YiFan Li 1 and Ashbindu Singh 2

1
Methodologies of Creation of Gridded Global
Population Datasets for 1990 and Their
Applications in Compilation of Gridded Emission
Inventories for Different Pollutants

• Yi-Fan Li (1) and Ashbindu Singh (2)
• (1) Air Quality Research Branch, Meteorological
  Service of Canada, Environmental Canada
• (2) UNEP/GRID-Sioux Falls, EROS Data Centre,
  Sioux Falls, SD 57198, USA

2
Introduction

• In 1996, with financial support from the United
  Nations Environment Programme (UNEP), Environment
  Canada has created a population database
  depicting the worldwide distribution of
  population for 1990 with a 1?X1?
  latitude/longitude resolution
• Over 75,000 registered users have accessed or
  downloaded the datasets from UNEP/GRID website
  since the data was released.

Environment Canada
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Methodology

• Point sources city population
• Around 6,000 cities and their populations from
  Rand McNally World Atlas
• Area sources
• 90,000 cities and towns as surrogate data
• global rural population distribution factor
• Population data for United States, Canada, China,
  and the former Soviet Union were replaced by
  better census datasets

Environment Canada
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Global city population in 1990

• Around 6,000 cities with population 50K
  inhabitants (with some exceptions) are located in
  the grid cells
• For cities with data from earlier than 1985, a
  growth rate of 0.63 are applied in developed
  countries, and 2.13 for those in less developed
  countries
• Then the average annual urban growth rate from UN
  for different countries are used to transfer city
  population of 1985-1989 to values of 1990.

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City population in 1990 with 1? x1? lat/long
resolution
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Global rural population distribution factor for
1990

• Around 20,500 major cities and 69,000 minor
  cities from 223 countries were allocated to
  12,200 grid cells
• Population factors were assigned to each city 2
  for each major city, and 1 for each minor city
• The assigned population factors in each grid cell
  were summed up for each country, and a rural
  population distribution factor dataset for 1990
  with 1?X1? degree latitude/longitude resolution
  was obtained.

Environment Canada
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Global residence area with 1? x1? lat/long
resolution
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Global rural population distribution

• The total rural population was obtained by
  subtracting the global city population in 1990
  from the total of national populations for 1990.
  This total rural population was allocated to
  grid cells according to the formula
• Pop. factor
  in the cell for the country
• Rural pop in cell Total rural population X
  ???????????????
• Total pop. factor for the
  country

Environment Canada
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Refinement of the Dtataset

• The data for the following countries are replaced
  by better datasets.
• United States Census Data
• Two 1990 census population datasets for
  approximately 23,400 USA cities and 3,141
  counties were used.
• Canadian Data
• A gridded Canadian population dataset for 1991
  with a 1/6 latitude and 1/4 longitude grid
  resolution was obtained from the Canadian
  National Pollutant Release Inventory, and scaled
  to 1990 for each grid by a factor of
  26,647/27,297 (Canadian population for 1990 is
  26,647,000, for 1991 is 27,297,000).

Environment Canada
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Refinement of the Dtataset (Ctn.)

• Chinese Population Data
• The Chinese 1990 census data, which contains
  population data for 2,405 administration units
  (cities and counties), were allocated over the
  cities and county capitals.
• Former Soviet Union Data
• The 1990 population data for 15 former USSR
  republics were obtained from Dr. Alexey G.
  Ryaboshapko, Institute of Global Climate and
  Ecology, Moscow, Russia. City and town population
  figures were allocated to each cell according to
  its latitude and longitude. The rural population
  was determined separately for each county (raion)
  in Russia, and for each province (oblast) in
  other former Soviet Republics.

Environment Canada
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Gridded Global Population Datasets for 1990

• The 1990 global population dataset contains
  16,762 records and covers 209 countries and
  11,748 grid cells ? about 1.8 of the total
  648,000 grid cells worldwide. The population of
  the countries in the database is 5.291 billion,
  within 0.07 of the FAOs total estimated world
  population for 1990, of 5,295 billion.

Environment Canada
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Global population for 1990 with 1? x1? lat/long
resolution
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Applications in Compilation of Gridded Emission
Inventories for Different Pollutants

• Gridded population data are a very important
  surrogate for distributing area sources of a
  large amount of pollutants
• This database has been accepted as the standard
  population data by Global Emissions Inventory
  Activities (GEIA), a component of the
  International Global Atmospheric Chemistry core
  project of the International Geosphere -
  Biosphere Program
• GEIA Website http//www.geiacenter.org

Environment Canada
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Selected Publications in which the population
data were used as surrogate

• Li, Y. F., Zhang, Y. J., Cao, G. L., Liu, Jian
  Hui, and Barrie, L.A., 1998, Distribution of
  seasonal SO2 emissions from fuel combustion and
  industrial activities in Shanxi, China, with 1/6o
  X 1/4o longitude/latitude resolution,
  Atmospheric Environment, 33, 257-265.
• Pacyna, J. M., Scholtz, M. T., and Li, Y. F.,
  1995, global budget of metal sources,
  Environmental Reviews, Vol. 3, 145-159.
• Brook, Jeffery, Zhang, Leiming, and Li, Yi-Fan,
  1999, Modelling of dry deposition velocities on
  local and regional scales. Part II Modelled dry
  deposition over south-eastern Canada Atmospheric
  Environment, 33, 5053-5070
• McCulloch, A., M. Aucott, C.M. Benkovitz, T.E.
  Graedel, G. Kleiman, P.M. Midgley, Y.F. Li, 1999,
  Global emissions of hydrogen chloride and
  chloromethane from coal combustion, incineration
  and industrial activities the Reactive Chlorine
  Emissions Inventory, J. Geophys. Res., 104, D7,
  8391-8403
• Aucott, M., A. McCulloch, T. E. Graedel, G.
  Kleiman, P. M. Midgley, and Y.F. Li, 1999,
  Anthropogenic emissions of trichloromethane
  (chloroform, CHCl3) and chlorodifluoromethane
  (HCFC-22) Reactive Chlorine Emissions
  Inventory, J. Geophys. Res., 104, D7, 8405-8415

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Selected Publications in which the population
data were used as surrogate

• McCulloch, A., M. L. Aucott, T. E. Graedel, G.
  Kleiman, P. Midgley, and Y.F. Li, 1999,
  Industrial emissions of trichloroethene,
  tetrachloroethene, and dichloromethane The
  Reactive Chlorine Emissions Inventory, J.
  Geophys. Res., 104, D7, 8417-8427
• Keene, William C., M. Aslam K. Khalil, David J.
  Erickson, III, Archie McCulloch, Thomas E.
  Graedel, Michael L. Aucott, Sun Ling Gong, David
  B. Harper, Gary Kleiman, Valentine Koropalov,
  Jurgen M. Lobert, Pauline Midgley, Robert M.
  Moore, Christophe Seuzaret, William T. Sturges,
  Len A. Barrie, Jennifer A. Logan, Y.F. Li, 1999,
  Composite global emissions of reactive chlorine
  from anthropogenic and natural sources The
  Reactive Chlorine Emissions Inventory, J.
  Geophys. Res., 104, D7, 8429-8440

Environment Canada
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Acknowledgments

• Financial support from Environment Canada and
  UNEP made this work possible
• Thanks also to Dr. Alexey G. Ryaboshapko,
  Institute of Global Climate and Ecology, Moscow,
  Russia for providing population data of former
  Soviet Union
• Comments sent to us by many users of the data are
  highly appreciated.