DOI: 10.5281/zenodo.18632349
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 release v1.2 of the Multiscale Land Surface Parameters (LSPs) / Terrain derivative  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://codeberg.org/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

Light and Shadow:Hillshade

Curvature:Minimal Curvature, Maximal Curvature, Profile Curvature, Tangential Curvature

Local Topographic Position:Difference from Mean Elevation, Spherical Standard Deviation of the Normals

Hydrology:D8, 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, -64, 180, 89)

Spatial resolution: 120m, 240m, 480m, 960m

Image size: 324,000P x 138,026L; 162,000P x 178,219L; 69,013P x 89,110L; 34,507L x 17,254L

File format: Cloud Optimized Geotiff (COG) format.

Additional information:


 




Layer
Scale
Data Type
No Data


Difference from Mean Elevation
100
Int16
32,767


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


Profile Curvature
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


D8 flow direction
1
Uint8
255


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 Codeberg 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_gedtm_m_120m_s_20060101_20151231_go_epsg.4326_v1.2.0.tif, the fields are:



generic variable name: twi = topographic wetness index

variable procedure combination: gedtm = 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: 20060101 = 2006-01-01

Time reference end time: 20151231 = 2015-12-31

Bounding box: go = global

EPSG code: EPSG:4326

Version code: v1.2.0 = version from v1 (major), .2 (minor), .0 (bug fixed)