The University of Cambridge conducted detailed measurements of the ice characteristics on the Greenland ice sheet.
Ice work: Glacier temperature A project led by the Scott Polar Institute of Cambridge University uses fiber-optic sensors to collect new ice temperature data on Greenland glaciers.
According to the team, the results of the study were published in "Science Advances" and represent the most detailed measurement of ice properties on the Greenland ice sheet ever.
They also represent the first use of fiber optic distributed temperature sensing (DTS) on the Greenland ice sheet, installed in a 1,043-meter deep borehole.
Distributed sensing allows spatially resolved measurements of physical properties (temperature in this case) along the entire length of a continuous optical fiber, rather than discrete data from physically separate measurement devices that traditional temperature measurement methods would produce.
"We usually make measurements inside the ice sheet by connecting the sensor to a cable. We put the cable into the borehole, but the observations we have made so far have not given us a complete picture of what is happening. Understand," said from Poul Christoffersen. Scott Polar Institute.
"The more accurate the data we can collect, the clearer we can portray this picture, which in turn will help us make more accurate predictions about the future of the ice sheet."
The new data forms part of a European respondent project to conduct hot water drilling on the Sermeq Kujalleq Glacier to improve understanding of the evolution of the Greenland ice sheet ice flow and employ multiple complementary technology platforms.
Distributed fiber optic sensing enables Responder to combine temperature information with data related to the physical underground movement of ice collected simultaneously through distributed acoustic sensing (DAS). ETH Zurich used DAS to monitor the glacier movement of the Rhone Glacier in Switzerland in 2020. The detector is located under the snow surface and provides new data on the dynamics of glacier movement.
“Fiber optic sensing can measure the entire borehole depth of 1 km in a distributed manner, with spatial accuracy ranging from 0.5 meters (DTS) to 10 meters (DAS),” Responder commented on its project site.
"Therefore, parts of the depth profile can be inspected in great detail, otherwise these parts will be inspected in great detail. The rapid development of fiber optic sensing in the past decade means that this increase in spatial resolution will not compromise the accuracy of the measurement. . In many cases it has been improved."
The transformative potential of high-resolution DTS in glacier research
The project uses Silixa's commercial DTS platform, which, according to the supplier, is currently the highest performance rugged distributed temperature sensor on the market.
"The DTS system consists of Silixa XT-DTS, armored cable jacket optical fiber and thermistor for calibration purposes," the project said in its published paper. "When a laser pulse is transmitted through an optical fiber, it works by measuring the temperature-sensitive components (Stokes and anti-Stokes wavelengths) and propagation time of Raman backscatter."
Data from the optical fiber system shows that the deformation and temperature of ice, both in the vertical direction of the borehole profile and in the space of the glacier catchment area, show greater inhomogeneities than previously thought. This is valuable information for understanding glacier movement and why the Greenland ice sheet loses mass quickly.
According to the research team, the results also proved "the transformative potential of high-resolution DTS in the field of glacier thermodynamics."
Bryn Hubbard, a project partner at Aberystwyth University, commented: "This technology is a major advancement in our ability to record spatial changes in ice temperature at long distances and at very high resolution."