Developing and Testing Physically Based Triggering Thresholds for Runoff‐Generated Debris Flows
AffiliationUniv Arizona, Dept Geosci
MetadataShow full item record
PublisherAMER GEOPHYSICAL UNION
CitationTang, H., McGuire, L. A., Rengers, F. K., Kean, J. W., Staley, D. M., & Smith, J. B. ( 2019). Developing and testing physically based triggering thresholds for runoff‐generated debris flows. Geophysical Research Letters, 46, 8830– 8839. https://doi.org/10.1029/2019GL083623
JournalGEOPHYSICAL RESEARCH LETTERS
Rights©2019. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractRunoff in steep channels is capable of transitioning into debris flows with hazardous implications for downstream communities and infrastructure, particularly in alpine landscapes with minimal vegetation and areas recently disturbed by wildfire. Here, we derive thresholds for the initiation of runoff-generated debris flows based on critical values of dimensionless discharge and Shields stress. These thresholds are derived by using a numerical model to estimate the hydrodynamic conditions coinciding with the timing of debris flow activity in a recently burned basin. A benefit of hydrodynamic thresholds is that they can be used to assess debris flow likelihood based on measurable hydrologic and geomorphic parameters and therefore provide more universal criteria for quantifying the runoff-to-debris flow transition in landscape evolution studies and hazard assessments. We then demonstrate how hydrodynamic thresholds can be used to estimate rainfall intensity-duration thresholds for runoff-generated debris flows without the need for historic debris flow observations.
NoteOpen access article
VersionFinal published version
SponsorsU.S. Geological Survey (USGS) Landslide Hazards ProgramUnited States Geological Survey