2006年VOA标准英语-Satellites Show Dramatic Melting At Poles

By Paul Sisco
Washington, DC
24 May 2006
 
watch Melting Poles report

NASA scientists, working with 10 years of satellite data, find a dramatic thinning of ice around the edges of Greenland, and Antarctica too.   

satellite view of earth    
  
Using satellite technology and various measurements, NASA scientists confirm the earth is melting at both poles.  In the north, at the Arctic, the melting of Greenland's three-kilometer thick ice sheet had been expected, though not as dramatically as it is now happening.  But in the south, many believed the far more massive ice sheets covering Antarctica would increase in the 21st century. That's not so, according to the NASA observations and data.  Despite increasing snowfall, Antarctica's ice sheets are shrinking. 

Isabella Velicogna  
  
Research Scientist, Dr. Isabella Velicogna is with the University Of Colorado explains the evidence of melting. "What is unique about what we found is that for the first time, we are able to say, we are sure that the Antarctic ice sheet is losing mass, and at a significant rate."

 
Jaz Zwally
  
NASA Glaciologist, Dr. Jay Zwally. “The warmer ocean comes underneath¹ the ice shelves and melts them from the bottom, and warmer air from the top melts them from the top so they're thinning and eventually they get to a point they go poof?"

The findings come from, Grace, which stands for "Gravity Recovery and Climate Experiment ... twin satellites orbiting the earth in tandem² that are constantly measuring variations in the Earth's mass and gravitational field.  Dr. Isabella Velicogna, authored the study. "We studied the changing mass of the Antarctic ice sheet using the data from the gravity recovery and climate experiment, Grace, and we found Antarctica is losing mass and is losing a significant about of mass (at) about 152 cubic kilometer a year, which is equivalent to how much water the United Stares is using in three months.  So it's a lot of water." 

 
James Hansen
  
Combining data from the grace experiment with other research tools, scientists tracking Antarctica's melting ice sheet express concern.  NASA Earth Science Director, James Hansen. "If we pass a certain point of no return then we're going to get large sea level rise even though it would take a century or two or three to play out fully³, we will have started a process we just can't stop."

Scientists say rising sea levels are a great danger to coastal⁴ villages and cities.  While the new analysis shows fluctuations⁵ in Antarctica's ice sheet and even some thickening in parts, melting over the last five years has contributed to a sea level rise of 1.2 millimeters.  This suggests a small but significant rise in sea levels of almost half a millimeter annually⁶.

1 underneath   

adj.在...下面，在...底下；adv.在下面

参考例句：

• Working underneath the car is always a messy job.在汽车底下工作是件脏活。
• She wore a coat with a dress underneath.她穿着一件大衣，里面套着一条连衣裙。

2 tandem   

n.同时发生；配合；adv.一个跟着一个地；纵排地；adj.（两匹马）前后纵列的

参考例句：

• Malcolm's contract will run in tandem with his existing one.马尔科姆的合同将与他手头的合同同时生效。
• He is working in tandem with officials of the Serious Fraud Office.他正配合欺诈重案办公室的官员工作。

3 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

4 coastal   

adj.海岸的，沿海的，沿岸的

参考例句：

• The ocean waves are slowly eating away the coastal rocks.大海的波浪慢慢地侵蚀着岸边的岩石。
• This country will fortify the coastal areas.该国将加强沿海地区的防御。

5 fluctuations   

波动，涨落，起伏( fluctuation的名词复数 )

参考例句：

• He showed the price fluctuations in a statistical table. 他用统计表显示价格的波动。
• There were so many unpredictable fluctuations on the Stock Exchange. 股票市场瞬息万变。

6 annually   

adv.一年一次，每年

参考例句：

• Many migratory birds visit this lake annually.许多候鸟每年到这个湖上作短期逗留。
• They celebrate their wedding anniversary annually.他们每年庆祝一番结婚纪念日。