Welcome to Module 7
Glaciers, Ice, and Permafrost—Yosemite, Glacier, and Bear Meadows

Although not quite as large as minivans, musk oxen have better cornering and can surely accelerate rapidly. This picture shows musk oxen thundering across the tundra of east Greenland. If you had been in central Pennsylvania's Bear Meadows with a camera 20,000 years ago, you might have taken this picture--tundra and musk oxen very similar to these existed in Pennsylvania and adjacent states back then, while an ice sheet even bigger than modern Greenland's loomed just to the north. How do we know that the ice came and went, and what caused the changes? Look both ways for musk oxen or minivans, depending on where and when you are, and let's go see.
When we try to pick out anything by itself, we find it hitched to everything else in the Universe.
— John Muir, My First Summer in the Sierra, 1911, p. 110
Learning Objectives
- Recognize that glaciers behave in predictable ways because of physical processes that are shared with other materials, including pancake batter spreading on a waffle iron.
- Understand how glaciers uniquely make certain features that are found today in many places without glaciers, suggesting that ice ages with larger glaciers occurred in the past.
- Discuss how this ice-age hypothesis leads to many predictions that have been tested and found to be correct, giving very strong confidence that ice ages did occur, and helping us understand how and why the ice ages occurred.
What to do for Module 7?
You will have one week to complete Module 7. See the course calendar for specific due dates.
- Take the RockOn #7 Quiz
- Take the StudentsSpeak #8 Survey
- Submit Exercise #3
- Begin working on Exercise #4
Questions?
If you have any questions, send an email via Canvas, to ALL the Teachers and TAs. To do this, add each teacher individually in the “To” line of your email. By adding all the teachers, the TAs will be included. Failure to email ALL the teachers may result in a delayed or missed response. For detailed directions on how to do this, see How to send an email in GEOSC 10 in the Important Information module.

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