The resultant changes in spatial light patterns indicate socio-economic activities and provide useful information for infrastructure planning, such as expansion of gas and electricity networks. Radiance calibrated lights obtained from night satellite imagery. Table 4-4 summarizes the main quantitative scenario descriptors for each of the four SRES scenario families of the harmonized scenario category. For the scenario family B2, outcomes in terms of cumulative carbon emissions can also be related clearly to scenario characteristics. Equally discernable in Table 4-20 is the wide range in cumulative carbon emissions that characterize the various scenario groups within the A1 scenario family.
Technology can thus be as important a driving force as population and GDP growth combined.
In other words, very different emissions outcomes are possible for future worlds that otherwise share similar developments of main driving forces such as population and economic growth and high rates of technological change. Not surprisingly, differences in quantifications are largest within the A1 balanced technological progress scenario group, which includes the A1B marker scenario. This leads to very wide differences in cumulative emissions, from the Medium Low through to the High categories. Thus, the A2 scenario family also indicates that a wide range of emissions outcomes is possible for any given development path of main scenario driving forces, such as population and income per capita. Both scenarios explore pathways that reduce current income disparities between regions.