PREDICTIONS – 10 Years Later - Santa Fe Institute

APPENDIX C
COMPETITION BETWEEN TRANSPORT INFRASTRUCTURES IN THE
UNITED STATES
Percentage of total length
90.9% 1
76% 0.5
50% 0
CANALS RAILWAYS ROADS
24% -0.5
AIRWAYS
9.1% -1
3.1% -1.5
1% -2
1800 1850 1900 1950 2000 2050
APPENDIX FIGURE 7.1 The sum total in mileage among all transport infrastructures
is split here among the major types. A declining percentage does not mean
that the length of the infrastructure is shrinking but rather that the total length is
increasing. Between 1860 and 1900 the amount of railway track increased, but
its share of the total decreased because of the dramatic rise in road mileage. The
fitted lines are projected forward and backward in time. The share of airways is
expected to keep growing well into the second half of the twenty-first century.
The small circles show some deviation between the trajectories predicted fifteen
years ago and what happened since then (see text). ∗
∗ Adapted from a graph by Nebojsa Nakicenovic in “Dynamics and Replacement of U.S.
Transport Infrastructures,” in J.H. Ausubel and R. Herman, eds, Cities and Their Vital
Systems, Infrastructure Past, Present, and Future, (Washington, DC: National
Academy Press, 1988). Reprinted by permission of the publisher.
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