Amplification of Plunging Flows in Bedrock Canyons
Abstract Bedrock river erosion is driven by channel hydraulics, which are not well understood for complex morphologies. Many bedrock rivers exhibit a constriction‐pool‐widening (CPW) morphology associated with submerged plunging flows. These flows cause velocity profile inversions resulting in high...
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| Format: | Article |
| Language: | English |
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Wiley
2022-06-01
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| Series: | Geophysical Research Letters |
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| Online Access: | https://doi.org/10.1029/2022GL098487 |
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| author | Max Hurson Jeremy G. Venditti Colin D. Rennie Eva Kwoll Kirsti Fairweather Dan R. W. Haught Kyle M. Kusack Michael Church |
| author_facet | Max Hurson Jeremy G. Venditti Colin D. Rennie Eva Kwoll Kirsti Fairweather Dan R. W. Haught Kyle M. Kusack Michael Church |
| author_sort | Max Hurson |
| collection | DOAJ |
| description | Abstract Bedrock river erosion is driven by channel hydraulics, which are not well understood for complex morphologies. Many bedrock rivers exhibit a constriction‐pool‐widening (CPW) morphology associated with submerged plunging flows. These flows cause velocity profile inversions resulting in high velocities near the bed and low velocities on the water surface. The first observations documenting plunging flows were from relatively low discharge, and it is unclear whether they persist during floods. Here we show that plunging flows persist and get stronger at flood discharge, increasing bedrock erosion potential by particle impacts. Flood‐discharge plunging flows contact the bed and maintain high velocities farther through the CPW structure, and evacuate large volumes of sediment from the pools. These reach‐scale processes are not represented in large‐scale landscape evolution models, yet these erosion mechanisms set the pace of landscape evolution, begging for a re‐evaluation of process representation in landscape evolution models. |
| format | Article |
| id | doaj-art-9b90916a716843d9af4a18b6cd5690fe |
| institution | Kabale University |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2022-06-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-9b90916a716843d9af4a18b6cd5690fe2025-01-22T14:38:16ZengWileyGeophysical Research Letters0094-82761944-80072022-06-014912n/an/a10.1029/2022GL098487Amplification of Plunging Flows in Bedrock CanyonsMax Hurson0Jeremy G. Venditti1Colin D. Rennie2Eva Kwoll3Kirsti Fairweather4Dan R. W. Haught5Kyle M. Kusack6Michael Church7Department of Geography Simon Fraser University Burnaby BC CanadaDepartment of Geography Simon Fraser University Burnaby BC CanadaDepartment of Civil Engineering University of Ottawa Ottawa ON CanadaDepartment of Geography University of Victoria Victoria BC CanadaDepartment of Geography Simon Fraser University Burnaby BC CanadaDepartment of Geography Simon Fraser University Burnaby BC CanadaDepartment of Geography Simon Fraser University Burnaby BC CanadaDepartment of Geography University of British Columbia Vancouver BC CanadaAbstract Bedrock river erosion is driven by channel hydraulics, which are not well understood for complex morphologies. Many bedrock rivers exhibit a constriction‐pool‐widening (CPW) morphology associated with submerged plunging flows. These flows cause velocity profile inversions resulting in high velocities near the bed and low velocities on the water surface. The first observations documenting plunging flows were from relatively low discharge, and it is unclear whether they persist during floods. Here we show that plunging flows persist and get stronger at flood discharge, increasing bedrock erosion potential by particle impacts. Flood‐discharge plunging flows contact the bed and maintain high velocities farther through the CPW structure, and evacuate large volumes of sediment from the pools. These reach‐scale processes are not represented in large‐scale landscape evolution models, yet these erosion mechanisms set the pace of landscape evolution, begging for a re‐evaluation of process representation in landscape evolution models.https://doi.org/10.1029/2022GL098487plunging flowsconstriction‐pool‐wideningbedrock riverplunge poolbedrock channel hydraulicsbedrock erosion |
| spellingShingle | Max Hurson Jeremy G. Venditti Colin D. Rennie Eva Kwoll Kirsti Fairweather Dan R. W. Haught Kyle M. Kusack Michael Church Amplification of Plunging Flows in Bedrock Canyons Geophysical Research Letters plunging flows constriction‐pool‐widening bedrock river plunge pool bedrock channel hydraulics bedrock erosion |
| title | Amplification of Plunging Flows in Bedrock Canyons |
| title_full | Amplification of Plunging Flows in Bedrock Canyons |
| title_fullStr | Amplification of Plunging Flows in Bedrock Canyons |
| title_full_unstemmed | Amplification of Plunging Flows in Bedrock Canyons |
| title_short | Amplification of Plunging Flows in Bedrock Canyons |
| title_sort | amplification of plunging flows in bedrock canyons |
| topic | plunging flows constriction‐pool‐widening bedrock river plunge pool bedrock channel hydraulics bedrock erosion |
| url | https://doi.org/10.1029/2022GL098487 |
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