Emissions Scenarios - IPCC

Summary Discussions and Recommendations
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Table 6-1: Income per capita in the world and by SRES region for the IS92 (Leggett et al., 1992) and four marker scenarios b
2050 and 2100, measured by GDP per capita in 1000 US dollars (at 1990 prices and exchange rates). The additional
illustrative scenarios AlFI and Al T have GDP assumptions similar to the AIB marker, shared with all harmonized scenarios
in the Al family.
Income per Capita by World and Regions (103 1990US$ per capita)
Regions
Year Scenario OECD90 REF IND ASIA ALM DEV WORLD
1990 SRES MESSAGE 19.1 2.7 13.7 0.5 1.6 0.9 4.0
2050 lS92a,b 49.0 23.2 39.7 3.7 4.8 4.1 9.2
lS92c 35.2 14.6 27.4 2.2 2.9 2.5 6.3
IS92d 54.4 25.5 43.4 4.1 5.4 4.6 10.5
IS92e 67.4 38.3 56.9 5.9 7.7 6.6 13.8
lS92f 43.9 21.5 35.8 3.3 4.1 3.6 8.1
AIB 50.1 29.3 44.2 14.9 17.5 15.9 20.8
A2 34.6 7.1 26.1 2.6 6.0 3.9 7.2
Bl 49.8 14.3 39.1 9.0 13.6 10.9 15.6
B2 39.2 16.3 32.5 8.9 6.9 8.1 11.7
2100 lS92a,b 85.9 40.6 69.5 15.0 14.2 14.6 21.5
IS92c 49.2 17.6 36.5 6.4 5.8 6.1 10.1
lS92d 113.9 51.3 88.8 20.3 17.7 19.1 28.2
IS92e 150.6 96.6 131.0 34.6 33.0 33.8 46.0
lS92f 69.7 31.3 54.9 11.9 10.7 11.4 16.8
AIB 109.^ 100.9 107.3 71.9 60.9 66.5 74.9
A2 58.5 20.2 46.6 7.8 15.2 11.0 16.1
Bl 79.7 52.2 72.8 35.7 44.9 40.2 46.6
B2 61.0 38.3 54.4 19.5 16.1 18.0 22.6
6.2.3.1. Energy Systems
Figure 6-3 illustrates that the change of world primary energy
stmcture diverges over time. It shows the contributions of
individual primary energy sources - the percentage supplied by
coal, that by oil and gas, and that by all non-fossil sources taken
together (for simplicity of presentation and because not all
models distinguish between renewables and nuclear energy).
Each comer of the triangle corresponds to a hypothetical
situation in which all primary energy is supplied by a single
source - oil and gas, coal at the left, and non-fossil sources
(renewables and nuclear) to the right. Historically, the primary
energy structure has evolved clockwise according to the two
"grand transitions" (discussed in Chapter 3) that are shown by
the two segments of the "thick black" curve. From 1850 to
1920 the first transition can be characterized as the substitution
of traditional (non-fossil) energy sources by coal. The share of
coal increased from 20% to about 70%, while the share of nonfossils
declined from 80% to about 20%. The second transition,
from 1920 to 1990, can be characterized as the replacement of
coal by oil and gas (while the share of non-fossils remained
essentially constant). The share of oil and gas increased to
about 50% and the share of coal declined to about 30%.
Figure 6-3 gives an overview of the divergent evolution of
global primary energy structures between 1990 and 2100,
regrouped into their respective scenario families and four Al
scenarios groups that explore different technological
developments in the energy systems. The SRES scenarios
cover a wider range of energy stractures than the previous IS92
scenario series, which reflects advances in knowledge on the
uncertainty ranges of future fossil resource availability and
technological change.
In a clockwise direction, Al and ВI scenario groups map the
structural transitions toward higher shares of non-fossil energy
in the future, which almost closes the historical "loop" that
started in 1850. The B2 scenarios indicate a more "moderate"
direction of change with about half of the energy coming from
non-fossil sources and the other half shared by coal on one
side and oil and gas on the other. Finally, the A2 scenario
group marks a stark transition back to coal. Shares of oil and
gas decline while non-fossils increase moderately. What is
perhaps more significant than the diverging developments in
these three marker scenarios is that the whole set of 40
scenarios covers virtually all possible directions of change,
from high shares of oil and gas to high shares of coal and non-