Source code for satpy.readers.mimic_TPW2_nc

#!/usr/bin/env python
# -*- coding: utf-8 -*-
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"""Reader for Mimic TPW data in netCDF format from SSEC.

This module implements reader for MIMIC_TPW2 netcdf files.
MIMIC-TPW2 is an experimental global product of total precipitable water (TPW),
using morphological compositing of the MIRS retrieval from several available
operational microwave-frequency sensors. Originally described in a 2010 paper by
Wimmers and Velden. This Version 2 is developed from an older method that uses simpler,
but more limited TPW retrievals and advection calculations.

More information, data and credits at
http://tropic.ssec.wisc.edu/real-time/mtpw2/credits.html
"""

import logging

import numpy as np
import xarray as xr
from pyresample.geometry import AreaDefinition

from satpy.readers.netcdf_utils import NetCDF4FileHandler, netCDF4

logger = logging.getLogger(__name__)


[docs] class MimicTPW2FileHandler(NetCDF4FileHandler): """NetCDF4 reader for MIMC TPW.""" def __init__(self, filename, filename_info, filetype_info): """Initialize the reader.""" super(MimicTPW2FileHandler, self).__init__(filename, filename_info, filetype_info, xarray_kwargs={"decode_times": False})
[docs] def available_datasets(self, configured_datasets=None): """Get datasets in file matching gelocation shape (lat/lon).""" lat_shape = self.file_content.get('/dimension/lat') lon_shape = self.file_content.get('/dimension/lon') # Read the lat/lon variables? handled_variables = set() # update previously configured datasets logger.debug("Starting previously configured variables loop...") for is_avail, ds_info in (configured_datasets or []): # some other file handler knows how to load this if is_avail is not None: yield is_avail, ds_info var_name = ds_info.get('file_key', ds_info['name']) # logger.debug("Evaluating previously configured variable: %s", var_name) matches = self.file_type_matches(ds_info['file_type']) # we can confidently say that we can provide this dataset and can # provide more info if matches and var_name in self: logger.debug("Handling previously configured variable: %s", var_name) handled_variables.add(var_name) new_info = ds_info.copy() # don't mess up the above yielded yield True, new_info elif is_avail is None: # if we didn't know how to handle this dataset and no one else did # then we should keep it going down the chain yield is_avail, ds_info # Iterate over dataset contents for var_name, val in self.file_content.items(): # Only evaluate variables if isinstance(val, netCDF4.Variable): logger.debug("Evaluating new variable: %s", var_name) var_shape = self[var_name + "/shape"] logger.debug("Dims:{}".format(var_shape)) if var_shape == (lat_shape, lon_shape): logger.debug("Found valid additional dataset: %s", var_name) # Skip anything we have already configured if var_name in handled_variables: logger.debug("Already handled, skipping: %s", var_name) continue handled_variables.add(var_name) # Create new ds_info object new_info = { 'name': var_name, 'file_key': var_name, 'file_type': self.filetype_info['file_type'], } logger.debug(var_name) yield True, new_info
[docs] def get_dataset(self, ds_id, info): """Load dataset designated by the given key from file.""" logger.debug("Getting data for: %s", ds_id['name']) file_key = info.get('file_key', ds_id['name']) data = np.flipud(self[file_key]) data = xr.DataArray(data, dims=['y', 'x']) data.attrs = self.get_metadata(data, info) if 'lon' in data.dims: data.rename({'lon': 'x'}) if 'lat' in data.dims: data.rename({'lat': 'y'}) return data
[docs] def get_area_def(self, dsid): """Flip data up/down and define equirectangular AreaDefintion.""" flip_lat = np.flipud(self['latArr']) latlon = np.meshgrid(self['lonArr'], flip_lat) width = self['lonArr/shape'][0] height = self['latArr/shape'][0] lower_left_x = latlon[0][height-1][0] lower_left_y = latlon[1][height-1][0] upper_right_y = latlon[1][0][width-1] upper_right_x = latlon[0][0][width-1] area_extent = (lower_left_x, lower_left_y, upper_right_x, upper_right_y) description = "MIMIC TPW WGS84" area_id = 'mimic' proj_id = 'World Geodetic System 1984' projection = 'EPSG:4326' area_def = AreaDefinition(area_id, description, proj_id, projection, width, height, area_extent, ) return area_def
[docs] def get_metadata(self, data, info): """Get general metadata for file.""" metadata = {} metadata.update(data.attrs) metadata.update(info) metadata.update({ 'platform_shortname': 'aggregated microwave', 'sensor': 'mimic', 'start_time': self.start_time, 'end_time': self.end_time, }) metadata.update(self[info.get('file_key')].variable.attrs) return metadata
@property def start_time(self): """Start timestamp of the dataset determined from yaml.""" return self.filename_info['start_time'] @property def end_time(self): """End timestamp of the dataset same as start_time.""" return self.filename_info.get('end_time', self.start_time) @property def sensor_name(self): """Sensor name.""" return self["sensor"]