MODIS (version 1.1.7)

runMrt: Run MODIS Reprojection Tool

Description

Specifying input parameters, this function gets MODIS grid data from the archive (HTTP or local) and processes it with the MODIS Reprojection Tool (MRT). At any point, you are highly encouraged to consult the MRT User's Manual (see References) for further information.

Usage

runMrt(
  product,
  collection = NULL,
  begin = NULL,
  end = NULL,
  extent = NULL,
  tileH = NULL,
  tileV = NULL,
  SDSstring = NULL,
  job = NULL,
  datum = "NODATUM",
  zone = NULL,
  projPara = NULL,
  mosaic = TRUE,
  anonym = TRUE,
  ...
)

Arguments

product, collection, begin, end, extent, tileH, tileV, SDSstring, job

See runGdal and functions linked therein.

datum

The output datum used for datum conversion as character, defaults to "NODATUM". Supported datums are "NAD27", "NAD83", "WGS66", "WGS72" and "WGS84", see MRT User's Manual, p. 7-8.

zone

Output zone number as integer, relevant only for UTM projections (i.e., outProj = "UTM". Valid values are <U+2013>60 to +60.

projPara

Output projection parameters as character string, see 'Details'. Ignored if outProj %in% c("SIN", "GEO"). If not specified and using another target projection, the default settings for "GEO" are assumed.

mosaic

A logical that toggles mosaicking on (default) or off. One example where mosaic = FALSE makes sense is for large spatial extents because maximum supported HDF4 filesize is 2GB; if crossed, mosaicking will fail.

anonym

A logical, defaults to TRUE. If FALSE, the job name is appended to the root filename.

...

Additional arguments passed to MODISoptions, see also 'Details' for some MRT specific settings.

Value

A list of output filenames summarized by product and date, see also Value in link[MODIS]{runGdal}.

Details

Please note that in contrast to runGdal, MRT's resample function does not offer an 'overwrite' option, and hence, existing files will be overwritten (see also MRT User's Manual, p. 59). Further arguments that require particular attention when operating MRT are summarized in the following list:

dataFormat: Output file formats include:

• "raw binary" (.hdr and .dat)

• "HDF-EOS" (.hdf)

• "GeoTiff" (.tif; default)

Any other format specified through MODISoptions or 'dataFormat' is ignored and set to "GeoTiff".

outProj: MRT uses calls to the General Cartographic Transformation Package (GCTP) and as such allows projection to the following mapping grids:

• Albers Equal Area ("AEA")

• Equirectangular ("ER")

• Geographic ("GEO")

• Hammer ("HAM")

• Integerized Sinusoidal ("ISIN")

• Interrupted Goode Homolosine ("IGH")

• Lambert Azimuthal ("LA")

• Lambert Conformal Conic ("LCC")

• Mercator ("MERCAT")

• Molleweide ("MOL")

• Polar Stereographic ("PS")

• Sinusoidal ("SIN")

• Transverse Mercator ("TM")

• Universal Transverse Mercator ("UTM")

See also 'References' and MRT User's Manual, pp. 6 and 29.

projPara: Output projection parameters are autodetected for outProj %in% c("SIN", "GEO"):

• "SIN": "6371007.18 0.00 0.00 0.00 0.00 0.00 0.00 0.00 86400.00 0.00 0.00 0.00 0.00 0.00 0.00"

• "GEO": "0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0"

For detailed information on defining paramters for other target projections, please refer to 'Appendix C: Projection Parameters' in the MRT User's Manual, p. 65-66.

References

Dwyer J, Schmidt G (2006) The MODIS Reprojection Tool, 162-177, doi:10.1007/978-3-540-37294-3_9. In: Qu JJ, Gao W, Kafatos M, Murphy RE, Salomonson VV (eds) Earth Science Satellite Remote Sensing. Springer: Berlin, Heidelberg.

Elassal AA (1989) General Cartographic Transformation Package (GCTP), Version II. NOAA Technical Report NOS124 CGS9. NOAA: Rockville, MD, USA. Available online here (2018-09-13).

Land Processes DAAC, USGS Earth Resources Observation and Science Center (2011) MODIS Reprojection Tool User's Manual. Release 4.1, April 2011. Available online here.

See Also

MODISoptions, runGdal.

Examples

# NOT RUN {
geo = runMrt(product="MOD11A1", extent="austria", begin="2010001", end="2010002", SDSstring="101",
             job="ExampleGEOdelme", outProj="GEO")
sin = runMrt(product="MOD11A1", extent="austria", begin="2010001", end="2010002", SDSstring="101",
             job="ExampleSINdelme", outProj="SIN")
utm = runMrt(product="MOD11A1", extent="austria", begin="2010001", end="2010002", SDSstring="101",
             job="ExampleUTMdelme", outProj="UTM", zone = 33)
# }
# NOT RUN {
# }

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