datasets.load_earth_mask: Unexpected display of remote dataset "earth_mask"

[yvonnefroehlich]

Description of the problem

When plotting the dataset earth_mask via pygmt.Figure.grdimage there is a difference between using grid = "@earth_mask_01d_g" and grid = pygmt.datasets.load_earth_mask(). This is not the case for the other remote datasets, e.g. earth_relief.

Minimal Complete Verifiable Example

import pygmt

fig = pygmt.Figure()

with fig.subplot(nrows=2, ncols=2, figsize=("20c", "14c")):

    for i_grid in range(2):
                
        if i_grid == 0:
            grid_at = "@earth_relief_01d_g"
            grid_load = pygmt.datasets.load_earth_relief()
        elif i_grid == 1:
            grid_at = "@earth_mask_01d_g"
            grid_load = pygmt.datasets.load_earth_mask()
        
        # Left column
        fig.grdimage(grid=grid_at, panel=True, frame="+t@" + grid_at)
        
        # Right column
        fig.grdimage(grid=grid_load, panel=True, frame="+tdatasets.load_" + grid_at[1:11])
 
fig.show()
# fig.savefig("datasets_mask_size.png")

Full error message

No error message occurs. The two maps related to the dataset `earth_mask` are expected to be identical.

System information

PyGMT information:
  version: v0.9.1.dev120
System information:
  python: 3.11.4 | packaged by conda-forge | (main, Jun 10 2023, 17:59:51) [MSC v.1935 64 bit (AMD64)]
  executable: C:\ProgramData\Anaconda3\envs\pygmt_env_dev\python.exe
  machine: Windows-10-10.0.19045-SP0
Dependency information:
  numpy: 1.24.3
  pandas: 2.0.2
  xarray: 2023.1.1.dev17
  netCDF4: 1.6.2
  packaging: 23.1
  contextily: 1.3.0
  geopandas: 0.13.2
  IPython: 8.14.0
  rioxarray: 0.14.1
  ghostscript: 9.54.0
GMT library information:
  binary version: 6.4.0
  cores: 4
  grid layout: rows
  image layout: 
  library path: C:/ProgramData/Anaconda3/envs/pygmt_env_dev/Library/bin/gmt.dll
  padding: 2
  plugin dir: C:/ProgramData/Anaconda3/envs/pygmt_env_dev/Library/bin/gmt_plugins
  share dir: C:/Program Files (x86)/gmt6/share
  version: 6.4.0

[seisman]

Confirmed. A fix is available at #2632