These data include shapefiles of streamlined subglacial bedforms, elongate bedforms created at the glacier-bed interface by erosional and depositional processes, characterized by polygons across nine deglaciated geographic locations in the Northern Hemisphere. Assessed deglaciated sites include the Puget Lowland, Washington, United States; northwestern Pennsylvania, United States; Chautauqua, New York, United States; M'Clintock Channel, Canada; Prince of Wales Island, Canada; Nunavut, Canada; Bárðardalur, Iceland; northern Norway; and northern Sweden. These data are based on digital elevation models (DEMs) published by Clallam County, 2005, Porter et al., 2018, and the United States Geologic Survey, 1999, 2000. Streamlined subglacial bedform polygons were identified semi-automatically utilizing Topographic Position Index (TPI) methodology, used to calculate elevation and slope variations across any Digital Elevation Model (Weiss, 2001; Tagil & Jenness, 2008), and manual assessment of the landscape. The TPI ArcPython code and ArcGIS model builder tool developed and utilized in this project are also included in the attached data. Shapefile attribute tables and excel file include streamlined subglacial bedform morphologies for all 11,628 bedforms including area, width, length, orientation, elevation and slope ranges, and elongation. The morphological characteristics of these streamlined subglacial bedforms provide information on ice-streaming characteristics across variable bed lithology and topographic settings.

Each polygon shapefile contains attribute table information including: FID, Shape (“polygon ZM”) indicates a manually drawn bedform, “polygon” is an automatically identified bedform feature), Shape_Area (square meters), ORIG_FID, MBG_Width (meters), MBG_Length (meters), MBG_APodX1, MBG_APodY1, MBG_APodX2, MBG_ApodY2, MBG_Orient (degrees), Z_Min (meters), Z_Max (meters), Z_Mean (meters), Min_Slope (degrees), Max_Slope (degrees), Avg_Slope (degrees), deltaZ (meters), and ElongRatio (meter/meter).Included shapefiles in separate .zip folders:PugetLowland_WA_US.shpNorthwesternPA_US.shpBardardalur_Iceland.shpChautauqua_NY_US.shpMClintockChannel_Canada.shpNorthernNorway.shpPrinceofWalesIsland_Canada.shpNunavut_Canada.shpNorthernSweden.shp“McKenzie_Bedform_RawData.xlsx” :Includes all raw data output from bedform shapefile attribute tables. Each site data has a separate tab in the excel file. Units for columns are the same as the above shapefiles.“TPI Tool and Code.zip”:TPI_SemiAutomatedTool toolbox includes the ArcGIS model builder tool “TPI_SemiAutomatedID”. This model includes TPI ArcPython code as a step and then implement spatial analyst tools to create the output polygon file of all positive relief features of varying scales (dependent on neighborhood sizes). The ArcPython code “TPI_code” in also included.