Journey to Antarctica: Measuring ice sheet temperatures from space

Summertime in East Antarctica is something to behold. With average temperatures around -20 degrees Fahrenheit, the challenges at the few isolated research stations are comparable to what humans might encounter in long duration deep space missions. A slight breeze can make going outside potentially fatal.

That’s why engineers and scientists at The Ohio State University are thankful to Italian scientist Dr. Marco Brogioni for carrying out a new research project in the frozen desert. The ultimate goal: to measure the Earth’s internal ice sheet temperatures using remote sensing for the first time.

The work to develop new Earth sensing systems is being done in partnership between engineers from Ohio State’s Department of Electrical and Computer Engineering (ECE) and the “Nello Carrara” Institute of Applied Physics (IFAC) of Italy’s National Research Council (CNR). Brogioni's participation is within the framework of a project support by the Italian National Antarctic Research Program, led by Dr. Giovanni Macelloni of IFAC. The team also includes researchers from Ohio State's Byrd Polar and Climate Research Center, School of Earth Sciences and The University of Michigan.

Dr. Joel Johnson

, Ohio State ECE professor and department chair, explained the mission in a presentation at the 2015 IEEE Geoscience and Remote Sensing Society conference held in Milan, Italy this summer. Listen to the full speech in this video HERE.

“This project is about understanding ice sheets, their dynamics, and improving modeling of how ice sheets are expected to evolve over time,” Johnson said. “We’ve heard a lot about different remote sensing methods, but the temperature inside ice sheets is not information that’s been easily available before.”

With NASA funding, researchers at Ohio State’s ElectroScience Laboratory created the new technology to make it happen - a multi-frequency microwave radiometer designed to measure temperatures deep within the ice sheets.

Brogioni began testing a prototype of the system from a tower located at the Concordia Research Station in the Antarctica Plateau throughout December. The team plans to operate the full system in low altitude flights over Greenland in September 2016.

Concordia Station is jointly operated by France (IPEV) and Italy (PNRA), and the help of its logistic team has been fundamental for the success of the program. Progress in these tests could lead to plans for future satellite missions to enable global-scale observations.

Before this technology, Johnson said, the only way to retrieve internal ice sheet temperatures was by drilling into ice sheets sometimes more than 1 mile thick. He said the new ultra-wideband software defined radiometer will use lower frequencies to “see” into the ice sheets, and multiple frequencies then distinguish temperatures at different depths.

“Our goal will be to try and obtain internal ice sheet temperature information and compare it with core-site measurements,” Johnson said. “Our ultimate goal is to try and retrieve the whole profile itself, or at least some model of the profile, throughout the ice sheet.”

He said evidence that microwave radiometers can observe deep into ice sheets is already available from existing satellites currently in orbit. The European Space Agency’s SMOS mission has shown, for example, an “anomaly” in Antarctica where the “temperature” seen by the radiometer drops.

Johnson said this feature coincides with Antarctica’s hidden Lake Vostok, which exists underneath three kilometers of ice. Being able to detect this temperature shift over the lake from space, he said, has provided the motivation to keep developing a more capable multi-frequency radiometer, to obtain additional information on internal temperatures throughout the entire regon.

The research project is currently in the second year of a three-year plan, Johnson said. If all goes well, the tests in Antarctica will serve as a significant milestone. 

The team will assess the Antarctic results through early 2016, and prepare for the Greenland flights in the following months.

“We hope to demonstrate successful measurement of internal temperatures that will lead to future more-extensive deployments,” Johnson said.

Meanwhile, Brogioni continues to report from the Concordia Research Station. He documents his time at Concordia in a blog for the European Space Agency’s Campaign Earth: http://blogs.esa.int/campaignearth/2015/12/03/battling-the-antarctic-wind/

In his blog, Brogioni describes drifting snow burying research shelters, dangerous cold and issues with adapting to high altitudes. Through his efforts, the team’s system is acquiring important data to test the temperature measurement concept. Data retrieved from the subsurface of the ice allows for more stable and accurate knowledge about the evolution of temperatures in this region.

Brogioni said understanding the trends of energy in Antarctica could help monitor the global warming process. Such findings will also contribute to future reports on climate change and be useful for recommendations on global warming to international policy makers.

To learn more about ECE climate research related to Johnson’s team, read about SMAP and Navigating the Noise.