Compare March 14, 2016 currents with OceanViewer
In [1]:
import netCDF4 as nc
import matplotlib.pyplot as plt
import numpy as np
import pytz
from salishsea_tools import tidetools, viz_tools, nc_tools
from nowcast import research_VENUS
%matplotlib inline
In [2]:
ts=0
fU = nc.Dataset('/results/SalishSea/nowcast/14mar16/SalishSea_1h_20160314_20160314_grid_U.nc')
u = fU.variables['vozocrtx'][ts,0,:,:]
fV = nc.Dataset('/results/SalishSea/nowcast/14mar16/SalishSea_1h_20160314_20160314_grid_V.nc')
v = fV.variables['vomecrty'][ts,0,:,:]
t = nc_tools.timestamp(fU,ts)
print(t.to('US/Pacific'))
2016-03-13T17:30:00-07:00
Weird. Oceanviewer is reading the first time as 18:30 PDT - but I think 17:30 PDT or 16:30 PST are correct.
00:30 UTC should be -8 hours to PST which is 4:30pm which is 16:30
Maybe the first time in Oceanviewer isn't t=0 on the NEMO file or I am totally confused about timezones?
Better trust the time reported on OceanViewer and compare 1830 PDT
In [3]:
ts=1
fU = nc.Dataset('/results/SalishSea/nowcast/14mar16/SalishSea_1h_20160314_20160314_grid_U.nc')
u = fU.variables['vozocrtx'][ts,0,:,:]
fV = nc.Dataset('/results/SalishSea/nowcast/14mar16/SalishSea_1h_20160314_20160314_grid_V.nc')
v = fV.variables['vomecrty'][ts,0,:,:]
t = nc_tools.timestamp(fU,ts)
print(t.to('US/Pacific'))
2016-03-13T18:30:00-07:00
In [4]:
grid_B = nc.Dataset('/data/nsoontie/MEOPAR/NEMO-forcing/grid/bathy_meter_SalishSea2.nc')
bathy, X, Y = tidetools.get_bathy_data(grid_B)
Xs=X[1:,1:]
Ys=Y[1:,1:]
mesh_mask = nc.Dataset('/data/nsoontie/MEOPAR/NEMO-forcing/grid/mesh_mask_SalishSea2.nc')
umask = 1- mesh_mask.variables['umask'][0,0,:,:]
vmask = 1- mesh_mask.variables['vmask'][0,0,:,:]
In [5]:
um = np.ma.array(u,mask=umask)
vm = np.ma.array(v,mask=vmask)
urot, vrot = research_VENUS.unstag_rot(um,vm)
uunstag, vunstag = viz_tools.unstagger(um, vm)
Rotated
In [6]:
fig,ax = plt.subplots(1,1,figsize=(10,10))
st=10
ax.quiver(Xs[::st,::st],Ys[::st,::st],urot[::st,::st],vrot[::st,::st])
viz_tools.plot_coastline(ax,grid_B,coords='map')
Out[6]:
<matplotlib.contour.QuadContourSet at 0x7fe80d459f98>
Not Rotated
In [7]:
fig,ax = plt.subplots(1,1,figsize=(10,10))
st=10
ax.quiver(Xs[::st,::st],Ys[::st,::st],uunstag[::st,::st],vunstag[::st,::st])
viz_tools.plot_coastline(ax,grid_B,coords='map')
Out[7]:
<matplotlib.contour.QuadContourSet at 0x7fe80d470c88>
The Not Rotated plot looks like Oceanviewer
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