Geoscience Reference
In-Depth Information
Fig. 7.1
Shoreline display from the GSHHS data set. h e map shows an area between latitudes
0° and 15° north, and longitudes 40° and 50° east. h is simple map is made using the function
plot
, with equal axis aspect ratios (data from Wessel and Smith 1996).
map properties such as the map projection, the map limits, and the axis
labels.
7.3 The 1-Minute Gridded Global Relief Data ETOPO1
ETOPO1 is a global data base of topographic and bathymetric data on a
regular 1 arc-minute grid (about 2 km) (Amante and Eakins 2009). Older
ETOPO2v2 and ETOPO5 global relief grids have been superseded but are
still available. ETOPO1 is a compilation of data from a variety of sources. It
can be downloaded from the US National Geophysical Data Center (NGDC)
web page
http://www.ngdc.noaa.gov/mgg/global/
As an example we use the data from the i le
grid01-258.asc
that has the
following content:
