topoWorld: Global Topographic Dataset at Half-degree Resolution
Description
Global topographic dataset at half-degree resolution, created by decimating the
ETOPO5 dataset. Its longitude ranges from -179.5 to 180, and its latitude
ranges from -89.5 to 90. Height is measured in metres above nominal sea level.
The coarse resolution can be a problem in plotting depth contours along with
coastlines in regions of steep topography. For example, near the southeast
corner of Newfoundland, a 200m contour will overlap a coastline drawn with
coastlineWorldFine. The solution in such cases is to
download a higher-resolution topography file and create a topo object
with read.topo or as.topo.
Usage
data(topoWorld)
Arguments
Source
The binary ETOPO5 dataset was downloaded in late 2009 from the NOAA website,
http://www.ngdc.noaa.gov/mgg/global/relief/ETOPO5/TOPO/ETOPO5 (link last checked 2016-06-12),
decoded, decimated from 1/12th degree resolution to 1/2 degree resolution, and
passed through matrixShiftLongitude so that longitude is
between -180 and 180 degrees.