Marthews, T.R.; Dadson, S.J.; Lehner, B.; Abele, S.; Gedney, N.

High-resolution global topographic index values

The topographic index is a hydrological quantity describing the propensity of the soil at landscape points to become saturated with water as a result of topographic position (i.e. not accounting for other factors such as climate that also affect soil moisture but are accounted for separately). Modern land surface models require a characterisation of the land surface hydrological regime and this parameter allows the use of the TOPMODEL hydrological model to achieve this .This Geographic Information System layer is intended for use as topographic ancillary files for the TOPMODEL routing model option within the Joint UK Land Environment Simulator (JULES) land surface model. The topographic index variable here is directly comparable to the compound topographic index available from United States Geological Survey's Hydro1K at 30 sec resolution.

Publication date: 2014-11-30

Get the data

This dataset is made available under the terms of the Open Government Licence

Format of the dataset : NetCDF

You must cite: Marthews, T.R.; Dadson, S.J.; Lehner, B.; Abele, S.; Gedney, N. (2014). High-resolution global topographic index values. NERC Environmental Information Data Centre.


© Centre for Ecology & Hydrology (Natural Environment Research Council)


Study area
Temporal extent
2014-01-01    to    …

Provenance & quality

The GA2 algorithm has been used to calculate these topographic index values, using base data layers provided by the HydroSHEDS suite of GIS layers. All files were generated using FORTRAN 90 at 15 arc-sec resolution (cells circa 450 m x 450 m at the Equator).

Correspondence/contact details

Marthews, T.R.
Centre for Ecology & Hydrology


Marthews, T.R.
University of Oxford
Dadson, S.J.
University of Oxford
Lehner, B.
McGill University
Abele, S.
University of Oxford
Gedney, N.
Hadley Centre for Climate Prediction and Research

Other contacts

Environmental Information Data Centre
NERC Environmental Information Data Centre


Spatial representation type
Spatial reference system
WGS 84


Topic categories
hydrological regimes,  hydrology,  Hydrology inundation,  soil moisture,  spatial data,  Topography