DOI: 10.18739/a2rf5kg91
title: Alaskan Beaufort Shelf Evolution Model Setup and Output Data Files

description: Data available for download at https://arcticdata.io/data/10.18739/A2H70820F/ Supplementary material for Malito et al., 2022, Evolution of Arctic continental shelves: modelling morphologic feedbacks to climate driven increases in sea states, Journal of Geophysical Research: Oceans The data include model setup files (Delft3D-FLOW) and output results supporting research on the evolution of the Arctic continental shelves. In this study we used the Alaskan Beaufort Shelf as an analog for Arctic shelves undergoing climate-driven changes to sediment transport dynamics. Model trials were conducted using Delft3D-FLOW and processed using Matlab. Arctic continental shelves, including the Alaskan Beaufort Shelf (ABS), are experiencing declines in sea ice coverage and duration which are leading to increasingly energetic sea states and coastal erosion. A Delft3D sediment transport model was developed to test how present-day and projected future waves impact shelf evolution, and how shelf geometry modifies propagation of waves toward the coast. Wave-induced sediment transport and morphologic adjustment were enhanced on a relatively steep ABS shelf section (slope 0.0008) under increased projected waves. Redistribution of sediments from the inner shelf to the middle shelf led to attenuation of projected waves as the shelf evolved, creating a regulatory feedback loop. In contrast, effective wave attenuation across a relatively flat shelf section (slope 0.0003) limited cross-shelf transport and morphologic change. Our findings suggest that morphodynamic feedbacks to the growing Arctic wave climate depend on shelf geometry and can impact future coastal erosion. Experimental setup includes 1000-year morphodynamic evolution simulations conducted of two representative cross-shelf sections (located near Harrison Bay, AK, and Flaxman Island, AK) under two wave climates each ("Present-Day" waves and "RCP8.5" waves). Wave climates were extracted from a publicly available datasets (Casas-Prat et al., 2018). Annual time series were constructed for the Alaskan Beaufort shelf over a hindcast period from 1979-2005 and RCP8.5 projected period between 2081 and 2100 (Casas-Prat et al., 2018). The 1979-2005 wave hindcast is hereafter referred to as present-day waves, and the projected 2081-2100 dataset is referred to as RCP8.5 waves. A representative Beaufort Sea storm was then applied to the four output shelf profiles to evaluate the impact of shelf geometry on wave attenuation. Contents include: 1) Delft3D-FLOW model setup files for 1000-year model simulations a) Harrison Bay, AK i) Present-day waves ii) RCP8.5 waves b) Flaxman Island, AK 2) Delft3D-FLOW model setup files for representative storm trials 3) Processed Matlab structures and metadata for model results (1 and 2) Present-Day and RCP8.5 wave datasets were extracted from the Arctic wave climate projections conducted here: Casas-Prat, M., Wang, X. L., and Swart, N. (2018). CMIP5-based global wave climate projections including the entire Arctic Ocean. Ocean Modelling, 123(April 2017), 66–85. https://doi.org/10.1016/j.ocemod.2017.12.003