popRFdemo: Function to demo the popRF package using WorldPop input data.

In popRF: Random Forest-Informed Population Disaggregation

Description

This function allows the user to generate a population layer using the WorldPop geospatial covariates and subnational census-based population estimates for 230 countries. All input datasets use a geographical coordinate system (GCS) with WGS 1984 datum (EPSG:4326) in Geotiff format at a resolution of 3 arc-second (0.00083333333 decimal degree, approximately 100m at the equator). Mastergrid of sub-national administrative unit boundary was rasterised by CIESIN.

Following covariates will be downloaded and used to disaggregat population (2020 year) from census units into grid cells.

• subnational_admin_2000_2020.tif - sub-national units provided by nationalEAs

• esaccilc_dst011_2015.tif - Distance to ESA-CCI-LC cultivated area edges 2015.

• esaccilc_dst040_2015.tif - Distance to ESA-CCI-LC woody-tree area edges 2015.

• esaccilc_dst130_2015.tif - Distance to ESA-CCI-LC shrub area edges 2015.

• esaccilc_dst140_2015.tif - Distance to ESA-CCI-LC herbaceous area edges 2015.

• esaccilc_dst150_2015.tif - Distance to ESA-CCI-LC sparse vegetation area edges 2015.

• esaccilc_dst160_2015.tif - Distance to ESA-CCI-LC aquatic vegetation area edges 2015.

• esaccilc_dst190_2015.tif - Distance to ESA-CCI-LC artificial surface edges 2015.

• esaccilc_dst200_2015.tif - Distance to ESA-CCI-LC bare area edges 2015.

• esaccilc_dst_water_100m_2000_2012.tif - ESA-CCI-LC inland waterbodies 2000-2012.

• coastline_100m_2000_2020.tif - Distance to coastline 2000-2020.

• dst_roadintersec_100m_2016.tif - Distance to OSM major road intersections.

• dst_waterway_100m_2016.tif - Distance to OSM major waterways.

• dst_road_100m_2016.tif - Distance to OSM major roads.

• px_area.tif - Grid-cell surface areas.

• srtm_slope_100m.tif - SRTM-based slope 2000 (SRTM is Shuttle Radar Topography Mission).

• srtm_topo_100m.tif - SRTM elevation 2000.

• viirs_100m_2016.tif - VIIRS night-time lights 2015 (VIIRS is Visible Infrared Imaging Radiometer Suite).

• wdpa_dst_cat1_100m_2017.tif - Distance to IUCN strict nature reserve and wilderness area edges 2017.

• dst_bsgme_100m_2020.tif - Distance to predicted built-settlement extents in 2020.

All downloaded files will be saved into subdirectory covariates.

Usage

popRFdemo(project_dir, 
          country="NPL", 
          cores=0, 
          quant=TRUE, 
          ftp=TRUE, 
          verbose=TRUE, 
          log=TRUE, ...)

Arguments

project_dir	Path to the folder to save the outputs.
country	character. ISO of the country (see country codes). Default one is NPL (Nepal)
cores	is a integer. Number of cores to use when executing the function. If set to 0 (max_number_of_cores - 1) will be used based on as many processors as the hardware and RAM allow. Default is cores = 0.
quant	If FALSE then quant will not be calculated
ftp	is logical. TRUE or FALSE: flag indicating whether FTP or HTTPS of WorldPop data hub server will be used. Default is ftp = TRUE.
verbose	is logical. TRUE or FALSE: flag indicating whether to print intermediate output from the function on the console, which might be helpful for model debugging. Default is verbose = TRUE.
log	is logical. TRUE or FALSE: flag indicating whether to print intermediate output from the function on the log.txt file. Default is log = FALSE.
...	Additional arguments: binc: Numeric. Increase number of blocks sugesting for processing raster file. boptimise: Logical. Optimize total memory requires to processing raster file by reducing the memory need to 35%. bsoft: Numeric. If raster can be processed on less then cores it will be foresed to use less number of cores. nodesize: Minimum size of terminal nodes. Setting this number larger causes smaller trees to be grown (and thus take less time). See randomForest for more details. Default is nodesize = NULL and will be calculated as length(y_data)/1000. maxnodes Maximum number of terminal nodes trees in the forest can have. If not given, trees are grown to the maximum possible (subject to limits by nodesize). If set larger than maximum possible, a warning is issued. See randomForest for more details. Default is maxnodes = NULL. ntree Number of variables randomly sampled as candidates at each split. See randomForest for more details. Default is ntree = NULL and ntree will be used popfit$ntree mtry Number of trees to grow. This should not be set to too small a number, to ensure that every input row gets predicted at least a few times. See randomForest for more details. Default is ntree = NULL and ntree will be used popfit$mtry.

Value

Raster* object of gridded population surfaces.

References

• Global spatio-temporally harmonised datasets for producing high-resolution gridded population distribution datasets doi: 10.1080/20964471.2019.1625151.

• WorldPop (www.worldpop.org - School of Geography and Environmental Science, University of Southampton; Department of Geography and Geosciences, University of Louisville; Departement de Geographie, Universite de Namur) and Center for International Earth Science Information Network (CIESIN), Columbia University (2018). Global High Resolution Population Denominators Project - Funded by The Bill and Melinda Gates Foundation (OPP1134076) doi: 10.5258/SOTON/WP00649.

Examples

## Not run: 
popRFdemo(project_dir="/home/user/demo",
          country="NPL", 
          cores=0)

## End(Not run) 

popRF documentation built on July 26, 2021, 9:07 a.m.