pDEMtools

Conveniently search, download, and preprocess ArcticDEM and REMA products.

pDEMtool provides a convenient set of functions to explore, download, and preprocess high-resolution DEMs of the polar regions from the ArcticDEM (Porter et al. 2022; 2023) and Reference Elevation Model of Antarctica (REMA; Howat et al. 2022a, b) products, courtesy of the Polar Geospatial Center (PGC).

The first aim of pDEMtools is to enable access to ArcticDEM and REMA mosaics and multitemporal strips using the search() function and load module:

• search(): This function aims to replicate the kind of convenient catalogue searching available when querying a dynamic STAC catalogue (e.g. pystac_client), allowing users to easily find relevant ArcticDEM and REMA strips for their areas of interest.

• load: This module provides simple one-line functions to preview and download strips and mosaics from the relevant AWS bucket to an xarray Dataset.

The second aim is to provide (pre)processing functions specific to the sort of uses that ArcticDEM and REMA users might want (e.g. a focus on ice sheet and cryosphere work), as well as the particular strengths of ArcticDEM and REMA datasets (high-resolution and multitemporal). Tools include:

• Terrain attribute derivation (hillshade, slope, aspect, various curvatures) using a 5x5 polynomial fit suited for high-resolution data.

• Quick geoid correction using BedMachine source data.

• Simple coregistration for quick elevation change analysis.

• Identifying/masking sea level and icebergs.

Rather than introducing custom classes, pDEMtools will always try and return DEM data as an xarray DataArray with geospatial metadata via the rioxarray extension. The aim is to allow the user to quickly move beyond pDEMtools into their own analysis in whatever format they desire, be that xarray, numpy or dask datasets, DEM-specific Python packages such as xdem for advanced coregistration or richdem for flow analysis, or exporting to geospatial file formats for analysis beyond Python.

Contact me: Tom Chudley, thomas.r.chudley@durham.ac.uk

Getting Started:

• Install
  • Cloning from GitHub
  • Dependencies
  • A note on installing dependencies
• Supplementary datasets
  • ArcticDEM/REMA strip index
  • BedMachine v5
• Cite

Examples:

• Download mosaic and calculate terrain parameters
  • Load mosiac
  • Postprocessing
• Strip search and coregistraion
  • Searching for strips
  • Downloading the strips
  • Coregistration and DEM differencing
• Iceberg detection
  • Finding a strip
  • Geoid correction
  • Sea level filtering
• Batch processing

API reference:

• pdemtools.search function
  • search()
• pdemtools.load module
  • from_fpath()
  • from_id()
  • from_search()
  • mosaic()
  • preview()
• pdemtools.data module
  • bedrock_mask_from_bedmachine()
  • bedrock_mask_from_vector()
  • geoid_from_bedmachine()
  • geoid_from_raster()
• xarray .pdt accessor
  • DemAccessor
    • DemAccessor.coregister()
    • DemAccessor.geoid_correct()
    • DemAccessor.get_sea_level()
    • DemAccessor.mask_icebergs()
    • DemAccessor.mask_ocean()
    • DemAccessor.terrain()

Appendix:

• Community guide
  • Report issues or problems
  • Contribute to pDEMtools
• Version updates
• Refererences
• Acknowledgements

Indices and tables

• Index

• Module Index

• Search Page