Link to the PyGMT projection table in the Earth relief tutorial

examples/tutorials/advanced/earth_relief.py

@@ -2,39 +2,38 @@
 Plotting Earth relief
 =====================
 
-Plotting a map of Earth relief can use the data accessed by the
-:func:`pygmt.datasets.load_earth_relief` function. The data can then be
-plotted using the :meth:`pygmt.Figure.grdimage` method.
+PyGMT provides the :func:`pygmt.datasets.load_earth_relief` function to download the
+Earth relief data from the GMT remote server and load as an :class:`xarray.DataArray`
+object. The data can then be plotted using the :meth:`pygmt.Figure.grdimage` method.
 """
 
 # %%
 import pygmt
 
 # %%
-# Load sample Earth relief data for the entire globe at a resolution of
-# 1 arc-degree. The other available resolutions are shown at
-# :gmt-datasets:`earth-relief.html`.
+# Load sample Earth relief data for the entire globe at a resolution of 1 arc-degree.
+# Refer to :func:`pygmt.datasets.load_earth_relief` for the other available resolutions.
 grid = pygmt.datasets.load_earth_relief(resolution="01d")
 
 
 # %%
 # Create a plot
 # -------------
 #
-# The :meth:`pygmt.Figure.grdimage` method takes the ``grid`` input to create a
-# figure. It creates and applies a color palette to the figure based upon the
-# z-values of the data. By default, it plots the map with the *turbo* CPT, an
-# equidistant cylindrical projection, and with no frame.
+# The :meth:`pygmt.Figure.grdimage` method takes the ``grid`` input to create a figure.
+# It creates and applies a color palette to the figure based upon the z-values of the
+# data. By default, it plots the map with the *turbo* CPT, an equidistant cylindrical
+# projection, and with no frame.
 
 fig = pygmt.Figure()
 fig.grdimage(grid=grid)
 fig.show()
 
 # %%
-# :meth:`pygmt.Figure.grdimage` can take the optional parameter ``projection``
-# for the map. In the example below, ``projection`` is set to ``"R12c"`` for
-# a 12-centimeters-wide figure with a Winkel Tripel projection. For a list
-# of available projections, see :gmt-docs:`reference/map-projections.html`.
+# :meth:`pygmt.Figure.grdimage` can take the optional parameter ``projection`` for the
+# map. In the example below, ``projection`` is set to ``"R12c"`` for a
+# 12-centimeters-wide figure with a Winkel Tripel projection. For a list of available
+# projections, see :doc:`/techref/projections`.
 
 fig = pygmt.Figure()
 fig.grdimage(grid=grid, projection="R12c")
@@ -45,9 +44,9 @@
 # Set a color map
 # ---------------
 #
-# :meth:`pygmt.Figure.grdimage` takes the ``cmap`` parameter to set the CPT of
-# the figure. Examples of common CPTs for Earth relief are shown below.
-# A full list of CPTs can be found at :gmt-docs:`reference/cpts.html`.
+# :meth:`pygmt.Figure.grdimage` takes the ``cmap`` parameter to set the CPT of the
+# figure. Examples of common CPTs for Earth relief are shown below. A full list of CPTs
+# can be found at :gmt-docs:`reference/cpts.html`.
 
 # %%
 # Using the *geo* CPT:
@@ -68,14 +67,13 @@
 # Add a color bar
 # ---------------
 #
-# The :meth:`pygmt.Figure.colorbar` method displays the CPT and the associated
-# Z-values of the figure, and by default uses the same CPT set by the ``cmap``
-# parameter for :meth:`pygmt.Figure.grdimage`. The ``frame`` parameter for
-# :meth:`pygmt.Figure.colorbar` can be used to set the axis intervals and
-# labels. A list is used to pass multiple arguments to ``frame``. In the
-# example below, ``"a2500"`` sets the axis interval to 2,500,
-# ``"x+lElevation"`` sets the x-axis label, and ``"y+lm"`` sets the y-axis
-# label.
+# The :meth:`pygmt.Figure.colorbar` method displays the CPT and the associated z-values
+# of the figure, and by default uses the same CPT set by the ``cmap`` parameter for
+# :meth:`pygmt.Figure.grdimage`. The ``frame`` parameter for
+# :meth:`pygmt.Figure.colorbar` can be used to set the axis intervals and labels. A list
+# is used to pass multiple arguments to ``frame``. In the example below, ``"a2500"``
+# sets the axis interval to 2,500, ``"x+lElevation"`` sets the x-axis label, and
+# ``"y+lm"`` sets the y-axis label.
 
 fig = pygmt.Figure()
 fig.grdimage(grid=grid, projection="R12c", cmap="geo")
@@ -87,16 +85,14 @@
 # Create a region map
 # -------------------
 #
-# In addition to providing global data, the ``region`` parameter for
-# :func:`pygmt.datasets.load_earth_relief` can be used to provide data for a
-# specific area. The ``region`` parameter is required for resolutions at
-# 5 arc-minutes or higher, and accepts a list (as in the example below) or a
-# string. For the later, the geographic range is passed as
-# "*xmin*/*xmax*/*ymin*/*ymax*".
+# In addition to providing global data, the ``region`` parameter of
+# :func:`pygmt.datasets.load_earth_relief` can be used to provide data for a specific
+# area. The ``region`` parameter is required for resolutions at 5 arc-minutes or higher,
+# and accepts a list in the form of [*xmin*, *xmax*, *ymin*, *ymax*].
 #
-# The example below uses data with a 10 arc-minutes resolution, and plots it on
-# a 15-centimeters-wide figure with a Mercator projection and a CPT set to
-# *geo*. ``frame="a"`` is used to add a frame with annotations to the figure.
+# The example below uses data with a 10 arc-minutes resolution, and plots it on a
+# 15-centimeters-wide figure with a Mercator projection and a CPT set to *geo*.
+# ``frame="a"`` is used to add a frame with annotations to the figure.
 
 grid = pygmt.datasets.load_earth_relief(resolution="10m", region=[-14, 30, 35, 60])
 fig = pygmt.Figure()