Population Maps of Latin America

Glenn Hyman, Andy Nelson, German Lema

International Center for Tropical AgricultureCali, Colombia

Outline

• Why we need population maps

• The Database

• Gridding methods

• Verification

• Relationships between population and other variables

• Future Research

Why we need population maps

Raster Population Surface

Potential Agricultural Productivity

Population summedby zones

Note: Areas en black are cities.Zones in Purple are higher rural population densities. Zones in green are low rural population densities.

Table 7. Potential Agricultural Productivity and Rural Population in Latin America

103 kcal. Ha-1 yr-1 Area (km2) Rural Population

High level of inputs

cold climates 605,489 6,266,441< 500 185,006 14,324,680

501-1000 78,097 241,3711001-2500 640,171 10,612,3652501-5001 725,593 13,710,7785001-7500 482,869 6,522,0247501-10000 581,880 10,154,42610001-12500 423,531 28,478,42412501-15000 306,160 29,708,45215001-20000 390,005 29,968,818

> 20000 803,669 22,745,092

Low level of inputs

cold climates 613,040 8,254,366< 500 883,568 17,896,746

501-1000 120,468 134,432,5601001-2500 176,031 46,270,5042501-5001 400,196 46,998,612

Note: Low input level map is for Latin America and the Caribbean High input level map only includes South America

The Database

10,400 unitsmost are municipios

Municipiolevel

Parroquia level

CIAT Administrative Division Database

Population Density in Latin America and the Caribbean

< 1

1-10

10-25

25-50

50-100

>100

people/km2

Source: CIAT’s Population Database

r = ( ln ( pf / pi ) ) / t

where:r = rateln= logaritmo naturalpf = population at final timepi = population at initial timet = period of time

• Growth rates were calculated from ECLAC’s population database at the department level• An exponential growth rate function was used• Population was estimated to the year 2000• We used figures from the last 2 population censuses at department level to calculate population growth rates

Gridding Methods

• Equal distribution (total population / number of cells in unit)

• Pycnophylactic

• Accessibility

• Weight model

Roads and Rivers from DCW

Caminos y Rios

Pendientes

Luces Nocturnas

Nighttime Lights

Slope from 1 km DEM

Continental ScaleAccessibility Mapping

Model based on traveltime to populated places

Model uses roads, rivers,populated places, slope, and land cover to estimatetravel time

Population from Census

Accessibility Model

Verification

Municipio Distrito

Ecuador 203 976

Peru 191 1836

Verification data from different scales and independently collected

Model where municipal leveldata is verified from data aggregated to finer district level

PERU

Variable N Mean Minimum Maximum CV Sum ------------------------------------------------------------------------ DAREA 1781 196.40 0.13 16741.92 371.72 349797.39 DPYCNO 1781 190.89 0.17 20361.68 378.29 339991.89 DACCESS 1781 168.63 0.04 17139.46 381.31 300337.16 DACCESS_2 1781 160.16 0.02 15857.71 352.97 285248.06 DWEIGHT 1781 148.56 0.02 11166.89 338.47 264588.71

ECUADOR Variable N Mean Minimum Maximum CV Sum ---------------------------------------------------------------------- DAREA 918 235.06 0.01 17803.46 354.12 215788.54 DPYCNO 918 235.38 0.20 16337.44 342.67 216080.66 DACCESS 918 176.95 0.12 5001.63 248.19 162441.51 DACCESS_2 918 178.11 0.22 4116.35 233.95 163508.02 DWEIGHT 918 154.62 0.59 5022.37 235.05 141944.20

Modeled population counts compared to census datafor Peru and Ecuador verification data sets: percentagedifferences

Ecuador

BEST Frequency Percent ----------------------------- area 150 16.5 access 154 16.9 access_2 168 18.5 pycno 183 20.1

weight 255 28.0

Peru

BEST Frequency Percent ----------------------------- area 265 15.0 access 320 18.1 access_2 404 22.8 pycno 291 16.4 weight 492 27.8

Relationships between population and other variables

Department Population vs Night Light Area

R2 = 0.8103

0

10000

20000

30000

40000

50000

0.0E+00 5.0E+06 1.0E+07 1.5E+07 2.0E+07 2.5E+07 3.0E+07 3.5E+07

SAO PAULO

RIO DEJ ANEIRO

Department Population vs Summed Frequency

R2 = 0.8727

0

500000

1000000

1500000

2000000

0.0E+00 5.0E+06 1.0E+07 1.5E+07 2.0E+07 2.5E+07 3.0E+07 3.5E+07

Distribution of Rural Population in Latin America and the Caribbean

Central America, the Central America, the Andes, and the Andes, and the Caribbean have the Caribbean have the highest rural population highest rural population densitiesdensities..

0-11-1010-2020-3030-4040-5050-6060-7070-8080-9090-100>100No Data

People per km2

Source: CEPAL

Rural Model

Variable R2 Cumulative R2

URBANO 0.52 0.52 AGUA 0.23 0.75

PEN25_50 0.06 0.81

Variable Parameter F Prob > F Estimate

AGUA 441.14117780 346.35 0.0001 URBANO 4373.57019841 774.39 0.0001

PEN25_50 110.28701024 111.94 0.0001

Urban Model

Variable R2 Cumulative

R2 URBANO 0.7548 0.7548 LUC100 0.0376 0.7924 LUC25 0.0146 0.8069

AGUA 0.0133 0.8202

Variable Parameter F Prob>F Estimate

URBANO 36362.6 694.94 0.0001 LUC100 2564.6 80.49 0.0001 LUC25 -2558.5 34.26 0.0001 AGUA 873.8 23.48 0.0001

Future Work

• Gridding using statistical results • Further verification using data from Peru,

Honduras and Ecuador

• Compare to other work (eg. ORNL 1 km database)

• A Rural population map?

• New Map with 2000 Census round focusing onAmazon basin, Central American hillsides, Latin American savanas.