Edge-bundled spatial layer to visualize mobility flows in Europe on NUTS 2 level

Description of edge-bundled spatial layer

This repository contains a GeoPackage of edge-bundled line geometries between the centroids of all NUTS 2 regions in continental Europe. The centroids of the NUTS 2 regions are derived from the 2021 version of the regions. The spatial layer contains just the edge-bundled lines, and no values for the flows. The coordinate reference system used is the ETRS89-extended / LAEA Europe (EPSG:3035) commonly used by The European Union.

This data is made to support the visualization of complex origin-destination matrix mobility data on the NUTS 2 level in Europe. Straight line geometries between origin and destination points can lose their legibility when the number of flows gets high. 

Usage

To use the spatial layer, combine the provided GeoPackage with your origin-destination matrix data, such as migration, student exchange, or some other flow data. The edge-bundled flows has a directionality-preserving column for joining the flows (OD_ID).  This can be done in QGIS/ArcGIS with a table join or in R/Python with a data frame merge. 

Data structure

Column
Description
Datatype

fid
Unique identifier for a row in the data
Integer (64 bit)

orig_nuts
The NUTS 2 code of the origin.
String

dest_nuts
The NUTS 2 code of the destination.
String

OD_ID
Unique identifier for the mobility using the NUTS 2 codes for origin and destination. E.g., FI1B_DK03
String

Production code

The spatial layer was produced by the Edge-bundling tool for regional mobility flow data, which is a fork of a similar tool by Ondrej Peterka (2024), which is based on the work of Wallinger et al., (2022).

References

Peterka, O. (2024). Xpeterk1/edge-path-bundling [Python, C++]. https://github.com/xpeterk1/edge-path-bundling (Original work published 2023)

Wallinger, M., Archambault, D., Auber, D., Nöllenburg, M., & Peltonen, J. (2022). Edge-Path Bundling: A Less Ambiguous Edge Bundling Approach. IEEE Transactions on Visualization and Computer Graphics, 28(1), 313–323. https://doi.org/10.1109/TVCG.2021.3114795