2.2.3 Climate Change
According to the 1995 Scientific Assessment Report of the
Intergovernmental Panel on Climate Change (IPCC), “The body of statistical
evidence now points towards a discernible human influence on global
climate.” This influence is due to the increase in atmospheric
concentrations of greenhouse gases since pre-industrial times, and the effect of
this increase on the energy balance of the Earth.
It is now the view of the IPCC that continued increases in
greenhouse gas concentrations, as a result of human activity, will lead to
significant climate change (enhanced global warming) in the coming century.
However, uncertainties still exist limiting our ability to quantify human
influence and project the future. Nevertheless, it appears that major changes
are required in current fossil-fuel-based energy consumption patterns. This is
because business-as-usual is likely to increase carbon emissions by a factor of
three by 2100, whereas according to the IPCC, emissions will have to fall far
below the present level in order to stabilise the atmospheric concentration of
carbon dioxide (CO2).
Earlier IPCC findings spurred governments to sign the United
Nations Framework Convention on Climate Change (FCCC) in Rio (1992). Since 1994,
the UNFCCC has now been ratified by more than four-fifths of the UN member
states (164 as of end of 1996). The UNFCCC involves voluntary, rather than
binding, emission stabilisation commitments. Targets and timetables for emission
reductions are now being negotiated. Inventories of human-related emissions of
CO, (1990-1995 and 2000 projections) have shown that most industrialised
countries will not, in fact, meet their voluntary target of limiting their year
2000 emissions to 1990 levels.
The threat of climate change is principally an energy-related
problem. Current energy systems are based on the combustion of fossil fuels
which account for 76% of the world’s primary energy. This combustion leads
to about three-fourths of the annual human-related emissions of the main
greenhouse gas CO2. These annual emissions accumulate, increasing the
greenhouse gas concentrations in the atmosphere. Even taking into account the
quantitative uncertainties, current energy patterns are leading the world down a
path that is unsustainable by threatening the global climate. This is the
energy-climate change
nexus.
