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Targets and timetables
A target is the reduction of a specific percentage of greenhouse gas emissions
from a baseline date (e.g., below 1990 levels) to
be achieved by a set date, or timetable (e.g., 2008 to 2012). For example, under
the Kyoto Protocols formula, the European Union has agreed
to reduce its greenhouse gas emissions by 8% below 1990 levels by the
2008 to 2012 commitment period. These targets and timetables are, in effect,
an emissions cap on the total amount of greenhouse gas emissions
that can be emitted by a country or region in a given time period. See also
quantified emission limitation or reduction commitments.
See interaction effect.
The amount by which it is possible to reduce greenhouse gas emissions
or improve energy efficiency by implementing a technology
or practice that has already been demonstrated. See also economic potential,
market potential, and socio-economic potential.
A piece of equipment or a technique for performing a particular activity.
Technology or performance standard
The broad set of processes that cover the exchange of knowledge, money, and
goods among different stakeholders that lead to the spreading
of technology for adapting to or mitigating climate change.
As a generic concept, the term is used to encompass both diffusion of technologies
and technological co-operation across and within countries.
Tolerable windows approach
These approaches analyse greenhouse gas emissions as they would
be constrained by adopting a long-term climate - rather than greenhouse
gas concentration stabilization - target (e.g., expressed
in terms of temperature or sea level changes or the rate of such changes). The
main objective of these approaches is to evaluate the implications of such long-term
targets for short- or medium-term tolerable ranges of global greenhouse
gas emissions. Also referred to as safe landing approaches.
The terms top-down and bottom-up are shorthand for aggregate
and disaggregated models. The top-down label derives from how modellers applied
macroeconomic theory and econometric techniques to historical data on consumption,
prices, incomes, and factor costs to model final demand for goods and services,
and supply from main sectors, like the energy sector, transportation, agriculture,
and industry. Therefore, top-down models evaluate the system from aggregate
economic variables, as compared to bottom-up models that consider
technological options or project specific climate change mitigation
policies. Some technology data were, however, integrated into
top-down analysis and so the distinction is not that clear-cut.
All items of cost added together. The total cost to society is made up of both
the external cost and the private cost, which together
are defined as social cost.
A minor constituent of the atmosphere. The most important trace gases that contribute
to the greenhouse effect are, inter alia, carbon
dioxide, ozone, methane, nitrous oxide, perfluorocarbons, chlorofluorocarbons,
hydrofluorocarbons, sulphur hexafluoride, methyl chloride, and water
Tradable quota system
See emissions trading.
Economic impacts of changes in the purchasing power of a bundle of exported
goods of a country for bundles of goods imported from its trade partners. Climate
policies change the relative production costs and may change terms of trade
substantially enough to change the ultimate economic balance.
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