Note
Go to the end to download the full example code.
Reader boundary
Seeding elements around the border of a ocean model domain (NorKyst800) to demonstrate autmatic transition back and forth with another model covering a larger domain (Topaz).
from datetime import datetime
import numpy as np
from opendrift.readers import reader_netCDF_CF_generic
from opendrift.models.oceandrift import OceanDrift
o = OceanDrift(loglevel=20) # Set loglevel to 0 for debug information
# Norkyst
reader_norkyst = reader_netCDF_CF_generic.Reader('https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be')
# Topaz
reader_topaz = reader_netCDF_CF_generic.Reader('https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml')
o.add_reader([reader_norkyst, reader_topaz])
o.set_config('environment:fallback:land_binary_mask', 0)
o.set_config('drift:vertical_mixing', False)
14:10:13 INFO opendrift:568: OpenDriftSimulation initialised (version 1.14.9 / v1.14.9-43-g22dbf7d)
14:10:13 INFO opendrift.readers:64: Opening file with xr.open_dataset
14:10:14 INFO opendrift.readers.reader_netCDF_CF_generic:340: Detected dimensions: {'x': 'X', 'y': 'Y', 'z': 'depth', 'time': 'time'}
14:10:14 INFO opendrift.readers.basereader:178: Variable x_sea_water_velocity will be rotated from eastward_sea_water_velocity
14:10:14 INFO opendrift.readers.basereader:178: Variable y_sea_water_velocity will be rotated from northward_sea_water_velocity
14:10:14 INFO opendrift.readers.basereader:178: Variable x_wind will be rotated from eastward_wind
14:10:14 INFO opendrift.readers.basereader:178: Variable y_wind will be rotated from northward_wind
14:10:14 INFO opendrift.readers:64: Opening file with xr.open_dataset
14:10:17 INFO opendrift.readers.reader_netCDF_CF_generic:340: Detected dimensions: {'x': 'x', 'y': 'y', 'time': 'time'}
Seeding some particles
lons = np.linspace(5, 8, 50)
lats = np.linspace(69.8, 70.8, 50)
lons, lats = np.meshgrid(lons, lats)
Seed oil elements at defined position and time
o.seed_elements(lons, lats, radius=0, number=2500,
time=datetime.now())
14:10:17 INFO opendrift.models.basemodel.environment:203: Adding a global landmask from GSHHG
14:10:21 INFO opendrift.models.basemodel.environment:227: Fallback values will be used for the following variables which have no readers:
14:10:21 INFO opendrift.models.basemodel.environment:230: horizontal_diffusivity: 0.000000
14:10:21 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_significant_height: 0.000000
14:10:21 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_stokes_drift_x_velocity: 0.000000
14:10:21 INFO opendrift.models.basemodel.environment:230: sea_surface_wave_stokes_drift_y_velocity: 0.000000
14:10:21 INFO opendrift.models.basemodel.environment:230: ocean_mixed_layer_thickness: 50.000000
Running model
o.run(steps=16*4, time_step=900, time_step_output=1800)
14:10:21 INFO opendrift:1894: Skipping environment variable ocean_vertical_diffusivity because of condition ['drift:vertical_mixing', 'is', False]
14:10:21 INFO opendrift:1894: Skipping environment variable ocean_mixed_layer_thickness because of condition ['drift:vertical_mixing', 'is', False]
14:10:21 INFO opendrift:1905: Storing previous values of element property lon because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
14:10:21 INFO opendrift:1905: Storing previous values of element property lat because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
14:10:21 INFO opendrift:1913: Storing previous values of environment variable sea_surface_height because of condition ['drift:vertical_advection', 'is', True]
14:10:21 INFO opendrift:947: Using existing reader for land_binary_mask to move elements to ocean
14:10:21 INFO opendrift:978: All points are in ocean
14:10:21 INFO opendrift:2202: 2026-04-21 14:10:17.389620 - step 1 of 64 - 2500 active elements (0 deactivated)
14:10:25 INFO opendrift:2202: 2026-04-21 14:25:17.389620 - step 2 of 64 - 2500 active elements (0 deactivated)
14:10:26 INFO opendrift:2202: 2026-04-21 14:40:17.389620 - step 3 of 64 - 2500 active elements (0 deactivated)
14:10:26 INFO opendrift:2202: 2026-04-21 14:55:17.389620 - step 4 of 64 - 2500 active elements (0 deactivated)
14:10:27 INFO opendrift:2202: 2026-04-21 15:10:17.389620 - step 5 of 64 - 2500 active elements (0 deactivated)
14:10:29 INFO opendrift:2202: 2026-04-21 15:25:17.389620 - step 6 of 64 - 2500 active elements (0 deactivated)
14:10:30 INFO opendrift:2202: 2026-04-21 15:40:17.389620 - step 7 of 64 - 2500 active elements (0 deactivated)
14:10:30 INFO opendrift:2202: 2026-04-21 15:55:17.389620 - step 8 of 64 - 2500 active elements (0 deactivated)
14:10:31 INFO opendrift:2202: 2026-04-21 16:10:17.389620 - step 9 of 64 - 2500 active elements (0 deactivated)
14:10:33 INFO opendrift:2202: 2026-04-21 16:25:17.389620 - step 10 of 64 - 2500 active elements (0 deactivated)
14:10:34 INFO opendrift:2202: 2026-04-21 16:40:17.389620 - step 11 of 64 - 2500 active elements (0 deactivated)
14:10:35 INFO opendrift:2202: 2026-04-21 16:55:17.389620 - step 12 of 64 - 2500 active elements (0 deactivated)
14:10:35 INFO opendrift:2202: 2026-04-21 17:10:17.389620 - step 13 of 64 - 2500 active elements (0 deactivated)
14:10:38 INFO opendrift:2202: 2026-04-21 17:25:17.389620 - step 14 of 64 - 2500 active elements (0 deactivated)
14:10:38 INFO opendrift:2202: 2026-04-21 17:40:17.389620 - step 15 of 64 - 2500 active elements (0 deactivated)
14:10:39 INFO opendrift:2202: 2026-04-21 17:55:17.389620 - step 16 of 64 - 2500 active elements (0 deactivated)
14:10:39 INFO opendrift:2202: 2026-04-21 18:10:17.389620 - step 17 of 64 - 2500 active elements (0 deactivated)
14:10:42 INFO opendrift:2202: 2026-04-21 18:25:17.389620 - step 18 of 64 - 2500 active elements (0 deactivated)
14:10:43 INFO opendrift:2202: 2026-04-21 18:40:17.389620 - step 19 of 64 - 2500 active elements (0 deactivated)
14:10:43 INFO opendrift:2202: 2026-04-21 18:55:17.389620 - step 20 of 64 - 2500 active elements (0 deactivated)
14:10:44 INFO opendrift:2202: 2026-04-21 19:10:17.389620 - step 21 of 64 - 2500 active elements (0 deactivated)
14:10:46 INFO opendrift:2202: 2026-04-21 19:25:17.389620 - step 22 of 64 - 2500 active elements (0 deactivated)
14:10:47 INFO opendrift:2202: 2026-04-21 19:40:17.389620 - step 23 of 64 - 2500 active elements (0 deactivated)
14:10:48 INFO opendrift:2202: 2026-04-21 19:55:17.389620 - step 24 of 64 - 2500 active elements (0 deactivated)
14:10:48 INFO opendrift:2202: 2026-04-21 20:10:17.389620 - step 25 of 64 - 2500 active elements (0 deactivated)
14:10:51 INFO opendrift:2202: 2026-04-21 20:25:17.389620 - step 26 of 64 - 2500 active elements (0 deactivated)
14:10:51 INFO opendrift:2202: 2026-04-21 20:40:17.389620 - step 27 of 64 - 2500 active elements (0 deactivated)
14:10:52 INFO opendrift:2202: 2026-04-21 20:55:17.389620 - step 28 of 64 - 2500 active elements (0 deactivated)
14:10:53 INFO opendrift:2202: 2026-04-21 21:10:17.389620 - step 29 of 64 - 2500 active elements (0 deactivated)
14:10:55 INFO opendrift:2202: 2026-04-21 21:25:17.389620 - step 30 of 64 - 2500 active elements (0 deactivated)
14:10:56 INFO opendrift:2202: 2026-04-21 21:40:17.389620 - step 31 of 64 - 2500 active elements (0 deactivated)
14:10:56 INFO opendrift:2202: 2026-04-21 21:55:17.389620 - step 32 of 64 - 2500 active elements (0 deactivated)
14:10:57 INFO opendrift:2202: 2026-04-21 22:10:17.389620 - step 33 of 64 - 2500 active elements (0 deactivated)
14:10:59 INFO opendrift:2202: 2026-04-21 22:25:17.389620 - step 34 of 64 - 2500 active elements (0 deactivated)
14:11:00 INFO opendrift:2202: 2026-04-21 22:40:17.389620 - step 35 of 64 - 2500 active elements (0 deactivated)
14:11:01 INFO opendrift:2202: 2026-04-21 22:55:17.389620 - step 36 of 64 - 2500 active elements (0 deactivated)
14:11:01 INFO opendrift:2202: 2026-04-21 23:10:17.389620 - step 37 of 64 - 2500 active elements (0 deactivated)
14:11:04 INFO opendrift:2202: 2026-04-21 23:25:17.389620 - step 38 of 64 - 2500 active elements (0 deactivated)
14:11:04 INFO opendrift:2202: 2026-04-21 23:40:17.389620 - step 39 of 64 - 2500 active elements (0 deactivated)
14:11:05 INFO opendrift:2202: 2026-04-21 23:55:17.389620 - step 40 of 64 - 2500 active elements (0 deactivated)
14:11:06 INFO opendrift:2202: 2026-04-22 00:10:17.389620 - step 41 of 64 - 2500 active elements (0 deactivated)
14:11:08 INFO opendrift:2202: 2026-04-22 00:25:17.389620 - step 42 of 64 - 2500 active elements (0 deactivated)
14:11:09 INFO opendrift:2202: 2026-04-22 00:40:17.389620 - step 43 of 64 - 2500 active elements (0 deactivated)
14:11:09 INFO opendrift:2202: 2026-04-22 00:55:17.389620 - step 44 of 64 - 2500 active elements (0 deactivated)
14:11:10 INFO opendrift:2202: 2026-04-22 01:10:17.389620 - step 45 of 64 - 2500 active elements (0 deactivated)
14:11:13 INFO opendrift:2202: 2026-04-22 01:25:17.389620 - step 46 of 64 - 2500 active elements (0 deactivated)
14:11:14 INFO opendrift:2202: 2026-04-22 01:40:17.389620 - step 47 of 64 - 2500 active elements (0 deactivated)
14:11:14 INFO opendrift:2202: 2026-04-22 01:55:17.389620 - step 48 of 64 - 2500 active elements (0 deactivated)
14:11:15 INFO opendrift:2202: 2026-04-22 02:10:17.389620 - step 49 of 64 - 2500 active elements (0 deactivated)
14:11:18 INFO opendrift:2202: 2026-04-22 02:25:17.389620 - step 50 of 64 - 2500 active elements (0 deactivated)
14:11:19 INFO opendrift:2202: 2026-04-22 02:40:17.389620 - step 51 of 64 - 2500 active elements (0 deactivated)
14:11:19 INFO opendrift:2202: 2026-04-22 02:55:17.389620 - step 52 of 64 - 2500 active elements (0 deactivated)
14:11:20 INFO opendrift:2202: 2026-04-22 03:10:17.389620 - step 53 of 64 - 2500 active elements (0 deactivated)
14:11:22 INFO opendrift:2202: 2026-04-22 03:25:17.389620 - step 54 of 64 - 2500 active elements (0 deactivated)
14:11:23 INFO opendrift:2202: 2026-04-22 03:40:17.389620 - step 55 of 64 - 2500 active elements (0 deactivated)
14:11:23 INFO opendrift:2202: 2026-04-22 03:55:17.389620 - step 56 of 64 - 2500 active elements (0 deactivated)
14:11:24 INFO opendrift:2202: 2026-04-22 04:10:17.389620 - step 57 of 64 - 2500 active elements (0 deactivated)
14:11:26 INFO opendrift:2202: 2026-04-22 04:25:17.389620 - step 58 of 64 - 2500 active elements (0 deactivated)
14:11:27 INFO opendrift:2202: 2026-04-22 04:40:17.389620 - step 59 of 64 - 2500 active elements (0 deactivated)
14:11:27 INFO opendrift:2202: 2026-04-22 04:55:17.389620 - step 60 of 64 - 2500 active elements (0 deactivated)
14:11:29 INFO opendrift:2202: 2026-04-22 05:10:17.389620 - step 61 of 64 - 2500 active elements (0 deactivated)
14:11:31 INFO opendrift:2202: 2026-04-22 05:25:17.389620 - step 62 of 64 - 2500 active elements (0 deactivated)
14:11:32 INFO opendrift:2202: 2026-04-22 05:40:17.389620 - step 63 of 64 - 2500 active elements (0 deactivated)
14:11:32 INFO opendrift:2202: 2026-04-22 05:55:17.389620 - step 64 of 64 - 2500 active elements (0 deactivated)
Print and plot results
print(o)
o.animation(fast=True)
===========================
--------------------
Reader performance:
--------------------
https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be
0:00:31.0 total
0:00:00.0 preparing
0:00:30.6 reading
0:00:00.4 interpolation
0:00:00.0 interpolation_time
0:00:00.3 rotating vectors
0:00:00.0 masking
--------------------
https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml
0:00:39.3 total
0:00:00.0 preparing
0:00:39.1 reading
0:00:00.0 interpolation
0:00:00.0 interpolation_time
0:00:00.1 rotating vectors
0:00:00.0 masking
--------------------
global_landmask
0:00:00.0 total
0:00:00.0 preparing
0:00:00.0 reading
0:00:00.0 masking
--------------------
Performance:
1:20.5 total time
8.3 configuration
0.0 preparing main loop
0.0 moving elements to ocean
1:12.1 main loop
0.2 updating elements
0.0 cleaning up
--------------------
===========================
Model: OceanDrift (OpenDrift version 1.14.9)
2500 active Lagrangian3DArray particles (0 deactivated, 0 scheduled)
-------------------
Environment variables:
-----
sea_floor_depth_below_sea_level
sea_surface_height
x_sea_water_velocity
y_sea_water_velocity
1) https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be
2) https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml
-----
upward_sea_water_velocity
x_wind
y_wind
1) https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be
-----
land_binary_mask
1) global_landmask
-----
Readers not added for the following variables:
horizontal_diffusivity
sea_surface_wave_significant_height
sea_surface_wave_stokes_drift_x_velocity
sea_surface_wave_stokes_drift_y_velocity
Discarded readers:
Time:
Start: 2026-04-21 14:10:17.389620 UTC
Present: 2026-04-22 06:10:17.389620 UTC
Calculation steps: 64 * 0:15:00 - total time: 16:00:00
Output steps: 33 * 0:30:00
===========================
14:11:33 WARNING opendrift:2565: Plotting fast. This will make your plots less accurate.
14:11:35 INFO opendrift:4768: Saving animation to /root/project/docs/source/gallery/animations/example_reader_boundary_0.gif...
14:12:00 INFO opendrift:3191: Time to make animation: 0:00:26.670469
o.plot(fast=True)
14:12:00 WARNING opendrift:2565: Plotting fast. This will make your plots less accurate.
(<GeoAxes: title={'center': 'OpenDrift - OceanDrift\n2026-04-21 14:10 to 2026-04-22 06:10 UTC (33 steps)'}>, <Figure size 960.705x1100 with 1 Axes>)
Total running time of the script: (1 minutes 59.897 seconds)