getrsp {ecochange}

Get remote sensing product

Description

This function processes the extent of a predefined region of interest (polygon geometry or GADM unit) to download ecosystem remote sensing products (ERSP). Downloadable ERSP include Global Surface Water, Forest Change, and Continuous Tree Cover data. See listGP.

Usage

getrsp(roi = NULL, ..., 
    lyrs = NULL, path, 
    rewrite.pass = FALSE, 
    verify.web = FALSE, 
    mc.cores = round(detectCores() * 
        0.6, 0))

Arguments

roi

SpatialPolygonsDataFrame; or sf; or character; or NULL. Region of interest. This can be either 1) a polygon geometry; or 2) the name of a GADM unit (see getGADM); or 3) a NULL value. Default NULL makes the function to print a list of GADM units.

...

If roi is a GADM unit then additional arguments in getGADM.

lyrs

character. Remote-sensing products. Default NULL makes the function to print a list of Downloadable data, see listGP.

path

character. Path name indicating where the variables are stored. If missing then a folder named as 'ecochange' created in a current temporary directory is used.

rewrite.pass

logical. Rewrite password. Only valid to download new NASA Earth data, see details section.

verify.web

logical. Verify in the web whether the URLs used to download the rsp are available. See getOption('webs'). Default FALSE.

mc.cores

numeric. The number of cores. Default uses around 60 percent of the cores.

Details

Downloads of Continuous Tree Cover data require user authentication through the NASA Earth data Login. To obtain a NASA Earth data Login account, please visit: https://urs.earthdata.nasa.gov/users/new.

Value

Path names of the remote sensing products just retrieved, or character vectors suggesting GADM units/Global Products that can be used to download ERSP (see NULL defaults in arguments 'roi' and 'lyrs').

Author(s)

Wilson Lara Henao <[e-mail]> [aut, cre], Victor Gutierrez-Velez [aut], Ivan Gonzalez [ctb], Maria C. Londono [ctb]

References

Pekel, J. F., Cottam, A., Gorelick, N., & Belward, A. S. (2016). High-resolution mapping of global surface water and its long-term changes. Nature, 540(7633), 418-422.

Hansen, M. C., Potapov, P. V., Moore, R., Hancher, M., Turubanova, S. A., Tyukavina, A., ... & Kommareddy, A. (2013). High-resolution global maps of 21st-century forest cover change. science, 342(6160), 850-853.

Sexton, J. O., Song, X. P., Feng, M., Noojipady, P., Anand, A., Huang, C., ... & Townshend, J. R. (2013). Global, 30-m resolution continuous fields of tree cover: Landsat-based rescaling of MODIS vegetation continuous fields with lidar-based estimates of error. International Journal of Digital Earth, 6(5), 427-448.

Examples

## Polygon of the Colombian municipality of Cartagena del Chaira:
    load(system.file('cchaira_roi.RData',package = 'ecochange'))

## A Global Surface Water layer ('seasonality') which covers the
## extent of the polygon is retrieved:

 
 rsp_cchaira <- getrsp(cchaira_roi,
   lyrs = 'seasonality', mc.cores = 2, path = tempdir())
 file.exists(rsp_cchaira)