DOI: 10.5281/zenodo.14920387
title: Multiscale Land Surface Parameters of GEDTM30: Topographic Wetness Index

description: Topographic Wetness Index


This data is part of the Global Ensemble Digital Terrain Model (GEDTM30) dataset. Check the related identifiers section below to access other parts of the dataset.


Disclaimer


This is the first release of the Multiscale Land Surface Parameters (LSPs) of Global Ensemble Digital Terrain Model (GEDTM30). Use for testing purposes only. This work was funded by the European Union. However, the views and opinions expressed are solely those of the author(s) and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the granting authority can be held responsible for them. The data is provided "as is." The Open-Earth-Monitor project consortium, along with its suppliers and licensors, hereby disclaims all warranties of any kind, express or implied, including, without limitation, warranties of merchantability, fitness for a particular purpose, and non-infringement. Neither the Open-Earth-Monitor project consortium nor its suppliers and licensors make any warranty that the website will be error-free or that access to it will be continuous or uninterrupted. You understand that you download or otherwise obtain content or services from the website at your own discretion and risk.



Description


LSPs are derivative products of the GEDTM30 that represent measures of local topographic position, curvature, hydrology, light, and shadow. A pyramid representation is implemented to generate multiscale resolutions of 30m, 60m, 120m, 240m, 480m, and 960m for each LSP. The parametrization is powered by Whitebox Workflows in Python. To see the documentation, please visit our GEDTM30 GitHub (https://github.com/openlandmap/GEDTM30).



Dataset Contents


This dataset includes:


    
Global Topographic Wetness Index 120m
    
Global Topographic Wetness Index 240m
    
Global Topographic Wetness Index 480m
    
Global Topographic Wetness Index 960m



Due to Zenodo's storage limitations, the high resolution LSP data are provided via external links:


    
Global Topographic Wetness Index 30m
    
Global Topographic Wetness Index 60m




Related Identifiers



    
Digital Terrain Model:
        GEDTM30
    
    
Landform:
        Slope in Degree, Geomorphons
    
    
Light and Shadow:
        Positive Openness, Negative Openness,
        Hillshade
    
    
Curvature:
        Minimal Curvature, Maximal Curvature,
        Profile Curvature, Tangential Curvature, 
        Ring Curvature, Shape Index
    
    
Local Topographic Position:
        Difference from Mean Elevation, Spherical Standard Deviation of the Normals
    
    
Hydrology:
        Specific Catchment Area, LS Factor, Topographic Wetness Index
    




Data Details



	
Time period: static.
	
Type of data: properties derived from Digital Terrain Model
	
How the data was collected or derived: The data was derived using Whitbox Workflows.
	
Methods used: LSP algorithms.
	
Limitations or exclusions in the data: The dataset does not include data Antarctica. 
	
Coordinate reference system: EPSG:4326
	
Bounding box (Xmin, Ymin, Xmax, Ymax): (-180, -65, 180, 85)
	
Spatial resolution: 120m, 240m, 480m, 960m
	
Image size: 360,000P x 178,219L; 180,000P x 89,110L; 45,000L x 22,282L  
	
File format: Cloud Optimized Geotiff (COG) format.
    
Additional information:
    


  
    Layer
    Scale
    Data Type
    No Data
  
  
    Difference from Mean Elevation
    100
    Int16
    32,767
  
  
    Geomorphons
    1
    Byte
    255
  
  
    Hillshade
    1
    UInt16
    65,535
  
  
    LS Factor
    1,000
    UInt16
    65,535
  
  
    Maximal Curvature
    1,000
    Int16
    32,767
  
  
    Minimal Curvature
    1,000
    Int16
    32,767
  
  
    Negative Openness
    100
    UInt16
    65,535
  
  
    Positive Openness
    100
    UInt16
    65,535
  
  
    Profile Curvature
    1,000
    Int16
    32,767
  
  
    Ring Curvature
    10,000
    Int16
    32,767
  
  
    Shape Index
    1,000
    Int16
    32,767
  
  
    Slope in Degree
    100
    UInt16
    65,535
  
  
    Specific Catchment Area
    1,000
    UInt16
    65,535
  
  
    Spherical Standard Deviation of the Normals
    100
    Int16
    32,767
  
  
    Tangential Curvature
    1,000
    Int16
    32,767
  
  
    Topographic Wetness Index
    100
    Int16
    32,767
  




Support


If you discover a bug, artifact, or inconsistency, or if you have a question please raise a GitHub issue here


Naming convention


To ensure consistency and ease of use across and within the projects, we follow the standard Ai4SoilHealth and Open-Earth-Monitor file-naming convention. The convention works with 10 fields that describe important properties of the data. In this way users can search files, prepare data analysis etc, without needing to open files.


For example, for twi_edtm_m_120m_s_20000101_20221231_go_epsg.4326_v20241230.tif,  the fields are:



	
generic variable name: twi = topographic wetness index
	
variable procedure combination: edtm = derivative direct from global ensemble digital terrain model
	
Position in the probability distribution/variable type: m = measurement
	
Spatial support: 120m
	
Depth reference: s = surface
	
Time reference begin time: 20000101 = 2000-01-01
	
Time reference end time: 20211231 = 2021-12-31
	
Bounding box: go = global
	
EPSG code: EPSG:4326
	
Version code: v20241230 = version from 2024-12-30