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)

16:15:55 INFO    opendrift:576: OpenDriftSimulation initialised (version 1.14.6 / v1.14.6-23-g72ef044)
16:15:55 INFO    opendrift.readers:63: Opening file with xr.open_dataset
16:15:57 INFO    opendrift.readers.reader_netCDF_CF_generic:332: Detected dimensions: {'x': 'X', 'y': 'Y', 'z': 'depth', 'time': 'time'}
16:15:57 INFO    opendrift.readers.basereader:176: Variable x_sea_water_velocity will be rotated from eastward_sea_water_velocity
16:15:57 INFO    opendrift.readers.basereader:176: Variable y_sea_water_velocity will be rotated from northward_sea_water_velocity
16:15:57 INFO    opendrift.readers.basereader:176: Variable x_wind will be rotated from eastward_wind
16:15:57 INFO    opendrift.readers.basereader:176: Variable y_wind will be rotated from northward_wind
16:15:57 INFO    opendrift.readers:63: Opening file with xr.open_dataset
16:15:59 INFO    opendrift.readers.reader_netCDF_CF_generic:332: 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())

16:15:59 INFO    opendrift.models.basemodel.environment:203: Adding a global landmask from GSHHG
16:16:03 INFO    opendrift.models.basemodel.environment:227: Fallback values will be used for the following variables which have no readers:
16:16:03 INFO    opendrift.models.basemodel.environment:230:    sea_surface_wave_significant_height: 0.000000
16:16:03 INFO    opendrift.models.basemodel.environment:230:    sea_surface_wave_stokes_drift_x_velocity: 0.000000
16:16:03 INFO    opendrift.models.basemodel.environment:230:    sea_surface_wave_stokes_drift_y_velocity: 0.000000
16:16:03 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)

16:16:03 INFO    opendrift:1803: Skipping environment variable ocean_vertical_diffusivity because of condition ['drift:vertical_mixing', 'is', False]
16:16:03 INFO    opendrift:1803: Skipping environment variable ocean_mixed_layer_thickness because of condition ['drift:vertical_mixing', 'is', False]
16:16:03 INFO    opendrift:1814: Storing previous values of element property lon because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
16:16:03 INFO    opendrift:1814: Storing previous values of element property lat because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
16:16:03 INFO    opendrift:1822: Storing previous values of environment variable sea_surface_height because of condition ['drift:vertical_advection', 'is', True]
16:16:03 INFO    opendrift:952: Using existing reader for land_binary_mask to move elements to ocean
16:16:03 INFO    opendrift:982: All points are in ocean
16:16:03 INFO    opendrift:2111: 2025-11-27 16:15:59.112394 - step 1 of 64 - 2500 active elements (0 deactivated)
16:16:07 INFO    opendrift:2111: 2025-11-27 16:30:59.112394 - step 2 of 64 - 2500 active elements (0 deactivated)
16:16:08 INFO    opendrift:2111: 2025-11-27 16:45:59.112394 - step 3 of 64 - 2500 active elements (0 deactivated)
16:16:08 INFO    opendrift:2111: 2025-11-27 17:00:59.112394 - step 4 of 64 - 2500 active elements (0 deactivated)
16:16:11 INFO    opendrift:2111: 2025-11-27 17:15:59.112394 - step 5 of 64 - 2500 active elements (0 deactivated)
16:16:11 INFO    opendrift:2111: 2025-11-27 17:30:59.112394 - step 6 of 64 - 2500 active elements (0 deactivated)
16:16:13 INFO    opendrift:2111: 2025-11-27 17:45:59.112394 - step 7 of 64 - 2500 active elements (0 deactivated)
16:16:13 INFO    opendrift:2111: 2025-11-27 18:00:59.112394 - step 8 of 64 - 2500 active elements (0 deactivated)
16:16:15 INFO    opendrift:2111: 2025-11-27 18:15:59.112394 - step 9 of 64 - 2500 active elements (0 deactivated)
16:16:16 INFO    opendrift:2111: 2025-11-27 18:30:59.112394 - step 10 of 64 - 2500 active elements (0 deactivated)
16:16:17 INFO    opendrift:2111: 2025-11-27 18:45:59.112394 - step 11 of 64 - 2500 active elements (0 deactivated)
16:16:17 INFO    opendrift:2111: 2025-11-27 19:00:59.112394 - step 12 of 64 - 2500 active elements (0 deactivated)
16:16:20 INFO    opendrift:2111: 2025-11-27 19:15:59.112394 - step 13 of 64 - 2500 active elements (0 deactivated)
16:16:20 INFO    opendrift:2111: 2025-11-27 19:30:59.112394 - step 14 of 64 - 2500 active elements (0 deactivated)
16:16:21 INFO    opendrift:2111: 2025-11-27 19:45:59.112394 - step 15 of 64 - 2500 active elements (0 deactivated)
16:16:21 INFO    opendrift:2111: 2025-11-27 20:00:59.112394 - step 16 of 64 - 2500 active elements (0 deactivated)
16:16:24 INFO    opendrift:2111: 2025-11-27 20:15:59.112394 - step 17 of 64 - 2500 active elements (0 deactivated)
16:16:24 INFO    opendrift:2111: 2025-11-27 20:30:59.112394 - step 18 of 64 - 2500 active elements (0 deactivated)
16:16:25 INFO    opendrift:2111: 2025-11-27 20:45:59.112394 - step 19 of 64 - 2500 active elements (0 deactivated)
16:16:26 INFO    opendrift:2111: 2025-11-27 21:00:59.112394 - step 20 of 64 - 2500 active elements (0 deactivated)
16:16:28 INFO    opendrift:2111: 2025-11-27 21:15:59.112394 - step 21 of 64 - 2500 active elements (0 deactivated)
16:16:28 INFO    opendrift:2111: 2025-11-27 21:30:59.112394 - step 22 of 64 - 2500 active elements (0 deactivated)
16:16:29 INFO    opendrift:2111: 2025-11-27 21:45:59.112394 - step 23 of 64 - 2500 active elements (0 deactivated)
16:16:30 INFO    opendrift:2111: 2025-11-27 22:00:59.112394 - step 24 of 64 - 2500 active elements (0 deactivated)
16:16:32 INFO    opendrift:2111: 2025-11-27 22:15:59.112394 - step 25 of 64 - 2500 active elements (0 deactivated)
16:16:33 INFO    opendrift:2111: 2025-11-27 22:30:59.112394 - step 26 of 64 - 2500 active elements (0 deactivated)
16:16:33 INFO    opendrift:2111: 2025-11-27 22:45:59.112394 - step 27 of 64 - 2500 active elements (0 deactivated)
16:16:34 INFO    opendrift:2111: 2025-11-27 23:00:59.112394 - step 28 of 64 - 2500 active elements (0 deactivated)
16:16:36 INFO    opendrift:2111: 2025-11-27 23:15:59.112394 - step 29 of 64 - 2500 active elements (0 deactivated)
16:16:37 INFO    opendrift:2111: 2025-11-27 23:30:59.112394 - step 30 of 64 - 2500 active elements (0 deactivated)
16:16:37 INFO    opendrift:2111: 2025-11-27 23:45:59.112394 - step 31 of 64 - 2500 active elements (0 deactivated)
16:16:38 INFO    opendrift:2111: 2025-11-28 00:00:59.112394 - step 32 of 64 - 2500 active elements (0 deactivated)
16:16:40 INFO    opendrift:2111: 2025-11-28 00:15:59.112394 - step 33 of 64 - 2500 active elements (0 deactivated)
16:16:41 INFO    opendrift:2111: 2025-11-28 00:30:59.112394 - step 34 of 64 - 2500 active elements (0 deactivated)
16:16:42 INFO    opendrift:2111: 2025-11-28 00:45:59.112394 - step 35 of 64 - 2500 active elements (0 deactivated)
16:16:42 INFO    opendrift:2111: 2025-11-28 01:00:59.112394 - step 36 of 64 - 2500 active elements (0 deactivated)
16:16:45 INFO    opendrift:2111: 2025-11-28 01:15:59.112394 - step 37 of 64 - 2500 active elements (0 deactivated)
16:16:45 INFO    opendrift:2111: 2025-11-28 01:30:59.112394 - step 38 of 64 - 2500 active elements (0 deactivated)
16:16:46 INFO    opendrift:2111: 2025-11-28 01:45:59.112394 - step 39 of 64 - 2500 active elements (0 deactivated)
16:16:47 INFO    opendrift:2111: 2025-11-28 02:00:59.112394 - step 40 of 64 - 2500 active elements (0 deactivated)
16:16:49 INFO    opendrift:2111: 2025-11-28 02:15:59.112394 - step 41 of 64 - 2500 active elements (0 deactivated)
16:16:50 INFO    opendrift:2111: 2025-11-28 02:30:59.112394 - step 42 of 64 - 2500 active elements (0 deactivated)
16:16:50 INFO    opendrift:2111: 2025-11-28 02:45:59.112394 - step 43 of 64 - 2500 active elements (0 deactivated)
16:16:51 INFO    opendrift:2111: 2025-11-28 03:00:59.112394 - step 44 of 64 - 2500 active elements (0 deactivated)
16:16:53 INFO    opendrift:2111: 2025-11-28 03:15:59.112394 - step 45 of 64 - 2500 active elements (0 deactivated)
16:16:54 INFO    opendrift:2111: 2025-11-28 03:30:59.112394 - step 46 of 64 - 2500 active elements (0 deactivated)
16:16:54 INFO    opendrift:2111: 2025-11-28 03:45:59.112394 - step 47 of 64 - 2500 active elements (0 deactivated)
16:16:55 INFO    opendrift:2111: 2025-11-28 04:00:59.112394 - step 48 of 64 - 2500 active elements (0 deactivated)
16:16:58 INFO    opendrift:2111: 2025-11-28 04:15:59.112394 - step 49 of 64 - 2500 active elements (0 deactivated)
16:16:58 INFO    opendrift:2111: 2025-11-28 04:30:59.112394 - step 50 of 64 - 2500 active elements (0 deactivated)
16:16:59 INFO    opendrift:2111: 2025-11-28 04:45:59.112394 - step 51 of 64 - 2500 active elements (0 deactivated)
16:17:00 INFO    opendrift:2111: 2025-11-28 05:00:59.112394 - step 52 of 64 - 2500 active elements (0 deactivated)
16:17:02 INFO    opendrift:2111: 2025-11-28 05:15:59.112394 - step 53 of 64 - 2500 active elements (0 deactivated)
16:17:03 INFO    opendrift:2111: 2025-11-28 05:30:59.112394 - step 54 of 64 - 2500 active elements (0 deactivated)
16:17:03 INFO    opendrift:2111: 2025-11-28 05:45:59.112394 - step 55 of 64 - 2500 active elements (0 deactivated)
16:17:04 INFO    opendrift:2111: 2025-11-28 06:00:59.112394 - step 56 of 64 - 2500 active elements (0 deactivated)
16:17:06 INFO    opendrift:2111: 2025-11-28 06:15:59.112394 - step 57 of 64 - 2500 active elements (0 deactivated)
16:17:07 INFO    opendrift:2111: 2025-11-28 06:30:59.112394 - step 58 of 64 - 2500 active elements (0 deactivated)
16:17:07 INFO    opendrift:2111: 2025-11-28 06:45:59.112394 - step 59 of 64 - 2500 active elements (0 deactivated)
16:17:08 INFO    opendrift:2111: 2025-11-28 07:00:59.112394 - step 60 of 64 - 2500 active elements (0 deactivated)
16:17:10 INFO    opendrift:2111: 2025-11-28 07:15:59.112394 - step 61 of 64 - 2500 active elements (0 deactivated)
16:17:11 INFO    opendrift:2111: 2025-11-28 07:30:59.112394 - step 62 of 64 - 2500 active elements (0 deactivated)
16:17:12 INFO    opendrift:2111: 2025-11-28 07:45:59.112394 - step 63 of 64 - 2500 active elements (0 deactivated)
16:17:12 INFO    opendrift:2111: 2025-11-28 08:00:59.112394 - 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 2025...
Data variables: (12/21)
    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 ...
    ...                                        ...
    upward_sea_water_velocity                 (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: (12/119)
    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]
    2025-11-27T16:15:59.112394 ... 2...

    standard_name :

    time

    long_name :

    time

    dtype :

    <class 'numpy.float64'>

    array(['2025-11-27T16:15:59.112394000', '2025-11-27T16:45:59.112394000',
           '2025-11-27T17:15:59.112394000', '2025-11-27T17:45:59.112394000',
           '2025-11-27T18:15:59.112394000', '2025-11-27T18:45:59.112394000',
           '2025-11-27T19:15:59.112394000', '2025-11-27T19:45:59.112394000',
           '2025-11-27T20:15:59.112394000', '2025-11-27T20:45:59.112394000',
           '2025-11-27T21:15:59.112394000', '2025-11-27T21:45:59.112394000',
           '2025-11-27T22:15:59.112394000', '2025-11-27T22:45:59.112394000',
           '2025-11-27T23:15:59.112394000', '2025-11-27T23:45:59.112394000',
           '2025-11-28T00:15:59.112394000', '2025-11-28T00:45:59.112394000',
           '2025-11-28T01:15:59.112394000', '2025-11-28T01:45:59.112394000',
           '2025-11-28T02:15:59.112394000', '2025-11-28T02:45:59.112394000',
           '2025-11-28T03:15:59.112394000', '2025-11-28T03:45:59.112394000',
           '2025-11-28T04:15:59.112394000', '2025-11-28T04:45:59.112394000',
           '2025-11-28T05:15:59.112394000', '2025-11-28T05:45:59.112394000',
           '2025-11-28T06:15:59.112394000', '2025-11-28T06:45:59.112394000',
           '2025-11-28T07:15:59.112394000', '2025-11-28T07:45:59.112394000',
           '2025-11-28T08:15:59.112394000'], dtype='datetime64[ns]')

• Data variables: (21)
  • 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 4.999 4.998 ... 7.861 7.853

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_east

    standard_name :

    longitude

    long_name :

    longitude

    axis :

    X

    minval :

    4.9061723

    maxval :

    8.231702

    array([[5.       , 4.9987407, 4.9975243, ..., 4.926134 , 4.923986 ,
            4.921368 ],
           [5.0612245, 5.060293 , 5.0593495, ..., 4.9984307, 4.996612 ,
            4.9942894],
           [5.122449 , 5.1220293, 5.121612 , ..., 5.076876 , 5.0756297,
            5.073862 ],
           ...,
           [7.877551 , 7.870112 , 7.862355 , ..., 7.696501 , 7.6849604,
            7.6736217],
           [7.9387755, 7.932304 , 7.925597 , ..., 7.7929883, 7.784096 ,
            7.7756295],
           [8.       , 7.993966 , 7.987632 , ..., 7.869587 , 7.861103 ,
            7.8532805]], shape=(2500, 33), dtype=float32)

  • lat
    (trajectory, time)
    float32
    69.8 69.8 69.8 ... 70.65 70.65

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_north

    standard_name :

    latitude

    long_name :

    latitude

    axis :

    Y

    minval :

    69.67857

    maxval :

    70.8

    array([[69.8     , 69.797806, 69.7955  , ..., 69.76147 , 69.76059 ,
            69.75961 ],
           [69.8     , 69.79769 , 69.79525 , ..., 69.76089 , 69.759995,
            69.75901 ],
           [69.8     , 69.79768 , 69.79524 , ..., 69.762634, 69.761765,
            69.7608  ],
           ...,
           [70.8     , 70.7895  , 70.77952 , ..., 70.670235, 70.67131 ,
            70.6725  ],
           [70.8     , 70.78942 , 70.7793  , ..., 70.65737 , 70.65738 ,
            70.65748 ],
           [70.8     , 70.78938 , 70.77919 , ..., 70.65384 , 70.65377 ,
            70.65376 ]], 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
    -0.02736 -0.02612 ... -0.1465

    minval :

    -0.3508684

    maxval :

    0.34842527

    array([[-0.02735881, -0.02611594, -0.02632953, ..., -0.04361625,
            -0.05363142, -0.05871857],
           [-0.0200476 , -0.01997154, -0.02135595, ..., -0.03637556,
            -0.04709297, -0.05259312],
           [-0.00916104, -0.00878058, -0.00984007, ..., -0.02402385,
            -0.03507386, -0.04078336],
           ...,
           [-0.16215447, -0.18471867, -0.20366052, ..., -0.23696902,
            -0.22465731, -0.2184306 ],
           [-0.1431018 , -0.16266115, -0.18261574, ..., -0.1823421 ,
            -0.16763332, -0.16020511],
           [-0.1332576 , -0.1544538 , -0.17345381, ..., -0.17396183,
            -0.15588738, -0.1465157 ]], shape=(2500, 33), dtype=float32)

  • y_sea_water_velocity
    (trajectory, time)
    float32
    -0.1345 -0.1411 ... 0.03525 0.04435

    minval :

    -0.43759406

    maxval :

    0.25731996

    array([[-0.1345411 , -0.14105743, -0.1492088 , ..., -0.05281355,
            -0.05909898, -0.06153153],
           [-0.14133239, -0.14917278, -0.15845077, ..., -0.05379111,
            -0.05987601, -0.06214099],
           [-0.14208187, -0.14934154, -0.15782546, ..., -0.05231093,
            -0.05823934, -0.06037442],
           ...,
           [-0.3017572 , -0.28036356, -0.25396457, ...,  0.07723955,
             0.09845895,  0.10841927],
           [-0.30497006, -0.28743258, -0.2623804 , ...,  0.01786924,
             0.03794526,  0.04740194],
           [-0.30622953, -0.29067487, -0.26594722, ...,  0.0160472 ,
             0.03524889,  0.04435395]], shape=(2500, 33), dtype=float32)

  • sea_surface_height
    (trajectory, time)
    float32
    -0.04218 -0.08163 ... -0.5087

    minval :

    -1.0857882

    maxval :

    0.02591765

    array([[-0.04218156, -0.08162585, -0.14294678, ..., -0.48682016,
            -0.55058986, -0.581192  ],
           [-0.04157816, -0.08099454, -0.142318  , ..., -0.48631528,
            -0.5502667 , -0.58096266],
           [-0.04105993, -0.08043606, -0.14171617, ..., -0.48585913,
            -0.54994094, -0.58070177],
           ...,
           [-0.05349519, -0.05636276, -0.08532354, ..., -0.42199308,
            -0.47785515, -0.5062624 ],
           [-0.05576363, -0.05802389, -0.08659776, ..., -0.42229748,
            -0.47813076, -0.50658625],
           [-0.05800326, -0.06009936, -0.08799427, ..., -0.42435625,
            -0.48021215, -0.50868237]], shape=(2500, 33), dtype=float32)

  • x_wind
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... -0.4114 -0.5427

    minval :

    -4.6354995

    maxval :

    6.3959737

    array([[ 0.        ,  0.        ,  0.        , ...,  0.        ,
             0.        ,  0.        ],
           [ 0.        ,  0.        ,  0.        , ...,  0.        ,
             0.        ,  0.        ],
           [ 0.        ,  0.        ,  0.        , ...,  0.        ,
             0.        ,  0.        ],
           ...,
           [ 0.61209965,  1.3863138 ,  2.0484505 , ..., -0.04671665,
            -0.45211583, -0.6709115 ],
           [ 0.60303754,  1.3615618 ,  2.023832  , ..., -0.13148385,
            -0.41957814, -0.58237225],
           [ 0.5810124 ,  1.3339143 ,  1.985798  , ..., -0.18852729,
            -0.41143823, -0.5426611 ]], shape=(2500, 33), dtype=float32)

  • y_wind
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... -1.062 -1.84 -2.172

    minval :

    -17.928581

    maxval :

    0.77233225

    array([[  0.       ,   0.       ,   0.       , ...,   0.       ,
              0.       ,   0.       ],
           [  0.       ,   0.       ,   0.       , ...,   0.       ,
              0.       ,   0.       ],
           [  0.       ,   0.       ,   0.       , ...,   0.       ,
              0.       ,   0.       ],
           ...,
           [-17.8583   , -17.329996 , -16.44653  , ...,  -0.6369153,
             -1.3235649,  -1.62215  ],
           [-17.890324 , -17.382238 , -16.524158 , ...,  -0.9371175,
             -1.6659894,  -1.9763384],
           [-17.924578 , -17.417513 , -16.580763 , ...,  -1.0619096,
             -1.8396894,  -2.1720252]], shape=(2500, 33), dtype=float32)

  • upward_sea_water_velocity
    (trajectory, time)
    float32
    0.0 0.0 ... -2.766e-05 -3.016e-05

    minval :

    -0.0021487628

    maxval :

    0.0019466822

    array([[ 0.0000000e+00,  0.0000000e+00,  0.0000000e+00, ...,
             0.0000000e+00,  0.0000000e+00,  0.0000000e+00],
           [ 0.0000000e+00,  0.0000000e+00,  0.0000000e+00, ...,
             0.0000000e+00,  0.0000000e+00,  0.0000000e+00],
           [ 0.0000000e+00,  0.0000000e+00,  0.0000000e+00, ...,
             0.0000000e+00,  0.0000000e+00,  0.0000000e+00],
           ...,
           [ 2.5619368e-06, -5.3284020e-06, -1.7992603e-05, ...,
            -2.4483950e-05, -2.7664200e-05, -3.0066059e-05],
           [ 4.6715977e-06, -5.3284020e-06, -2.2937285e-05, ...,
            -3.2664200e-05, -3.7664202e-05, -3.9999999e-05],
           [ 2.1977080e-06, -1.2992603e-05, -2.5328402e-05, ...,
            -2.2669352e-05, -2.7664200e-05, -3.0164201e-05]],
          shape=(2500, 33), dtype=float32)

  • sea_surface_wave_significant_height
    (trajectory, time)
    float32
    0.0 0.0 0.0 ... 0.08742 0.1233

    minval :

    0.0

    maxval :

    7.920523

    array([[0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           [0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           [0.        , 0.        , 0.        , ..., 0.        , 0.        ,
            0.        ],
           ...,
           [7.8546205 , 7.4353657 , 6.757239  , ..., 0.01003295, 0.04812332,
            0.07580473],
           [7.882512  , 7.478302  , 6.8177357 , ..., 0.02202874, 0.07260853,
            0.10442875],
           [7.9120507 , 7.5066676 , 6.8600802 , ..., 0.02861458, 0.08742197,
            0.12329949]], 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 ... 2.907e+03

    minval :

    2890.3042

    maxval :

    3248.8118

    array([[3237.6443, 3237.8801, 3238.108 , ..., 3246.9822, 3247.2546,
            3247.4128],
           [3231.7302, 3231.892 , 3232.0845, ..., 3238.6846, 3238.876 ,
            3238.9915],
           [3226.8372, 3226.927 , 3227.0107, ..., 3230.877 , 3230.978 ,
            3231.045 ],
           ...,
           [2909.3318, 2911.8716, 2914.483 , ..., 2940.919 , 2945.65  ,
            2948.0693],
           [2900.6626, 2903.1125, 2905.409 , ..., 2914.5369, 2915.724 ,
            2916.2927],
           [2890.7185, 2893.1042, 2895.3257, ..., 2905.1404, 2906.1094,
            2906.5537]], 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)

• Indexes: (2)
  • trajectory
    PandasIndex

    PandasIndex(Index([   0,    1,    2,    3,    4,    5,    6,    7,    8,    9,
           ...
           2490, 2491, 2492, 2493, 2494, 2495, 2496, 2497, 2498, 2499],
          dtype='int64', name='trajectory', length=2500))

  • time
    PandasIndex

    PandasIndex(DatetimeIndex(['2025-11-27 16:15:59.112394', '2025-11-27 16:45:59.112394',
                   '2025-11-27 17:15:59.112394', '2025-11-27 17:45:59.112394',
                   '2025-11-27 18:15:59.112394', '2025-11-27 18:45:59.112394',
                   '2025-11-27 19:15:59.112394', '2025-11-27 19:45:59.112394',
                   '2025-11-27 20:15:59.112394', '2025-11-27 20:45:59.112394',
                   '2025-11-27 21:15:59.112394', '2025-11-27 21:45:59.112394',
                   '2025-11-27 22:15:59.112394', '2025-11-27 22:45:59.112394',
                   '2025-11-27 23:15:59.112394', '2025-11-27 23:45:59.112394',
                   '2025-11-28 00:15:59.112394', '2025-11-28 00:45:59.112394',
                   '2025-11-28 01:15:59.112394', '2025-11-28 01:45:59.112394',
                   '2025-11-28 02:15:59.112394', '2025-11-28 02:45:59.112394',
                   '2025-11-28 03:15:59.112394', '2025-11-28 03:45:59.112394',
                   '2025-11-28 04:15:59.112394', '2025-11-28 04:45:59.112394',
                   '2025-11-28 05:15:59.112394', '2025-11-28 05:45:59.112394',
                   '2025-11-28 06:15:59.112394', '2025-11-28 06:45:59.112394',
                   '2025-11-28 07:15:59.112394', '2025-11-28 07:45:59.112394',
                   '2025-11-28 08:15:59.112394'],
                  dtype='datetime64[ns]', name='time', freq='30min'))

• Attributes: (119)

  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 2025-11-27 16:16:03.021706

  date_created :

  2025-11-27T16:16:03.021714

  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 :

  2025-11-27 16:15:59.112394

  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: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:horizontal_diffusivity :

  0

  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 :

  1.14.6

  seed_geojson :

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

  simulation_time :

  2025-11-27 16:16:03.028045

  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_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 :

  2025-11-28 08:15:59.112394

  time_coverage_duration :

  P0DT16H0M0S

  time_coverage_resolution :

  P0DT0H15M0S

  performance :

  -------------------- Reader performance: -------------------- https://thredds.met.no/thredds/dodsC/fou-hi/norkystv3_800m_m00_be 0:00:30.3 total 0:00:00.0 preparing 0:00:29.9 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 0:00:40.2 total 0:00:00.0 preparing 0:00:40.0 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: 1:19.2 total time 7.1 configuration 0.0 preparing main loop 0.0 moving elements to ocean 1:12.1 main loop 0.1 updating elements 0.0 cleaning up --------------------

  geospatial_bounds_crs :

  EPSG:4326

  geospatial_bounds_vertical_crs :

  EPSG:5831

  geospatial_lat_min :

  69.67857

  geospatial_lat_max :

  70.8

  geospatial_lat_units :

  degrees_north

  geospatial_lat_resolution :

  point

  geospatial_lon_min :

  4.9061723

  geospatial_lon_max :

  8.231702

  geospatial_lon_units :

  degrees_east

  geospatial_lon_resolution :

  point

  runtime :

  0:01:19.251094

  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
 0:00:30.3  total
 0:00:00.0  preparing
 0:00:29.9  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
 0:00:40.2  total
 0:00:00.0  preparing
 0:00:40.0  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:
 1:19.2 total time
    7.1 configuration
    0.0 preparing main loop
      0.0 moving elements to ocean
 1:12.1 main loop
      0.1 updating elements
    0.0 cleaning up
--------------------
===========================
Model:  OceanDrift     (OpenDrift version 1.14.6)
        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:
  sea_surface_wave_significant_height
  sea_surface_wave_stokes_drift_x_velocity
  sea_surface_wave_stokes_drift_y_velocity

Discarded readers:

Time:
        Start: 2025-11-27 16:15:59.112394 UTC
        Present: 2025-11-28 08:15:59.112394 UTC
        Calculation steps: 64 * 0:15:00 - total time: 16:00:00
        Output steps: 33 * 0:30:00
===========================

16:17:15 WARNING opendrift:2470: Plotting fast. This will make your plots less accurate.
16:17:16 INFO    opendrift:4651: Saving animation to /root/project/docs/source/gallery/animations/example_reader_boundary_0.gif...
16:17:37 INFO    opendrift:3086: Time to make animation: 0:00:22.641649

o.plot(fast=True)

16:17:37 WARNING opendrift:2470: Plotting fast. This will make your plots less accurate.

(<GeoAxes: title={'center': 'OpenDrift - OceanDrift\n2025-11-27 16:15 to 2025-11-28 08:15 UTC (33 steps)'}>, <Figure size 1008.46x1100 with 1 Axes>)