Monitoring the Variation in Ice-Cover Characteristics of the Slave River, Canada Using RADARSAT-2 Data—A Case Study

Abstract

Abstract:The winter regime of river-ice covers in high northern latitude regions is often a determining factor in the management of water resources, conservation of aquatic ecosystems and preservation of traditional and cultural lifestyles of local peoples. As ground-based monitoring of river-ice regimes in high northern latitudes is expensive and restricted to a few locations due to limited accessibility to most places along rivers from shorelines, remote sensing techniques are a suitable approach for monitoring. This study developed a RADARSAT-2 based method to monitor the spatio-temporal variation of ice covers, as well as ice types during the freeze-up period, along the main channel of the Slave River Delta in the Northwest Territories of Canada. The spatio-temporal variation of ice covers along the river was analyzed using the backscatter-based coefficient of variation (CV) in the 2013-2014 and 2014-2015 winters. As a consequence of weather and flow conditions, the ice cover in the 2013-2014 winter had the higher variation than the 2014-2015 winter, particularly in the potential areas of flooded/cracked ice covers. The river sections near active channels (e.g., Middle Channel and Nagle Channel), Big Eddy, and Great Slave Lake also yielded higher intra-annual variation of ice cover characteristics during the winters. With the inclusion of backscatter and texture analysis from RADARSAT-2 data, four water and ice cover classes consisting of open water, thermal ice, juxtaposed ice, and consolidated ice, were discriminated in the images acquired between November and March in both the studied winters. In addition to river geomorphology and climatic conditions such as river width, sinuosity or air temperature, the fluctuation of water flows during the winter has a significant impact on the variation of OPEN ACCESS Remote Sens. 2015, 7 13665 ice cover as well as the formation of different ice types in the Slave River. The RADARSAT-2 based monitoring algorithm can also be applied to other river systems in high latitude ecosystems to annually monitor their river-ice variation and formation during the freeze-up and ice cover progression period.

The Impact of Cumulative Negative Air Temperature Degree-Days on the Appearance of Ice Cover on a River in Relation to Atmospheric Circulation

“…Monitoring of the course and structure of ice phenomena on rivers makes it easier to forecast climate changes, and allows us to determine whether any given climatic tendency is permanent [34][35][36][37]. The ice cover occurs less frequently than the remaining phases of the icing cycle, while factors conducive to its formation are frosty winters and the longer-term persistence of negative air temperatures.…”

Performance evaluation of quad-pol data compare to dual-pol SAR data for river ice classification

“…The research conducted on river ice analysis with SAR data has taken several directions: study of the values of backscatter coefficients for different types of ice cover (Gherboudj, Bernier, & Leconte, 2010); automatic algorithms for ice types classification (Chu, Das, & Lindenschmidt, 2015;Chu & Lindenschmidt, 2016;Gauthier, Tremblay, Bernier, & Furgal, 2010;Mermoz, Allain, Bernier, Pottier, & Gherboudj, 2009); study of ice thickness (Kämäri, Alho, Colpaert, & Lotsari, 2017;Mermoz et al, 2014). However, few studies are found that examine how SAR data parametersfrequency, polarization and incidence angleinfluence the possibility of detecting specific ice types.…”

RIVICE—A Non-Proprietary, Open-Source, One-Dimensional River-Ice Model

“…RIVICE can also simulate the flow dynamics for an ice-covered river by increasing the wetted perimeter to include the width of the underside of the cover. For a solid ice cover, the roughness coefficient now becomes a composite value nc of both the bed and ice roughness coefficients, nb and ni respectively: (2) nb is assumed constant for all in-stream hydraulic conditions of a river reach. For ice covers formed by ice rubble or slush the roughness n can be set as a function of ice thickness h through a relationship established by Nezhikhovskiy [30]:…”

“…Rubble or slush ice also has the potential to jam and dam up a river section, causing even more backwater staging and river banks and levees to overflow and flood the surrounding floodplain. From an ecological perspective, many floodplain and wetland ecosystems require such periodic flooding for their replenishment of moisture, sediment and nutrients, especially in perched ponds and lakes of inland deltas such as, for example in Canada, the Peace-Athabasca Delta in Alberta [1], the Slave River Delta in the Northwest Territories [2,3] and the Saskatchewan River Delta along the Saskatchewan/Manitoba boundary [4,5]. However, ice jams and the flooding they induce can pose threats to, and wreak damage on, many communities located along these rivers.…”