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Detail on CCSP response surface boundaries


When the CO2 levels fall below the lower boundary reported in the CCSP data set for a model, that model's response surface is deemed unable to calculate mitigation costs for that proposal.

Rationale for this approach#

In the case of aggressive climate policies, mitigation costs may rise rapidly for even modest incremental additional emission reductions.

Because of this, it could be highly misleading to extrapolate beyond the lower boundary of the CCSP data set.

As a result, a model's response surface does not report a mitigation cost value if a proposal's CO2 levels fall below that lower boundary.

Interpreting absence of mitigation cost value#

The absence of a mitigation cost value can mean two possible things:

Technical unfeasibility is in a real possibility for proposals that incorporate very aggressive policy prescriptions (e.g. near complete decarbonization of the economy prior to 2050).

Future proposals for modeling mitigation costs#

During the summer of 2010, the Collaboratorium community will work to adopt a new set of mitigation cost models, based on emissions scenarios developed by Stanford's Energy Modeling Forum, that can estimate the costs and/or feasibility of more aggressive policy prescriptions.