Emissions/Data uncertainties limitations: Difference between revisions

From IMAGE
Jump to navigation Jump to search
m (Text replace - "CO2 " to "CO<sub>2</sub>")
m (Text replace - "CO<sub>2</sub>" to "CO<sub>2</sub> ")
Line 6: Line 6:


===Uncertainties===
===Uncertainties===
EDGAR data on activities and emission factors need to be aggregated in order to be used in IMAGE. In this process, decisions need to be made (e.g., on the use of weighted averages and representative sectors), which lead to additional uncertainties. In general terms there are three levels of uncertainty. For energy and industry, emission factors for CO<sub>2</sub>are less uncertain than those for non-CO<sub>2</sub>emissions. In turn, the uncertainty in emission factors for land use and natural sources is larger than for energy and industry sources because of the extreme variability of the factors controlling processes in space and time.
EDGAR data on activities and emission factors need to be aggregated in order to be used in IMAGE. In this process, decisions need to be made (e.g., on the use of weighted averages and representative sectors), which lead to additional uncertainties. In general terms there are three levels of uncertainty. For energy and industry, emission factors for CO<sub>2</sub> are less uncertain than those for non-CO<sub>2</sub> emissions. In turn, the uncertainty in emission factors for land use and natural sources is larger than for energy and industry sources because of the extreme variability of the factors controlling processes in space and time.


Future emissions and their uncertainty depend on the activity levels determined by other IMAGE components, and on the emission factors. Estimations of future emission factors in the energy and industry systems, described above, rely on historical observations and learning curves. However, future legislation and effective implementation may influence these factors more, and more abruptly. Emission factors for land-use activities may change in the future, also in the absence of climate policy, but are assumed to be constant because of lack of data. As the future development of emission factors is per definition uncertain, the influence is explored by changing the emission factors for different storyline-based scenarios.  
Future emissions and their uncertainty depend on the activity levels determined by other IMAGE components, and on the emission factors. Estimations of future emission factors in the energy and industry systems, described above, rely on historical observations and learning curves. However, future legislation and effective implementation may influence these factors more, and more abruptly. Emission factors for land-use activities may change in the future, also in the absence of climate policy, but are assumed to be constant because of lack of data. As the future development of emission factors is per definition uncertain, the influence is explored by changing the emission factors for different storyline-based scenarios.  


===Limitations ===
===Limitations ===
IMAGE covers almost all emission sources and gases within a consistent framework, based on a few international data sets and authoritative sources. However, some specific emissions are only included as a group, without the underlying production processes. Even more importantly, IMAGE does not include emissions from peat and peat fires, although they constitute an important source of air pollutants and CO<sub>2</sub>emissions ([[IPCC, 2007a]]).
IMAGE covers almost all emission sources and gases within a consistent framework, based on a few international data sets and authoritative sources. However, some specific emissions are only included as a group, without the underlying production processes. Even more importantly, IMAGE does not include emissions from peat and peat fires, although they constitute an important source of air pollutants and CO<sub>2</sub> emissions ([[IPCC, 2007a]]).
}}
}}

Revision as of 10:30, 1 July 2014

Emission module of IMAGE 3.0
Flowchart Emissions. See also the Input/Output Table on the introduction page. Anthropogenic sources, for natural sources see Table 5.2.2. More detail on inputs and outputs, and how they link to other IMAGE components is presented at the end of this section (Emission table).