The Tip of the Iceberg|生机蓬勃的冰山一角

by Nadia Chung

Scientists are learning new things about icebergs all the time.

科学家不断在学习有关冰山的新知。

For many scientists, the study of icebergs is relatively new and fairly dangerous because large pieces of ice can break off and damage a boat or the iceberg can flip over without a moment's notice. Icebergs are worthy subjects to study not only because of how they were depicted in the romantic movie Titanic or the destruction they inflicted on the real Titanic. Intrigued by the ocean and prompted by the scarcity of information about what kind of impact free-drifting icebergs have on ecosystems, marine scientists have started to study how icebergs affect the physics and chemistry of the surrounding ocean water, the animals, and the congregations of phytoplankton (浮游植物)—organisms that synthesize their own food by using sunlight.

Since 2005, teams of scientists have conducted research in the Weddell Sea, an area of high iceberg concentration located on the southeastern side of the Antarctic peninsula. With the direct influence of the Antarctic climate, one might have thought the southern part of the ocean was a lifeless place. On the contrary, scientists have found that the open waters around Antarctica are rich in nutrients, such as iron and nitrate, all of which are necessary for phytoplankton to grow in seawater. The reason for this is because in these waters, there are free-drifting icebergs of up to 12 miles long that have broken off from the Antarctic ice shelves. When icebergs melt, they deliver nutrients to the surrounding water, which in turn helps them become flourishing ecosystems for phytoplankton, krill, fish, and seabirds. Researchers are calling this the halo effect because for two miles in every direction, the iceberg becomes a thriving community.

1.  Which of the following is a reason why studying icebergs is dangerous?

(A) The movie Titanic popularized icebergs.

(B) The sunken Titanic might cause damage to boats sailing above.

(C) Most pieces of icebergs are larger than the boats scientists use.

(D) They can quickly turn over without any warning.

2.  A word to replace on the contrary would be _____.

(A) conversely  (B) likewise

(C) considerably    (D) otherwise

3.  What do the final two sentences of the article imply?

(A) Only icebergs that are longer than two miles have the chance to develop a thriving community.

(B) When icebergs melt, living organisms are attracted to them.

(C) Fish that swim near icebergs have gold rings around their heads.

(D) Boats must stay two miles away from every iceberg.

标准答案: 1. (D)2. (A)3. (B)

For Your Information

威德尔海是南极洲的陆缘海之一，位于大西洋的极南部，是南冰洋的一部分，位于科茨地与南极半岛之间，为一北宽南窄的三角形海湾，总面积约 280 万平方公里。威德尔海自象岛以南的南半部全年冰封。该海以英国航海家詹姆斯‧威德尔（James Weddell）命名，他曾经在 1823 年在威德尔海探险，并到达了南纬 74 度。（数据源：维基百科）