#%%
# Note that Runge-Kutta here makes a difference to Euler scheme
o.set_config('drift:advection_scheme', 'runge-kutta4')
o.disable_vertical_motion()
o.set_config('environment:fallback:land_binary_mask', 0)
double_gyre = reader_double_gyre.Reader(epsilon=.25, omega=0.628, A=0.1)
print(double_gyre)
o.add_reader(double_gyre)
#%%
# Calculate Lyapunov exponents
times = [double_gyre.initial_time +
n*time_step_output for n in range(steps)]
lcs = o.calculate_ftle(time=times, time_step=time_step,
duration=duration, delta=delta, RLCS=False)
#%%
# Make run with particles for the same period
o.reset()
x = [.9]
y = [.5]
lon, lat = double_gyre.xy2lonlat(x, y)
o.seed_elements(lon, lat, radius=.15, number=2000,
time=double_gyre.initial_time)
o.disable_vertical_motion()
o.run(duration=duration, time_step=time_step,
time_step_output=time_step_output)
o.animation(buffer=0, lcs=lcs, hide_landmask=True)
from opendrift.readers import reader_double_gyre
from opendrift.models.oceandrift import OceanDrift
o = OceanDrift(loglevel=20) # Set loglevel to 0 for debug information
o.fallback_values['land_binary_mask'] = 0
# Note that Runge-Kutta here makes a difference to Euler scheme
o.set_config('drift:scheme', 'runge-kutta4')
double_gyre = reader_double_gyre.Reader(epsilon=.25, omega=0.628, A=0.1)
print double_gyre
o.add_reader(double_gyre)
lcs = o.calculate_ftle(time=double_gyre.initial_time + timedelta(seconds=3),
time_step=timedelta(seconds=.5),
duration=timedelta(seconds=15),
delta=.02)
# These plots should reproduce Mov 12 on this page:
# http://shaddenlab.berkeley.edu/uploads/LCS-tutorial/examples.html
plt.subplot(2, 1, 1)
plt.imshow(lcs['RLCS'][0, :, :],
interpolation='nearest',
cmap='jet',
origin='lower')
plt.colorbar()
plt.title('Repelling LCS (forwards)')
plt.subplot(2, 1, 2)
plt.imshow(lcs['ALCS'][0, :, :],
interpolation='nearest',
cmap='jet',
o = OceanDrift(loglevel=20) # Set loglevel to 0 for debug information
o.set_config('general:basemap_resolution', 'i')
# Norkyst ocean model
reader_norkyst = reader_netCDF_CF_generic.Reader(
o.test_data_folder() +
'16Nov2015_NorKyst_z_surface/norkyst800_subset_16Nov2015.nc')
#o.add_reader([reader_norkyst, reader_arome])
o.add_reader([reader_norkyst])
# Calculating attracting/backwards FTLE/LCS at 20 hours
lcs = o.calculate_ftle(time=reader_norkyst.start_time + timedelta(hours=20),
time_step=timedelta(minutes=30),
duration=timedelta(hours=5),
delta=1000,
RLCS=False)
# Simulation from beginning and up to 30 hours (time of LCS)
o.reset()
o.seed_elements(lon=4.4,
lat=60.2,
number=1000,
radius=1000,
time=reader_norkyst.start_time)
o.run(end_time=reader_norkyst.start_time + timedelta(hours=20),
time_step=timedelta(minutes=30))
o.plot(lcs=lcs, vmin=1e-7, vmax=1e-4, colorbar=True, show_particles=True)
