新东方英语背诵美文50篇 第三十八篇 The Salinity of Ocean Waters
The Salinity of Ocean Waters
If the salinity 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 carried to the extreme, of course, white crystals of salt would be left behind.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted 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.
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.
新东方英语背诵美文50篇 | |
- 新东方英语背诵美文30篇 第一篇 Youth 青春
- 新东方英语背诵美文30篇 第二篇 Three Days to See(Excerpts) 假如给我三天光明
- 新东方英语背诵美文30篇 第三篇 Companionship of Books 以书为伴
- 新东方英语背诵美文30篇 第五篇 Ambition 抱负
- 新东方英语背诵美文30篇 第四篇 If I Rest, I Rust 如果我休息,我就会生锈
- 新东方英语背诵美文30篇 第六篇 What I have Lived for 我为何而生
- 新东方英语背诵美文30篇 第七篇 When Love Beckons You 爱的召唤
- 新东方英语背诵美文30篇 第八篇 The Road to Success 成功之道
- 新东方英语背诵美文30篇 第九篇 On Meeting the Celebrated 论见名人
- 新东方英语背诵美文30篇 第十篇 The 50-Percent Theory of Life 生活理论半对半