HF/VHF Radar Sounding of Ice from Manned and Unmanned Airborne Platforms

Geosciences

John Sonntag¹  Emily Arnold²  Bailey Miller²  Shawn Keshmiri²  Mark Ewing²  Rick Hale²  Aaron Blevins²  Fernando Rodriguez-Morales³  Akhilesh Mishra³  Teja Karidi³  John Paden³  Carl Leuschen³  Ali Mahmood³  Stephen Yan⁴ 

[1] AECOM Corporation, Greenbelt, MD 20782, USA;Aerospace Engineering Department, University of Kansas, Lawrence, KS 66045, USA;Center for Remote Sensing of Ice Sheets, University of Kansas. Lawrence, KS 66045, USA;Department of Electrical and Computer Engineering, University of Alabama, Tuscaloosa, AL 35487, USA;

关键词: remote sensing;    ice sheets;    glaciers;    radar;    unmanned aircraft system (UAS);    synthetic aperture radar (SAR);   

DOI  :  10.3390/geosciences8050182

来源: DOAJ

【 摘 要 】

Ice thickness and bed topography of fast-flowing outlet glaciers are large sources of uncertainty for the current ice sheet models used to predict future contributions to sea-level rise. Due to a lack of coverage and difficulty in sounding and imaging with ice-penetrating radars, these regions remain poorly constrained in models. Increases in off-nadir scattering due to the highly crevassed surfaces, volumetric scattering (due to debris and/or pockets of liquid water), and signal attenuation (due to warmer ice near the bottom) are all impediments in detecting bed-echoes. A set of high-frequency (HF)/very high-frequency (VHF) radars operating at 14 MHz and 30–35 MHz were developed at the University of Kansas to sound temperate ice and outlet glaciers. We have deployed these radars on a small unmanned aircraft system (UAS) and a DHC-6 Twin Otter. For both installations, the system utilized a dipole antenna oriented in the cross-track direction, providing some performance advantages over other temperate ice sounders operating at lower frequencies. In this paper, we describe the platform-sensor systems, field operations, data-processing techniques, and preliminary results. We also compare our results with data from other ice-sounding radars that operate at frequencies both above (Center for Remote Sensing of Ice Sheets (CReSIS) Multichannel Coherent Depth Sounder (MCoRDS)) and below (Jet Propulsion Laboratory (JPL) Warm Ice Sounding Explorer (WISE)) our HF/VHF system. During field campaigns, both unmanned and manned platforms flew closely spaced parallel and repeat flight lines. We examine these data sets to determine image coherency between flight lines and discuss the feasibility of forming 2D synthetic apertures by using such a mission approach.

【 授权许可】

Unknown