Research and Development
BSI also conducts research and development primarily in instrumentation and embedded technologies applied to cryospheric research, such as ice-penetrating radars.
- GHz radar for snow and lake ice applications
Articles and publications
- Wilson, N. J., Flowers, G. E. , Mingo, L. Mapping and interpretation of bed-reflection power from a surge-type polythermal glacier, Yukon, Canada. Annals of Glaciology, 55 (67), 2014, International Glaciology Society, (Also here).
- 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., Flowers, G. E. , Mingo, L. Comparison of thermal structure and evolution between neighboring subarctic glaciers. Journal Of Geophysical Research, Earth Surface, Vol. 118, Issue 2, 2013.
- 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. E. An integrated lightweight ice-penetrating radar system. Journal Of Glaciology, Vol.56 No198, 2010. International Glaciology Society.
- 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, D.M. McClung. Crocus test results for snowpack modeling in two snow climates with respect to avalanche forecasting. Annals of Glaciology, Vol. 26. pp 347-356, 1998. International Glaciology Society.
- 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