Add 1km to make_land

Add binary closing to land_large (with large kernel
in convolution, it makes holes a few pixels large)

Compute/make_land.py

@@ -3,10 +3,12 @@
 import numpy as np
 import xarray as xr
 
+from global_land_mask import globe
 from scipy import ndimage as nd
 
 import lib
 import lib.data.globcolour
+import lib.data.modis
 import lib.data.ostia
 import lib.zones
 
@@ -15,6 +17,7 @@ def main():
     args = lib.get_args(['region'])
     make_land(args)
 
+
 def get_filename(grid, args):
     filename = lib.zones.get_filename('land_mask', args, grid=grid)
     print(filename)
@@ -25,7 +28,8 @@ def write_land(ds, land, filename, grid):
     ds = ds.drop_vars(ds.data_vars)
     ds.attrs = dict(grid=grid)
     ds['land'] = land
-    ds = ds.isel(time=0)
+    if 'time' in ds.land.dims:
+        ds = ds.isel(time=0)
     ds = enlarge(ds)
     ds.to_netcdf(filename, encoding={'land': {'zlib': True}})
     return ds
@@ -45,10 +49,28 @@ def enlarge(ds):
         input_core_dims=[['lat', 'lon']],
         output_core_dims=[['lat', 'lon']],
         kwargs=dict(weights=kernel, mode='nearest'))
+    ds['closed'] = xr.apply_ufunc(
+        nd.binary_closing, ds['land_large'],
+        input_core_dims=[['lat', 'lon']],
+        output_core_dims=[['lat', 'lon']]
+    )
+    ds['land_large'] = ds['land_large'] | ds['closed']
+    ds.drop_vars('closed')
     return ds
 
 
 def make_land(args):
+    # 1km
+    grid = '1km'
+    filename = get_filename(grid, args)
+
+    finder = lib.data.modis.get_finder(args)
+    ds = xr.open_dataset(finder.get_files()[0])
+    lon_grid, lat_grid = np.meshgrid(ds.lon.values, ds.lat.values)
+    land = globe.is_land(lat_grid, lon_grid)
+    ds['land'] = (['lat', 'lon'], land)
+    write_land(ds, ds['land'], filename, grid)
+
     # EPSG32662
     grid = '4km_EPSG32662'
     filename = get_filename(grid, args)

README.md

@@ -28,4 +28,5 @@ root_data: /...
     shapely
     xarray
     filefinder
+    global-land-mask