Other Climate Changes

There are a variety of other climate changes that might be expected to occur simultaneously with changes in temperature. These include changes in precipitation, an increase in the mean sea level, and more variability in the climate. As discussed in detail in IPCC (1996), changes in precipitation patterns and cloudiness have been noted over the past approximately four decades and there is evidence that the sea level has risen by 10-25 cm. The IPCC document should be consulted for detailed evidence for these effects and their possible relationship to anthropogenic perturbations. 

As seen throughout this chapter, the parameters controlling climate are extremely varied and complex, 

FIGURE 14.63 Calculated temperature changes relative to 1990 for existing policies (—), for a 5% decrease in equivalent C02 as required by Kyoto protocol from 1990 to 2010 followed by no further emissions reductions ( ), and for further reductions of 1% per year (compounded) from 2010 to 2100 (---) assuming a climate sensitiv- 

Nevertheless, the balance of evidence suggests that there 

Elucidating this influence remains a challenge for the twenty-first century. 

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In closure we note that here we have only discussed the impact of a change of the rate of SLR on coastline evolution and not the impacts associated with other climate change driven impacts such changes in regional hurricane or typhoon climates, changes in dominant wave direction, storm frequency and intensity, and ENSO, NAOs, and SOI oscillations (cf. the chapter by Komar et al. and Ref. 43), which may have local and/or regional impacts as important as or even exceeding the impact due to SLR alone. 

Unlike Albert Einstein s E = mc, for example, the theoi y of human-driven climate change is not a singular theoi y but consists of several interlocking theories, some better defined chan others. 

Reduced risk of harm through famine avoidance Reduced risk of harm through disease prevention Reduction in other proposed climate change hazards Reduced risk of harm through avoided economic impacts of climate change NONE NONE NONE NONE... 

Concerns about global climate change have led to extensive research and high-level international debates about the need for targets and timetables to reduce carbon dioxide emissions. Some policymakers believe that current uncertainties in how to approach the issue do notjustify an all-out effort to reduce carbon dioxide emission, while others feel that this is a crisis needing immediate attention. 

Figure 3. Feedbacks in terrestrial ecosystem responses to C02-induced climate change. Arrows with plus signs (-I-) indicate processes that have positive effects or that increase the rates of other processes. Arrows with minus signs (—) indicate processes that have the opposite effects.

It seems unlikely that feedbacks due to species replacement have begun since the beginning of the Mauna Loa record because compositional changes due to climate change will take decades and have not yet been documented on a wide scale. However, this fact increases the importance of such feedbacks to future trends in atmospheric CO2 when these feedbacks become important it is highly unlikely that positive and negative feedbacks will exactly cancel each other and more likely that one or the other will prevail and cause deviations from current trends in atmospheric CO2. 

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