MAP LAYERS

LAYER NAME:

POPULATION

AUTHOR/CREATOR:

OAK RIDGE NATIONAL LABORATORY

ORGANIZATION:

OAK RIDGE NATIONAL LABORATORY

LINK URL:

http://www.ornl.gov/gist/projects/landscan

CREATION DATE:

April 18, 1999.

CONTACT:

DEPHA

MODIFIED BY:

DEPHA

MODIFICATION DATES:

17/05/2001

ABSTRACT:

The LandScan Global Population Project is a worldwide population database at 30" X 30" resolution for estimating ambient populations at risk. Best available census counts are distributed to cells based on probability coefficients, which, in turn, are based on road proximity, slope, land cover and nighttime lights. Probability coefficients are assigned to each value of each input variable, and a composite probability coefficient is calculated for each LandScan cell.

CONSTRAINTS:

 

The utility of this data is limited due to three factors acknowledged by its authors.

(1)     Census data were obtained from the United Nations Statistical Division, which makes no attempt to evaluate the accuracy of census counts provided by individual nations.

(2)      Census dates, ranging from 1979 to 1994 were projected to 1994 based on annual growth rates by country also provided by the United Nations.

(3)      The algorithm employed to distribute population from administrative units (usually provinces) to cells is purely cartographic and is based on population alone.

 Acknowledgement of the Oak ridge national laboratory and UNDP would be appreciated in products derived from these data.

DATASET SIZE (MB):

54 KB

STATUS

BOUNDING COORDINATES

 EAST:        43.9431                        NORTH:        8.8044

WEST:        31.9862                        SOUTH        -5.9274

POSITIONAL ACCURACY:

 1kilometer or finer.

COORDINATE SYSTEM:

DECIMAL DEGREES

DATUM:

WGS 84

MAP PROJECTION:

GEOGRAPHICAL

FORMAT

GRID FORMAT

 

 

TABLES

SOURCE:

OAK RIDGE NATIONAL LABORATORY

SOURCE PUBLICATION DATE:

April 18, 1999.

CONSTRAINTS:

UNKNOWN

DATASET SIZE (MB):

54KB

ATTRIBUTE RELIABILITY:

UNKNOWN

STATUS:

COMPLETE

FIELDS:

SEE ATTACHED

 

CONTACT NAME:

Alex Lugadiru

ORGANIZATION:

DEPHA PROJECT

POSTAL ADDRESS:

c/o UNDP DDC

P.O. BOX 30552,

NAIROBI,

KENYA.

EMAIL ADDRESS:

alex.lugadiru@unep.org

TELEPHONE NO.:

254-020-7624186/95
LANDSCAN DESCRIPTION

 

Information on the contents of the files is provided below.

 

FILE

DESCRIPTION

HDR

The DEM header file is an ASCII text file containing size and coordinate information for the DEM.

PRJ

Projection information file. An ASCII text file which describes the projection of the DEM, and source map image.

STA

Statistics file. An ASCII text, the band number, minimum value, maximum value, mean value and standard deviation of the values in the DEM data file.

VAT

value attribute table

 

                                                               

Cell size = 0.008°