Years ago, I moved to a tiny town in Alaska called Skagway. At the time, I didn’t know what career I wanted to pursue. I felt like everyone around me knew what they were going to do: be a teacher, a fisher, a doctor. But I had no idea what I was going to do. I didn’t know that I would become the scientist I am todaya geographer and glaciologist studying glaciers around the world!

When I was young, I had never met a scientist, let alone a female scientist. I didn’t know that science was just as much an option for me as it is an option for all girls and boys worldwide. Growing up, my dad always told me that if I focused on what I loved, a career would follow. I loved the outdoors. So, I moved to Skagway to work outside. It was there I fell in love with glaciers. A glacier is a moving river of ice that flows over Earth’s surface. The coastal mountains surrounding Skagway are full of them. The valley where Skagway sits was even made by a glacier! It’s called a fjord, a valley carved by a glacier long ago that is filled in by the sea. 

Skagway, Alaska, is in a valley made by a glacier long ago.

This is an aerial view of Hoffellsjökull, a glacier in Iceland.

Ever tasted a glacier? When I take students to see glaciers, it’s a fun part of the tour.

Glacier Formation

Today, the reason Skagway is surrounded by glaciers is because, for a long time, it had the perfect ingredients needed to grow glaciers: snow, cold temperatures, and time. If even one of those ingredients is missing, a glacier cannot grow. All three ingredients work together. Snow falls and stacks up. Yearround cold temperatures keep that stacked snow from melting. Over time, the snow keeps stacking up until it is hundreds of meters thick. By then, all that snow has turned into glacier ice.

How? Close your eyes and imagine a single snowflake. It doesn’t weigh very much, but now imagine millions and millions of snowflakes stacked on top of each other. Imagine what happens to that single snowflake at the bottom. With the pressure and weight of all the other snow, that single snowflake squishes down into something called “firn.” Over decades, firn compresses into dense glacier ice!

Glacial ice is very hard. So hard that, when a glacier moves over the land, it can scrape and smooth rockjust like sandpaper does to wood.