Research and Development

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BSI also conducts research and development primarily in instrumentation and embedded technologies applied to cryospheric research, such as ice-penetrating radars.

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  • Stationary Radar: First Deployment July-September 2014, Yukon. Introduced during topical session at Arctic Change 2014 international meeting in Ottawa.
  • GHz radar for snow and lake ice applications

Articles and publications
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  • Mingo, L., Flowers, G., Crawford, A., Mueller, D., & Bigelow, D. (2020). A stationary impulse-radar system for autonomous deployment in cold and temperate environments. Annals of Glaciology, 61(81), 99-107. doi:10.1017/aog.2020.2
Abstract
Stationary ice-penetrating radar (sIPR) systems can be used to monitor temporal changes in electromagnetically sensitive properties of glaciers and ice sheets. We describe a system intended for autonomous operation in remote glacial environments, and document its performance during deployments in cold and temperate settings. The design is patterned after an existing impulse radar system, with the addition of a fibre-optic link and timing module to control transmitter pulses, a micro-UPS (uninterruptable power supply) to prevent uncontrolled system shutdown and a customized satellite telemetry scheme. Various implementations of the sIPR were deployed on the Kaskawulsh Glacier near an ice-marginal lake in Yukon, Canada, for 44–77 days in summers 2014, 2015 and 2017. Pronounced perturbations to englacial radiostratigraphy were observed commensurate with lake filling and drainage, and are interpreted as changes in englacial water storage. Another sIPR was deployed in 2015–2016 on ice island PII-A-1-f, which originated from the Petermann Glacier in northwest Greenland. This system operated autonomously for almost a year during which changes in thickness of the ice column were clearly detected.
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  • Crawford, A. J., Mueller, D., Crocker, G., Mingo, L., Desjardins, L., Dumont, D., and Babin, M. (2020): Ice island thinning: rates and model calibration with in situ observations from Baffin Bay, Nunavut, The Cryosphere, 14, 1067–1081, doi:/10.5194/tc-14-1067-2020.                     
Abstract
A 130 km2 tabular iceberg calved from Petermann Glacier in northwestern Greenland on 5 August 2012. Subsequent fracturing generated many individual large “ice islands”, including Petermann ice island (PII)-A-1-f, which drifted between Nares Strait and the North Atlantic. Thinning caused by basal and surface ablation increases the likelihood that these ice islands will fracture and disperse further, thereby increasing the risk to marine transport and infrastructure as well as affecting the distribution of freshwater from the polar ice sheets. We use a unique stationary and mobile ice-penetrating radar dataset collected over four campaigns to PII-A-1-f to quantify and contextualize ice island surface and basal ablation rates and calibrate a forced convection basal ablation model. The ice island thinned by 4.7 m over 11 months. The majority of thinning (73 %) resulted from basal ablation, but the volume loss associated with basal ablation was ∼12 times less than that caused by areal reduction (e.g. wave erosion, calving, and fracture). However, localized thinning may have influenced a large fracture event that occurred along a section of ice that was ∼40 m thinner than the remainder of the ice island. The calibration of the basal ablation model, the first known to be conducted with field data, supports assigning the theoretically derived value of 1.2×10−5 m2∕5 s−1/5 ∘C−1 to the model's bulk heat transfer coefficient with the use of an empirically estimated ice–ocean interface temperature. Overall, this work highlights the value of systematically collecting ice island field data for analyzing deterioration processes, assessing their connections to ice island morphology, and adequately developing models for operational and research purposes.
  • ​Briggs, R., Thibault, C., Mingo, L., & King, T. (2020). Usage of UAVs for Surveying and Monitoring Icebergs (Essay). J. Ocean Technol, 15(3), 46-57.
Abstract
Icebergs pose a hazard to shipping and to offshore oil and gas activities. To mitigate and better manage the risks, it is essential to measure, survey, and monitor them. Collecting in-situ measurements and data from icebergs is challenging. Icebergs frequently roll and/ or break-up. A vessel must maintain a safe separation distance from an iceberg. The margin of safety is calculated to be either one iceberg length or twice the height (whichever is estimated to be the larger number) from the iceberg, thus the bigger the iceberg the greater the separation distance. Given this, it is not feasible to place personnel onto icebergs to make direct measurements. All surveying and measuring must be performed from a distance. Remotely operated unmanned aerial vehicles, commonly know as UAVs, can bridge that gap. In this essay, we summarize our investigations over the past four years to develop both the technology and the operational protocols to effectively use UAVs to survey and monitor icebergs in the harsh environment of the North Atlantic.
  • ​Wilson, N., Flowers, G., & Mingo, L. (2014). Mapping and interpretation of bed-reflection power from a surge-type polythermal glacier, Yukon, Canada. Annals of Glaciology, 55(67), 1-8. doi:10.3189/2014AoG67A101
 Abstract
Bed-reflection power (BRP) from ice-penetrating radar has been used to make inferences about subglacial conditions and processes, yet is subject to confounding influences, including englacial attenuation and bed geometry. We use radar data collected in 2008–11 from a polythermal glacier to compute BRP with the aim of relating BRP to basal conditions. We examine the relationship between raw BRP and ice thickness, apparent bed slope and thickness of the englacial scattering layer as a proxy for internal reflection power. We then analyze a corrected form of the BRP with a graph-segmentation algorithm to delineate areas of high and low reflection power. Low corrected BRP values are found near the glacier terminus where the bed is most likely to be cold, while high corrected BRP is found in the region thought to be undergoing a slow surge. We find a spatial correlation between high BRP and high values of subglacial hydraulic upstream area, suggestive of a hydrological control on BRP. Whereas in dominantly cold glaciers BRP seems to distinguish cold from temperate regions of the bed, BRP in  a polythermal glacier with a substantial volume of temperate ice may be a more complex product of thermal and hydrological conditions.
  • Wilson, N.J., G.E. Flowers, L. Mingo. (2013). Comparison of thermal structure and evolution between neighboring subarctic glaciers. Journal of Geophysical Research - Earth Surface, 118, doi:10.1002/jgrf.20096, 1443-1459.​
Abstract
The distribution of cold and temperate ice within glaciers and ice sheets affects processes relevant to englacial and basal hydrology, sliding, and material rheology. Thermal regimes, in turn, are shaped by glacier and ice sheet dynamics, as well as environmental setting. We investigate the thermal structures of two small (<7 km2) neighboring glaciers in the St. Elias Mountains of southwestern Yukon, Canada, using ice-penetrating radar and borehole temperature measurements. Our data reveal polythermal regimes in both glaciers that are strongly influenced by accumulation zone meltwater entrapment, suggesting a climatic control on thermal structure. Differences in hypsometry and glacier dynamics nevertheless result in observed variations in the distribution of temperate ice between the two sites. Experiments with a thermomechanically coupled flow band model corroborate the strong control of meltwater entrapment on thermal structure and suggest a generally minimal role for strain heating. An exception to this occurs where localized basal sliding produces lateral shearing and thus enhanced heat generation. Time-dependent model simulations suggest that the future thermal evolution of the two glaciers may differ, and therefore simple parameterizations of thermal response based on regional climate may not capture realistic variability between individual glaciers. Despite these differences, both glaciers are ultimately expected to become fully cold prior to disappearing under negative mass balance conditions.
  • Mingo, L., & Flowers, G. (2010). An integrated lightweight ice-penetrating radar system. Journal of Glaciology, 56(198), 709-714. doi:10.3189/002214310793146179
Abstract
We describe a portable low-frequency impulse radar system intended for ground-based surveys that employs off-the-shelf hardware integrated with custom-designed software. The hardware comprises a 1–200MHz transmitter, digitizer, computer and GPS receiver, which together weigh 1.5kg. The entire system, including waterproof enclosures and batteries suited for >8hours of continuous operation, weighs <10kg plus the weight of the antenna housing. The system design is flexible, permitting hardware components such as the digitizer or navigation device to be exchanged. The software includes acquisition parameter control, real-time visual ice-depth rendering and data management capabilities using a hierarchical data format. The system described here has been successfully used to sound polythermal ice up to 220m thick in ski-based surveys in the Yukon, Canada, and temperate ice up to 550m thick in machine-based surveys in Iceland.
  • Mingo, L., & Mcclung, D. (1998). Crocus test results for snowpack modeling in two snow climates with respect to avalanche forecasting. Annals of Glaciology, 26, 347-356. doi:10.3189/1998AoG26-1-347-356.​
Abstract
Overall results comparing field observations and Crocus simulations during the winters 1993-94 and 1994-95 in two different climate zones are presented. We present information on: snow depth, snow-temperature profiles, density profiles, liquid-water content profiles and grain metamorphism. Snow profiles illustrating the typical behavior of the model are presented and are shown to illustrate the sensitivity of Crocus to
different mountain climates. Heat-exchange simulation, together with qualitative analysis of meteorological data, give promising results for surface-hoar prediction