Convolve input

Decreasing the spatial resolution of fields from a reader by convolution. This may improve accuracy, see: https://doi.org/10.1016/j.rse.2019.01.001

from datetime import datetime, timedelta
import matplotlib.pyplot as plt
from opendrift import test_data_folder as tdf
from opendrift.readers import reader_netCDF_CF_generic
from opendrift.models.oceandrift import OceanDrift


lon = 4.9; lat = 60.0
o = OceanDrift(loglevel=20)

reader_norkyst = reader_netCDF_CF_generic.Reader(tdf + '16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc')
time = reader_norkyst.start_time

o.add_reader([reader_norkyst])
o.seed_elements(lon, lat, radius=1000, number=1000, time=time)
o.run(steps=20)

17:19:46 INFO    opendrift:513: OpenDriftSimulation initialised (version 1.14.2 / v1.14.2-88-gf09b7bd)
17:19:46 INFO    opendrift.readers:61: Opening file with xr.open_dataset
17:19:46 INFO    opendrift.readers.reader_netCDF_CF_generic:332: Detected dimensions: {'x': 'X', 'y': 'Y', 'z': 'depth', 'time': 'time'}
17:19:46 INFO    opendrift.models.basemodel.environment:206: Adding a global landmask from GSHHG
17:19:50 INFO    opendrift.models.basemodel.environment:229: Fallback values will be used for the following variables which have no readers:
17:19:50 INFO    opendrift.models.basemodel.environment:232:    sea_surface_height: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    x_wind: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    y_wind: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    upward_sea_water_velocity: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    ocean_vertical_diffusivity: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    sea_surface_wave_significant_height: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    sea_surface_wave_stokes_drift_x_velocity: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    sea_surface_wave_stokes_drift_y_velocity: 0.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    ocean_mixed_layer_thickness: 50.000000
17:19:50 INFO    opendrift.models.basemodel.environment:232:    sea_floor_depth_below_sea_level: 10000.000000
17:19:50 INFO    opendrift:1732: Skipping environment variable ocean_vertical_diffusivity because of condition ['drift:vertical_mixing', 'is', False]
17:19:50 INFO    opendrift:1732: Skipping environment variable ocean_mixed_layer_thickness because of condition ['drift:vertical_mixing', 'is', False]
17:19:50 INFO    opendrift:1743: Storing previous values of element property lon because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
17:19:50 INFO    opendrift:1743: Storing previous values of element property lat because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
17:19:50 INFO    opendrift:1751: Storing previous values of environment variable sea_surface_height because of condition ['drift:vertical_advection', 'is', True]
17:19:50 INFO    opendrift:899: Using existing reader for land_binary_mask
17:19:50 INFO    opendrift:928: All points are in ocean
17:19:50 INFO    opendrift:2035: 2015-11-16 00:00:00 - step 1 of 20 - 1000 active elements (0 deactivated)
17:19:50 INFO    opendrift:2035: 2015-11-16 01:00:00 - step 2 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 02:00:00 - step 3 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 03:00:00 - step 4 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 04:00:00 - step 5 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 05:00:00 - step 6 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 06:00:00 - step 7 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 07:00:00 - step 8 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 08:00:00 - step 9 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 09:00:00 - step 10 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 10:00:00 - step 11 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 11:00:00 - step 12 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 12:00:00 - step 13 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 13:00:00 - step 14 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 14:00:00 - step 15 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 15:00:00 - step 16 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 16:00:00 - step 17 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 17:00:00 - step 18 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 18:00:00 - step 19 of 20 - 1000 active elements (0 deactivated)
17:19:51 INFO    opendrift:2035: 2015-11-16 19:00:00 - step 20 of 20 - 1000 active elements (0 deactivated)

<xarray.Dataset> Size: 2MB
Dimensions:                                   (trajectory: 1000, time: 21)
Coordinates:
  * trajectory                                (trajectory) int64 8kB 0 1 ... 999
  * time                                      (time) datetime64[ns] 168B 2015...
Data variables: (12/21)
    status                                    (trajectory, time) float32 84kB ...
    moving                                    (trajectory, time) float32 84kB ...
    age_seconds                               (trajectory, time) float32 84kB ...
    origin_marker                             (trajectory, time) float32 84kB ...
    lon                                       (trajectory, time) float32 84kB ...
    lat                                       (trajectory, time) float32 84kB ...
    ...                                        ...
    upward_sea_water_velocity                 (trajectory, time) float32 84kB ...
    sea_surface_wave_significant_height       (trajectory, time) float32 84kB ...
    sea_surface_wave_stokes_drift_x_velocity  (trajectory, time) float32 84kB ...
    sea_surface_wave_stokes_drift_y_velocity  (trajectory, time) float32 84kB ...
    sea_floor_depth_below_sea_level           (trajectory, time) float32 84kB ...
    land_binary_mask                          (trajectory, time) float32 84kB ...
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: 1000
  • time: 21
• Coordinates: (2)
  • trajectory
    (trajectory)
    int64
    0 1 2 3 4 5 ... 995 996 997 998 999

    cf_role :

    trajectory_id

    dtype :

    <class 'numpy.int32'>

    array([  0,   1,   2, ..., 997, 998, 999], shape=(1000,))

  • time
    (time)
    datetime64[ns]
    2015-11-16 ... 2015-11-16T20:00:00

    standard_name :

    time

    long_name :

    time

    dtype :

    <class 'numpy.float64'>

    array(['2015-11-16T00:00:00.000000000', '2015-11-16T01:00:00.000000000',
           '2015-11-16T02:00:00.000000000', '2015-11-16T03:00:00.000000000',
           '2015-11-16T04:00:00.000000000', '2015-11-16T05:00:00.000000000',
           '2015-11-16T06:00:00.000000000', '2015-11-16T07:00:00.000000000',
           '2015-11-16T08:00:00.000000000', '2015-11-16T09:00:00.000000000',
           '2015-11-16T10:00:00.000000000', '2015-11-16T11:00:00.000000000',
           '2015-11-16T12:00:00.000000000', '2015-11-16T13:00:00.000000000',
           '2015-11-16T14:00:00.000000000', '2015-11-16T15:00:00.000000000',
           '2015-11-16T16:00:00.000000000', '2015-11-16T17:00:00.000000000',
           '2015-11-16T18:00:00.000000000', '2015-11-16T19:00:00.000000000',
           '2015-11-16T20:00:00.000000000'], 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 1]

    flag_values :

    [0 1]

    flag_meanings :

    active stranded

    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=(1000, 21), 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 :

    0

    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=(1000, 21), dtype=float32)

  • age_seconds
    (trajectory, time)
    float32
    0.0 3.6e+03 ... 6.84e+04 7.2e+04

    dtype :

    <class 'numpy.float32'>

    units :

    s

    minval :

    0.0

    maxval :

    72000.0

    array([[    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           ...,
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.]],
          shape=(1000, 21), 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=(1000, 21), dtype=float32)

  • lon
    (trajectory, time)
    float32
    4.932 4.935 4.936 ... 4.934 4.94

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_east

    standard_name :

    longitude

    long_name :

    longitude

    axis :

    X

    minval :

    4.8018265

    maxval :

    5.025464

    array([[4.9316187, 4.935469 , 4.935703 , ..., 5.012147 , 5.009667 ,
            5.006866 ],
           [4.907173 , 4.9096217, 4.9081874, ..., 4.925963 , 4.914228 ,
            4.90007  ],
           [4.917538 , 4.918809 , 4.9167924, ..., 4.991405 , 4.9879136,
            4.984673 ],
           ...,
           [4.901688 , 4.9036655, 4.9018846, ..., 4.9183216, 4.9155717,
            4.9231205],
           [4.87944  , 4.8812313, 4.880254 , ..., 4.9236956, 4.9202743,
            4.9153028],
           [4.8935843, 4.894531 , 4.8925056, ..., 4.9295893, 4.9338517,
            4.9395537]], shape=(1000, 21), dtype=float32)

  • lat
    (trajectory, time)
    float32
    60.0 60.0 60.0 ... 60.23 60.24

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_north

    standard_name :

    latitude

    long_name :

    latitude

    axis :

    Y

    minval :

    59.971424

    maxval :

    60.36518

    array([[60.004986, 60.00307 , 60.000137, ..., 60.081593, 60.084927,
            60.091698],
           [60.00801 , 60.010117, 60.011894, ..., 60.158966, 60.1694  ,
            60.1841  ],
           [59.99621 , 59.996323, 59.99641 , ..., 60.098072, 60.098133,
            60.102467],
           ...,
           [60.001423, 60.004383, 60.00727 , ..., 60.19854 , 60.21608 ,
            60.23962 ],
           [59.98975 , 59.997166, 60.004936, ..., 60.23211 , 60.240887,
            60.251892],
           [59.98823 , 59.992466, 59.99713 , ..., 60.218357, 60.228626,
            60.241016]], shape=(1000, 21), 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=(1000, 21), 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=(1000, 21), 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=(1000, 21), 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=(1000, 21), dtype=float32)

  • x_sea_water_velocity
    (trajectory, time)
    float32
    0.05968 0.003619 ... 0.08774

    minval :

    -0.39344096

    maxval :

    0.33031613

    array([[ 0.059678  ,  0.00361914, -0.03596927, ..., -0.03833981,
            -0.04329464, -0.04329464],
           [ 0.03794021, -0.02222357, -0.04409198, ..., -0.1809599 ,
            -0.21822292, -0.21822292],
           [ 0.01970072, -0.03126333, -0.05821131, ..., -0.05395966,
            -0.05007378, -0.05007378],
           ...,
           [ 0.03064367, -0.02759623, -0.04713486, ..., -0.04234727,
             0.11616088,  0.11616088],
           [ 0.02777158, -0.01514912, -0.03243652, ..., -0.05264664,
            -0.07647216, -0.07647216],
           [ 0.01467744, -0.03139869, -0.04433347, ...,  0.06561133,
             0.0877376 ,  0.0877376 ]], shape=(1000, 21), dtype=float32)

  • y_sea_water_velocity
    (trajectory, time)
    float32
    -0.05928 -0.09072 ... 0.3834 0.3834

    minval :

    -0.20369317

    maxval :

    1.0186187

    array([[-0.05927943, -0.09071532, -0.09068023, ...,  0.10312719,
             0.20961687,  0.20961687],
           [ 0.06518719,  0.05498297,  0.04987679, ...,  0.3228862 ,
             0.45505264,  0.45505264],
           [ 0.00349597,  0.00281093,  0.01011937, ...,  0.001931  ,
             0.13408938,  0.13408938],
           ...,
           [ 0.09166781,  0.08936046,  0.09041139, ...,  0.5428132 ,
             0.7286283 ,  0.7286283 ],
           [ 0.22952697,  0.24044646,  0.24087498, ...,  0.2715891 ,
             0.34068108,  0.34068108],
           [ 0.13099697,  0.14444408,  0.15584973, ...,  0.3178421 ,
             0.38340795,  0.38340795]], shape=(1000, 21), dtype=float32)

  • sea_surface_height
    (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=(1000, 21), dtype=float32)

  • x_wind
    (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=(1000, 21), dtype=float32)

  • y_wind
    (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=(1000, 21), dtype=float32)

  • upward_sea_water_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=(1000, 21), dtype=float32)

  • sea_surface_wave_significant_height
    (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=(1000, 21), 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=(1000, 21), 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=(1000, 21), dtype=float32)

  • sea_floor_depth_below_sea_level
    (trajectory, time)
    float32
    1e+04 1e+04 1e+04 ... 1e+04 1e+04

    minval :

    10000.0

    maxval :

    10000.0

    array([[10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           ...,
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.]],
          shape=(1000, 21), 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=(1000, 21), dtype=float32)

• Indexes: (2)
  • trajectory
    PandasIndex

    PandasIndex(Index([  0,   1,   2,   3,   4,   5,   6,   7,   8,   9,
           ...
           990, 991, 992, 993, 994, 995, 996, 997, 998, 999],
          dtype='int64', name='trajectory', length=1000))

  • time
    PandasIndex

    PandasIndex(DatetimeIndex(['2015-11-16 00:00:00', '2015-11-16 01:00:00',
                   '2015-11-16 02:00:00', '2015-11-16 03:00:00',
                   '2015-11-16 04:00:00', '2015-11-16 05:00:00',
                   '2015-11-16 06:00:00', '2015-11-16 07:00:00',
                   '2015-11-16 08:00:00', '2015-11-16 09:00:00',
                   '2015-11-16 10:00:00', '2015-11-16 11:00:00',
                   '2015-11-16 12:00:00', '2015-11-16 13:00:00',
                   '2015-11-16 14:00:00', '2015-11-16 15:00:00',
                   '2015-11-16 16:00:00', '2015-11-16 17:00:00',
                   '2015-11-16 18:00:00', '2015-11-16 19:00:00',
                   '2015-11-16 20:00:00'],
                  dtype='datetime64[ns]', name='time', freq='h'))

• 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 2025-07-11 17:19:50.946460

  date_created :

  2025-07-11T17:19:50.946468

  source :

  Output from simulation with OpenDrift

  model_url :

  https://github.com/OpenDrift/opendrift

  opendrift_class :

  OceanDrift

  opendrift_module :

  opendrift.models.oceandrift

  readers :

  odict_keys(['/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc', 'global_landmask'])

  time_coverage_start :

  2015-11-16 00:00:00

  time_step_calculation :

  1:00:00

  time_step_output :

  1:00:00

  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 :

  None

  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 :

  1.14.2

  seed_geojson :

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

  simulation_time :

  2025-07-11 17:19:50.952316

  reader_x_sea_water_velocity :

  ['/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc']

  reader_y_sea_water_velocity :

  ['/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc']

  reader_sea_surface_height :

  0

  reader_x_wind :

  0

  reader_y_wind :

  0

  reader_upward_sea_water_velocity :

  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 :

  10000

  reader_land_binary_mask :

  ['global_landmask']

  time_coverage_end :

  2015-11-16 20:00:00

  time_coverage_duration :

  P0DT20H0M0S

  time_coverage_resolution :

  P0DT1H0M0S

  performance :

  -------------------- Reader performance: -------------------- /root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc 0:00:00.1 total 0:00:00.0 preparing 0:00:00.0 reading 0:00:00.0 interpolation 0:00:00.0 interpolation_time 0:00:00.0 rotating vectors 0:00:00.0 masking -------------------- global_landmask 0:00:01.4 total 0:00:00.0 preparing 0:00:01.4 reading 0:00:00.0 masking -------------------- Performance: 8.0 total time 4.4 configuration 0.0 preparing main loop 0.0 moving elements to ocean 2.0 main loop 0.0 updating elements 1.5 cleaning up --------------------

  geospatial_bounds_crs :

  EPSG:4326

  geospatial_bounds_vertical_crs :

  EPSG:5831

  geospatial_lat_min :

  59.971424

  geospatial_lat_max :

  60.36518

  geospatial_lat_units :

  degrees_north

  geospatial_lat_resolution :

  point

  geospatial_lon_min :

  4.8018265

  geospatial_lon_max :

  5.025464

  geospatial_lon_units :

  degrees_east

  geospatial_lon_resolution :

  point

  runtime :

  0:00:08.080644

  geospatial_vertical_min :

  0.0

  geospatial_vertical_max :

  0.0

  geospatial_vertical_positive :

  up

Store final field of x-component of current

original_current = reader_norkyst.var_block_after[list(reader_norkyst.var_block_after.keys())[0]].data_dict['x_sea_water_velocity'].copy()

For the second run, the NorKyst currents are convolved with a kernel, effectively lowering the spatial resolution. <reader>.set_convolution_kernel may also be given as an array (kernel) directly

N = 10  # Convolusion kernel size
reader_norkyst.set_convolution_kernel(N)  # Using convolution kernel for second run
o2 = OceanDrift(loglevel=20)
o2.add_reader([reader_norkyst])
o2.seed_elements(lon, lat, radius=1000, number=1000, time=time)
o2.run(steps=20)

17:19:54 INFO    opendrift:513: OpenDriftSimulation initialised (version 1.14.2 / v1.14.2-88-gf09b7bd)
17:19:54 INFO    opendrift.models.basemodel.environment:206: Adding a global landmask from GSHHG
17:19:54 INFO    opendrift.models.basemodel.environment:229: Fallback values will be used for the following variables which have no readers:
17:19:54 INFO    opendrift.models.basemodel.environment:232:    sea_surface_height: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    x_wind: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    y_wind: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    upward_sea_water_velocity: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    ocean_vertical_diffusivity: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    sea_surface_wave_significant_height: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    sea_surface_wave_stokes_drift_x_velocity: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    sea_surface_wave_stokes_drift_y_velocity: 0.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    ocean_mixed_layer_thickness: 50.000000
17:19:54 INFO    opendrift.models.basemodel.environment:232:    sea_floor_depth_below_sea_level: 10000.000000
17:19:54 INFO    opendrift:1732: Skipping environment variable ocean_vertical_diffusivity because of condition ['drift:vertical_mixing', 'is', False]
17:19:54 INFO    opendrift:1732: Skipping environment variable ocean_mixed_layer_thickness because of condition ['drift:vertical_mixing', 'is', False]
17:19:54 INFO    opendrift:1743: Storing previous values of element property lon because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
17:19:54 INFO    opendrift:1743: Storing previous values of element property lat because of condition (('general:coastline_action', 'in', ['stranding', 'previous']), 'or', ('general:seafloor_action', 'in', ['previous']))
17:19:54 INFO    opendrift:1751: Storing previous values of environment variable sea_surface_height because of condition ['drift:vertical_advection', 'is', True]
17:19:54 INFO    opendrift:899: Using existing reader for land_binary_mask
17:19:54 INFO    opendrift:928: All points are in ocean
17:19:54 INFO    opendrift:2035: 2015-11-16 00:00:00 - step 1 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 01:00:00 - step 2 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 02:00:00 - step 3 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 03:00:00 - step 4 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 04:00:00 - step 5 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 05:00:00 - step 6 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 06:00:00 - step 7 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 07:00:00 - step 8 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 08:00:00 - step 9 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 09:00:00 - step 10 of 20 - 1000 active elements (0 deactivated)
17:19:54 INFO    opendrift:2035: 2015-11-16 10:00:00 - step 11 of 20 - 1000 active elements (0 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 11:00:00 - step 12 of 20 - 1000 active elements (0 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 12:00:00 - step 13 of 20 - 1000 active elements (0 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 13:00:00 - step 14 of 20 - 1000 active elements (0 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 14:00:00 - step 15 of 20 - 1000 active elements (0 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 15:00:00 - step 16 of 20 - 1000 active elements (0 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 16:00:00 - step 17 of 20 - 999 active elements (1 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 17:00:00 - step 18 of 20 - 999 active elements (1 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 18:00:00 - step 19 of 20 - 999 active elements (1 deactivated)
17:19:55 INFO    opendrift:2035: 2015-11-16 19:00:00 - step 20 of 20 - 999 active elements (1 deactivated)

<xarray.Dataset> Size: 2MB
Dimensions:                                   (trajectory: 1000, time: 21)
Coordinates:
  * trajectory                                (trajectory) int64 8kB 0 1 ... 999
  * time                                      (time) datetime64[ns] 168B 2015...
Data variables: (12/21)
    status                                    (trajectory, time) float32 84kB ...
    moving                                    (trajectory, time) float32 84kB ...
    age_seconds                               (trajectory, time) float32 84kB ...
    origin_marker                             (trajectory, time) float32 84kB ...
    lon                                       (trajectory, time) float32 84kB ...
    lat                                       (trajectory, time) float32 84kB ...
    ...                                        ...
    upward_sea_water_velocity                 (trajectory, time) float32 84kB ...
    sea_surface_wave_significant_height       (trajectory, time) float32 84kB ...
    sea_surface_wave_stokes_drift_x_velocity  (trajectory, time) float32 84kB ...
    sea_surface_wave_stokes_drift_y_velocity  (trajectory, time) float32 84kB ...
    sea_floor_depth_below_sea_level           (trajectory, time) float32 84kB ...
    land_binary_mask                          (trajectory, time) float32 84kB ...
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: 1000
  • time: 21
• Coordinates: (2)
  • trajectory
    (trajectory)
    int64
    0 1 2 3 4 5 ... 995 996 997 998 999

    cf_role :

    trajectory_id

    dtype :

    <class 'numpy.int32'>

    array([  0,   1,   2, ..., 997, 998, 999], shape=(1000,))

  • time
    (time)
    datetime64[ns]
    2015-11-16 ... 2015-11-16T20:00:00

    standard_name :

    time

    long_name :

    time

    dtype :

    <class 'numpy.float64'>

    array(['2015-11-16T00:00:00.000000000', '2015-11-16T01:00:00.000000000',
           '2015-11-16T02:00:00.000000000', '2015-11-16T03:00:00.000000000',
           '2015-11-16T04:00:00.000000000', '2015-11-16T05:00:00.000000000',
           '2015-11-16T06:00:00.000000000', '2015-11-16T07:00:00.000000000',
           '2015-11-16T08:00:00.000000000', '2015-11-16T09:00:00.000000000',
           '2015-11-16T10:00:00.000000000', '2015-11-16T11:00:00.000000000',
           '2015-11-16T12:00:00.000000000', '2015-11-16T13:00:00.000000000',
           '2015-11-16T14:00:00.000000000', '2015-11-16T15:00:00.000000000',
           '2015-11-16T16:00:00.000000000', '2015-11-16T17:00:00.000000000',
           '2015-11-16T18:00:00.000000000', '2015-11-16T19:00:00.000000000',
           '2015-11-16T20:00:00.000000000'], 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 1]

    flag_values :

    [0 1]

    flag_meanings :

    active stranded

    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=(1000, 21), 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 :

    0

    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=(1000, 21), dtype=float32)

  • age_seconds
    (trajectory, time)
    float32
    0.0 3.6e+03 ... 6.84e+04 7.2e+04

    dtype :

    <class 'numpy.float32'>

    units :

    s

    minval :

    0.0

    maxval :

    72000.0

    array([[    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           ...,
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.],
           [    0.,  3600.,  7200., ..., 64800., 68400., 72000.]],
          shape=(1000, 21), 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=(1000, 21), dtype=float32)

  • lon
    (trajectory, time)
    float32
    4.932 4.935 4.933 ... 4.911 4.906

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_east

    standard_name :

    longitude

    long_name :

    longitude

    axis :

    X

    minval :

    4.834312

    maxval :

    5.0137777

    array([[4.9316187, 4.9346266, 4.9330306, ..., 4.9417024, 4.9355164,
            4.9281397],
           [4.907173 , 4.909293 , 4.907515 , ..., 4.9271955, 4.9196477,
            4.9145794],
           [4.917538 , 4.9199386, 4.9194775, ..., 4.9327583, 4.927513 ,
            4.9202185],
           ...,
           [4.901688 , 4.904373 , 4.9026804, ..., 4.9225664, 4.915075 ,
            4.9098125],
           [4.87944  , 4.882048 , 4.8818398, ..., 4.8980417, 4.891907 ,
            4.8849864],
           [4.8935843, 4.8956637, 4.894996 , ..., 4.919633 , 4.9114947,
            4.9057865]], shape=(1000, 21), dtype=float32)

  • lat
    (trajectory, time)
    float32
    60.0 60.01 60.02 ... 60.23 60.25

    dtype :

    <class 'numpy.float32'>

    units :

    degrees_north

    standard_name :

    latitude

    long_name :

    latitude

    axis :

    Y

    minval :

    59.97312

    maxval :

    60.36792

    array([[60.004986, 60.011307, 60.017315, ..., 60.200195, 60.21505 ,
            60.234215],
           [60.00801 , 60.013664, 60.018814, ..., 60.22448 , 60.23994 ,
            60.258842],
           [59.99621 , 60.002003, 60.0087  , ..., 60.204056, 60.218994,
            60.238216],
           ...,
           [60.001423, 60.007668, 60.013447, ..., 60.2245  , 60.23995 ,
            60.25901 ],
           [59.98975 , 59.997665, 60.005447, ..., 60.23732 , 60.25336 ,
            60.274147],
           [59.98823 , 59.994   , 60.00019 , ..., 60.21738 , 60.232998,
            60.25164 ]], shape=(1000, 21), 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=(1000, 21), 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=(1000, 21), 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=(1000, 21), 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=(1000, 21), dtype=float32)

  • x_sea_water_velocity
    (trajectory, time)
    float32
    0.0466 -0.02472 ... -0.0878 -0.0878

    minval :

    -0.21388566

    maxval :

    0.2938078

    array([[ 0.0466032 , -0.02471904, -0.05661011, ..., -0.09526091,
            -0.11353391, -0.11353391],
           [ 0.03284866, -0.02754405, -0.04655391, ..., -0.11614581,
            -0.07794284, -0.07794284],
           [ 0.03720125, -0.00714235, -0.05161379, ..., -0.08076245,
            -0.11225404, -0.11225404],
           ...,
           [ 0.04160668, -0.02622701, -0.05154842, ..., -0.11527719,
            -0.08092781, -0.08092781],
           [ 0.04042802, -0.00322479, -0.02251185, ..., -0.0943603 ,
            -0.1063821 , -0.1063821 ],
           [ 0.03223864, -0.01034477, -0.03131101, ..., -0.12525384,
            -0.08780408, -0.08780408]], shape=(1000, 21), dtype=float32)

  • y_sea_water_velocity
    (trajectory, time)
    float32
    0.1956 0.186 ... 0.5769 0.5769

    minval :

    0.026650101

    maxval :

    0.9059386

    array([[0.19560806, 0.18595685, 0.15426242, ..., 0.4596814 , 0.59311426,
            0.59311426],
           [0.17490537, 0.15946631, 0.13447344, ..., 0.478527  , 0.5849646 ,
            0.5849646 ],
           [0.17934851, 0.2073445 , 0.18000524, ..., 0.46229762, 0.5950058 ,
            0.5950058 ],
           ...,
           [0.19325654, 0.17887129, 0.15312281, ..., 0.47816265, 0.5899626 ,
            0.5899626 ],
           [0.2449153 , 0.24089564, 0.24292263, ..., 0.49649224, 0.64335006,
            0.64335006],
           [0.17847668, 0.19161771, 0.19111872, ..., 0.48333   , 0.576926  ,
            0.576926  ]], shape=(1000, 21), dtype=float32)

  • sea_surface_height
    (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=(1000, 21), dtype=float32)

  • x_wind
    (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=(1000, 21), dtype=float32)

  • y_wind
    (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=(1000, 21), dtype=float32)

  • upward_sea_water_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=(1000, 21), dtype=float32)

  • sea_surface_wave_significant_height
    (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=(1000, 21), 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=(1000, 21), 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=(1000, 21), dtype=float32)

  • sea_floor_depth_below_sea_level
    (trajectory, time)
    float32
    1e+04 1e+04 1e+04 ... 1e+04 1e+04

    minval :

    10000.0

    maxval :

    10000.0

    array([[10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           ...,
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.],
           [10000., 10000., 10000., ..., 10000., 10000., 10000.]],
          shape=(1000, 21), 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=(1000, 21), dtype=float32)

• Indexes: (2)
  • trajectory
    PandasIndex

    PandasIndex(Index([  0,   1,   2,   3,   4,   5,   6,   7,   8,   9,
           ...
           990, 991, 992, 993, 994, 995, 996, 997, 998, 999],
          dtype='int64', name='trajectory', length=1000))

  • time
    PandasIndex

    PandasIndex(DatetimeIndex(['2015-11-16 00:00:00', '2015-11-16 01:00:00',
                   '2015-11-16 02:00:00', '2015-11-16 03:00:00',
                   '2015-11-16 04:00:00', '2015-11-16 05:00:00',
                   '2015-11-16 06:00:00', '2015-11-16 07:00:00',
                   '2015-11-16 08:00:00', '2015-11-16 09:00:00',
                   '2015-11-16 10:00:00', '2015-11-16 11:00:00',
                   '2015-11-16 12:00:00', '2015-11-16 13:00:00',
                   '2015-11-16 14:00:00', '2015-11-16 15:00:00',
                   '2015-11-16 16:00:00', '2015-11-16 17:00:00',
                   '2015-11-16 18:00:00', '2015-11-16 19:00:00',
                   '2015-11-16 20:00:00'],
                  dtype='datetime64[ns]', name='time', freq='h'))

• 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 2025-07-11 17:19:54.683964

  date_created :

  2025-07-11T17:19:54.683974

  source :

  Output from simulation with OpenDrift

  model_url :

  https://github.com/OpenDrift/opendrift

  opendrift_class :

  OceanDrift

  opendrift_module :

  opendrift.models.oceandrift

  readers :

  odict_keys(['/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc', 'global_landmask'])

  time_coverage_start :

  2015-11-16 00:00:00

  time_step_calculation :

  1:00:00

  time_step_output :

  1:00:00

  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 :

  None

  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 :

  1.14.2

  seed_geojson :

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

  simulation_time :

  2025-07-11 17:19:54.688470

  reader_x_sea_water_velocity :

  ['/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc']

  reader_y_sea_water_velocity :

  ['/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc']

  reader_sea_surface_height :

  0

  reader_x_wind :

  0

  reader_y_wind :

  0

  reader_upward_sea_water_velocity :

  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 :

  10000

  reader_land_binary_mask :

  ['global_landmask']

  time_coverage_end :

  2015-11-16 20:00:00

  time_coverage_duration :

  P0DT20H0M0S

  time_coverage_resolution :

  P0DT1H0M0S

  performance :

  -------------------- Reader performance: -------------------- /root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc 0:00:00.2 total 0:00:00.0 preparing 0:00:00.1 reading 0:00:00.0 interpolation 0:00:00.0 interpolation_time 0:00:00.0 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: 0.6 total time 0.0 configuration 0.0 preparing main loop 0.0 moving elements to ocean 0.6 main loop 0.0 updating elements 0.0 cleaning up --------------------

  geospatial_bounds_crs :

  EPSG:4326

  geospatial_bounds_vertical_crs :

  EPSG:5831

  geospatial_lat_min :

  59.97312

  geospatial_lat_max :

  60.36792

  geospatial_lat_units :

  degrees_north

  geospatial_lat_resolution :

  point

  geospatial_lon_min :

  4.834312

  geospatial_lon_max :

  5.0137777

  geospatial_lon_units :

  degrees_east

  geospatial_lon_resolution :

  point

  runtime :

  0:00:00.643415

  geospatial_vertical_min :

  0.0

  geospatial_vertical_max :

  0.0

  geospatial_vertical_positive :

  up

Store final field of x-component of (convolved) current

convolved_current = reader_norkyst.var_block_after[
    "['x_sea_water_velocity', 'y_sea_water_velocity']"].data_dict['x_sea_water_velocity']

plt.subplot(2,1,1)
plt.imshow(original_current, interpolation='nearest')
plt.title('Original current field (x-component)')
clim = plt.gci().get_clim()
plt.colorbar()
plt.subplot(2,1,2)
plt.imshow(convolved_current, interpolation='nearest')
plt.clim(clim)  # Make sure plots are comparable
plt.colorbar()
plt.title('Final, convolved current field (x-component)')
plt.show()

Print and plot results, with convolved currents as background

print(o)
o.animation(compare=o2, fast=True, legend=[
    'Original currents', 'Current convoled with kernel of size %s' % N],
    background=['x_sea_water_velocity', 'y_sea_water_velocity'])

===========================
--------------------
Reader performance:
--------------------
/root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc
 0:00:00.2  total
 0:00:00.0  preparing
 0:00:00.1  reading
 0:00:00.0  interpolation
 0:00:00.0  interpolation_time
 0:00:00.0  rotating vectors
 0:00:00.0  masking
--------------------
global_landmask
 0:00:01.4  total
 0:00:00.0  preparing
 0:00:01.4  reading
 0:00:00.0  masking
--------------------
Performance:
    8.0 total time
    4.4 configuration
    0.0 preparing main loop
      0.0 moving elements to ocean
    2.0 main loop
      0.0 updating elements
    1.5 cleaning up
--------------------
===========================
Model:  OceanDrift     (OpenDrift version 1.14.2)
        938 active Lagrangian3DArray particles  (62 deactivated, 0 scheduled)
-------------------
Environment variables:
  -----
  x_sea_water_velocity
  y_sea_water_velocity
     1) /root/project/tests/test_data/16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc
  -----
  land_binary_mask
     1) global_landmask
  -----
Readers not added for the following variables:
  sea_floor_depth_below_sea_level
  sea_surface_height
  sea_surface_wave_significant_height
  sea_surface_wave_stokes_drift_x_velocity
  sea_surface_wave_stokes_drift_y_velocity
  upward_sea_water_velocity
  x_wind
  y_wind

Discarded readers:

Time:
        Start: 2015-11-16 00:00:00 UTC
        Present: 2015-11-16 20:00:00 UTC
        Calculation steps: 20 * 1:00:00 - total time: 20:00:00
        Output steps: 21 * 1:00:00
===========================

17:19:55 WARNING opendrift:2391: Plotting fast. This will make your plots less accurate.
17:20:10 INFO    opendrift:4553: Saving animation to /root/project/docs/source/gallery/animations/example_convolve_input_0.gif...
17:21:46 INFO    opendrift:2994: Time to make animation: 0:01:51.283350

o.plot(fast=True)

17:21:46 WARNING opendrift:2391: Plotting fast. This will make your plots less accurate.

(<GeoAxes: title={'center': 'OpenDrift - OceanDrift\n2015-11-16 00:00 to 2015-11-16 20:00 UTC (21 steps)'}>, <Figure size 705.673x1100 with 1 Axes>)