“Hydrological Contaminant Mobilisation from Thawing Permafrost in Alaska” This repository contains the datasets, processing- and figure-generation scripts used to assess contaminant mobilisation risk at contaminated sites in Alaska under changing permafrost conditions and future climate scenarios (SSP126 and SSP585). The workflow combines: contaminated site information contaminant toxicity and solubility properties permafrost thaw simulations derived from CryoGrid DEM-based flow path analysis hydrological transport proxies ecoregional analysis Included materials comprise: Scripts Flow path analysis for estimating downslope transport distance and elevation differences between contaminated sites and surface water bodies. Dataframe creation scripts for merging contaminant, permafrost, toxicity, solubility, and spatial datasets. Simulation post-processing scripts for generating mean mineral content and decadal CryoGrid outputs. Figure generation scripts used to reproduce manuscript figures. Data The repository contains processed geospatial datasets (.gpkg, .shp) and intermediate analysis products used in the manuscript. Some raw source datasets originate from third-party providers (e.g., HydroLAKES, GRWL, ArcticDEM, Natural Earth, OpenStreetMap) included in the dataset for reproduciblity Reproducibility All scripts use relative file paths and can be executed sequentially following the workflow described in the accompanying README file. Software environment:Python 3.11.15 using packages including GeoPandas, Pandas, NumPy, Rasterio, GDAL, Matplotlib, SciPy, Seaborn, and Shapely. Availability of external datasets: The CryoGridLite model version used in this study is available on GitLab: https://gitlab.awi.de/cryogrid/cryogridlite/-/tree/ContamAlaska. The ERA5 reanalysis data can be downloaded from C3s. (2018). ERA5 hourly data on single levels from 1940 to present [Dataset]. In European Centre for Medium-Range Weather Forecasts. https://doi.org/10.24381/cds.adbb2d47 MPI-ESM1.2-HR climate data can be accessed via https://esgf-data.dkrz.de/search/cmip6-dkrz/. The mosaic tiles of the 32m spatial resolution ArcticDEM are available via https://data.pgc.umn.edu/elev/dem/setsm/ArcticDEM/mosaic/v3.0/32m/ From: Porter, Claire; Morin, Paul; Howat, Ian; Noh, Myoung-Jon; Bates, Brian; Peterman, Kenneth; Keesey, Scott; Schlenk, Matthew; Gardiner, Judith; Tomko, Karen; Willis, Michael; Kelleher, Cole; Cloutier, Michael; Husby, Eric; Foga, Steven; Nakamura, Hitomi; Platson, Melisa; Wethington, Michael, Jr.; Williamson, Cathleen; Bauer, Gregory; Enos, Jeremy; Arnold, Galen; Kramer, William; Becker, Peter; Doshi, Abhijit; D'Souza, Cristelle; Cummens, Pat; Laurier, Fabien; Bojesen, Mikkel, 2018, "ArcticDEM, Version 3", https://doi.org/10.7910/DVN/OHHUKH, Harvard Dataverse, V1 The SIRIUS database is available on Zenodo via: Kaiser, S., Boike, J., Grosse, G., & Langer, M. (2023). SIRIUS - Synthesized inventory of CRitical infrastructure and HUman-Impacted areas in permafrost regions of AlaSka [Dataset]. In Zenodo (CERN European Organization for Nuclear Research). https://doi.org/10.5281/zenodo.8311242 The HydroLAKES dataset can be accessed via https://www.hydrosheds.org/products/hydrolakes#downloads. from: Messager, M.L., Lehner, B., Grill, G., Nedeva, I., Schmitt, O. (2016). Estimating the volume and age of water stored in global lakes using a geo-statistical approach. Nature Communications, 7: 13603. https://doi.org/10.1038/ncomms13603 The Global River Widths from Landsat (GRWL) database is available for download on zenodo: https://zenodo.org/record/1297434#.YvZy8exBzds. from: Allen and Pavelsky (2018) Global Extent of Rivers and Streams. Science. https://doi.org/10.1126/science.aat0636 OpenStreetMap water polygons for oceans and seas are accessable via: https://osmdata.openstreetmap.de/data/water-polygons.html. The ALT validation data is downloadable from https://www2.gwu.edu/~calm/data/north.html. The borehole temperature data can be accessed via the Permafrost Laboratory website: https://permafrost.gi.alaska.edu/ Administrative boundaries, coastlines, and basemap layers were obtained from Natural Earth via: Natural Earth. (n.d.). Natural Earth: free vector and raster map data. Retrieved February 15, 2026, from https://www.naturalearthdata.com/about Level 2 Ecoregion vector data from: Commission for Environmental Cooperation. (2021). North American Environmental Atlas – Terrestrial ecoregions: Level II. U.S. Environmental Protection Agency. https://www.epa.gov/eco-research/ecoregions-north-america