Fjord Estuary Example — Reading Comprehension

A fjord estuary is a type of estuary formed when glaciers carve deep valleys into the land during the Ice Ages. When the glaciers melt, seawater floods into these valleys, and rivers bring freshwater, creating a long, narrow estuary with steep sides. These estuaries are some of the deepest in the world.

One well-known example is the Sognefjord in Norway. This fjord estuary stretches more than 100 miles inland and reaches depths of over 4,000 feet in places. It is one of the largest and deepest fjord estuaries on Earth. In the United States, fjord estuaries can be found in Alaska, such as Kenai Fjords.

Fjord estuaries have unique characteristics:

• They are very deep and narrow, with steep cliffs.
• Their bottoms often have a “sill,” or shallow barrier, made of glacial debris, which affects water circulation.
• The deep waters below the sill often have little oxygen and little sunlight, making them home to fewer organisms.
• The upper waters, however, are rich in life and support fish, seals, seabirds, and whales.

These estuaries are important for both ecosystems and people. They provide safe harbors, fishing grounds, and stunning scenery that attracts tourists from around the world. However, fjord estuaries can be sensitive to pollution, climate change, and rising ocean temperatures.

Fun Fact: Some fjords are so deep that if you placed the Empire State Building inside, it would be completely covered by water!

How are fjord estuaries formed?

Where is Sognefjord located?

How deep is Sognefjord?

What is a “sill”?

Why is oxygen low in deep fjords?

Which animals live in upper waters?

What human use is mentioned?

Where are fjord estuaries in the U.S.?