This special issue reviews technological options for mitigating carbon dioxide (CO2) emissions. The options analyzed include efficiency improvements, renewable energies, clean fossil and zero-carbon energy technologies, carbon sequestration and disposal, enhancement of natural carbon sinks...

Humans spend, on average, a constant fraction of their time and expenditure on travel. These and a few other constraints allow a new model for projecting regional and world travel, which we use to develop a scenario for carbon emissions from passenger transport. Globally, carbon emissions rise...