Question

    By the end of the century, if not sooner, the world’s oceans will be bluer and greener thanks to a warming climate, according to a new study.

At the heart of the phenomenon lie tiny marine microorganisms(海洋微生物) called phytoplankton. Because of the way light reflects off the organisms, these phytoplankton create colourful patterns at the ocean surface. Ocean colour varies from green to blue, depending on the type and concentration of phytoplankton. Climate change will fuel the growth of phytoplankton in some areas, while reducing it in other spots, leading to changes in the ocean’s appearance.

Phytoplankton live at the ocean surface, where they pull carbon dioxide(二氧化碳) into the ocean while giving off oxygen. When these organisms die, they bury carbon in the deep ocean, an important process that helps to regulate the global climate. But phytoplankton are vulnerable to the ocean’s warming trend. Warming changes key characteristics of the ocean and can affect phytoplankton growth, since they need not only sunlight and carbon dioxide to grow, but also nutrients.

Stephanie Dutkiewicz, a scientist in MIT’s Center for Global Change Science, built a climate model that projects changes to the oceans throughout the century. In a world that warms up by 3℃, it found that multiple changes to the colour of the oceans would occur. The model projects that currently blue areas with little phytoplankton could become even bluer. But in some waters, such as those of the Arctic, a warming will make conditions riper for phytoplankton, and these areas will turn greener. “Not only are the quantities of phytoplankton in the ocean changing. ” she said, “but the type of phytoplankton is changing.”

And why does that matter? Phytoplankton are the base of the food web. If certain kinds begin to disappear from the ocean, Dutkiewicz said, “it will change the type of fish that will be able to survive.” Those kinds of changes could affect the food chain.

Whatever colour changes the ocean experiences in the coming decades will probably be too gradual and unnoticeable, but they could mean significant changes. “It’ll be a while before we can statistically show that the changes are happening because of climate change,” Dutkiewicz said, “but the change in the colour of the ocean will be one of the early warning signals that we really have changed our planet.”

1.What are the first two paragraphs mainly about?

A.The various patterns at the ocean surface.

B.The cause of the changes in ocean colour.

C.The way light reflects off marine organisms.

D.The efforts to fuel the growth of phytoplankton.

2.What does the underlined word “vulnerable” in Paragraph 3 probably mean?

A.Sensitive. B.Beneficial. C.Significant. D.Unnoticeable.

3.What can we learn from the passage?

A.Phytoplankton play a declining role in the marine ecosystem.

B.Dutkiewicz’s model aims to project phytoplankton changes.

C.Phytoplankton have been used to control global climate.

D.Oceans with more phytoplankton may appear greener.

4.What is the main purpose of the passage?

A.To assess the consequences of ocean colour changes.

B.To analyse the composition of the ocean food chain.

C.To explain the effects of climate change on oceans.

D.To introduce a new method to study phytoplankton.

Answer

1.B

2.A

3.D

4.C

【解析】

本文为一篇说明文。一项最新研究表明，由于气候变暖，世界海洋将会变得更蓝、更绿。这一现象的原因是因为一种叫做浮游植物的微小海洋微生物，因为光线反射的作用，它们在海洋表面形成了五颜六色的图案，现在浮游植物受到海洋变暖趋势的影响，让浮游植物的生长更加旺盛，所以海洋相应会变得更蓝、更绿。

1.主旨大意题。根据第一段By the end of the century, if not sooner, the world’s oceans will be bluer and greener thanks to a warming climate, according to a new study.可知，一项新的研究表明，到本世纪末，由于气候变暖，如果不尽快的话，世界上的海洋将会变得更蓝、更绿。结合第二段At the heart of the phenomenon lie tiny marine microorganisms(海洋微生物) called phytoplankton. Because of the way light reflects off the organisms, these phytoplankton create colourful patterns at the ocean surface. Ocean colour varies from green to blue, depending on the type and concentration of phytoplankton.可知，这种现象的核心是一种叫做浮游植物的微小海洋微生物，在光线的作用下在海洋表面形成了五颜六色的图案。海洋的颜色从绿色到蓝色不等，这取决于海洋的类型和浮游植物浓度。由此可推断出这两段主要叙述了海洋生物是海洋颜色变化的原因。故选B。

2.猜测词义题。根据划线词后的Warming changes key characteristics of the ocean and can affect phytoplankton growth, since they need not only sunlight and carbon dioxide to grow, but also nutrients.可知，气候变暖会改变海洋的主要特征，并会影响浮游植物的生长。由此可判断，浮游植物很容易受到海洋变暖趋势的影响，也就是很敏感。故A项正确。

3.推理判断题。根据第四段The model projects that currently blue areas with little phytoplankton could become even bluer. But in some waters, such as those of the Arctic, a warming will make conditions riper for phytoplankton, and these areas will turn greener.可知，Dutkiewicz的模型预测，目前只有少量浮游植物的蓝色区域可能会变得更蓝。但是在一些水域，比如北极，气候变暖会使浮游植物的生长条件更加成熟，而这些水域会变得更绿了。由此可推断，浮游植物的生长条件更加成熟，浮游动植物就更多了，这些水域会变得更绿了。故D项正确。

4.主旨大意题。第一段提出文章的主旨By the end of the century, if not sooner, the world’s oceans will be bluer and greener thanks to a warming climate, according to a new study.可知，一项新的研究表明，到本世纪末，由于气候变暖，如果不尽快的话，世界上的海洋将会变得更蓝、更绿，接下来详细讲述了原因。故C项正确。