Source code for mpas_tools.ocean.depth

import xarray
import numpy
import argparse
import sys
from datetime import datetime
import netCDF4

from mpas_tools.io import write_netcdf


[docs]def compute_depth(refBottomDepth): """ Computes depth and depth bounds given refBottomDepth Parameters ---------- refBottomDepth : xarray.DataArray the depth of the bottom of each vertical layer in the initial state (perfect z-level coordinate) Returns ------- depth : numpy.ndarray the vertical coordinate defining the middle of each layer depth_bnds : numpy.ndarray the vertical coordinate defining the top and bottom of each layer """ # Authors # ------- # Xylar Asay-Davis refBottomDepth = refBottomDepth.values depth_bnds = numpy.zeros((len(refBottomDepth), 2)) depth_bnds[0, 0] = 0. depth_bnds[1:, 0] = refBottomDepth[0:-1] depth_bnds[:, 1] = refBottomDepth depth = 0.5*(depth_bnds[:, 0] + depth_bnds[:, 1]) return depth, depth_bnds
[docs]def compute_zmid(bottomDepth, maxLevelCell, layerThickness, depth_dim='nVertLevels'): """ Computes zMid given data arrays for bottomDepth, maxLevelCell and layerThickness Parameters ---------- bottomDepth : xarray.DataArray the depth of the ocean bottom (positive) maxLevelCell : xarray.DataArray the 1-based vertical index of the bottom of the ocean layerThickness : xarray.DataArray the thickness of MPAS-Ocean layers (possibly as a function of time) depth_dim : str, optional the name of the vertical dimension Returns ------- zMid : xarray.DataArray the vertical coordinate defining the middle of each layer, masked below the bathymetry """ # Authors # ------- # Xylar Asay-Davis nDepth = layerThickness.sizes[depth_dim] vertIndex = \ xarray.DataArray.from_dict({'dims': (depth_dim,), 'data': numpy.arange(nDepth)}) layerThickness = layerThickness.where(vertIndex < maxLevelCell) thicknessSum = layerThickness.sum(dim=depth_dim) thicknessCumSum = layerThickness.cumsum(dim=depth_dim) zSurface = -bottomDepth+thicknessSum zLayerBot = zSurface - thicknessCumSum zMid = zLayerBot + 0.5*layerThickness zMid = zMid.where(vertIndex < maxLevelCell) zMid = zMid.transpose('Time', 'nCells', depth_dim) return zMid
[docs]def add_depth(inFileName, outFileName, coordFileName=None): """ Add a 1D depth coordinate to an MPAS-Ocean file. Parameters ---------- inFileName : str An input MPAS-Ocean file that depth should be added to, used for coords if another file is not provided via ``coordFileName``. outFileName : str An output MPAS-Ocean file with depth added coordFileName : str, optional An MPAS-Ocean file with ``refBottomDepth`` """ if coordFileName is not None: coordFileName = inFileName ds = xarray.open_dataset(inFileName, mask_and_scale=False) if 'nVertLevels' in ds.dims: ds = ds.rename({'nVertLevels': 'depth'}) dsCoord = xarray.open_dataset(coordFileName, mask_and_scale=False) dsCoord = dsCoord.rename({'nVertLevels': 'depth'}) depth, depth_bnds = compute_depth(dsCoord.refBottomDepth) ds.coords['depth'] = ('depth', depth) ds.depth.attrs['long_name'] = 'reference depth of the center of ' \ 'each vertical level' ds.depth.attrs['standard_name'] = 'depth' ds.depth.attrs['units'] = 'meters' ds.depth.attrs['axis'] = 'Z' ds.depth.attrs['positive'] = 'down' ds.depth.attrs['valid_min'] = depth_bnds[0, 0] ds.depth.attrs['valid_max'] = depth_bnds[-1, 1] ds.depth.attrs['bounds'] = 'depth_bnds' ds.coords['depth_bnds'] = (('depth', 'nbnd'), depth_bnds) ds.depth_bnds.attrs['long_name'] = 'Gridcell depth interfaces' for varName in ds.data_vars: var = ds[varName] if 'depth' in var.dims: var = var.assign_coords(depth=ds.depth) ds[varName] = var time = datetime.now().strftime('%c') history = '{}: {}'.format(time, ' '.join(sys.argv)) if 'history' in ds.attrs: ds.attrs['history'] = '{}\n{}'.format(history, ds.attrs['history']) else: ds.attrs['history'] = history write_netcdf(ds, outFileName)
def main_add_depth(): parser = argparse.ArgumentParser( formatter_class=argparse.RawTextHelpFormatter) parser.add_argument("-c", "--coordFileName", dest="coordFileName", type=str, required=False, help="An MPAS-Ocean file with refBottomDepth") parser.add_argument("-i", "--inFileName", dest="inFileName", type=str, required=True, help="An input MPAS-Ocean file that depth should be" "added to, used for coords if another file is" "not provided via -c.") parser.add_argument("-o", "--outFileName", dest="outFileName", type=str, required=True, help="An output MPAS-Ocean file with depth added") args = parser.parse_args() add_depth(args.inFileName, args.outFileName, coordFileName=args.coordFileName)
[docs]def add_zmid(inFileName, outFileName, coordFileName=None): """ Add a 3D, time-independent depth coordinate to an MPAS-Ocean file. Parameters ---------- inFileName : str An input MPAS-Ocean file that ``zMid`` should be added to, used for coords if another file is not provided via ``coordFileName``. outFileName : str An output MPAS-Ocean file with ``zMid`` added coordFileName : str, optional An MPAS-Ocean file with ``bottomDepth``, ``maxLevelCell`` and ``layerThickness`` but not ``zMid`` """ if coordFileName is None: coordFileName = inFileName ds = xarray.open_dataset(inFileName, mask_and_scale=False) if 'nVertLevels' in ds.dims: ds = ds.rename({'nVertLevels': 'depth'}) # dsCoord doesn't have masking disabled because we want it for zMid dsCoord = xarray.open_dataset(coordFileName) dsCoord = dsCoord.rename({'nVertLevels': 'depth'}) ds.coords['zMid'] = compute_zmid(dsCoord.bottomDepth, dsCoord.maxLevelCell, dsCoord.layerThickness, depth_dim='depth') fillValue = netCDF4.default_fillvals['f8'] ds.coords['zMid'] = ds.zMid.where(ds.zMid.notnull(), other=fillValue) ds.zMid.attrs['units'] = 'meters' ds.zMid.attrs['positive'] = 'up' ds.zMid.attrs['_FillValue'] = fillValue for varName in ds.data_vars: var = ds[varName] if 'nCells' in var.dims and 'depth' in var.dims: var = var.assign_coords(zMid=ds.zMid) ds[varName] = var time = datetime.now().strftime('%c') history = '{}: {}'.format(time, ' '.join(sys.argv)) if 'history' in ds.attrs: ds.attrs['history'] = '{}\n{}'.format(history, ds.attrs['history']) else: ds.attrs['history'] = history write_netcdf(ds, outFileName)
def main_add_zmid(): parser = argparse.ArgumentParser( formatter_class=argparse.RawTextHelpFormatter) parser.add_argument("-c", "--coordFileName", dest="coordFileName", type=str, required=False, help="An MPAS-Ocean file with bottomDepth, maxLevelCell" "and layerThickness but not zMid") parser.add_argument("-i", "--inFileName", dest="inFileName", type=str, required=True, help="An input MPAS-Ocean file that zMid should be" "added to, used for coords if another file is" "not provided via -c.") parser.add_argument("-o", "--outFileName", dest="outFileName", type=str, required=True, help="An output MPAS-Ocean file with zMid added") args = parser.parse_args() add_zmid(args.inFileName, args.outFileName, coordFileName=args.coordFileName)
[docs]def write_time_varying_zmid(inFileName, outFileName, coordFileName=None, prefix=None): """ Add a 3D, time-independent depth coordinate to an MPAS-Ocean file. Parameters ---------- inFileName : str An input MPAS-Ocean file with some form of ``layerThickness``, and also ``bottomDepth`` and ``maxLevelCell`` if no ``coordFileName`` is provided. outFileName : str An output MPAS-Ocean file with ``zMid`` for each time in the input file coordFileName : str, optional An MPAS-Ocean file with ``bottomDepth`` and ``maxLevelCell`` prefix : str, optional A prefix on ``layerThickness`` (in) and ``zMid`` (out), such as ``timeMonthly_avg_`` """ if coordFileName is None: coordFileName = inFileName dsCoord = xarray.open_dataset(coordFileName) dsCoord = dsCoord.rename({'nVertLevels': 'depth'}) dsIn = xarray.open_dataset(inFileName) dsIn = dsIn.rename({'nVertLevels': 'depth'}) inVarName = '{}layerThickness'.format(prefix) outVarName = '{}zMid'.format(prefix) layerThickness = dsIn[inVarName] zMid = compute_zmid(dsCoord.bottomDepth, dsCoord.maxLevelCell, layerThickness, depth_dim='depth') dsOut = xarray.Dataset() dsOut[outVarName] = zMid fillValue = netCDF4.default_fillvals['f8'] dsOut[outVarName] = dsOut[outVarName].where(dsOut[outVarName].notnull(), other=fillValue) dsOut[outVarName].attrs['units'] = 'meters' dsOut[outVarName].attrs['positive'] = 'up' dsOut[outVarName].attrs['_FillValue'] = fillValue time = datetime.now().strftime('%c') history = '{}: {}'.format(time, ' '.join(sys.argv)) dsOut.attrs['history'] = history write_netcdf(dsOut, outFileName)
def main_write_time_varying_zmid(): parser = argparse.ArgumentParser( formatter_class=argparse.RawTextHelpFormatter) parser.add_argument("-c", "--coordFileName", dest="coordFileName", type=str, required=False, help="An MPAS-Ocean file with bottomDepth and " "maxLevelCell") parser.add_argument("-i", "--inFileName", dest="inFileName", type=str, required=True, help="An input MPAS-Ocean file with some form of" "layerThickness, and also bottomDepth and" "maxLevelCell if no coordinate file is provided.") parser.add_argument("-o", "--outFileName", dest="outFileName", type=str, required=True, help="An output MPAS-Ocean file with zMid for each" "time in the input file") parser.add_argument("-p", "--prefix", dest="prefix", type=str, required=False, default="", help="A prefix on layerThickness (in) and zMid (out)," "such as 'timeMonthly_avg_'") args = parser.parse_args() write_time_varying_zmid( args.inFileName, args.outFileName, coordFileName=args.coordFileName, prefix=args.prefix)