Questions for ‘The big melt: Earth’s ice sheets are under attack’


Crane Glacier lost the protective floating ice shelf at its lower edge in 2002. Since then, the glacier has more than tripled its original speed. As the glacier sped up, it also splayed out. This caused its ice to thin in some places by 100 meters (325 feet).

Erin Pettit/Oregon State University

To accompany feature “The big melt: Earth’s ice sheets are under attack”


Before Reading

1.  Much of Earth’s surface (and some of its water) is covered by snow and ice. Why are people concerned about the melting of all of this frozen water?

2.  Name three concerns you’ve heard or suspect could occur if much of this ice and snow disappear.

During Reading:

1.  Dale Pomraning notes that much of the ice on Pine Island Glacier is melting — but in a hidden place. What is that hidden place?

2.  How much ice (in tons) has Antarctica lost since 1992, according to the story?

3.  The story says scientists fear that by 2100 ice loss could be far more dramatic than today, and be responsible for raising sea levels by how much?

4.  Where are Earth’s three major ice sheets? And what are ice sheets?

5.  Deep and very thick ice in Antarctica has been likened to “silly putty.” Why? And what’s responsible for making it that way?

6.  According to the story, what is the important job performed by floating ice shelves in Antarctica?

7.  Pomraning’s team used a hot water drill. Why did they use it? How does it work? And what did the researchers learn from their drilling?

8.  Pine Island Glacier’s ice shelf has been bending, buckling and breaking. What does the article say is the cause of this?

9.  Computer projections by Robert DeConto’s team says that if the world’s average warming reaches 3 degrees, what will happen to West Antarctica’s ice shelves?

10.  Ted Scambos is particularly concerned about West Antarctica losing its entire ice shelf. Why? What does he think can happen, and how seriouis might that be?

11.  According to the story, which glacier is losing ice off of its face faster than any other?

12.  Where is the Thwaites Glacier and what are three concerns mentioned in the story that could result if it collapses?

13.  Why does the article refer to Antarctica as a “sleeping giant?” Hint: How much of the world’s ice does it contain?

14.  Why does data on the instability of Totten and Denman glaciers in East Antarctica keep glaciologist Helen Fricker “up at night”?

15.  Why are meltwater ponds at the Thwaites glacier a concern? And what are two ways they might trigger a catastrophe?

After Reading:

1.  Some people still think that especially cold winter weather in the United States or Europe show that global warming poses little threat to a catastrophic melting of the planet’s cryosphere. Use information from the story to describe at least four sources of data that challenge that claim. 

2.  Review the threats that Earth’s melting cryosphere pose to people and ecosystems around the globe. Choose one and explain how it is imperiled. Now brainstorm with a partner about how you might effectively convey this information to your classmates, family and/or local community. Create a poster to describe those concerns and what people might do to slow the threats — or accommodate the changes they might cause. Explain the likely time frame you think that people will have in which to act.