SODBatch A&B SPM Comments co-chair response final ... - ipcc-wg3

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Comments
IPCC WGIII Fourth Assessment Report, Second Order Draft
to to equity considerations – it is merely a statement about where
efficient reductions can occur based on existing studies.
It is extremely surprising that for several reasons that the range of
potential mitigation opportunities at given costs is so narrow (8 to
12Gt CO2-eq at US $20 and 18 to 25 Gt at US $100. First, one
would imagine that “economic reduction potential” would be very
sensitive to the price of fossil fuels, which are highly uncertain – it
has to matter whether oil is $20 per barrel or $100 per barrel.
Second, the state and cost of available technology in 2030 is
unknown. Third, the evaluation of “non market costs and (nonclimate)
benefits” that is apparently included in the calculation are
inherently highly speculative, and it is not clear how these costs and
benefits are calculated and whether or not other control measures
are assumed. Fourth, the use of social discount rates is
controversial and should not be buried in a footnote.
3. There should be an explicit reference, in the text, to the fact that
“economic reduction potential” is generally less than “market
reduction potential,” the amount of reduction that might be
achieved under private decision making criteria when a market
value is placed on CO2-eq emissions but other institutional and
decision criteria, such as discount rates, are not changed. It is
surprising that for several reasons that the range of potential
mitigation opportunities at given costs is so narrow (8 to 12Gt
CO2-eq at US $20 and 18 to 25 Gt at US $100. First, one would
imagine that “economic reduction potential” would be very
sensitive to the price of fossil fuels, which are highly uncertain – it
has to matter whether oil is $20 per barrel or $100 per barrel.
Second, the state and cost of available technology in 2030 is
unknown. Third, the evaluation of “non market costs and (nonclimate)
benefits” that is apparently included in the calculation are
inherently highly speculative, and it is not clear how these costs and
benefits are calculated and whether or not other control measures
are assumed. Fourth, the use of social discount rates is
controversial and should not be buried in a footnote.
Expert Review of Second-Order-Draft
Confidential, Do Not Cite or Quote
Response suggested by cochairs
is troubling; are we really sure
this is the right definition? (see
also A-658)
Point about mentioning large
potential outside OECD to be
considered
Potential will be shown in
table2 or figure (with more
references to the explanation of
the calculation), and is also
mentioned in sectoral
paragraphs.
Be clear that it is not suggested
to be a political issue
Action
for
chapter
Considerations
by the writing
team
countries are
low, how can
the potential be
high?
On Non-market
benefits:
Included in the
benefits is the
saved cost on
energy, the
other financial
non-climate
benefits are
non-significant.
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