Geoscience Reference
In-Depth Information
The uncertainties about climate change were dramatized in a strik-
ing way by a group of MIT climate scientists. Instead of just publishing
their results, they gave a press conference with a roulette wheel show-
ing the possible outcomes. Their results indicated that global warming
by 2100 would be almost half again as large as other estimates, with a
central estimate of 5
1
⁄
4
°C as compared to the 3
1
⁄
2
°C shown in Figure 9.
While their results are an outlier among those of other modeling teams,
they emphasize the great uncertainties that scientists confront in mak-
The bottom line is that if no policies are made to slow global warm-
ing, the central estimate is that the average global temperature by 2100
will be about 3
1
⁄
2
°C above the 1900 level. There is considerable uncer-
tainty about this projection. But unless all the economic models and all
the climate models are dead wrong, the pace of global warming will
quicken over the decades to come and climate conditions will quickly
pass beyond the range of recent historical experience.
