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)

17:06:40 INFO    opendrift:569: OpenDriftSimulation initialised (version 1.14.11 / v1.14.12-66-g07283eb)
17:06:40 INFO    opendrift.readers:67: Opening file with xr.open_dataset
17:06:45 INFO    opendrift.readers.reader_netCDF_CF_generic:340: Detected dimensions: {'x': 'X', 'y': 'Y', 'z': 'depth', 'time': 'time'}
17:06:45 INFO    opendrift.readers.basereader:175: Variable x_sea_water_velocity will be rotated from eastward_sea_water_velocity
17:06:45 INFO    opendrift.readers.basereader:175: Variable y_sea_water_velocity will be rotated from northward_sea_water_velocity
17:06:45 INFO    opendrift.readers.basereader:175: Variable x_wind will be rotated from eastward_wind
17:06:45 INFO    opendrift.readers.basereader:175: Variable y_wind will be rotated from northward_wind
17:06:45 INFO    opendrift.readers:67: Opening file with xr.open_dataset
17:06:48 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())

17:06:48 INFO    opendrift.models.basemodel.environment:203: Adding a global landmask from GSHHG
17:06:54 INFO    opendrift.models.basemodel.environment:227: Fallback values will be used for the following variables which have no readers:
17:06:54 INFO    opendrift.models.basemodel.environment:230:    horizontal_diffusivity: 0.000000
17:06:54 INFO    opendrift.models.basemodel.environment:230:    sea_surface_wave_significant_height: 0.000000
17:06:54 INFO    opendrift.models.basemodel.environment:230:    sea_surface_wave_stokes_drift_x_velocity: 0.000000
17:06:54 INFO    opendrift.models.basemodel.environment:230:    sea_surface_wave_stokes_drift_y_velocity: 0.000000
17:06:54 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)

17:06:54 INFO    opendrift:1911: Skipping environment variable ocean_vertical_diffusivity because of condition ['drift:vertical_mixing', 'is', False]
17:06:54 INFO    opendrift:1911: Skipping environment variable ocean_mixed_layer_thickness because of condition ['drift:vertical_mixing', 'is', False]
17:06:54 INFO    opendrift:1922: Storing previous values of element property lon because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
17:06:54 INFO    opendrift:1922: Storing previous values of element property lat because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
17:06:54 INFO    opendrift:1930: Storing previous values of environment variable sea_surface_height because of condition ['drift:vertical_advection', 'is', True]
17:06:54 INFO    opendrift:958: Using existing reader for land_binary_mask to move elements to ocean
17:06:54 INFO    opendrift:990: All points are in ocean
17:06:54 INFO    opendrift:2238: 2026-10-26 17:06:48.810958 - step 1 of 64 - 2500 active elements (0 deactivated)
17:07:00 INFO    opendrift:2238: 2026-10-26 17:21:48.810958 - step 2 of 64 - 2500 active elements (0 deactivated)
17:07:01 INFO    opendrift:2238: 2026-10-26 17:36:48.810958 - step 3 of 64 - 2500 active elements (0 deactivated)
17:07:02 INFO    opendrift:2238: 2026-10-26 17:51:48.810958 - step 4 of 64 - 2500 active elements (0 deactivated)
17:07:02 INFO    opendrift:2238: 2026-10-26 18:06:48.810958 - step 5 of 64 - 2500 active elements (0 deactivated)
17:07:05 INFO    opendrift:2238: 2026-10-26 18:21:48.810958 - step 6 of 64 - 2500 active elements (0 deactivated)
17:07:06 INFO    opendrift:2238: 2026-10-26 18:36:48.810958 - step 7 of 64 - 2500 active elements (0 deactivated)
17:07:06 INFO    opendrift:2238: 2026-10-26 18:51:48.810958 - step 8 of 64 - 2500 active elements (0 deactivated)
17:07:07 INFO    opendrift:2238: 2026-10-26 19:06:48.810958 - step 9 of 64 - 2500 active elements (0 deactivated)
17:07:10 INFO    opendrift:2238: 2026-10-26 19:21:48.810958 - step 10 of 64 - 2500 active elements (0 deactivated)
17:07:10 INFO    opendrift:2238: 2026-10-26 19:36:48.810958 - step 11 of 64 - 2500 active elements (0 deactivated)
17:07:11 INFO    opendrift:2238: 2026-10-26 19:51:48.810958 - step 12 of 64 - 2500 active elements (0 deactivated)
17:07:12 INFO    opendrift:2238: 2026-10-26 20:06:48.810958 - step 13 of 64 - 2500 active elements (0 deactivated)
17:07:14 INFO    opendrift:2238: 2026-10-26 20:21:48.810958 - step 14 of 64 - 2500 active elements (0 deactivated)
17:07:15 INFO    opendrift:2238: 2026-10-26 20:36:48.810958 - step 15 of 64 - 2500 active elements (0 deactivated)
17:07:16 INFO    opendrift:2238: 2026-10-26 20:51:48.810958 - step 16 of 64 - 2500 active elements (0 deactivated)
17:07:16 INFO    opendrift:2238: 2026-10-26 21:06:48.810958 - step 17 of 64 - 2500 active elements (0 deactivated)
17:07:20 INFO    opendrift:2238: 2026-10-26 21:21:48.810958 - step 18 of 64 - 2500 active elements (0 deactivated)
17:07:20 INFO    opendrift:2238: 2026-10-26 21:36:48.810958 - step 19 of 64 - 2500 active elements (0 deactivated)
17:07:21 INFO    opendrift:2238: 2026-10-26 21:51:48.810958 - step 20 of 64 - 2500 active elements (0 deactivated)
17:07:22 INFO    opendrift:2238: 2026-10-26 22:06:48.810958 - step 21 of 64 - 2500 active elements (0 deactivated)
17:07:25 INFO    opendrift:2238: 2026-10-26 22:21:48.810958 - step 22 of 64 - 2500 active elements (0 deactivated)
17:07:25 INFO    opendrift:2238: 2026-10-26 22:36:48.810958 - step 23 of 64 - 2500 active elements (0 deactivated)
17:07:26 INFO    opendrift:2238: 2026-10-26 22:51:48.810958 - step 24 of 64 - 2500 active elements (0 deactivated)
17:07:27 INFO    opendrift:2238: 2026-10-26 23:06:48.810958 - step 25 of 64 - 2500 active elements (0 deactivated)
17:07:30 INFO    opendrift:2238: 2026-10-26 23:21:48.810958 - step 26 of 64 - 2500 active elements (0 deactivated)
17:07:30 INFO    opendrift:2238: 2026-10-26 23:36:48.810958 - step 27 of 64 - 2500 active elements (0 deactivated)
17:07:31 INFO    opendrift:2238: 2026-10-26 23:51:48.810958 - step 28 of 64 - 2500 active elements (0 deactivated)
17:07:32 INFO    opendrift:2238: 2026-10-27 00:06:48.810958 - step 29 of 64 - 2500 active elements (0 deactivated)
17:07:36 INFO    opendrift:2238: 2026-10-27 00:21:48.810958 - step 30 of 64 - 2500 active elements (0 deactivated)
17:07:36 INFO    opendrift:2238: 2026-10-27 00:36:48.810958 - step 31 of 64 - 2500 active elements (0 deactivated)
17:07:37 INFO    opendrift:2238: 2026-10-27 00:51:48.810958 - step 32 of 64 - 2500 active elements (0 deactivated)
17:07:37 INFO    opendrift:2238: 2026-10-27 01:06:48.810958 - step 33 of 64 - 2500 active elements (0 deactivated)
17:07:40 INFO    opendrift:2238: 2026-10-27 01:21:48.810958 - step 34 of 64 - 2500 active elements (0 deactivated)
17:07:41 INFO    opendrift:2238: 2026-10-27 01:36:48.810958 - step 35 of 64 - 2500 active elements (0 deactivated)
17:07:41 INFO    opendrift:2238: 2026-10-27 01:51:48.810958 - step 36 of 64 - 2500 active elements (0 deactivated)
17:07:42 INFO    opendrift:2238: 2026-10-27 02:06:48.810958 - step 37 of 64 - 2500 active elements (0 deactivated)
17:07:44 INFO    opendrift:2238: 2026-10-27 02:21:48.810958 - step 38 of 64 - 2500 active elements (0 deactivated)
17:07:45 INFO    opendrift:2238: 2026-10-27 02:36:48.810958 - step 39 of 64 - 2500 active elements (0 deactivated)
17:07:45 INFO    opendrift:2238: 2026-10-27 02:51:48.810958 - step 40 of 64 - 2500 active elements (0 deactivated)
17:07:46 INFO    opendrift:2238: 2026-10-27 03:06:48.810958 - step 41 of 64 - 2500 active elements (0 deactivated)
17:07:48 INFO    opendrift:2238: 2026-10-27 03:21:48.810958 - step 42 of 64 - 2500 active elements (0 deactivated)
17:07:49 INFO    opendrift:2238: 2026-10-27 03:36:48.810958 - step 43 of 64 - 2500 active elements (0 deactivated)
17:07:50 INFO    opendrift:2238: 2026-10-27 03:51:48.810958 - step 44 of 64 - 2500 active elements (0 deactivated)
17:07:50 INFO    opendrift:2238: 2026-10-27 04:06:48.810958 - step 45 of 64 - 2500 active elements (0 deactivated)
17:07:53 INFO    opendrift:2238: 2026-10-27 04:21:48.810958 - step 46 of 64 - 2500 active elements (0 deactivated)
17:07:53 INFO    opendrift:2238: 2026-10-27 04:36:48.810958 - step 47 of 64 - 2500 active elements (0 deactivated)
17:07:54 INFO    opendrift:2238: 2026-10-27 04:51:48.810958 - step 48 of 64 - 2500 active elements (0 deactivated)
17:07:55 INFO    opendrift:2238: 2026-10-27 05:06:48.810958 - step 49 of 64 - 2500 active elements (0 deactivated)
17:07:57 INFO    opendrift:2238: 2026-10-27 05:21:48.810958 - step 50 of 64 - 2500 active elements (0 deactivated)
17:07:58 INFO    opendrift:2238: 2026-10-27 05:36:48.810958 - step 51 of 64 - 2500 active elements (0 deactivated)
17:07:59 INFO    opendrift:2238: 2026-10-27 05:51:48.810958 - step 52 of 64 - 2500 active elements (0 deactivated)
17:07:59 INFO    opendrift:2238: 2026-10-27 06:06:48.810958 - step 53 of 64 - 2500 active elements (0 deactivated)
17:08:01 INFO    opendrift:2238: 2026-10-27 06:21:48.810958 - step 54 of 64 - 2500 active elements (0 deactivated)
17:08:02 INFO    opendrift:2238: 2026-10-27 06:36:48.810958 - step 55 of 64 - 2500 active elements (0 deactivated)
17:08:02 INFO    opendrift:2238: 2026-10-27 06:51:48.810958 - step 56 of 64 - 2500 active elements (0 deactivated)
17:08:03 INFO    opendrift:2238: 2026-10-27 07:06:48.810958 - step 57 of 64 - 2500 active elements (0 deactivated)
17:08:05 INFO    opendrift:2238: 2026-10-27 07:21:48.810958 - step 58 of 64 - 2500 active elements (0 deactivated)
17:08:06 INFO    opendrift:2238: 2026-10-27 07:36:48.810958 - step 59 of 64 - 2500 active elements (0 deactivated)
17:08:06 INFO    opendrift:2238: 2026-10-27 07:51:48.810958 - step 60 of 64 - 2500 active elements (0 deactivated)
17:08:07 INFO    opendrift:2238: 2026-10-27 08:06:48.810958 - step 61 of 64 - 2500 active elements (0 deactivated)
17:08:09 INFO    opendrift:2238: 2026-10-27 08:21:48.810958 - step 62 of 64 - 2500 active elements (0 deactivated)
17:08:10 INFO    opendrift:2238: 2026-10-27 08:36:48.810958 - step 63 of 64 - 2500 active elements (0 deactivated)
17:08:10 INFO    opendrift:2238: 2026-10-27 08:51:48.810958 - step 64 of 64 - 2500 active elements (0 deactivated)

<xarray.Dataset> Size: 7MB
Dimensions:                                   (trajectory: 2500, time: 33)
Coordinates:
  * trajectory                                (trajectory) int64 20kB 0 ... 2499
  * time                                      (time) datetime64[ns] 264B 2026...
Data variables: (12/22)
    status                                    (trajectory, time) float32 330kB ...
    moving                                    (trajectory, time) float32 330kB ...
    age_seconds                               (trajectory, time) float32 330kB ...
    origin_marker                             (trajectory, time) float32 330kB ...
    lon                                       (trajectory, time) float32 330kB ...
    lat                                       (trajectory, time) float32 330kB ...
    ...                                        ...
    horizontal_diffusivity                    (trajectory, time) float32 330kB ...
    sea_surface_wave_significant_height       (trajectory, time) float32 330kB ...
    sea_surface_wave_stokes_drift_x_velocity  (trajectory, time) float32 330kB ...
    sea_surface_wave_stokes_drift_y_velocity  (trajectory, time) float32 330kB ...
    sea_floor_depth_below_sea_level           (trajectory, time) float32 330kB ...
    land_binary_mask                          (trajectory, time) float32 330kB ...
Attributes: (12/121)
    Conventions:                                                           CF...
    standard_name_vocabulary:                                              CF...
    featureType:                                                           tr...
    title:                                                                 Op...
    summary:                                                               Ou...
    keywords:                                                              tr...
    ...                                                                    ...
    geospatial_lon_units:                                                  de...
    geospatial_lon_resolution:                                             point
    runtime:                                                               0:...
    geospatial_vertical_min:                                               0.0
    geospatial_vertical_max:                                               0.0
    geospatial_vertical_positive:                                          up

xarray.Dataset

• Dimensions:
  • trajectory: 2500
  • time: 33
• Coordinates: (2)
  • trajectory
    (trajectory)
    int64
    0 1 2 3 4 ... 2496 2497 2498 2499

    cf_role :

    trajectory_id

    dtype :

    <class 'numpy.int32'>

    array([   0,    1,    2, ..., 2497, 2498, 2499], shape=(2500,))

  • time
    (time)
    datetime64[ns]
    2026-10-26T17:06:48.810958 ... 2...

    standard_name :

    time

    long_name :

    time

    dtype :

    <class 'numpy.float64'>

    array(['2026-10-26T17:06:48.810958000', '2026-10-26T17:36:48.810958000',
           '2026-10-26T18:06:48.810958000', '2026-10-26T18:36:48.810958000',
           '2026-10-26T19:06:48.810958000', '2026-10-26T19:36:48.810958000',
           '2026-10-26T20:06:48.810958000', '2026-10-26T20:36:48.810958000',
           '2026-10-26T21:06:48.810958000', '2026-10-26T21:36:48.810958000',
           '2026-10-26T22:06:48.810958000', '2026-10-26T22:36:48.810958000',
           '2026-10-26T23:06:48.810958000', '2026-10-26T23:36:48.810958000',
           '2026-10-27T00:06:48.810958000', '2026-10-27T00:36:48.810958000',
           '2026-10-27T01:06:48.810958000', '2026-10-27T01:36:48.810958000',
           '2026-10-27T02:06:48.810958000', '2026-10-27T02:36:48.810958000',
           '2026-10-27T03:06:48.810958000', '2026-10-27T03:36:48.810958000',
           '2026-10-27T04:06:48.810958000', '2026-10-27T04:36:48.810958000',
           '2026-10-27T05:06:48.810958000', '2026-10-27T05:36:48.810958000',
           '2026-10-27T06:06:48.810958000', '2026-10-27T06:36:48.810958000',
           '2026-10-27T07:06:48.810958000', '2026-10-27T07:36:48.810958000',
           '2026-10-27T08:06:48.810958000', '2026-10-27T08:36:48.810958000',
           '2026-10-27T09:06:48.810958000'], dtype='datetime64[ns]')

• Data variables: (22)
  • status
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    dtype :

    <class 'numpy.int32'>

    valid_range :

    [0 0]

    flag_values :

    [0]

    flag_meanings :

    active

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • moving
    (trajectory, time)
    float32
    1.0 1.0 1.0 1.0 ... 1.0 1.0 1.0 1.0

    dtype :

    <class 'numpy.int32'>

    minval :

    1

    maxval :

    1

    array([[1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.],
           ...,
           [1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.]], shape=(2500, 33), dtype=float32)

  • age_seconds
    (trajectory, time)
    float32
    0.0 1.8e+03 ... 5.58e+04 5.76e+04

    dtype :

    <class 'numpy.float32'>

    units :

    s

    minval :

    0.0

    maxval :

    57600.0

    array([[    0.,  1800.,  3600., ..., 54000., 55800., 57600.],
           [    0.,  1800.,  3600., ..., 54000., 55800., 57600.],
           [    0.,  1800.,  3600., ..., 54000., 55800., 57600.],
           ...,
           [    0.,  1800.,  3600., ..., 54000., 55800., 57600.],
           [    0.,  1800.,  3600., ..., 54000., 55800., 57600.],
           [    0.,  1800.,  3600., ..., 54000., 55800., 57600.]],
          shape=(2500, 33), dtype=float32)

  • origin_marker
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    dtype :

    <class 'numpy.int32'>

    unit :

    description :

    An integer kept constant during the simulation. Different values may be used for different seedings, to separate elements during analysis. With GUI, only a single seeding is possible.

    flag_values :

    [0]

    flag_meanings :

    Seed_0

    minval :

    0

    maxval :

    0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • lon
    (trajectory, time)
    float32
    5.0 4.997 4.995 ... 7.854 7.848

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_east

    standard_name :

    longitude

    long_name :

    longitude

    axis :

    X

    minval :

    4.8906407

    maxval :

    8.0

    array([[5.       , 4.997383 , 4.9945436, ..., 4.991331 , 4.9889517,
            4.986921 ],
           [5.0612245, 5.058816 , 5.056192 , ..., 5.0579824, 5.055911 ,
            5.054191 ],
           [5.122449 , 5.120183 , 5.1177073, ..., 5.1221857, 5.1203074,
            5.118778 ],
           ...,
           [7.877551 , 7.8729987, 7.86934  , ..., 7.7428527, 7.7382283,
            7.733063 ],
           [7.9387755, 7.934269 , 7.930565 , ..., 7.8010793, 7.7961016,
            7.7906017],
           [8.       , 7.9955287, 7.991865 , ..., 7.8591866, 7.853748 ,
            7.8477793]], shape=(2500, 33), dtype=float32)

  • lat
    (trajectory, time)
    float32
    69.8 69.8 69.8 ... 70.74 70.73

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_north

    standard_name :

    latitude

    long_name :

    latitude

    axis :

    Y

    minval :

    69.76677

    maxval :

    70.83279

    array([[69.8     , 69.80021 , 69.80057 , ..., 69.827965, 69.829155,
            69.830696],
           [69.8     , 69.80017 , 69.8005  , ..., 69.82711 , 69.82829 ,
            69.8298  ],
           [69.8     , 69.80013 , 69.80041 , ..., 69.825905, 69.82703 ,
            69.828476],
           ...,
           [70.8     , 70.79821 , 70.79629 , ..., 70.744705, 70.74283 ,
            70.74101 ],
           [70.8     , 70.79804 , 70.795944, ..., 70.74194 , 70.73997 ,
            70.73808 ],
           [70.8     , 70.79792 , 70.79567 , ..., 70.738434, 70.73629 ,
            70.73425 ]], shape=(2500, 33), dtype=float32)

  • z
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    dtype :

    <class 'numpy.float32'>

    units :

    m

    standard_name :

    z

    long_name :

    vertical position

    axis :

    Z

    positive :

    up

    minval :

    0.0

    maxval :

    0.0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • wind_drift_factor
    (trajectory, time)
    float32
    0.02 0.02 0.02 ... 0.02 0.02 0.02

    dtype :

    <class 'numpy.float32'>

    units :

    1

    description :

    Elements at surface are moved with this fraction of the vind vector, in addition to currents and Stokes drift

    minval :

    0.02

    maxval :

    0.02

    array([[0.02, 0.02, 0.02, ..., 0.02, 0.02, 0.02],
           [0.02, 0.02, 0.02, ..., 0.02, 0.02, 0.02],
           [0.02, 0.02, 0.02, ..., 0.02, 0.02, 0.02],
           ...,
           [0.02, 0.02, 0.02, ..., 0.02, 0.02, 0.02],
           [0.02, 0.02, 0.02, ..., 0.02, 0.02, 0.02],
           [0.02, 0.02, 0.02, ..., 0.02, 0.02, 0.02]],
          shape=(2500, 33), dtype=float32)

  • current_drift_factor
    (trajectory, time)
    float32
    1.0 1.0 1.0 1.0 ... 1.0 1.0 1.0 1.0

    dtype :

    <class 'numpy.float32'>

    units :

    1

    description :

    Elements are moved with this fraction of the current vector, in addition to currents and Stokes drift

    minval :

    1.0

    maxval :

    1.0

    array([[1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.],
           ...,
           [1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.],
           [1., 1., 1., ..., 1., 1., 1.]], shape=(2500, 33), dtype=float32)

  • terminal_velocity
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    dtype :

    <class 'numpy.float32'>

    units :

    m/s

    description :

    Terminal rise/sinking velocity (buoyancy) in the ocean column

    minval :

    0.0

    maxval :

    0.0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • x_sea_water_velocity
    (trajectory, time)
    float32
    -0.05443 -0.06005 ... -0.02261

    minval :

    -0.17667556

    maxval :

    0.22081882

    array([[-0.05442923, -0.06004988, -0.06230638, ..., -0.05241202,
            -0.04561711, -0.0412653 ],
           [-0.05002768, -0.05544987, -0.05765552, ..., -0.04585705,
            -0.03897027, -0.03459739],
           [-0.04701502, -0.05228984, -0.0544326 , ..., -0.04173618,
            -0.03486438, -0.03054996],
           ...,
           [ 0.0018676 ,  0.00523977,  0.00812712, ...,  0.00141432,
            -0.0018388 , -0.00355061],
           [ 0.0026299 ,  0.00414784,  0.00484474, ..., -0.00694672,
            -0.00955122, -0.01096241],
           [ 0.00325269,  0.00469139,  0.00501059, ..., -0.01834561,
            -0.02101429, -0.02260863]], shape=(2500, 33), dtype=float32)

  • y_sea_water_velocity
    (trajectory, time)
    float32
    0.01066 0.0194 ... -0.1406 -0.1374

    minval :

    -0.22748464

    maxval :

    0.24563093

    array([[ 0.01065887,  0.01939516,  0.03177133, ...,  0.06855316,
             0.09009643,  0.10055429],
           [ 0.00866132,  0.01728123,  0.02941041, ...,  0.06767023,
             0.08861361,  0.09877233],
           [ 0.00590026,  0.014534  ,  0.02662301, ...,  0.06441236,
             0.08482543,  0.09475615],
           ...,
           [-0.11950913, -0.12742004, -0.1346376 , ..., -0.12978591,
            -0.12822428, -0.12745497],
           [-0.1303632 , -0.13930002, -0.14719337, ..., -0.136462  ,
            -0.13239275, -0.13038738],
           [-0.1387107 , -0.14927202, -0.15881218, ..., -0.14726092,
            -0.14062789, -0.13737199]], shape=(2500, 33), dtype=float32)

  • sea_surface_height
    (trajectory, time)
    float32
    -1.188 -1.187 ... -0.8845 -0.7902

    minval :

    -1.4538999

    maxval :

    0.24846452

    array([[-1.1878185 , -1.1869776 , -1.1410336 , ..., -0.8133039 ,
            -0.62128145, -0.5243759 ],
           [-1.1869172 , -1.1861427 , -1.1401708 , ..., -0.812366  ,
            -0.62006366, -0.52300155],
           [-1.1862569 , -1.1855441 , -1.1395371 , ..., -0.8113699 ,
            -0.6188283 , -0.52162975],
           ...,
           [-1.1783631 , -1.2054977 , -1.2114238 , ..., -1.0647225 ,
            -0.87663615, -0.7826047 ],
           [-1.1825475 , -1.2096984 , -1.215794  , ..., -1.0686094 ,
            -0.8802016 , -0.78598785],
           [-1.1871867 , -1.2146056 , -1.2205935 , ..., -1.0731485 ,
            -0.88452387, -0.79023004]], shape=(2500, 33), dtype=float32)

  • x_wind
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... -4.918 -5.116

    minval :

    -7.036008

    maxval :

    1.5487664

    array([[ 0.       ,  0.       ,  0.       , ...,  0.       ,  0.       ,
             0.       ],
           [ 0.       ,  0.       ,  0.       , ...,  0.       ,  0.       ,
             0.       ],
           [ 0.       ,  0.       ,  0.       , ...,  0.       ,  0.       ,
             0.       ],
           ...,
           [-4.961653 , -4.2250295, -3.609126 , ..., -4.6636634, -5.0524936,
            -5.24583  ],
           [-4.9322414, -4.1912465, -3.5804265, ..., -4.612005 , -5.0146155,
            -5.213776 ],
           [-4.927825 , -4.179545 , -3.567522 , ..., -4.5152426, -4.918326 ,
            -5.1160264]], shape=(2500, 33), dtype=float32)

  • y_wind
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... 0.6394 0.6478

    minval :

    -2.832986

    maxval :

    5.8341527

    array([[0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           [0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           [0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           ...,
           [0.51512766, 0.51563114, 0.4631527 , ..., 0.6300601 , 0.7269301 ,
            0.7834686 ],
           [0.5639674 , 0.5651083 , 0.5275659 , ..., 0.63832974, 0.70273685,
            0.74250025],
           [0.61248267, 0.61093867, 0.58182174, ..., 0.6347896 , 0.6393602 ,
            0.6478344 ]], shape=(2500, 33), dtype=float32)

  • upward_sea_water_velocity
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... 0.0001023 0.0001073

    minval :

    -0.0040744315

    maxval :

    0.001031627

    array([[ 0.00000000e+00,  0.00000000e+00,  0.00000000e+00, ...,
             0.00000000e+00,  0.00000000e+00,  0.00000000e+00],
           [ 0.00000000e+00,  0.00000000e+00,  0.00000000e+00, ...,
             0.00000000e+00,  0.00000000e+00,  0.00000000e+00],
           [ 0.00000000e+00,  0.00000000e+00,  0.00000000e+00, ...,
             0.00000000e+00,  0.00000000e+00,  0.00000000e+00],
           ...,
           [-3.43220709e-05, -9.32206967e-06,  1.56779297e-05, ...,
             9.89208347e-05,  1.09865825e-04,  1.15043193e-04],
           [-3.43220709e-05, -9.32206967e-06,  1.56779297e-05, ...,
             8.50955039e-05,  9.94184957e-05,  1.06325831e-04],
           [-3.43220709e-05, -9.32206967e-06,  1.56779297e-05, ...,
             9.22711697e-05,  1.02271166e-04,  1.07271168e-04]],
          shape=(2500, 33), dtype=float32)

  • horizontal_diffusivity
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    minval :

    0.0

    maxval :

    0.0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • sea_surface_wave_significant_height
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... 0.6051 0.6542

    minval :

    0.0

    maxval :

    1.2254924

    array([[0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           [0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           [0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           ...,
           [0.6121306 , 0.44567195, 0.3257114 , ..., 0.5448096 , 0.6409805 ,
            0.6920609 ],
           [0.60626864, 0.43999296, 0.32220533, ..., 0.5332802 , 0.63074905,
            0.68227524],
           [0.6066014 , 0.43890926, 0.32141697, ..., 0.51144314, 0.6051283 ,
            0.654198  ]], shape=(2500, 33), dtype=float32)

  • sea_surface_wave_stokes_drift_x_velocity
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    minval :

    0.0

    maxval :

    0.0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • sea_surface_wave_stokes_drift_y_velocity
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    minval :

    0.0

    maxval :

    0.0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

  • sea_floor_depth_below_sea_level
    (trajectory, time)
    float32
    3.238e+03 3.238e+03 ... 2.922e+03

    minval :

    2890.3044

    maxval :

    3239.0674

    array([[3237.644 , 3237.9062, 3238.1855, ..., 3235.8394, 3235.9248,
            3235.9404],
           [3231.7295, 3231.9263, 3232.1367, ..., 3230.1284, 3230.1528,
            3230.1392],
           [3226.8374, 3227.0083, 3227.1924, ..., 3225.4707, 3225.5103,
            3225.5122],
           ...,
           [2909.3315, 2910.175 , 2910.9224, ..., 2942.4875, 2944.1643,
            2945.0452],
           [2900.6636, 2901.6345, 2902.4873, ..., 2931.9204, 2933.374 ,
            2934.1384],
           [2890.7188, 2891.7515, 2892.6594, ..., 2920.5752, 2921.8086,
            2922.4727]], shape=(2500, 33), dtype=float32)

  • land_binary_mask
    (trajectory, time)
    float32
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    minval :

    0.0

    maxval :

    0.0

    array([[0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           ...,
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.],
           [0., 0., 0., ..., 0., 0., 0.]], shape=(2500, 33), dtype=float32)

• Attributes: (121)

  Conventions :

  CF-1.11, ACDD-1.3

  standard_name_vocabulary :

  CF Standard Name Table v85

  featureType :

  trajectory

  title :

  OpenDrift trajectory simulation

  summary :

  Output from simulation with OpenDrift framework

  keywords :

  trajectory, drift, lagrangian, simulation

  history :

  Created 2026-10-26 17:06:54.845091

  date_created :

  2026-10-26T17:06:54.845103

  source :

  Output from simulation with OpenDrift

  model_url :

  https://github.com/OpenDrift/opendrift

  opendrift_class :

  OceanDrift

  opendrift_module :

  opendrift.models.oceandrift

  readers :

  odict_keys(['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be', 'https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml', 'global_landmask'])

  time_coverage_start :

  2026-10-26 17:06:48.810958

  time_step_calculation :

  0:15:00

  time_step_output :

  0:30:00

  config_environment:constant:x_sea_water_velocity :

  None

  config_environment:fallback:x_sea_water_velocity :

  0

  config_environment:constant:y_sea_water_velocity :

  None

  config_environment:fallback:y_sea_water_velocity :

  0

  config_environment:constant:sea_surface_height :

  None

  config_environment:fallback:sea_surface_height :

  0

  config_environment:constant:x_wind :

  None

  config_environment:fallback:x_wind :

  0

  config_environment:constant:y_wind :

  None

  config_environment:fallback:y_wind :

  0

  config_environment:constant:upward_sea_water_velocity :

  None

  config_environment:fallback:upward_sea_water_velocity :

  0

  config_environment:constant:ocean_vertical_diffusivity :

  None

  config_environment:fallback:ocean_vertical_diffusivity :

  0

  config_environment:constant:horizontal_diffusivity :

  None

  config_environment:fallback:horizontal_diffusivity :

  0

  config_environment:constant:sea_surface_wave_significant_height :

  None

  config_environment:fallback:sea_surface_wave_significant_height :

  0

  config_environment:constant:sea_surface_wave_stokes_drift_x_velocity :

  None

  config_environment:fallback:sea_surface_wave_stokes_drift_x_velocity :

  0

  config_environment:constant:sea_surface_wave_stokes_drift_y_velocity :

  None

  config_environment:fallback:sea_surface_wave_stokes_drift_y_velocity :

  0

  config_environment:constant:ocean_mixed_layer_thickness :

  None

  config_environment:fallback:ocean_mixed_layer_thickness :

  50

  config_environment:constant:sea_floor_depth_below_sea_level :

  None

  config_environment:fallback:sea_floor_depth_below_sea_level :

  10000

  config_environment:constant:land_binary_mask :

  None

  config_environment:fallback:land_binary_mask :

  0.0

  config_general:use_auto_landmask :

  True

  config_drift:current_uncertainty :

  0

  config_drift:current_uncertainty_uniform :

  0

  config_drift:max_speed :

  2.0

  config_readers:max_number_of_fails :

  1

  config_general:simulation_name :

  config_general:coastline_action :

  stranding

  config_general:coastline_approximation_precision :

  0.001

  config_general:time_step_minutes :

  60

  config_general:time_step_output_minutes :

  None

  config_seed:ocean_only :

  True

  config_seed:number :

  1

  config_drift:max_age_seconds :

  None

  config_drift:advection_scheme :

  euler

  config_drift:profiles_depth :

  50

  config_drift:wind_uncertainty :

  0

  config_drift:relative_wind :

  False

  config_drift:deactivate_north_of :

  None

  config_drift:deactivate_south_of :

  None

  config_drift:deactivate_east_of :

  None

  config_drift:deactivate_west_of :

  None

  config_seed:origin_marker :

  0

  config_seed:z :

  0

  config_seed:wind_drift_factor :

  0.02

  config_seed:current_drift_factor :

  1

  config_seed:terminal_velocity :

  0.0

  config_drift:vertical_advection :

  True

  config_drift:vertical_advection_at_surface :

  False

  config_drift:water_column_stretching :

  False

  config_drift:vertical_advection_correction :

  False

  config_drift:vertical_mixing :

  False

  config_drift:vertical_mixing_at_surface :

  False

  config_vertical_mixing:timestep :

  60

  config_vertical_mixing:diffusivitymodel :

  environment

  config_vertical_mixing:background_diffusivity :

  1.2e-05

  config_vertical_mixing:TSprofiles :

  False

  config_drift:wind_drift_depth :

  0.1

  config_drift:stokes_drift :

  True

  config_drift:stokes_drift_profile :

  Phillips

  config_drift:use_tabularised_stokes_drift :

  False

  config_drift:tabularised_stokes_drift_fetch :

  25000

  config_general:seafloor_action :

  lift_to_seafloor

  config_drift:truncate_ocean_model_below_m :

  None

  config_seed:seafloor :

  False

  opendrift_version :

  1.14.11

  seed_geojson :

  {"features": [], "type": "FeatureCollection"}

  simulation_time :

  2026-10-26 17:06:54.854420

  reader_x_sea_water_velocity :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be', 'https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml']

  reader_y_sea_water_velocity :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be', 'https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml']

  reader_sea_surface_height :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be', 'https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml']

  reader_x_wind :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be']

  reader_y_wind :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be']

  reader_upward_sea_water_velocity :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be']

  reader_horizontal_diffusivity :

  0

  reader_sea_surface_wave_significant_height :

  0

  reader_sea_surface_wave_stokes_drift_x_velocity :

  0

  reader_sea_surface_wave_stokes_drift_y_velocity :

  0

  reader_sea_floor_depth_below_sea_level :

  ['https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be', 'https://thredds.met.no/thredds/dodsC/cmems/topaz6/dataset-topaz6-arc-15min-3km-be.ncml']

  reader_land_binary_mask :

  ['global_landmask']

  time_coverage_end :

  2026-10-27 09:06:48.810958

  time_coverage_duration :

  P0DT16H0M0S

  time_coverage_resolution :

  P0DT0H15M0S

  performance :

  -------------------- Reader performance: -------------------- https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be 0:00:35.2 total 0:00:00.0 preparing 0:00:34.8 reading 0:00:00.3 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 0:00:39.2 total 0:00:00.0 preparing 0:00:39.0 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: 1:31.1 total time 14.5 configuration 0.0 preparing main loop 0.0 moving elements to ocean 1:16.5 main loop 0.2 updating elements 0.0 cleaning up --------------------

  geospatial_bounds_crs :

  EPSG:4326

  geospatial_bounds_vertical_crs :

  EPSG:5831

  geospatial_lat_min :

  69.76677

  geospatial_lat_max :

  70.83279

  geospatial_lat_units :

  degrees_north

  geospatial_lat_resolution :

  point

  geospatial_lon_min :

  4.8906407

  geospatial_lon_max :

  8.0

  geospatial_lon_units :

  degrees_east

  geospatial_lon_resolution :

  point

  runtime :

  0:01:31.130750

  geospatial_vertical_min :

  0.0

  geospatial_vertical_max :

  0.0

  geospatial_vertical_positive :

  up

Print and plot results

print(o)
o.animation(fast=True)

===========================
--------------------
Reader performance:
--------------------
https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be
 0:00:35.2  total
 0:00:00.0  preparing
 0:00:34.8  reading
 0:00:00.3  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
 0:00:39.2  total
 0:00:00.0  preparing
 0:00:39.0  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:
 1:31.1 total time
   14.5 configuration
    0.0 preparing main loop
      0.0 moving elements to ocean
 1:16.5 main loop
      0.2 updating elements
    0.0 cleaning up
--------------------
===========================
Model:  OceanDrift     (OpenDrift version 1.14.11)
        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: 2026-10-26 17:06:48.810958 UTC
        Present: 2026-10-27 09:06:48.810958 UTC
        Calculation steps: 64 * 0:15:00 - total time: 16:00:00
        Output steps: 33 * 0:30:00
===========================

17:08:11 WARNING opendrift:2614: Plotting fast. This will make your plots less accurate.
17:08:13 INFO    opendrift:4889: Saving animation to /root/project/docs/source/gallery/animations/example_reader_boundary_0.gif...
17:08:26 INFO    opendrift:3297: Time to make animation: 0:00:14.777917

o.plot(fast=True)

17:08:26 WARNING opendrift:2614: Plotting fast. This will make your plots less accurate.

(<GeoAxes: title={'center': 'OpenDrift - OceanDrift\n2026-10-26 17:06 to 2026-10-27 09:06 UTC (33 steps)'}>, <Figure size 922.928x1100 with 1 Axes>)