2.2. Carbon footprint method
The concept of sustainable development gained worldwide
recognition in 1992 at the World Environment and Development
Conference, during which many research methods for the measurement
of sustainable development were presented. Among these
methods, the ecological footprint method has been widely accepted
and used. TheWorld Wide Fund for Nature stated in the 2008 Earth
life report that half of the overall ecological footprint can attributed
to the carbon footprint of human activities (World Wide Fund for
Nature, 2008). The carbon footprint method is an ecological footprint
approach that takes an ecological perspective in reflecting the
energy consumption of humans, particularly energy from fossil
fuels (Energy Information Administration, 2009; Tukker and
Jansen, 2006). Carbon footprint is defined as the forest area
required to absorb a certain amount of CO2 emitted from human
activities under certain technical conditions.