002 - The Glacial System
How is a glacier a system?
There are lots of subject specific words for this lesson but don't panic as there will be time to find their definitions for one of the activities. The key groups of words are below:
Define the words above by using the 'Useful Links' below:
Activity One - Open or Closed?
Throughout Geography you will come across a number of different systems to help explain how change occurs. Most of these systems are open as they have clear inputs and outputs. But what really are open and closed systems and how would you categorise a glacier system? Answer the following questions in full sentences.
What is a system?
What is a closed system?
What is an open system?
How would you categorise a glacier system? Explain your answer.
Activity Two - It is all about balance...
From the previous activity you have seen that a glacier has clear inputs and outputs. For a glacier to maintain its mass there needs to be a balance between the two throughout the year. For example, the glacier may gain mass during the colder months and lose mass during the warmer months of the year. It is never quite that simple, and at the moment the impact of global warming is having a detrimental effect on glacial ice mass. Watch the clip on glacier mass balance by the 'Time for Geography' crew and answer the following questions:
What do we rely on glaciers for?
How many tonnes of glacier ice has been lost?
How has that loss impacted the global sea levels?
How does a glacier form? A reminder.
How does a glacier move?
How much does a glacier move a day at its fastest rate?
What are the smaller inputs into the glacial system?
Where does a glacier gain its mass?
Where does a glacier lose its mass?
What is a calving?
What is the equilibrium line?
What happens to the equilibrium line if there is warming temperatures?
What happens to the equilibrium line if there are declining temperatures?
Why do we use the equilibrium line as an indicator of a glaciers health?
What is the glacier mass regime?
Why does a glaciers mass vary throughout the year?
Why do we need to look at a glacier's mass beyond a single year?
Why is it important to understand how glacial systems work?
Activity Three - Mix and Match
You are now beginning to come across lots of subject specific terms that help to describe the changes that occur within a glacial system. To help you to come to grips with these words complete the mix and match activity. Collect the worksheet and either number the terms and then the relevant definition, colour code or grab your scissors and glue to cut everything out and then stick the answers together.
Activity Four - Movement
Glaciers are heavy beasts so how do they move? The movement is essential in carving out the steep sided valleys that glaciers can be found in. Using the clips below draw an annotated digram to explain how glaciers move.
How do glaciers move?
BBC Earth Lab