122
Figure 3.1b shows global, per-capita emission of CO 2 from the combustion of
fossil fuel,^14 which we abbreviate as pCGL. Values of pCGL are presented in units of
metric tons of CO 2 per person per year, abbreviated as t CO 2 ppy. There was a steady
rise in pCGL from 1856, which marks the beginning of the mass production of steel
(Adams and Dirlam 1966 ), until the start of World War I. A hiatus in pCGL then
occurred until the end of World War II, followed by a rapid rise until 1973. Most of
this growth drove the economic development of the US, Europe, and the former
USSR. Many attribute the abrupt leveling off of pCGL in 1973 to the rapid rise in the
price of oil that followed the 6-day Yom Kippur war between Egypt and Israel (first
Oil Shock) (Hamilton 2003 ). This second hiatus in pCGL lasted until 2000. During
this 27 year period, there was a series of world events, such as a second rapid rise in
the price of oil driven by the Iranian revolution (second Oil Shock) and the 1980s
economic recession, all of which contributed to significant increases in carbon effi-
ciency within the developed world. Since 2002, the economic development of China
has led to a third period marked by a rise in pCGL (Le Quéré et al. 2015 ). It is
remarkable how many world events are apparent in the record of per-capita con-
(^14) Per-capita equals global emissions divided by global population; the work capita has Latin roots,
meaning head.
0
10
20
30
40
50
Emission
(Gt CO
yr 2
−1
) CO 2 FF
Population
a
0
2
4
6
8
10
Population
(Billion)
1825 1850 1875 1900 1925 1950 1975 2000
0
1
2
3
4
5
Per−Capita Emission
(t CO
ppy) 2
Steel Manufacture WWI
Market Crash
Great Depression
WWII
US−USSR−Europe Growth
1st Oil Shock
2nd Oil Shock
80s Recession
China Growth
b
Fig. 3.1 Total global emission of atmospheric CO 2. (a) Emission of CO 2 from combustion of fos-
sil fuels, flaring, and cement manufacture (CO 2 FF, grey shaded) as well as global population
(green), from 1820 to 2014; (b) per-capita emission of global atmospheric CO 2 (pCGL) expressed
in metric tons of CO 2 per person, per year (t CO 2 ppy). World events associated with changes in
pCGL are noted. See Methods for further information
3 Paris INDCs