pybob.ICESat

pybob.ICESat provides an interface to extracted ICESat(-1) data stored in HDF5 format. Pre-extracted ICESat tracks for

each of the RGI subregions can be found here.

class pybob.ICESat.ICESat(in_filename, in_dir=None, cols=['lat', 'lon', 'd_elev', 'd_UTCTime'], ellipse_hts=True)

Create an ICESat dataset from an HDF5 file containing ICESat data.

__init__(in_filename, in_dir=None, cols=['lat', 'lon', 'd_elev', 'd_UTCTime'], ellipse_hts=True)

Parameters:

• in_filename (str) – Filename (optionally with path) of HDF5 file to be read in.
• in_dir (str) – Directory where in_filename is located. If not given, the directory will be determined from the input filename.
• cols (array-like) – Columns to read in and set as attributes in the ICESat object. Default values are [‘lat’, ‘lon’, ‘d_elev’, ‘d_UTCTime’], and will be added if not specified.
• ellipse_hts (bool) – Convert elevations to ellipsoid heights. Default is True.

The following example:

>>> ICESat('donjek_icesat.h5', ellipse_hts=True)

will return an ICESat object with lat, lon, elevation, and UTCTime attributes, with elevations given as height above WGS84 ellipsoid.

clean(el_limit=-500)

Remove all elevation points below a given elevation.

Parameters:el_limit (float) – minimum elevation to accept

clip(bounds)

Remove ICEsat data that falls outside of a given bounding box.

Parameters:bounds (array-like) – bounding box to clip to, given as xmin, xmax, ymin, ymax

display(fig=None, extent=None, sfact=1, showfig=True, geo=False, **kwargs)

Plot ICESat tracks in a figure.

Parameters:

• fig (matplotlib.figure.Figure) – Figure to plot tracks in. If not set, creates a new figure.
• extent (array-like) – Spatial extent to limit the figure to, given as xmin, xmax, ymin, ymax.
• sfact (int) – Factor by which to reduce the number of points plotted. Default is 1 (i.e., all points are plotted).
• showfig (bool) – Open the figure window. Default is True.
• geo (bool) – Plot tracks in lat/lon coordinates, rather than projected coordinates. Default is False.
• kwargs – Optional keyword arguments to pass to matplotlib.pyplot.plot

Returns fig:

Handle pointing to the matplotlib Figure created (or passed to display).

from_ellipse()

Convert ICESat elevations from ellipsoid heights, based on the data stored in the HDF5 file.

get_bounds(geo=False)

Return bounding coordinates of the dataset.

Parameters:geo (bool) – Return geographic (lat/lon) coordinates (default is False) Returns bounds:xmin, xmax, ymin, ymax values of dataset.

Example: >>> xmin, xmax, ymin, ymax = my_icesat.get_bounds()

mask(mask, mask_value=True, drop=False)

Mask values

Parameters:

• mask (array-like) – Array of same size as self.img corresponding to values that should be masked.
• mask_value (bool or numeric) – Value within mask to mask. If True, masks image where mask is True. If numeric, masks image where mask == mask_value.
• drop (bool) – remove values from dataset (True), or mask using numpy.masked_array (False). Default is False.

project(dest_proj)

Project the ICESat dataset to a given coordinate system, using pyproj.transform. ICESat.project does not overwrite the lat/lon coordinates, so calling ICESat.project will only update self.x,self.y for the dataset, self.xy, and self.proj.

Parameters:dest_proj (str or pyproj.Proj) – Coordinate system to project the dataset into. If dest_proj is a string, ICESat.project() will create a pyproj.Proj instance with it.

Example: Project icesat_data to Alaska Albers (NAD83) using epsg code:

>>> icesat_data.project('epsg:3338')

to_csv(out_filename)

Write ICESat data to csv format using pandas.

Parameters:out_filename (str) – Filename (optionally with path) of file to read out.

to_ellipse()

Convert ICESat elevations to ellipsoid heights, based on the data stored in the HDF5 file.

to_shp(out_filename, driver='ESRI Shapefile', epsg=4326)

Write ICESat data to shapefile.

Parameters:

• out_filename (str) – Filename (optionally with path) of file to read out.
• driver (str) – Name of driver fiona should use to create the outpufile. Default is ‘ESRI Shapefile’.
• epsg (int) – EPSG code to project data to. Default is 4326, WGS84 Lat/Lon.

Example:

>>> donjek_icesat.to_shp('donjek_icesat.shp', epsg=3338)

will write donjek_icesat to a shapefile in Alaska Albers projection (EPSG:3338)

unmask()

Remove a mask if it has been applied. TODO: Not implemented yet!

Returns:

pybob.ICESat.extract_ICESat(in_filename, workdir=None, outfile=None)

Extract ICESat data given the extent of a GeoImg.

Note - currently not supported outside of UiO working environment.

Parameters:

• in_filename (str) – Filename (optionally with path) of DEM to be opened using GeoImg.
• workdir (str) – Directory where in_filename is located. If not given, the directory will be determined from the input filename.
• outfile (str) – name of the output file [default=’ICESat_DEM.h5’]