comment:
This is an IPAT-S script. IPAT-S is an open-source scripting language
for developing sustainability scenarios. It can be run using the free
IPAT-S software, available from:

	http://ipat-s.kb-creative.net/

For more information, please contact the author of IPAT-S,
Eric Kemp-Benedict (eric@kb-creative.net)
:comment

# This script expands on the "Basic Demo" script, by reporting
# cumulative CO2 emissions, using the "accumulate" function

base year 1997
scenario years 2010 2020

# Major variables
summable variable Population = 300, <340, 370>   # millions of people
report Population as "Population (millions)"

summable variable CO2
CO2.by = 1.7        # billion tonnes of carbon ('by' means base year)
ratio Affluence = growth(<2.0%>)
ratio Technology = index[<0.9, 0.8>]

chain	Population >> Technology * Affluence -> CO2

report CO2 as "CO2 (GtC)"
report 1000 * CO2/Population as "CO2 per person (ktC/cap)"

# Report cumulative emissions
report accumulate(CO2) as "Cumulative Emissions since 1997 (GtC)"