundtovaryonlysli
Ifthesalinity(含盐量)oceanwatersisanalyzed,itisfoundtovaryonlysli
Ifthesalinity(含盐量)oceanwatersisanalyzed,itisfoundtovaryonlysli
Ifthesalinity(含盐量)oceanwatersisanalyzed,itisfoundtovaryonlysli
Ifthesalinity(含盐量)oceanwatersisanalyzed,itisfoundtovaryonlysli
Ifthesalinity(含盐量)ofoceanwatersisanalyzed,itisfoundtovaryonlysl
Ifthesalinity(含盐量)ofoceanwatersisanalyzed,itisfoundtovaryonlysl
Ifthesalinity(含盐量)ofoceanwatersisanalyzed,itisfoundtovaryonlysl
Ifthesalinity(含盐量)ofoceanwatersisanalyzed,itisfoundtovaryonlysl
Ifthesalinity(含盐量)ofoceanwatersisanalyzed,itisfoundtovaryonlysl
随机试题
Sleepisveryancient.Intheelectroencephalographic(脑电图仪的)senseweshare
()根据主电路中各电动机和执行元件的控制要求,找出控制电路中的每一个控制环节,
患者,男性,50岁。住感染病区,使用避污纸的正确方法是A.掀页撕取 B.戴手套
内部审计的目标就是审查评价。
治疗脾肾阳虚,五更泄泻常用中药是A.干姜B.附子C.肉桂D.山茱萸E.吴茱萸
关于卵磷脂小体的特点,错误的是( )。A.圆形 B.卵圆形 C.大小不均
防小动物设施应满足()。防小动物挡板应编号,标志清楚,外观完好、无破损,防鼠
如图所示,工厂生产的模具是一个将底面半径为6厘米、高为10厘米的圆柱体切去一部分
A
Ⅱ级无损检测人员不可进行的工作是( )。A.编制一般的无损检测程序 B.独立
最新回复
(
0
)