Saudi Arabia Population Map Metadata Report

Prediction Weighting Layer Used in Population Redistribution

The data presented below represent the predicted number of people per ~100 m pixel as estimated using the random forest (RF) model as described in Stevens, et al. (In Press). The following pages contain a description of the RF model and its covariates, their sources and any metadata collected for each covariate. The prediction weighting layer is used to dasymetrically redistribute the census counts and project counts to match estimated populations based on UN estimates for the final population maps provided by AfriPop, AsiaPop and AmeriPop.

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Saudi Arabia Census Data and Observed Population Density

These data are the population density values used to estimate the RF model used to create the prediction weighting layer you see above. Values represent population density as measured by people per hectare and calculated from population counts within each census unit. These values are used as the dependent variable during model estimation.

Saudi Arabia Census Data 2010

Folder: Census
File Name: SAU_Census_10.shp
Source:http://www.cdsi.gov.sa/en/76
Description:Data arranged by region and governorate then broken down into Saudis and Non Saudis and by gender.
Class: polygon
Derived Covariates:
area, buff, zones,

class       : SpatialPolygonsDataFrame 
features    : 118 
extent      : -536171, 1623089, 1812344, 3572570  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
variables   : 18

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Random Forest Model and Diagnostics

These output and figures outline the estimated RF model that is used to predict the population density weighting layer. The model is fitted to the population density values for the preceding census data using covariates aggregatedfrom the ancillary data sources summarized following the model diagnostics.


Call:
 randomForest(x = x_data, y = y_data, ntree = popfit$ntree, mtry = popfit$mtry,      nodesize = length(y_data)/1000, importance = TRUE, proximity = TRUE) 
               Type of random forest: regression
                     Number of trees: 500
No. of variables tried at each split: 8

          Mean of squared residuals: 0.54
                    % Var explained: 82

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Covariate Metadata

Remotely-sensed, Classified Landcover

Folder: Landcover
File Name: SAU_RF_LC_INPUT_2.tif
Source: GlobCover, 2009, (300m), http://due.esrin.esa.int/globcover/; MODIS 500m Global Urban Extent, 2000-2001, http://sage.wisc.edu/people/schneider/research/data.html
Description: Landcover from the GlobCover product, reclassified to match AfriPop coding and eventually broken down into binary classifications by aggregated land cover type (see Linard, et al., 2010 and Gaughan, et al. 2013 for category information).
Class: raster
Derived Covariates:
prp011, cls011, dst011, prp040, cls040, dst040, prp130, cls130, dst130, prp140, cls140, dst140, prp150, cls150, dst150, prp160, cls160, dst160, prp190, cls190, dst190, prp200, cls200, dst200, prp210, cls210, dst210, prp230, cls230, dst230, prp240, cls240, dst240, prp250, cls250, dst250, prpBLT, clsBLT, dstBLT,

class       : RasterBrick 
dimensions  : 18156, 21619, 392514564, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : -546220, 1615680, 1779281, 3594881  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : C:\Local\Geodata\RFmap\data\SAU\Landcover\Derived\landcover.tif 
names       : landcover 
min values  :        11 
max values  :       240 

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MODIS 17A3 2010 Estimated Net Primary Productivity, 1km

Folder: NPP
File Name: DEFAULT: MODIS 17A3 2010
Source: United States Geological Survey (USGS)
Description: MODIS 17A3 version-55 derived estimates of net primary productivity for the year 2010, estimated for 1km pixel sizes and subset and resampled to match the available land cover and final population map output requirements.
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 18156, 21619, 392514564, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : -546220, 1615680, 1779281, 3594881  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : C:\Local\Geodata\RFmap\data\SAU\NPP\Derived\npp.tif 
names       :  npp 
min values  :    0 
max values  : 8763 

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Suomi NPP VIIRS-Derived 2012 Lights at Night, 15 arc-second

Folder: Lights
File Name: DEFAULT: VIIRS 2012
Source: http://ngdc.noaa.gov/eog/viirs/download_viirs_ntl.html
Description: These 'Lights at Night' data were derived from imagery collected by the Suomi National Polar-orbiting Partnership (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor. Data were collected in 2012 on moonless nights and though background noise associated with fires, gas-flares, volcanoes or aurora have not been removed it represents the best-available data for night-time light production.
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 18157, 21619, 392536183, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : -546220, 1615680, 1779181, 3594881  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : C:\Local\Geodata\RFmap\data\SAU\Lights\Derived\lights.tif 
names       : lights 
min values  :  -0.15 
max values  :  31355 

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WorldClim/BioClim Mean Annual Temperature 1950-2000, 30 arc-second

Folder: Temp
File Name: DEFAULT: BIO1
Source: http://www.worldclim.org/current
Description: WorldClim/BioClim 1950-2000 mean annual precipitation (BIO12) and mean annual temperature (BIO1) estimates (Hijmans et al., 2005) were downloaded, mosaicked and subset to match the extent of our land cover data for the mapping of this region.
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 18157, 21619, 392536183, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : -546220, 1615680, 1779181, 3594881  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : C:\Local\Geodata\RFmap\data\SAU\Temp\Derived\temp.tif 
names       : temp 
min values  :   18 
max values  :  315 

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WorldClim/BioClim Mean Annual Precipitation 1950-2000, 30 arc-second

Folder: Precip
File Name: DEFAULT: BIO12
Source: http://www.worldclim.org/current
Description: WorldClim/BioClim 1950-2000 mean annual precipitation (BIO12) and mean annual temperature (BIO1) estimates (Hijmans et al., 2005) were downloaded, mosaicked and subset to match the extent of our land cover data for the mapping of this region.
Class: raster
Derived Covariates:
,

class       : RasterBrick 
dimensions  : 18157, 21619, 392536183, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : -546220, 1615680, 1779181, 3594881  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : C:\Local\Geodata\RFmap\data\SAU\Precip\Derived\precip.tif 
names       : precip 
min values  :      2 
max values  :    609 

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Roads 2014

Folder: Roads
File Name: SAU_Roads.shp
Source:OpenstreetMap (OSM) and Diva GIS
Description:Data was reclassified into three classes: Primary (Major),Secondary and Tertiary (Minor) roads based on the official map of KSA and the inherent classification within the OSM Data.
Class: linear
Derived Covariates:
cls, dst,

class       : SpatialLinesDataFrame 
features    : 242725 
extent      : -534663, 1621154, 1812590, 3556062  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
variables   : 1

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River Network

Folder: Rivers
File Name: DEFAULT: hydro/watrcrsl
Source: National Geospatial-Intelligence Agency (NGA), http://geoengine.nga.mil/geospatial/SW_TOOLS/NIMAMUSE/webinter/rast_roam.html
Description: The VMAP0 data area downloaded as separate files, grouped roughly by continent, and merged into individual shapefiles for subsetting and further processing for population mapping efforts. These data were obtained directly from the original VMAP0 data sources provided by the NGA and pre-processed using Military Analyst in ArcGIS 10.0.
Class: linear
Derived Covariates:
dst,

class       : SpatialLinesDataFrame 
features    : 9029 
extent      : -519270, 1615649, 1801520, 3586310  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
variables   : 9

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Settlements 2016

Folder: Populated
File Name: Saudi_Settlement_Points.shp
Source: MoH (Information and Communication Technology,Software and Application Department) Kingdom of Saudi Arabia
Description:Data provided to Prof. Bob Snow on 22/05/2016 by Eng. Murry Abdullah Gammash of the MoH (Information and Communication Technology,Software and Application Department) Kingdom of Saudi Arabia
Class: point
Derived Covariates:
prp, cls, dst,

class       : SpatialPointsDataFrame 
features    : 18837 
extent      : -508406, 1567290, 1816342, 3551959  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
variables   : 5

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Inland Waterbodies

Folder: Waterbodies
File Name: DEFAULT: hydro/watrcrsl
Source: National Geospatial-Intelligence Agency (NGA), http://geoengine.nga.mil/geospatial/SW_TOOLS/NIMAMUSE/webinter/rast_roam.html
Description: The VMAP0 data area downloaded as separate files, grouped roughly by continent, and merged into individual shapefiles for subsetting and further processing for population mapping efforts. These data were obtained directly from the original VMAP0 data sources provided by the NGA and pre-processed using Military Analyst in ArcGIS 10.0.
Class: polygon
Derived Covariates:
cls, dst,

class       : SpatialPolygonsDataFrame 
features    : 5008 
extent      : -546216, 1615384, 1811665, 3594800  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
variables   : 10

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Urban extents 2010

Folder: Urban
File Name: SAU_Urban_etx.shp
Source: http://www.citypopulation.de/SaudiArabia.html
Description: The list of towns and cities in Saudi Arabia was downloaded from citypopulation.de. This list had all major towns with population greater than 20,000 as per the Saudi Arabia 2010 census. This city Population list was compiled from the National Statistics website of Saudi Arabia. All the names were checked and confirmed with Geonames, Google Earth and Open Street Maps. The extents of the towns were then digitized in Google Earth; towns very close to each other were combined.
Class: polygon
Derived Covariates:
cls, dst,

class       : SpatialPolygonsDataFrame 
features    : 1482 
extent      : -546212, 1449922, 1827673, 3525879  (xmin, xmax, ymin, ymax)
coord. ref. : NA 
variables   : 2

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Elevation and Derived Slope, 3 second

Folder: Elevation
File Name: DEFAULT: Void-Filled DEM.gdb
Source: HydroSHEDS Void-Filled DEM (Lehnert, et al., 2006), http://hydrosheds.cr.usgs.gov/dataavail.php
Description: The HydroSHEDS data are the result of an effort to provide a globally consistent dataset consisting of NASA's Shuttle Radar Topography Mission (SRTM) data and have been processed, void-filled and corrected for use at large scales.
Class: raster
Derived Covariates:
, slope,

class       : RasterBrick 
dimensions  : 18157, 21619, 392536183, 1  (nrow, ncol, ncell, nlayers)
resolution  : 100, 100  (x, y)
extent      : -546220, 1615680, 1779181, 3594881  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=utm +zone=38 +datum=WGS84 +units=m +no_defs +ellps=WGS84 +towgs84=0,0,0 
data source : C:\Local\Geodata\RFmap\data\SAU\Elevation\Derived\elevation.tif 
names       : elevation 
min values  :      -417 
max values  :      4384