A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Spatial variation of river-ice thickness in a meandering river
Tekijät: Maria Kämäri, Petteri Alho, Alfred Colpaert, Eliisa Lotsari
Kustantaja: ELSEVIER SCIENCE BV
Julkaisuvuosi: 2017
Journal: Cold Regions Science and Technology
Tietokannassa oleva lehden nimi: COLD REGIONS SCIENCE AND TECHNOLOGY
Lehden akronyymi: COLD REG SCI TECHNOL
Vuosikerta: 137
Aloitussivu: 17
Lopetussivu: 29
Sivujen määrä: 13
ISSN: 0165-232X
eISSN: 1872-7441
DOI: https://doi.org/10.1016/j.coldregions.2017.01.009(external)
Tiivistelmä
The spatial variation of river -ice thickness in three contiguous meandering bends was determined via ground penetrating radar technology and traditional borehole measurements. Applying high -frequency GPR enables detailed surveying of the variation in river -Ice thickness and the boundary of floating and grounded (i.e., bottom fast) ice in a relatively large area. Extensive verification of river -ice thickness based on GPR profiling was performed by comparing the radar data with ground truth ice thickness measurements. This revealed that the GPR method is suitable for river -ice thickness calculation with a mean absolute error of +/- 3 cm, equivalent to 5% mean percentage error in the case of 50 -centimeter -thick ice, although snow cover on top of the ice or a possibly non -homogeneous ice surface reduces GPR measurement accuracy and the usability of the method for detailed ice -thickness measurements. The ice -thickness variation in a meandering river was observed to be quite large, with the maximum difference of 32 cm in mean ice thickness between cross sections. However, the observed mean ice thickness yielded a reasonable match with the theoretical mean thickness calculated with a widely used analytical ice -thickness growth equation. The vertically averaged flow velocities measured with an acoustic Doppler current profiler and bottom depths were surveyed from 148 boreholes, which enables discussing the influence of flow velocity and river morphology on the ice thickness's Variation. (C) 2017 Elsevier B.V. All rights reserved.
The spatial variation of river -ice thickness in three contiguous meandering bends was determined via ground penetrating radar technology and traditional borehole measurements. Applying high -frequency GPR enables detailed surveying of the variation in river -Ice thickness and the boundary of floating and grounded (i.e., bottom fast) ice in a relatively large area. Extensive verification of river -ice thickness based on GPR profiling was performed by comparing the radar data with ground truth ice thickness measurements. This revealed that the GPR method is suitable for river -ice thickness calculation with a mean absolute error of +/- 3 cm, equivalent to 5% mean percentage error in the case of 50 -centimeter -thick ice, although snow cover on top of the ice or a possibly non -homogeneous ice surface reduces GPR measurement accuracy and the usability of the method for detailed ice -thickness measurements. The ice -thickness variation in a meandering river was observed to be quite large, with the maximum difference of 32 cm in mean ice thickness between cross sections. However, the observed mean ice thickness yielded a reasonable match with the theoretical mean thickness calculated with a widely used analytical ice -thickness growth equation. The vertically averaged flow velocities measured with an acoustic Doppler current profiler and bottom depths were surveyed from 148 boreholes, which enables discussing the influence of flow velocity and river morphology on the ice thickness's Variation. (C) 2017 Elsevier B.V. All rights reserved.