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 for further information.

Usage

runMrt(
  product,
  collection = NULL,
  begin = NULL,
  end = NULL,
  extent = NULL,
  tileH = NULL,
  tileV = NULL,
  SDSstring = NULL,
  job = NULL,
  datum = c("NODATUM", "NAD27", "NAD83", "WGS66", "WGS72", "WGS84"),
  zone = NULL,
  projPara = NULL,
  mosaic = TRUE,
  anonym = TRUE,
  ...
)

Value

A list of output file names summarized by product and date, see also Value in runGdal().

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 -60 to +60.
projPara: Output projection parameters as character string, see Details. Ignored if 'outProj' is one of 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 file size 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.

Author

Matteo Mattiuzzi, Forrest Stevens and Florian Detsch

Details

Please note that in contrast to runGdal(), MRT's resample function does not offer an 'overwrite' option, meaning that 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 parameters 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, tools:::Rd_expr_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).

Examples

Run this code

if (FALSE) {
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)
}

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