life expectancy essays

life expectancy essays The environmentalist view of the energy intensity is based on the legacy of the I = PÃâ€"AÃâ€"T equation in which environmental Impact equals Population, multiplied by Affluence, and further multiplied by Technology (Earth Report 2000: Revisiting the True State of the Planet. 1999). The further desegregation of this formula implies that energy intensity can be looked upon as an integrative variable describing the impact of both technology and affluence. Bruce et al. (1996) argue that intensity is inversely related to efficiency. Improving efficiency reduces the amount of energy required to provide a given output, i.e. an output of the same quality and quantity. In real life, though, the precise nature of the output is unknown, hence intensity is a proxy for efficiency. The Kaya Identity is an expression that is introduced by Bruce et al. (1996) to describe the relationship among the factors that influence trends in energy-related carbon emissions: C = (C E) Ãâ€" (E GDP) Ãâ€" (GDP POP) Ãâ€" POP. The formula links total energy-related carbon emissions (C) to energy (E), the level of economic activity as measured by Gross Domestic Product (GDP), and population size (POP). The first two components on the right-hand side represent the carbon intensity of energy supply (C/E) and the energy intensity of economic activity (E/GDP). Economic growth is viewed from the perspective of changes in output per capita (GDP/POP). At any point in time, the level of energy-related carbon emissions can be seen as the product of the four Kaya Identity components - energy intensity, carbon intensity, output per capita, and population size. In fact, growth in energy intensity in industrialized countries has historically lagged behind economic growth, whereas the two are more closely correlated in developing countries. As a country's energy intensity changes, so does the influence of a given level of economic activity on carbon emissions. Increased energy use and ...