Calculated seafloor ruggedness index (TRI) of the Baltic Sea

Martin Jakobsson

Terrain ruggedness index (TRI) of the Baltic Sea floor calculated using the European Marine Observation and Data Network (EMODnet) 2019 bathymetric grid as a base. The TRI values provide a measure of the variation in the terrain, i.e. the ruggedness or sometimes referred to as roughness. High/low TRI-values means large/small topographic variations. It is commonly used in studies of land or ocean morphology.

Citation

Martin Jakobsson (2019) Calculated seafloor ruggedness index (TRI) of the Baltic Sea. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/jakobsson-2019-ruggedness-1

References

Jakobsson, M., Stranne, C., O'Regan, M., Greenwood, S. L., Gustafsson, B., Humborg, C., Weidner, E. (2019): Bathymetric Properties of the Baltic Sea, Ocean Science, 2019, https://doi.org/10.5194/os-2019-18

Data description

The Terrain Ruggedness Index (TRI) dataset is provided in one zipped geotiff (.tif) file. TRI was calculated using the EMODnet gridded bathymetry as a base. Calculation was done on a reprojected version of the EMODnet grid: 100x100 m grid cell-size, Lambert Equal Area with the parameters specified as in the European Terrestrial Reference System (ETRS) 1989 (ETRS89-LAEA). The TRI algorithm calculates the average of the sum of the absolute differences between the neighboring cells and the centre cell. A radius of 10 cells was used, implying a block of 2100 x 2100 m over which a TRI value is calculated.

Comments

TRI of the Baltic Sea floor was computed using the algorithm available with the Open Source System for Automated Geoscientific Analyses (SAGA). This work was done for the study of the Bathymetric Properties of the Baltic Sea published in Ocean Science (Jakobsson et al. 2019).