Geoscience Reference
In-Depth Information
13
DEALING WITH CLIMATE CHANGE:
ADAPTATION AND GEOENGINEERING
Earlier chapters explained how uncontrolled growth in carbon dioxide
emissions and other gases is leading to vast changes in our climate sys-
tems along with human and natural systems. Most changes are likely
to happen gradually, like a long freight train gathering speed and mo-
mentum. We cannot predict the impacts with precision, but they are
unwelcome at best and dangerous at worst. And like the accelerating
freight train, they will be hard to stop once they get under way.
The chapters in this part consider steps to deal with the threat of
climate change. There are three major approaches. A fi rst approach is
adaptation, which involves learning to cope with a warmer world rather
than trying to prevent it. Relying only on adaptation is favored by those
who oppose taking costly steps to slow climate change as well as those
who believe that the effects of warming are likely to be small, but adap-
tation will be part of any portfolio of strategies.
A second approach is geoengineering, which would offset the CO
2
-
induced warming by introducing cooling elements. Geoengineering is
likely to be at least partially effective but is unproven and may have
dangerous side effects.
The third approach, often called mitigation, consists of actions to re-
duce emissions and atmospheric concentrations of CO
2
and other green-
house gases. Mitigation has been the focus of international negotiations
and is the safest solution from an environmental standpoint. It is also
the most expensive in the short run and therefore the most diffi cult to
achieve.
