Figure 2-11: Schematic
illustration of SRES scenarios. The four scenario “families” are shown,
very simplistically, for illustrative purposes, as branches of a two-dimensional
tree. The two dimensions shown indicate global and regional scenario orientation,
and development and environmental orientation, respectively. In reality, the four
scenarios share a space of a much higher dimensionality given the numerous driving
forces and other assumptions needed to define any given scenario in a particular
modelling approach. The schematic diagram illustrates that the scenarios build
on the main driving forces of GHG emissions. Each scenario family is based on
a common specification of some of the main driving forces.
