loading page

A comprehensive process-based model for Arctic coastal erosion
  • Mohammad Akhsanul Islam,
  • Raed Lubbad
Mohammad Akhsanul Islam
Norwegian University of Science and Technology

Corresponding Author:[email protected]

Author Profile
Raed Lubbad
Norwegian University of Science and Technology
Author Profile

Abstract

In recent years, various models have been developed to describe Arctic coastal erosion. Many models are process-based, simulating multiple physical processes and combining them interactively to resemble Arctic coastal erosion. One limitation of the current process-based models is the difficulties in including the hydrodynamic forces. The morphological changes by the hydrodynamics are either simplified or simulated by some empirical relation. The reason for excluding detailed hydrodynamic forcing is the absence of thermal energy conservation in the systems of equations inside the available software. Most hydrodynamic models are designed considering the warmer climate, where waves, tides and storm surges cause changes in morphology. The available models cannot be applied where permafrost is a significant environmental parameter. This paper explains a methodology that allows us to use the models designed for warmer climates to simulate Arctic coastal erosion. The open-source software XBeach is used to simulate the waves, sediment transport and morphological changes. We developed different submodules for the processes related to permafrost thawing-freezing, slumping, wave-cut niche, bluff failure, etc. The submodules are coupled with the XBeach following a workflow where ice concentration, storm surge and bluff collapse work as an on-off switch. The submodules communicate with each other at three-hour intervals. The input parameters of the model are calibrated with field measurements. The model is then validated by another set of mutually exclusive field measurements under different geological conditions. The model can simulate the short term (one year) and long term (a few years) with the same level of fidelity.