Chartrand is part of an international research study team that got here at the uninhabited island of Axel Heiberg at the start of one of the most intense summertime warming occasions ever recorded. Their field research focused on the islands Muskox Valley, east of the Muller Ice Cap. Scientists combined air photographs from 1959 with field observations and advanced Light Detection and Ranging (LiDAR) information they collected in 2019 to understand how the Axel Heiberg Island landscape has actually progressed over a 60-year duration.
Flooding from the valley lake, and seasonal melt of the snowpack and ground ice contributes water which coalesces down valley, setting the conditions for coarse sediment transportation and the advancement of channel networks along the valley flooring. “We anticipate that disintegration and sediment transport is sensitive to whether floods occur before or after a period of elevated air temperatures, since this influences the depth to which sediment particle substrates are thawed, and hence results whether the particles are transferred by flood waters.”
” This influence is also affected by the timing, magnitude, and duration of flood occasions, along with whether the underlying sediment particle substrates are frozen, or partly frozen.”
Antero Kukko collecting topographic data utilizing the AkhkaR4DW knapsack mobile laser scanning system which Dr. Kukko designed and developed. Credit: Shawn Chartrand
Research Methodology and Landscape Evolution
Chartrand is part of an international research team that got to the uninhabited island of Axel Heiberg at the start of one of the most intense summer season warming occasions ever tape-recorded. Their field research concentrated on the islands Muskox Valley, east of the Muller Ice Cap. Researchers combined air photographs from 1959 with field observations and state-of-the-art Light Detection and Ranging (LiDAR) data they collected in 2019 to understand how the Axel Heiberg Island landscape has evolved over a 60-year duration.
The Ripple Effects of Warming
” Interconnected physical procedures can deepen river channels and broaden river networks, creating more surface area for heat exchange, which can increase local rates of permafrost thaw,” states study co-author Mark Jellinek, teacher of Earth, Ocean and Atmospheric Sciences at the University of British Columbia. “These cascading effects can boost the release of greenhouse gases in the Arctic as organic soil carbon thaws and the permafrost retreats.”
Using the LiDAR information, the group produced a Digital Elevation Model (DEM) of a 400-meter area of the valley. “Through modeling of how water moves through the landscape, we discovered that flood waters routed through interconnected polygon troughs improves the likelihood of erosion and channel advancement,” says Chartrand.
The Axel Heiberg 2019 group headed into the field for a long day of information collection and hiking. Credit: Mark Jellinek
Impact of Temperature on Flooding
Flooding from the valley lake, and seasonal melt of the snowpack and ground ice contributes water which coalesces down valley, setting the conditions for coarse sediment transportation and the development of channel networks along the valley floor. “We anticipate that erosion and sediment transport is sensitive to whether floods take place before or after a duration of elevated air temperature levels, because this affects the depth to which sediment particle substrates are thawed, and therefore results whether the particles are transferred by flood waters.”
Looking Ahead: Predicting Future Changes
Scientists state the obstacle going forward will be to use this information to produce predictive physical models that help to understand how Arctic river networks will progress over future years marked by both warming and heightening environment irregularity. They indicate included urgency as broadening river networks will carry greater sediment loads along with nutrients and metals into vulnerable watersheds and fisheries with possibly significant repercussions for coastal wildlife, waters, and populations.
Reference: 12 September 2023, Nature Communications.DOI: 10.1038/ s41467-023-40795-9.
The research study group likewise consisted of researchers from the Finnish Geospatial Research Institute, Laboratoire de Planétologie et Géosciences (UMR CNRS 6112), University of Western Ontario, and the Jet Propulsion Laboratory.
Polygons and channel networks on the west side of Axel Heiberg Island near Expedition Fjord. Credit: Shawn Chartrand
Magnified global warming has changed Canadian High Arctic river networks over 60 years, influenced by freeze-thaw cycles and flooding patterns. New research study highlights the urgent need for predictive designs to anticipate future Arctic ecological shifts.
New research study co-led by Simon Fraser University and the University of British Columbia reveals that amplified worldwide warming in the Canadian High Arctic drove a profound shift in the structure of a river network sculpted into a permafrost landscape in only 60 years. Documenting a powerful interaction among climate change, the freeze-thaw dynamics of polygonal ground, and the shipment of surface water by floods in addition to snow and ice melting, the team developed a new view of the physical controls governing the speed and pattern of river channel advancement in these delicate landscapes.
Polygonal Ground and Water Flow
” One of the key processes we determined in the development of stream networks is that their development is affected by the method water flows through fields of approximately 10 meter-wide polygons, created through the freezing and thawing of the soil in Arctic regions,” states Shawn Chartrand, assistant teacher in the School of Environmental Science at Simon Fraser University, and lead author of the research published today (September 12) in the journal Nature Communications.