pygmt.datasets.load_earth_vertical_gravity_gradient
- pygmt.datasets.load_earth_vertical_gravity_gradient(resolution='01d', region=None, registration=None)[source]
Load the IGPP Global Earth Vertical Gravity Gradient in various resolutions.
The grids are downloaded to a user data directory (usually
~/.gmt/server/earth/earth_vgg/
) the first time you invoke this function. Afterwards, it will load the grid from the data directory. So you’ll need an internet connection the first time around.These grids can also be accessed by passing in the file name @earth_vgg_res[_reg] to any grid plotting/processing function. res is the grid resolution (see below), and reg is grid registration type (p for pixel registration or g for gridline registration).
Refer to https://www.generic-mapping-tools.org/remote-datasets/earth-vgg.html for more details.
- Parameters
resolution (str) – The grid resolution. The suffix
d
andm
stand for arc-degrees and arc-minutes. It can be"01d"
,"30m"
,"20m"
,"15m"
,"10m"
,"06m"
,"05m"
,"04m"
,"03m"
,"02m"
, or"01m"
.region (str or list) – The subregion of the grid to load, in the form of a list [xmin, xmax, ymin, ymax] or a string xmin/xmax/ymin/ymax. Required for grids with resolutions higher than 5 arc-minutes (i.e.,
"05m"
).registration (str) – Grid registration type. Either
"pixel"
for pixel registration or"gridline"
for gridline registration. Default is"gridline"
for all resolutions except"01m"
which is"pixel"
only.
- Returns
grid (
xarray.DataArray
) – The Earth vertical gravity gradient grid. Coordinates are latitude and longitude in degrees. Units are in Eotvos.
Note
The
xarray.DataArray
grid doesn’t support slice operation, for Earth vertical gravity gradient grids with resolutions of 5 arc-minutes or higher, which are stored as smaller tiles.