GRASS GIS manual: r.in.usgs

NAME

r.in.usgs - Download user-requested products through the USGS TNM API

KEYWORDS

SYNOPSIS

r.in.usgs

r.in.usgs --help

r.in.usgs [-ik] product=string output_name=name output_directory=name [ned_dataset=string] [nlcd_dataset=string] [nlcd_subset=string] [resampling_method=string] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-i: Return USGS data information without downloading files
-k: Keep extracted files after GRASS import and patch
--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

product=string [required]: USGS data product; Available USGS data products to query; Options: ned, nlcd, naip
output_name=name [required]: Name for output raster map
output_directory=name [required]: Directory for USGS data download and processing
ned_dataset=string: NED dataset; Available NED datasets to query; Options: ned1sec, ned13sec, ned19sec; Default: ned1sec; ned1sec: NED 1 arc-second; ned13sec: NED 1/3 arc-second; ned19sec: NED 1/9 arc-second
nlcd_dataset=string: NLCD dataset; Available NLCD datasets to query; Options: nlcd2001, nlcd2006, nlcd2011; Default: nlcd2011; nlcd2001: National Land Cover Dataset - 2001; nlcd2006: National Land Cover Dataset - 2006; nlcd2011: National Land Cover Dataset - 2011
nlcd_subset=string: NLCD subset; Available NLCD subsets to query; Options: landcover, impervious, canopy; Default: landcover; landcover: Land Cover; impervious: Percent Developed Imperviousness; canopy: Percent Tree Canopy
resampling_method=string: Resampling method to use; Options: default, nearest, bilinear, bicubic, lanczos, bilinear_f, bicubic_f, lanczos_f; Default: default; default: default method based on product; nearest: nearest neighbor; bilinear: bilinear interpolation; bicubic: bicubic interpolation; lanczos: lanczos filter; bilinear_f: bilinear interpolation with fallback; bicubic_f: bicubic interpolation with fallback; lanczos_f: lanczos filter with fallback

DESCRIPTION
NOTES
EXAMPLE
REFERENCES
SEE ALSO
AUTHOR

DESCRIPTION

r.in.usgs downloads and patches selected USGS datasets (NED, NLCD, NAIP) to the current GRASS computational region and coordinate reference system. Associated parameters are automatically passed to The National Map Access API, downloaded to a user-specified local directory, then imported and patched. r.in.usgs supports the following datasets:

ned: National Elevation Dataset
nlcd: National Land Cover Dataset
naip: NAIP orthoimagery

NOTES

NED data are available at resolutions of 1 arc-second (about 30 meters), 1/3 arc-second (about 10 meters), and in limited areas at 1/9 arc-second (about 3 meters).

NLCD data are available for years 2001, 2006, and 2011 (see nlcd_dataset option) at 30m resolution and include Land Cover, Percent Developed Imperviousness, and Percent Tree Canopy (see nlcd_subset option).

NAIP is available at 1 m resolution.

If the i flag is set, only information about data meeting the input parameters is displayed without downloading the data.

By default, downloaded files are kept in the specified output_direcory, so that they can be reused in case different computational region is required. However, unzipped files and imported rasters before patching are removed. If the k flag is set, extracted files from compressed archives are also kept within the download directory after the import.

By default, resampling method is chosen based on the nature of the dataset, bilinear for NED and nearest for NLCD and NAIP. This can be changed with option resampling_method.

EXAMPLE

We will download NED 1/9 arc-second digital elevation model in the extent of raster 'elevation'. First, we just list the files to be downloaded (change output directory depending on the operating system):

g.region raster=elevation
r.in.usgs product=ned ned_dataset=ned19sec output_directory=/tmp output_name=ned -i

USGS file(s) to download:
-------------------------
Total download size:	826.95 MB
Tile count:	4
USGS SRS:	wgs84
USGS tile titles:
USGS NED ned19_n35x75_w078x75_nc_statewide_2003 1/9 arc-second 2012 15 x 15 minute IMG
USGS NED ned19_n36x00_w078x75_nc_statewide_2003 1/9 arc-second 2012 15 x 15 minute IMG
USGS NED ned19_n35x75_w079x00_nc_statewide_2003 1/9 arc-second 2012 15 x 15 minute IMG
USGS NED ned19_n36x00_w079x00_nc_statewide_2003 1/9 arc-second 2012 15 x 15 minute IMG
-------------------------
To download USGS data, remove i flag, and rerun r.in.usgs.

We proceed with the download:

r.in.usgs product=ned ned_dataset=ned19sec output_directory=/tmp output_name=ned
r.colors map=ned_small color=grey

We change the computational region to a smaller extent and create a new DEM, downloaded files will be used.

g.region n=224649 s=222000 w=633000 e=636000
r.in.usgs product=ned ned_dataset=ned19sec output_directory=/tmp output_name=ned_small

For a different extent we download NAIP imagery:

g.region n=224649 s=222000 w=636000 e=639000
r.in.usgs product=naip output_directory=/tmp output_name=ortho

For a different extent we download NLCD land cover:

g.region n=224649 s=222000 w=639000 e=642000
r.in.usgs product=nlcd nlcd_dataset=nlcd2011 nlcd_subset=landcover output_directory=/tmp output_name=nlcd

Figure: Downloaded NED (large and small extent), NAIP orthoimagery, and NLCD land cover

REFERENCES

TNM Access API Guide
National Elevation Dataset
National Land Cover Dataset

AUTHOR

Zechariah Krautwurst, 2017 MGIST Candidate, North Carolina State University
Anna Petrasova, NCSU GeoForAll Lab
(Google Summer of Code 2017, mentors: Anna Petrasova, Vaclav Petras)

SOURCE CODE

Available at: r.in.usgs source code (history)