def test_fraction_on_land(self):
"""Test _fraction_on_land helper function."""
res_deg = 10 / (60 * 60)
bounds = (-149.54, -23.42, -149.40, -23.33)
lat = np.arange(bounds[1] + 0.5 * res_deg, bounds[3], res_deg)
lon = np.arange(bounds[0] + 0.5 * res_deg, bounds[2], res_deg)
shape = (lat.size, lon.size)
lon, lat = [ar.ravel() for ar in np.meshgrid(lon, lat)]
centroids = Centroids()
centroids.set_lat_lon(lat, lon)
centroids.set_dist_coast(signed=True, precomputed=True)
dem_bounds = (bounds[0] - 1, bounds[1] - 1, bounds[2] + 1, bounds[3] + 1)
dem_res = 3 / (60 * 60)
with tmp_artifical_topo(dem_bounds, dem_res) as topo_path:
fraction = _fraction_on_land(centroids, topo_path)
fraction = fraction.reshape(shape)
dist_coast = centroids.dist_coast.reshape(shape)
# check valid range and order of magnitude
self.assertTrue(np.all((fraction >= 0) & (fraction <= 1)))
np.testing.assert_array_equal(fraction[dist_coast > 1000], 0)
np.testing.assert_array_equal(fraction[dist_coast < -1000], 1)
# check individual known pixel values
self.assertAlmostEqual(fraction[24, 10], 0.0)
self.assertAlmostEqual(fraction[22, 11], 0.21)
self.assertAlmostEqual(fraction[22, 12], 0.93)
self.assertAlmostEqual(fraction[21, 14], 1.0)
def __init__(self, bounds, res_deg):
"""Read distance to coast values from raster file for later use.
Parameters
----------
bounds : tuple (lon_min, lat_min, lon_max, lat_max)
Coordinates of bounding box
res_deg : float
Resolution in degrees
"""
lat = np.arange(bounds[3] - 0.5 * res_deg, bounds[1], -res_deg)
lon = np.arange(bounds[0] + 0.5 * res_deg, bounds[2], res_deg)
self.shape = (lat.size, lon.size)
self.transform = rasterio.Affine(res_deg, 0, bounds[0], 0, -res_deg, bounds[3])
centroids = Centroids()
centroids.set_lat_lon(*[ar.ravel() for ar in np.meshgrid(lon, lat)][::-1])
centroids.set_dist_coast(signed=True, precomputed=True)
self.dist_coast = centroids.dist_coast
def test_surge_from_track(self):
"""Test TCSurgeBathtub.from_tc_winds function."""
# similar to IBTrACS 2010029S12177 (OLI, 2010) hitting Tubuai, but much stronger
track = xr.Dataset({
'radius_max_wind': ('time', [15., 15, 15, 15, 15, 17, 20, 20]),
'radius_oci': ('time', [202., 202, 202, 202, 202, 202, 202, 202]),
'max_sustained_wind': ('time', [155., 147, 140, 135, 130, 122, 115, 116]),
'central_pressure': ('time', [894., 901, 906, 909, 913, 918, 924, 925]),
'environmental_pressure': ('time', np.full((8,), 1004.0, dtype=np.float64)),
'time_step': ('time', np.full((8,), 3.0, dtype=np.float64)),
}, coords={
'time': np.arange('2010-02-05T09:00', '2010-02-06T09:00',
np.timedelta64(3, 'h'), dtype='datetime64[h]'),
'lat': ('time', [-24.33, -25.54, -24.79, -24.05,
-23.35, -22.7, -22.07, -21.50]),
'lon': ('time', [-147.27, -148.0, -148.51, -148.95,
-149.41, -149.85, -150.27, -150.56]),
}, attrs={
'max_sustained_wind_unit': 'kn',
'central_pressure_unit': 'mb',
'name': 'test',
'sid': '2010029S12177_test',
'orig_event_flag': True,
'data_provider': 'unit_test',
'basin': 'SP',
'id_no': 0,
'category': 4,
})
tc_track = TCTracks()
tc_track.data = [track]
tc_track.equal_timestep(time_step_h=1)
res_deg = 10 / (60 * 60)
bounds = (-149.54, -23.42, -149.40, -23.33)
lat = np.arange(bounds[1] + 0.5 * res_deg, bounds[3], res_deg)
lon = np.arange(bounds[0] + 0.5 * res_deg, bounds[2], res_deg)
shape = (lat.size, lon.size)
lon, lat = [ar.ravel() for ar in np.meshgrid(lon, lat)]
centroids = Centroids()
centroids.set_lat_lon(lat, lon)
centroids.set_dist_coast(signed=True, precomputed=True)
wind_haz = TropCyclone()
wind_haz.set_from_tracks(tc_track, centroids=centroids)
dem_bounds = (bounds[0] - 1, bounds[1] - 1, bounds[2] + 1, bounds[3] + 1)
dem_res = 3 / (60 * 60)
with tmp_artifical_topo(dem_bounds, dem_res) as topo_path:
for slr in [0, 0.5, 1.5]:
surge_haz = TCSurgeBathtub.from_tc_winds(wind_haz, topo_path,
add_sea_level_rise=slr)
inten = surge_haz.intensity.toarray().reshape(shape)
fraction = surge_haz.fraction.toarray().reshape(shape)
# check valid range and order of magnitude
np.testing.assert_array_equal(inten >= 0, True)
np.testing.assert_array_equal(inten <= 10, True)
np.testing.assert_array_equal((fraction >= 0) & (fraction <= 1), True)
np.testing.assert_array_equal(inten[fraction == 0], 0)
# check individual known pixel values
self.assertAlmostEqual(inten[9, 31], max(-0.391 + slr, 0), places=2)
self.assertAlmostEqual(inten[14, 34] - slr, 3.637, places=2)