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Table 1. Files in This Numeric Data Package

Brown, S., and G. Gaston. 1996. Tropical Africa: Land Use, Biomass, and Carbon Estimates For 1980. ORNL/CDIAC-92, NDP-055. Carbon Dioxide Information Analysis Center, U.S. Department of Energy, Oak Ridge National Laboratory, Oak Ridge, Tennessee, U.S.A.

>Tables

  1. Files in this numeric data package
  2. Assignment of the biomass indices to potential biomass densities based on forest inventories
  3. Emission of CO2, CO, and CH4 that would have occurred if the measured reduction in dry biomass (from potential to actual in 1980) were burned as fuelwood.
  4. Variable formats of biomax.asc/biomax.vat, land.asc/land.vat, and lakes.asc/lakes.vat
  5. Variable formats of pd80.asc, and bio1980.asc
  6. Variable formats of t_afr.asc/t_afr.pat
  7. Variable formats of africa.asc/africa.patsum1980

Table 1. Files in this numeric data package

----------------------------------------------------------------------------------------------

File File name    File size File description
 no.          (bytes) 

 1  ndp055.txt    68,055  Descriptive file 
 2  trop_africa.prj   809  ARC/INFO projection file with parameters for the 
                 ARC/INFO grids and coverages in this NDP.
 3  biomax.e00  32,740,858  ARC/INFO exported integer grid containing maximum
                 potential biomass density data in Mg/ha.
 4  biomax.asc  10,158,473  ASCII file containing maximum potential biomass density  
                 data in Mg/ha produced using the ARC/INFO GRIDASCII command. 
 5  lakes.e00   32,740,652  ARC/INFO exported integer grid containing the location
                 of all nonseasonal lakes (> 20 km in any direction) in
                 Tropical Africa.
 6  lakes.asc   13,785,885  ASCII file containing the location of all nonseasonal
                 lakes (>20 km in any direction) in Tropical Africa, produced
                 using the ARC/INFO GRIDASCII command.
 7  land.e00   32,740,652  ARC/INFO exported integer grid containing land-use 
                 information classified into four categories.
 8  land.asc    9,032,121  ASCII file containing land-use information classified into
                 four categories produced using the ARC/INFO GRIDASCII command.
 9  intgrid.for     874  FORTRAN retrieval program to read and print the ASCII data
                 files biomax.asc, lakes.asc, and land.asc (output
                 from the ARC/INFO GRIDASCII command for the integer grids:
                 biomax, lakes, and land). 
10  intgrid.sas     356  SAS retrieval program to read and print the ASCII data
                 files biomax.asc, lakes.asc, and land.asc (output from the
                 ARC/INFO GRIDASCII command for the integer grids: biomax,
                 lakes, and land). 
11  bio1980.e00  32,740,307  ARC/INFO exported floating-point grid containing the 
                 calculated actual aboveground live biomass in open and
                 closed forests for 1980 in Mg/ha.
12  bio1980.asc  13,936,491  ASCII file containing the calculated actual aboveground 
                 live biomass in open and closed forests for 1980 in Mg/ha
                 (produced using the ARC/INFO GRIDASCII command).
13  pd80.e00   32,740,307  ARC/INFO exported floating-point grid containing population
                 -density data for 1980 in people per km 2.
14  pd80.asc   12,899,980  ASCII file containing population-density data for 1980 
                 in people per km 2(produced using the ARC/INFO
                 GRIDASCII command).
15  realgrid.for     862  FORTRAN retrieval program to read and print the ASCII data
                 files pd80.asc and bio1980.asc (output from the ARC/INFO
                 GRIDASCII command for the floating point grids: bio1980
                 and pd80). 
16  realgrid.sas     362  SAS retrieval program to read and print the ASCII data
                 files pd80.asc and bio1980.asc (output from the ARC/INFO
                 GRIDASCII command for the floating point grids: bio1980
                 and pd80). 
17  africa.e00    367,612  ARC/INFO exported coverage that contains the amount of land
                 and biomass in open and closed forest by country for 1980.
18  t_afr.e00   1,333,765  ARC/INFO exported coverage that contains population density
                 data for 1960, 1970, 1980, and 1990 for the subnational 
                 political units used in this data base.
19  africa.asc     5,187  ASCII file containing the attribute information associated 
                 with africa.PAT derived from africa.e00 (file 17).
                 and biomass in open and closed forest by country for 1980.
20  africa.for      642  FORTRAN retrieval program to read and print africa.asc 
                 (file 19).
21  africa.sas      422  SAS retrieval program to read and print africa.asc 
                 (file 19).
22  t_afr.asc     78,701  ASCII file containing the attribute information associated
                 with t_afr.PAT derived from t_afr.e00 (file 18).
23  t_afr.for      600  FORTRAN retrieval program to read and print t_afr.asc 
                 (file 22).
24  t_afr.sas      388  SAS retrieval program to read and print t_afr.asc

25  africa_1980bio.gif 29576  Graphic map, "Calculated Actual Aboveground Live Biomass (1980)"

26  africa_biomax.gif 30450  Graphic map, "Maximum Potential Biomass Density"

27  africa_lc.gif   28052  Graphic map, "Land Use"

28  areaclsdforest.gif 15343  Graphic map, "Area of Closed Forest (By Country)"

29  areaopnforest.gif 15279  Graphic map, "Area of Open Forest (By Country)"

30  clsdforestbio.gif 14575  Graphic map, "Mean Biomass of Closed Forests (By Country)"

31  opnforestbio.gif  14903  Graphic map, "Mean Biomass of Open Forests (By Country)"

32  pctforest.gif   13891  Graphic map, "Percent Forest Cover (By Country)"

32  totforestbio.gif  15532  Graphic map, "Total Forest Biomass (By Country)"

33  pop1990.gif    27215  Graphic map, "Population Density - 1990"

34  pop1980.gif    26770  Graphic map, "Population Density - 1980"

35  pop1970.gif    26713  Graphic map, "Population Density - 1970"

36  pop1960.gif    24530  Graphic map, "Population Density - 1960"

37  table.txt     22112  ASCII version of this file (data tables)

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Table 2. Assignment of the biomass indices to potential biomass densities based on forest inventories.

------------------------------------------------------------------------------------------- 
Potential biomass index      Potential biomass (Mg/ha)
------------------------------------------------------------------------------------------- 
    41 - 45               1 
    46 - 50               7 
    51 - 55              15(limit of open forest)
    56 - 60              27
    61 - 65              42
    66 - 70              75
    71 - 75              150
    76 - 80              250
    81 - 85              350
    86 - 90              425
    91 - 95              475
    96 - 100              500
-------------------------------------------------------------------------------------------

Table 3. Emission of CO2, CO, and CH4, that would have occurred if the measured reduction in dry biomass (from potential to actual in 1980) were burned as fuelwood.

------------------------------------------------------------------------------------------- 
                  Emissions from fuelwood burning

                 Closed Forest     Open Forest
------------------------------------------------------------------------------------------- 
Biomass reduction (kg/ha)       86,900       40,500
Carbon reduction (kg/ha)       43,450       20,250

Emissions (g of C/ha)
   C[C02]            34,760 5,648  16,200 2,633
   C[C0]             2,607 869   1,215 405 
   C[CH4]             130 52     61 24  
   C[other1]             5,953       2,774 

Total area (ha)           402.5 x 106    815.6 x 106
Total Emissions (kg)
   C[C02]             14.00 x 1012    13.21 x 1012
   C[C0]              1.05 x 1012    0.99 x 1012
   C[CH4]             0.05 x 1012    0.05 x 1012 
-------------------------------------------------------------------------------------------
1Predominantly charcoal. 
-------------------------------------------------------------------------------------------

Table 4. Variable formats for biomax.asc, lakes.asc, and land.asc

Variable   Variable  Variable Starting Ending   Description 
       type    width   column  column

NCOLS     Integer   5     15    19     The number of columns in 
                             the data file (values per row)
                        
NROWS     Integer   5     15    19     The number of rows in the data file
                       
XLLCORNR    Real   15.5    15    29     The X coordinate of the lower-left
                             corner of a box covering the data area
                      
YLLCORNR    Real   15.5    15    29     The Y coordinate of the lower-left
                             corner of a box covering the data area

CSIZE     Integer   5     15    19     The size in meters of the square
                             grid cells
                      
NODATA    Integer   5     15    19     The value (i.e., -9999) used to
                             represent areas with NO DATA

    ------------------END OF HEADER----------------------

VALUE(1,1)  Integer   5     2     6     An explanation of the "value" field
                             is found at the end of table 2. 
VALUE(1,2)  Integer   5     8    12

...

VALUE(1,1533) Integer   5   9,194   9,198

VALUE(1,1534) Integer   5   9,200   9,204

    ------------------END OF ROW 1-----------------------

VALUE(2,1)  Integer   5     2     6

VALUE(2,2)  Integer   5     8    12

...

VALUE(2,1533) Integer   5   9,194   9,198

VALUE(2,1534) Integer   5   9,200   9,204

    ------------------END OF ROW 2-----------------------

...

VALUE(1502,1534) Int   5   9,200   9,204

    ------------------END OF FILE-------------------------


BIOMAX.ASC/BIOMAX.VAT* - "value" is a single cell of an integer array with 1,502 rows and
       1,534 columns containing the maximum potential aboveground
       biomass in Mg/ha estimated using climatic, topographic, and 
       geomorphic information.

LAKES.ASC/LAKES.VAT* - "value" is a single cell of an integer arry with 1,502 rows and
       1,534 columns showing the location of non-seasonal medium-to-large
       lakes in Africa. Cells may have a value of -999 (NODATA) or 4. A
       value of 4 indicates that 50% or more of the cell's 25 km2
       area was underwater in 1980.

LAND.ASC/LAND.VAT*  - "value" is a single cell of an integer array with 1,502 rows and
       1,534 columns containing one of four land-use classes:

       Value    Land Cover
        1     Closed Forest (includes tropical and seasonal forests)
        2     Open Forest (woodland/wooded savanna)
        3     Grassland Savanna 
        4     Other (includes agriculture)
      -9999     No Data             

*Use the IMPORT GRID command at the ARC prompt to import the *e00 files (biomax.e00,
lakes.e00, and land.e00) into ARC/INFO. The VAT (value attribute table) associated with 
each of these integer grids is populated with a field called VALUE (see descriptions above) 
and a field named COUNT (which records the number of times a VALUE is encountered within the 
grid).

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Table 5. Variable formats for pd80.asc and bio1980.asc.

Variable   Variable  Variable Starting Ending   Description 
       type    width   column  column

NCOLS     Integer   5     15    19     The number of columns in 
                             the data file (values per row)
                        
NROWS     Integer   5     15    19     The number of rows in the data file
                       
XLLCORNR    Real   15.5    15    29     The X coordinate of the lower-left
                             corner of a box covering the data area
                      
YLLCORNR    Real   15.5    15    29     The Y coordinate of the lower-left
                             corner of a box covering the data area

CSIZE     Integer   5     15    19     The size in meters of the square
                             grid cells
                      
NODATA     Real    8.2    15    22     The value (i.e., -9999).00 used to
                             represent areas with NO DATA

    ------------------END OF HEADER----------------------

VALUE(1,1)   Real    8.2    2     9     An explanation of the "value" field
                             is found at the end of table 2. 
VALUE(1,2)   Real    8.2    11    18

...

VALUE(1,1533) Real    8.2  13,790  13,797

VALUE(1,1534) Real    8.2  13,799  13,806

    ------------------END OF ROW 1-----------------------

VALUE(2,1)   Real    8.2    2     9

VALUE(2,2)   Real    8.2    11    18

...

VALUE(2,1533) Real    8.2  13,790  13,797

VALUE(2,1534) Real    8.2  13,799  13,806

    ------------------END OF ROW 2-----------------------

...

VALUE(1502,1534)Real   8.2  13,799  13,806

    ------------------END OF FILE-------------------------


PD80.ASC*  - "value" is a single cell of a real number array with 1,502 rows and
       1,534 columns containing population densities recorded in 
       people per km2 for sub-national political units in
       Tropical Africa. 

BIO1980.ASC* - "value" is a single cell of a real number array with 1,502 rows and
       1,534 columns containing an estimate of the aboveground biomass 
       density of wooded vegetation in 1980 for Tropical Africa. Values
       are in Mg/ha and were estimated based on the maximum potential
       biomass data (BIOMAX.ASC), the land-use data (LAND.ASC and
       LAKES.ASC), and a degradation ratio derived from the population
       information in T_AFR.ASC. 

*Use the IMPORT GRID command at the ARC prompt to import the *e00 files (pd80.e00 and 
bio1980.e00) into ARC INFO. These are floating point grids and therefore do not have a 
VAT (value attribute table) associated with them. Grid values are described above.

------------------------------------------------------------------------------------------------

Table 6. Variable formats of t_afr.asc/t_afr.pat.


Variable   Variable  Variable Starting Ending   Description 
       type    width   column  column

COUNTRY   Character  30     1    30     Country name.
                        
CNTRY_NO   Integer   5     32    36     A unique numeric identification code
                             for each country.
                       
ADMP     Integer   4     38    41     A unique identification code for
                             administrative divisions or 
                             metropolitan places in Tropical Africa.
                      
ADMP_NM   Character  40     43    82     The name of the given division, 
                             metropolitan place, or subnational 
                             political unit.

PD60      Real    8.3    84    91     The population density for 1960 in
                             people/km2
                      
PD70      Real    8.3    93    100     The population density for 1970 in
                             people/km2

PD80      Real    8.3   102    109     The population density for 1980 in
                             people/km2

PD90      Real    8.3   111    118     The population density for 1990 in
                             people/km2

LANDAREA   Integer  10    120    129     The land area in km2 of the
                             given division, metropolitan place, or
                             subnational political unit.

*Use the IMPORT COVER command at the ARC prompt to import t_afr.e00 into ARC/INFO. The 
polygon coverage has a PAT (polygon attribute table) associated with it. The items 
descriptions listed above refer to t_afr.asc (ASCII file) and to items carried
on the T_AFR.PAT.

NOTE: Values of -1.00 for variables PD60, PD70, PD80 and PD90 indicate that data were
not available from the FAO for the given political subdivision. 

------------------------------------------------------------------------------------------------

Table 7. Variables formats of africa.asc/africa.patsum1980.


Variable   Variable  Variable Starting Ending   Description 
       type    width   column  column

COUNTRY   Character  30     1    30     Country name.
                        
CNTRY_NO   Integer   5     32    36     A unique numeric identification code
                             for each country.
                       
TOTCEL    Integer  11     38    48     The number of 5km x 5km cells 
                             within a country.      
                      
TOTAREA    Integer  10     50    59     The land area (km2) in
                             COUNTRY. 

CFAREA    Integer   9     61    69     The amount of land in closed forests
                             (km2) in COUNTRY.
                      
OFAREA    Integer   9     71    79     The amount or land in open forests 
                             (km2) in COUNTRY.

CFBIO     Real   12.1    81    92     The mean biomass of closed forests
                             (Mg/ha) for COUNTRY. 

OFBIO     Real   12.1    94    105     The mean biomass of open forests 
                             (Mg/ha) for COUNTRY. 

TOTBIO     Real   12.4   107    118     The total biomass of forests     
                             (106 Mg) in COUNTRY.

FOREST     Real   12.1   120    131     The percent of COUNTRY that is    
                             forested.

*Use the IMPORT COVER command at the ARC prompt to import africa.e00 into ARC/INFO. The 
polygon coverage has a PAT (polygon attribute table) and an additional INFO table related
to region attributes. The item descriptions listed above refer to items in the africa.asc 
(ASCII file) and to items carried on the INFO table africa.patsum1980

NOTE: There are no NODATA flags in this file. 

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