chapter - Atmospheric and Oceanic Science

Taking the difference of results (total period annual mean) between the 1%
CO2 increase experiment and the pre-industrial experiment, the configuration is
similar to that in the previous analysis. In that case the difference was performed
between a period of constant high CO2 value and a period of increasing concentration.
Figure 13.12 illustrates the impact. The differences are larger in the Pacific
and Atlantic ITCZ regions; there is an increase of precipitation over the southern
sector of the La Plata basin and part of the Amazon region, and a reduction over the
SACZ area. The patterns are similar to other model results.
c. Climate of twenty century
Regional climatic scenarios
Fig. 13.11. Difference between period I (year 71 to year 280) and period II (year 11 to year 70) of 1% CO2
increase experiment. (a) Mean annual precipitation (%); (b) Mean annual temperature (ºC).
This experiment is running from 1861 to 2000, and contains all anthropogenic
forcings during the period. The objective of this experiment is to establish one of
the controls run to compare with future climates. The difference of this run with the
1% CO2 increase experiment is shown in figure 13.13. Results are similar to the
previous comparisons, with increased precipitation over the La Plata basin and
increased temperature mainly over central South America.
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