Global datasets: Difference between revisions

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== ETOPO ==
== ETOPO ==
The ETOPO datasets provide global topography and bathymetry at 1', 2', and 5' per-cell resolutions.


=== ETOPO1 ===
=== ETOPO1 ===

Revision as of 12:32, 13 October 2008

Blue Marble imagery

ETOPO

The ETOPO datasets provide global topography and bathymetry at 1', 2', and 5' per-cell resolutions.

ETOPO1

The cell registered version can be loaded directly into a lat/lon region. GRASS raster data is cell registered (see the GRASS raster semantics page)


The grid registered version must be loaded into a simple XY location using the parameters found in the .hdr file, and needs to have the 90deg N,S rows cropped away:

# create a new simple XY location and mapset

# Import grid registered binary float
r.in.bin -f in=etopo1_bed_g.flt out=etopo1_bed_g \
   n=90.008333333335 s=-90.008333333335 e=180.00833333334 \
   w=-180.00833333334 rows=10801 cols=21601 anull=-9999
r.colors out=etopo1_bed_g color=etopo2

# reduce region by 1 cell
g.region rast=etopo1_bed_g
eval `g.region -g`
g.region n=n-$nsres s=s+$nsres e=e-$ewres -p

# save smaller raster and remove original
r.mapcalc "etopo1_bed_g.crop = etopo1_bed_g"
g.remove etopo1_bed_g

# change the location to lat/lon by restarting GRASS
#  in the PERMANENT mapset and running g.setproj
#  or move the entire mapset into a lat/lon location
#  and manually edit the $MAPSET/cellhd/ files (dirty!)

ETOPO2

ETOPO2v2 data download

GEBCO

  • The General Bathymetric Chart of the Oceans
http://www.gebco.net/data_and_products/gridded_bathymetry_data/

Miscellaneous

  • The r.in.gdal modules may be used to import data of many formats, including GMT netCDF
  • The r.in.bin module may be used to import raw binary files

LANDSAT

MODIS

Pathfinder AVHRR SST

merge that info here?

QuickBird

SeaWiFS

merge that info here?

Smith and Sandwell

SRTM


VMap0

1:1 million vector data. Formerly known as Digital Chart of the World