GCAM v6 Documentation: External Inputs for Modeling the Economy

Documentation for GCAM
The Global Change Analysis Model

View the Project on GitHub JGCRI/gcam-doc


External Inputs for Modeling the Economy

GCAM’s economic inputs include information on population and income. These inputs are required for each geopolitical region and historical year.

External Inputs

Description

Table 1: External inputs used for economics1

Name Description Type Source Resolution Unit
Population Population by country and year, used for 1700-1900 External data set Maddison Country/region and year Thousands
Population Population by country and year, used for 1950-2015 External data set UN Country/region and year Thousands
Population Population by country and year, used for 2015-2100 External data set SSP database Country and year Thousands
GDP Historical GDP used for most countries for GDP prior to 2015 External data set USDA Country and year billion US$2010/yr (MER)
GDP Historical GDP used for remaining countries for GDP prior to 2015 External data set World Bank Country and year billion US$2010/yr (MER)
GDP growth rate Near-term growth rate of GDP (2015-2024) External data set IMF Country and year %
GDP GDP by country and year, used for 2025-2100 External data set SSP database, OECD Model Country and year billion US$2005/yr (PPP)
1: Note that this table differs from the one provided on the Economy Modeling Page in that it only lists external inputs to the economics module (either data sources or assumptions). Additionally, the units listed are the units of the raw inputs, rather than the units the GCAM requires.


Note that for the Shared Socioeconomic Pathways (SSPs), different inputs are used for some variables. See SSPs for more information.

Input Data

Population

Historical population is provided in Maddison_population.csv (used for 1700-1900) and UN_popTot.csv (used for 1950-2015).

Future population is provided in SSP_database_v9.csv.

GDP

Historical GDP is provided in USDA_GDP_MER.csv (used through 2015).

Near-term GDP growth rates are provided in IMF_GDP_growth.csv.

Future GDP is provided in SSP_database_v9.csv.