Figure 1-1: Climate change-
an integrated framework. Schematic and simplified representation of an
integrated assessment framework for considering anthropogenic climate change.
The yellow arrows show a full clockwise cycle of cause and effect among the four
quadrants shown in the figure, while the blue arrow indicates the societal response
to climate change impacts. For both developed and developing countries, each socio-economic
development path explored in the Special Report on Emissions Scenarios
has driving forces which give rise to emissions of greenhouse gases, aerosols,
and precursors -- with carbon dioxide (CO2 ) being the most important.
The greenhouse gas emissions accumulate in the atmosphere, changing concentrations
and disturbing the natural balances, depending on physical processes
such as solar radiation, cloud formation, and rainfall. The aerosols also give
rise to air pollution (e.g., acid rain) that damage human and the natural systems
(not shown). The enhanced greenhouse effect will initiate climate changes
well into the future with associated impacts on the natural and
human systems. There is a possibility of some feedback between the changes
in these systems and the climate (not shown), such as albedo effects from changing
land use, and other, perhaps larger, interactions between the systems and atmospheric
emissions (e.g., effects of changes in land use (again not shown)). These changes
will ultimately have effects on socio-economic development paths. The development
paths also have direct effects on the natural systems (shown by the anti-clockwise
arrow from the development box) such as changes in land use leading to deforestation.
This figure illustrates that the various dimensions of the climate change issue
exist in a dynamic cycle, characterized by significant time delays. Both emissions
and impacts, for example, are linked in complex ways to underlying socio-economic
and technological development paths. A major contribution of the TAR has been
to explicitly consider the bottom righthand domain (shown as a rectangle) by examining
the relationships between greenhouse gas emissions and development paths (in SRES),
and by assessing preliminary work on the linkage between adaptation, mitigation,
and development paths (WGII and
WGIII). However, the TAR does
not achieve a fully integrated assessment of climate change, since not all components
of the cycle were able to be linked dynamically. Adaptation and mitigation are
shown as modifying the effects shown in the figure.
