Three CReSIS graduate students have received fellowships from the prestigious NASA Earth and Space Science Fellowship (NESSF) Program.

Jerome Mitchell and Theresa Stumpf were recently awarded the fellowship and Emily Arnold’s fellowship, which was first awarded last year, was renewed for another year. Fewer than 17 percent of all applicants were selected for the Earth Science research award this year.

The fellowship provides $30,000 to recipients, which includes funds for living expenses, research materials, travel funds and university expenses.

Mitchell, a Graduate Research Assistant (GRA) at Indiana University, is a Ph.D. student in Computer Science. The fellowship will support Mitchell’s research project, called “Developing Machine Learning Algorithms to Access Bedrock and Internal Layers in Polar Radar Imagery.”

CReSIS collects massive amounts of data from a number of different sensors to detect changes in the ice sheets. After this data is collected, the echogram layers have to be manually identified to determine ice thickness or create accumulation maps. This creates a lot of additional work for researchers. Mitchell’s research project is addressing this problem.

“My proposed research is to develop and apply learning algorithms in order to automatically detect these layers in polar radar imagery,” said Mitchell.

Mitchell earned a bachelor’s in Computer Science from Elizabeth City State University and a master’s from the University of Kansas. He’s pursuing his doctorate in Computer Science, focusing on high performance computing. Mitchell has long been a part of CReSIS, attending three CReSIS partner institutions, teaching workshops and contributing to field work.

Stumpf is a GRA at the University of Kansas, where she is a Ph.D. student studying Electrical Engineering and Computer Science. Her project is entitled “Ultra-Wideband, Wide-Swath Radar Imaging of the Ice-Bed Interface for Generating Fine Resolution Bed Topography and Quantifying Basal Conditions.”

“My research aims to enhance the scientific utility of an Ultra-Wideband (UWB) ice sounder/imager being developed by CReSIS,” said Stumpf.

“I am seeking to enhance the scientific utility of this sensor by developing a wide-swath imaging mode tailored for UWB signals that I will use to generate swath image products of bed topography and basal conditions at the ice-bed interface.”

Basal conditions tell researchers what is happening at the bed, such as whether or not it is frozen or wet.

The UWB is important for two main reasons: 1) It can make topographic bed measurements with finer resolution, which provides more detail and helps researchers determine basal conditions; and 2) The large cross-track array helps resolve “ambiguous echoes” in the cross-track direction.

“Large arrays are needed to form narrow beams that we can use to map the bed in finer detail,” said Stumpf.

Stumpf began at CReSIS as an REU student.

Arnold recently had her NASA fellowship renewed for another year after being awarded the fellowship last year. She is currently a GRA at the University of Kansas and a Ph.D. student in Aerospace Engineering.

“My research is developing and improving airborne remote-sensing platforms for cryospheric surveying,” said Arnold.

The project is titled “Enhancing Airborne Remote Sensing Radar to Provide Higher Quality Ice Sheet Measurements Used for Predicting Sea-Level Rise.”

The first two years of Arnold’s Ph.D. program were spent as the lead designer on the array fairings for the DC-8 and P-3 aircrafts. Fairings are the aerodynamic structures that house and support the antenna array on an aircraft. Since designing these fairings, Arnold has been working on improvements.

“I have worked to improve current and future airborne radars used for sounding ice sheets by identifying antenna-array performance degradation,” said Arnold.

Each of the NESSF recipients will be funded for the next year. After the first year of the program, fellowships may be renewed for another two years. The fellowships are in large part thanks to the opportunities provided to students at CReSIS, according to students.

“CReSIS is really special because it gives graduate students research opportunities that are extremely unique,” said Stumpf. “I'm really lucky and so thankful for all of the experiences that I have had here.”