What’s a Mathematician Doing at SkyTruth?

Alice Foster discovered her love for geology at Brown University, and meandered onto SkyTruth’s path.

My name is Alice Foster, and I started as an intern at SkyTruth this past January. But my journey to SkyTruth was a bit unexpected. I am currently studying applied mathematics at Brown University. And until recently, I was somewhat unenthusiastic about science, although I was interested in conservation issues.

Then, in search of an introductory environmental studies class at my first academic fair, I ended up talking to a professor at the Department of Earth, Environmental, and Planetary Sciences table. She convinced me to try out her class, which she said offered a good foundation for understanding environmental issues. In the opening lecture, I was a bit disappointed to learn that the class was about geology; lacking any understanding of the subject beyond an earthquake project in seventh grade, I associated the word with something vaguely boring and irrelevant. But after a few minutes, I was hooked. I found it beautiful to understand how mountain ranges and canyons and plains come into being, and to try to wrap my head around the massive time scales on which geological processes take place. Learning about crystal deformation at a molecular level was fascinating because it could explain how an entire glacier moves. Everything seemed to fit together. Over the course of the semester we applied physics and chemistry, satellite and seismic imagery, and logic to solve Earth’s riddles. 

One of my favorite topics covered in that class was meandering rivers, a concept I identified with. A meander forms a curve in a river: fast-moving water wears away at the outer bank, while sediment transported by slower-moving water amasses at the inner edge, creating a point bar. This process of erosion and deposition makes the bends bendier and the river wander. 

If you look at outcrops on the side of a road, you might spot evidence of ancient meandering rivers. A fast-moving river can transport and deposit large pebbles in its channel. When the water changes course, the former channel becomes part of the river’s floodplain. At times, the river overwhelms its banks and leaves behind sand and clay to overlay the old layer. Some years later, the channel might shift again and deposit larger grains on top of the fine particles. In the rock record, these deposits can appear as beds of shale interspersed with conglomerates.

Alice camping with friends. Photo by Ailita Eddy.

The summer after I took this geology class, I encountered a magnificent meandering river near a farm I worked at in Iowa. Tall trees with lush foliage grew on one bank; a cow pasture bordered the other. I liked to walk down the road to a bridge overlooking the river. I imagined it all playing out: water flowing around the outer edge and loosening soil from the steep bank, bits of rock bouncing chaotically along the riverbed, and the inner bank growing thick with silt. In millions of years, the vestiges of the river might lie deep beneath the ground, compacted, cemented, and turned to stone. 

Since then, my interest in geology and climate science, combined with my love for mathematics, has informed my meandering career exploration. This semester, I decided to take a break from school and homework and experience new things. I wanted to intern at SkyTruth because SkyTruth’s work combines many of my greatest passions, and because I felt excited about contributing to work that could benefit others. It is amazing to see up close how SkyTruth uses geospatial technology to solve tangible problems. I get to think about math and geology while engaging with immediate conservation issues around the world. 

Right now I am working on monitoring bilge dumping in oceans around the Arabian Peninsula, Africa, and Brazil. I am also working with SkyTruth staff to digitize natural gas well pads for a machine learning model. This model will allow SkyTruth to automatically identify well pads in Alaska and Patagonia.

As an intern I have had the chance to learn how to create maps in QGIS and how to program in Google Earth Engine. QGIS is a geographic information system application that can be used to analyze and visualize geospatial data such as satellite imagery or a ship’s track across the ocean. I have also gotten to reflect on what I might want my career to look like. I love getting to be part of a welcoming, supportive, super knowledgeable, all-around wonderful group of people pursuing new projects and ideas. Though I am unsure of my path, this is the kind of environment I will look for as I embark on my career.

Alice made this on a letterpress printer using a linoleum carving block and metal type. “Wild Geese” is one of her favorite poems. She wanted to create an image having to do with the refuge one can find in the natural world. Credit: Alice Foster