This package includes files and MATLAB scripts to calculate morphologic metrics and stream power law erosion quantities for the submitted paper citable as:

Higa, Justin T., Rowland, Scott K. (in review) Volcanic and climatic controls on million-year valley incision, West Maui Volcano, Hawaiʻi.

This package is registered on Zenodo as:

Higa, Justin T., Rowland, Scott K. (2025). WestMauiMyrErosion (v0.0.0-alpha). Zenodo. https://doi.org/10.5281/zenodo.15571948

HigaandRowlandValleyTopo.m and HigaandRowlandDivideMigration.m require the TopoToolbox 2 (Scherler & Schwanghart, 2020; Schwanghart & Scherler, 2014) and DivideTools (Forte & Whipple, 2018) packages. For Topotoolbox 2, the refmat2XY.m function must be taken out of the private folder in the @GRIDobj folder and placed in a findable location (e.g., directly in the @GRIDobj folder). RGB triple of color name, version 2 (https://www.mathworks.com/matlabcentral/fileexchange/24497-rgb-triple-of-color-name-version-2; last accessed 15 May 2025) is also required for plotting.

Several MATLAB scripts are provided: 1) HigaandRowlandValleyTopo.m and HigaandRowlandDivideMigration.m are the main scripts. 2) meanbin.m was used for simple plotting of binned data. 3) AcrossDivideJH.m is modified from AcrossDivideJH.m in DivideTools to include the 'ultralax' option for the 'divide_buffer' optional input.

Several rasters are provided: 1) The distance from Bouguer gravity high is from Strange et al. (1965) as Strangegravcalddist.asc. 2) The reconstructed surface is Wmauithinplatespline.asc, zipped as Wmauithinplatespline.zip. Points used to interpolate this surface is Wmauithinplatespline_points.csv.

Several shapefiles are provided: 1) The West Maui Volcano caldera outline is adapted from Sherrod et al. (2021a,b) as Wailukucalderafull.shp. 2) West Maui valleys analyzed are WMVValleys.shp, valleys named in the paper are WMVValleys_main.shp.

Several tables are provided: 1) Mauivalleyaspect.csv holds the valley ID number, valley widths [m], and corresponding valley lengths [m]. There is one row for each width measured, where the ID and valley length is constant for each valley. 2) Wmauithinplatesplinepoints.csv holds the Easting, Northing, elevation, and point type for points used in the reconstructed surface thin-plate spline.

Several rasters must be downloaded from other sources: 1) The digital elevation model is the USGS EDNA 10-m resolution digital elevation model of Hawaiʻi (downloadable from https://earthexplorer.usgs.gov/; last accessed 15 May 2025). See http://edna.usgs.gov for more information. 2) The rainfall map and standard deviation is from the Hawaiʻi Rainfall Atlas (Giambelluca et al., 2013; downloadable from https://www.hawaii.edu/climate-data-portal/rainfall-atlas/; last accessed 15 May 2025). These are the "Rainfall Grids" and "Uncertainty" maps in ASCII Grid Format, millimeters.

*The MATLAB scripts have a line to clip all rasters, including these that must be downloaded, to the same extent as that in the paper. The exact extent of self-downloaded rasters does not have to match that of the rasters provided in order to work. However, the extent of the self-downloaded rasters, particularly the EDNA elevation, must not be smaller than the extent of the provided ones. Also, if self-downloaded rasters are too large, this may affect run time.

Citations:

Forte, A. M., & Whipple, K. X. (2018). Criteria and tools for determining drainage divide stability. Earth and Planetary Science Letters, 493, 102–117. https://doi.org/10.1016/j.epsl.2018.04.026

Giambelluca, T. W., Chen, Q., Frazier, A. G., Price, J. P., Chen, Y.-L., Chu, P.-S., et al. (2013). Online Rainfall Atlas of Hawai‘i. Bulletin of the American Meteorological Society, 94(3), 313–316. https://doi.org/10.1175/BAMS-D-11-00228.1

Jonasson, K. (2025). RGB triple of color name, version 2 (https://www.mathworks.com/matlabcentral/fileexchange/24497-rgb-triple-of-color-name-version-2), MATLAB Central File Exchange. Retrieved May 15, 2025.

Scherler, D., & Schwanghart, W. (2020). Drainage divide networks – Part 1: Identification and ordering in digital elevation models. Earth Surface Dynamics, 8(2), 245–259. https://doi.org/10.5194/esurf-8-245-2020

Schwanghart, W., & Scherler, D. (2014). Short Communication: TopoToolbox 2 – MATLAB-based software for topographic analysis and modeling in Earth surface sciences. Earth Surface Dynamics, 2(1), 1–7. https://doi.org/10.5194/esurf-2-1-2014

Sherrod, D. R., Robinson, J., Sinton, J., Watkins, S., & Brunt, K. (2021a). Geologic map database to accompany geologic map of the State of Hawai ‘i: US Geological Survey data release. https://doi.org/10.5066/P9YWXT41

Sherrod, D. R., Sinton, J. M., Watkins, S. E., & Brunt, K. M. (2021b). Geologic Map of the State of Hawaiʻi (No. 3143). U.S. Geological Survey. https://doi.org/10.3133/sim3143

Strange, W. E., Woollard, G. P., & Rose, J. C. (1965). An Analysis of the Gravity Field Over the Hawaiian Islands in Terms of Crustal Structure. Pacific Science, 19(3), 381–389.