The Frozen Ocean: A Grade 6 Reading Comprehension Worksheet on the Arctic Ocean.

Reading Comprehension Worksheet: THE FROZEN OCEAN

#### Passage Summary
The passage provides information about the Arctic Ocean, including its size, depth, exploration challenges, surrounding landmasses, temperature, salinity, biodiversity, and the impact of climate change. Key points include:
- The Arctic Ocean is the smallest and shallowest of the world's major oceans.
- It is least explored due to ice cover throughout the year.
- Its surface temperature can drop below -2°C due to salt content.
- Phytoplankton plays a crucial role in the Arctic's biodiversity and food chain.
- Frail ice forms as temperatures drop, trapping pockets of salty water.
- Summer brings melting ice, reducing the surface cover significantly.

#### Questions and Answers

1. How much area does the Arctic Ocean cover?
- Answer: The Arctic Ocean covers an area of about 5,427,000 square miles.

2. Why is the Arctic Ocean the least explored?
- Answer: The Arctic Ocean is the least explored primarily because ice partly covers it throughout the year.

3. What is the Arctic Ocean’s surface temperature?
- Answer: The Arctic Ocean’s surface temperature varies seasonally but can drop to -2°C due to the presence of salt, which lowers the freezing point of seawater.

4. What is the most important aspect of its biodiversity?
- Answer: The most important aspect of the Arctic Ocean’s biodiversity is the presence of micro-algae called phytoplankton, which form an essential component of the food chain.

5. What is the ‘frail ice’?
- Answer: Frail ice is a salt-free solution that forms when tiny ice needles start to form, created by phytoplankton regulating the amount of ice formation. As the temperature continues to fall, this ice thickens and traps pockets of salty water in its layers.

6. What happens in summer in the Arctic Ocean?
- Answer: In summer, the ice melts, and the surface cover can be reduced to half of what it was during winter. This period is characterized by continuous daylight (sun out day and night), which allows life to thrive, but organisms struggle to survive during the dark days of winter.

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Explanation of Solutions

Each question is directly answered based on the information provided in the passage. Here’s a breakdown:

1. Area Covered: The passage explicitly states the area covered by the Arctic Ocean as "about 5,427,000 square miles."
2. Least Explored Reason: The passage mentions that the Arctic Ocean is least explored because "ice partly covers it throughout the year."
3. Surface Temperature: The passage explains that the surface temperature can drop to -2°C due to the presence of salt, which lowers the freezing point of seawater.
4. Biodiversity Aspect: Phytoplankton is highlighted as the most important aspect of biodiversity, forming a key part of the food chain.
5. Frail Ice Definition: The passage describes frail ice as a salt-free solution formed by ice needles and regulated by phytoplankton, which thickens and traps salty water.
6. Summer Changes: The passage details that in summer, the ice melts, reducing the surface cover, and there is continuous daylight, allowing life to thrive.

By carefully reading and analyzing the passage, each question can be answered accurately.

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Final Answer

\boxed{
\begin{aligned}
1. & \text{ About 5,427,000 square miles.} \\
2. & \text{ Because ice partly covers it throughout the year.} \\
3. & \text{ Can drop to -2°C.} \\
4. & \text{ Presence of phytoplankton.} \\
5. & \text{ A salt-free solution formed by ice needles, thickening and trapping salty water.} \\
6. & \text{ Ice melts, reducing the surface cover, and there is continuous daylight.}
\end{aligned}
}