Name: Evan James Gowan

Position: PhD Student

Research School of Earth Sciences

the Australian National University

Area of study: Geophysics

Project: Ice sheet history of North America during the last glaciation

What does that mean?

Many parts of the world at high latitude, such as North America, were covered in thick sheets of ice periodically during the past 2.5 million years. Ice grew and retreated in these areas largely as a result of long term changes in the earth’s orbit, which changed the duration of the seasons, and as a result changed the distribution of precipitation, and the balance between melting and accumulation of snow. In North America, the ice sheet that covered most of Canada and parts of the United States reached its maximum extent about 20,000 years ago. After this, the ice started to melt, and by 6000 years ago, was completely gone. When these ice sheets existed, sea level dropped dramatically lower than present. The weight of the ice sheet also pressed down on the land in North America, and due to the viscous nature of the rocks deep within the Earth, there is a delayed relaxation back to pre-glacial topography. At present, Hudson Bay is rising at a rate in excess of 1 cm per year as result of the relaxation. By creating a model of the amount of ice in North America during the last glaciation, we can determine how much it influenced sea level and how it affected the geography of the glaciated area.

How did I get here?

The village near where I grew up (in Canada) was built upon a massive beach that formed during the retreat of the ice sheet. When I was a kid, I always wondered “What could have created this massive beach?” With my PhD project, I can finally answer this question. It might seem strange to come all the way to Australia to study a problem relating to ice and Canada, but given the expertise at RSES, it was a logical choice.

Where will I go?

I always get asked this question, and I cannot answer that at this point, with well over a year left in my PhD. Four years ago, I was trudging through two meters of snow in eastern Canada setting up geophysical equipment. Three years ago, I was testing electronics for a mining company. Two years ago, I was planning a trip to northern Canada. Life can take many unexpected turns, but I enjoy what I am doing now, and I always encourage everyone to follow their dreams.