Mapping the last frontier

Author: Kutalmis Saylam, June 2016 

Alaska is the least densely populated yet largest state in the United States. Well-known for its diverse landscape and cold weather, travelling can be difficult during winter months. In the northern parts of the state, where tundra is vast and winter climate is harsh, use of ice roads are popular and necessary for transporting resources. Because the state has more than 3 million lakes that are larger than 20 acres in size, a clear understanding of the landscape is required to best determine where these roads could safely and sustainably be built. The Bureau of Economic Geology (the Bureau), a research unit at the University of Texas at Austin, set out to map a portion of this wild frontier and provide a better understanding of the local habitat, using the Leica Chiroptera airborne LiDAR system to survey the Alaskan Northern Slope.

A unique landscape

The Alaskan North Slope micro-topography supports various potential fish habitat water bodies and wetland areas within the arctic tundra environment. Shallow thaw lakes, less than 2 metres deep, in general, are a major component of the tundra landscape of the area, where they compose approximately 20 percent of the total area. They are completely ice-free only a few weeks in a calendar year, so we scheduled our field trip accordingly, beginning in mid-July and ending in early August.

The lakes’ depth, ice growth and decay determine whether they are suitable habitat for wildlife and aquatic fauna, as well as for industrial development. Ice accumulation is assumed to be 1.5 to 2 m thick in this area, and liquid water most likely lies below in the central basins of these lakes if the water is deeper than 2 m. Survey findings were particularly important because they would reveal lakes deeper than 2 m, suitable for building ice roads, but with potential fish habitat. Findings were also expected to assist other environmental and hydrological assessments in the area.

“With thousands of lakes – with varying turbidity levels – scattered throughout the survey area and challenging weather conditions that limited the airborne survey activities, this was certainly not an easy task,” said John Andrews, a research scientist from the Bureau, who was responsible for ground truthing and overall logistical support. “With airborne LiDAR surveying, though, we were able to obtain very detailed and precise topographic and bathymetric data in areas where traditional survey methods would not be feasible.”

Explore next chapter: Flying with double the scanning power

Story: Mapping the last frontier
Chapter 1: A unique landscape
Chapter 2: Flying with double the scanning power
Chapter 3: Faster, more accurate data analysis