A low power consumption radar system for measuring ice thickness and snow/firn accumulation in Antarctica

Abstract

ABSTRACT. In order to measure total ice thickness and surface snow accumulation in Antarctica, we have designed and built a surveying system comprising two types of radar. This system is aimed at having low power consumption, low weight/volume and low construction cost. The system has a pulsecompression radar to measure ice thickness, and a frequency-modulated continuous wave (FM-CW) radar designed to measure hundreds of meters of surface snow/firn layers with high resolution. The pulsecompression radar operates at 155 MHz, 20 MHz of bandwidth; and the FM-CW radar operates from 550 to 900 MHz. The system was tested in December 2010 at Union Glacier (79846 0 S, 83824 0 W), West Antarctica, during an oversnow campaign, where Union and other nearby glaciers (Schanz, Schneider and Balish) were covered through 82 km of track. Ice thickness of 1540 m and snow/firn thickness of 120 m were detected in the area. The collected data allowed the subglacial topography, internal ice structure, isochronous and the snow/ice boundary layer to be detected. Here we describe radar electronics, their main features and some of the results obtained during the first test campaign. Further improvements will focus on the adaptation of the system to be implemented on board airplane platforms.

Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet

“…6), it is possible to see the shallowest ice at the Gifford Peaks pass (passage), with a thickness between 45 and 140 m obtained by the low-gain channel of the pulse compression radar. This profile is not visible in the high-gain channel, due to set-up constraints on this system (Uribe et al, 2014).…”

“…A frequency-modulated continuous-wave (FM-CW) radar also designed by Uribe et al (2014) was used to measure surface snow and ice layering to a depth of 450 m with a high vertical resolution (1 m). This radar works at a frequency from 550 to 900 MHz using two separated log periodic antennae for the transmitter and receiver.…”

“…A Coherent pulse compression radar depth sounder designed at Centro de Estudios Científicos CECs (Uribe et al, 2014) was used to measure ice thickness. The radar operates at a central frequency of 155 MHz, a maximum of 10 kHz of pulse repetition frequency (PRF), a bandwidth of 20 MHz and peak power of 200 W. Yagi antennae were used for both the transmitter and the receiver.…”

Historical surface mass balance from a frequency-modulated continuous-wave (FMCW) radar survey from Zhongshan station to Dome A

“…Yamaguchi and others, 1992). This radar architecture has a higher resolution than a conventional pulsed radar, but the measurement range is smaller, so these two radar types can be combined to exploit each system's advantages (Uribe and others, 2014).…”

Descubrimiento del Lago Subglacial CECS en Antártica Occidental

“…Durante esta travesía fue descubierto un lago subglacial, que posteriormente fue nombrado Lago CECs. La detección fue realizada mediante radio eco sondaje, empleando un radar desarrollado en el CECs (Uribe et al, 2014). El lago está ubicado al sur-oeste de los montes Ellsworth, justo en la divisioria entre el Glacier Minnesota (MIN) y la Corriente de Hielo Institute (IIS), como puede verse en la Figura 3.…”