Description:
These Reference grids have been created for the NaturaConnect project and are based on an intersection of the European Coastline delineation and the GADM database.
Thee reference grids have been created in a way so that they are fully consistent with the EEA reference grid (https://www.eea.europa.eu/data-and-maps/data/eea-reference-grids-2), meaning that for example two 5km gridded cells fully match a 10km grid cell in width.

Filestructure:
ReferenceGrid_Europe_{format}_{grain}

• format is either "frac" for fractional data (which has been multiplied with 10000 to save in integer format) or binary (0,1).
• grain is provided as layers in 100m, 1000m, 5000m, 10000m, 50000m spatial resolution. Alternative aggregations can be provided on request.

File format:
The layers are gridded geoTiff files and can be loaded in any conventional Graphical Information System (GIS) or specific analytical programming languages (e.g. R or python). In addition external pyramids (.tfw) have been precreated to enable faster rendering.

Geographic projection:
We use the Lamberts-Equal-Area Projection by default for all layers in NaturaConnect. This is an equal-area (but distorted shape) projection and commonly used by European institution with a focus on the European continent. For global layers the equal-area World Mollweide projection is used.

Sourcecode:
The code to reproduce the layers has been made available in the "code" file.

The 2009 Human Footprint, 2018 Release provides a global map of the cumulative human pressure on the environment in 2009, at a spatial resolution of ~1 km. The human pressure is measured using eight variables including built-up environments, population density, electric power infrastructure, crop lands, pasture lands, roads, railways, and navigable waterways. The data set is produced by Venter et.al., and is available in the Mollweide projection.