Re-gridded and topographically corrected geothermal heat flow data. Supplementary material for Lösing et al. (2025): Community Heat Flow Recommendations: Suitable Basal Boundary Conditions for Greenland and Antarctica in ISMIP7.

These datasets are supplementary material to the publication from Lösing et al. (2025): Community Heat Flow Recommendations: Suitable Basal Boundary Conditions for Greenland and Antarctica in ISMIP7. When using these data, please cite the original datasets and associated publications, as well as Lösing et al. (2025). Input datasets Antarctica Data taken from Lösing & Ebbing (2021a,b); native resolution 55km Data taken from Stål et al., (2020, 2021); native resolution 20 km; The original Aq1 dataset from Stål et al. (2020, 2021), including uncertainty metrics, was cropped at the coastline and grounding line due to the extent of some observables used. To facilitate regridding, we applied a buffered nearest neighbour extrapolation technique to create a processed version of the dataset. We created a spatial buffer extending 4 grid cells (equivalent to 80 km given the 20×20 km resolution) around the valid values in Aq1 using morphological dilation with a circular kernel. We then applied nearest neighbour extrapolation to fill all NaN values across every variable in the dataset, followed by masking to retain only the extrapolated values within the 80 km buffer zone. This approach preserves the original model while adding a controlled "corona" of extrapolated values that extends smoothly into previously undefined regions, reducing edge effects and discontinuities that could occur during regridding procedures. Greenland Data taken from Colgan & Wansing (2021), Colgan et al. (2022); native resolution 55 km Output datasets “GHF_Regridded.zip” - Re-gridded datasets to 500 m resolution for Antarctica and to 500 m and 150 m resolution for Greenland using bilinear interpolation, with respective uncertainties. “GHF_Topographically_Corrected.zip” - Topographically corrected, re-gridded datasets (Antarctica: 500 m resolution; Greenland: 500 m and 150 m resolution) without uncertainties. Geothermal heat flow values are provided in W/m2. The grid resolutions of 500 m for Antarctica and 150 m for Greenland were chosen to correspond with the resolution of the topographic correction datasets as well as with the respective BedMachine datasets (Antarctica v3: Morlighem (2020), Morlighem et al., (2022a); Greenland v5: Morlighem et al. (2017, 2022b)). However, we also include a file for Greenland that has been regridded to 500m and topographically corrected for completeness. For Greenland, datasets are provided with and without data from the North Greenland Ice Core Project (NGRIP; for details see Colgan et al., 2022). “GHF_Original_Data.zip” and “Topographic_Correction.zip” - For quality control we also provide the input datasets with respective uncertainties, and the topographic correction datasets for Greenland and Antarctica (Colgan et al., 2021b) References: Colgan, William; Wansing, Agnes, (2021): Greenland Geothermal Heat Flow Database and Map. GEUS Dataverse, V2. https://doi.org/10.22008/FK2/F9P03L Colgan, W., Wansing, A., Mankoff, K., Lösing, M., Hopper, J., Louden, K., Ebbing, J., Christiansen, F. G., Ingeman-Nielsen, T., Liljedahl, L. C., MacGregor, J. A., Hjartarson, Á., Bernstein, S., Karlsson, N. B., Fuchs, S., Hartikainen, J., Liakka, J., Fausto, R. S., Dahl-Jensen, D., Bjørk, A., Naslund, J.-O., Mørk, F., Martos, Y., Balling, N., Funck, T., Kjeldsen, K. K., Petersen, D., Gregersen, U., Dam, G., Nielsen, T., Khan, S. A. & Løkkegaard, A. (2022): Greenland Geothermal Heat Flow Database and Map (Version 1). Earth Syst. Sci. Data14, 2209–2238. https://doi.org/10.5194/essd-14-2209-2022 Colgan, William, Joseph A. MacGregor, Kenneth D. Mankoff, Ryan Haagenson, Harihar Rajaram, Yasmina M. Martos, Mathieu Morlighem, Mark A. Fahnestock, and Kristian K. Kjeldsen. (2021b): Topographic correction of geothermal heat flux in Greenland and Antarctica." Journal of Geophysical Research: Earth Surface 126, no. 2. e2020JF005598. doi: 10.1029/2020JF005598 Lösing, Mareen; Ebbing, Jörg (2021a): Predicted Antarctic Heat Flow and Uncertainties using Machine Learning [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.930237. https://doi.org/10.1594/PANGAEA.930237 Lösing, M., & Ebbing, J. (2021b): Predicting geothermal heat flow in Antarctica with a machine learning approach. Journal of Geophysical Research: Solid Earth, 126(6), e2020JB021499. https://doi.org/10.1029/2020JB021499 Morlighem, M., Rignot, E., Binder, T., Blankenship, D. D., Drews, R., Eagles, G., Eisen, O., Ferraccioli, F., Forsberg, R., Fretwell, P., Goel, V., Greenbaum, J. S., Gudmundsson, H., Guo, J., Helm, V., Hofstede, C., Howat, I., Humbert, A., Jokat, W., Karlsson, N. B., Lee, W., Matsuoka, K., Millan, R., Mouginot, J., Paden, J., Pattyn, F., Roberts, J. L., Rosier, S., Ruppel, A., Seroussi, H., Smith, E. C., Steinhage, D., Sun, B., van den Broeke, M. R., van Ommen, T., van Wessem, M. & Young, D. A.. (2020): Deep glacial troughs and stabilizing ridges unveiled beneath the margins of the Antarctic ice sheet. Nature Geoscience. 13. DOI: 10.1038/s41561-019-0510-8. Morlighem, M. (2022a): MEaSUREs BedMachine Antarctica. (NSIDC-0756, Version 3). [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/FPSU0V1MWUB6 Morlighem, M., Williams, C., Rignot, E., An, L., Arndt, J. E., Bamber, J. L., Catania, G., Chauché, N., Dowdeswell, J. A., Dorschel, B., Fenty, I., Hogan, K., Howat, I., Hubbard, A., Jakobsson, M., Jordan, T. M., Kjeldsen, K. K., Millan, R., Mayer, L., Mouginot, J., Noël, B., O'Cofaigh, C., Palmer, S. J., Rysgaard, S., Seroussi, H., Siegert, M. J., Slabon, P., Straneo, F., van den Broeke, M. R., Weinrebe, W., Wood, M. & Zinglersen, K.. (2017): BedMachine v3: Complete bed topography and ocean bathymetry mapping of Greenland from multi-beam echo sounding combined with mass conservation. Geophysical Research Letters. 44. DOI: 10.1002/2017GL074954. Morlighem, M. et al. (2022b): IceBridge BedMachine Greenland. (IDBMG4, Version 5). [Data Set]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. https://doi.org/10.5067/GMEVBWFLWA7X. Stål, T., Reading, A. M., Halpin, J. A., Whittaker, J. M. (2020): Antarctic geothermal heat flow model: Aq1 [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.924857. Stål, T., Reading, A. M., Halpin, J. A., & Whittaker, J. M. (2021): Antarctic geothermal heat flow model: Aq1. Geochemistry, Geophysics, Geosystems, 22(2), e2020GC009428. https://doi.org/10.1029/2020GC009428