Government Comments on the Final Draft of the SPM IPCC Working ...

<strong>Government</strong> <strong>Comments</strong> on the Final Draft of the SPM
IPCC Working Group I Fourth Assessment Report
Batch
Page:line
No.
From To Comment
[Govt. of France (Reviewer’s comment ID #: 2010-38)]
SPM-598 A 10:12 10:13 It would be of assistance if the authors could ascribe a "likelihood" reading to qualify their statement that "values substantially
higher than 4.5C cannot be ruled out" (i.e. is it "very unlikely" that values substantially higher than 4.5C would occur?)
[Govt. of Australia (Reviewer’s comment ID #: 2002-96)]
SPM-599 A 10:13 10:13 Based on Chapter 9, page 9-64, a better explanation of the likelihoods of values below 1.5C and above 4.5C is needed,
particularly since the likelihoods are described as being different. Yet, as currently written, use of phrase "cannot be excluded"
suggests that values above 4.5 might be even less likely than values below 1.5, which have been determined to be "very
unlikely". A better description of the probability distribution of projections would help clarify the corresponding likelihoods
of the higher and lower values.
[Govt. of Canada (Reviewer’s comment ID #: 2004-40)]
SPM-600 A 10:13 10:13 ".., but agreement of models with observations.." I think this is confusing to a policy maker since we are talking about future
projections. Maybe a simpler statement could be formulated.
[Govt. of Italy (Reviewer’s comment ID #: 2012-14)]
SPM-601 A 10:13 10:13 Replace ‘but ...... values.’ by ‘but models with such a high sensitivity are less successful in simulating the past..‘
[Govt. of Netherlands (Reviewer’s comment ID #: 2014-29)]
SPM-602 A 10:13 10:15 Replace ‘Water vapour .... uncertainty.‘ by ‘Water vapour changes are now better understood than in the TAR and are likely
to produce a dominant positive feedback to the climate sensitivity. Cloud feedbacks remain the largest source of uncertainty.’
[Govt. of Netherlands (Reviewer’s comment ID #: 2014-30)]
SPM-603 A 10:13 10:13 Add “of past climate” after “observations” (line 13)
[Govt. of United States of America (Reviewer’s comment ID #: 2023-65)]
SPM-604 A 10:13 10:16 How can it be known for sure that water vapor feedbacks are the dominant ones when there is still uncertainty in cloud
feedbacks, especially since there are links between the two?
[Govt. of United States of America (Reviewer’s comment ID #: 2023-66)]
SPM-605 A 10:18 10:18 It is unclear why the authors changed the word "substantial" which appears in the text of Chapter 9 and the TS, to
"significant". Suggest reversion to "substantial".
[Govt. of Australia (Reviewer’s comment ID #: 2002-97)]
SPM-606 A 10:18 10:19 The double negative in the phrasing of the first sentence is difficult to understand ("….were not due to unforced variability
alone"). Can this be put into positive language?
[Govt. of Australia (Reviewer’s comment ID #: 2002-98)]
SPM-607 A 10:18 10:19 It is a very confusing sentence. "at least the seven centuries prior to 1950" need some supports from paleoclimate record.
Again, "unforced variability alone" is difficult to understand.
[Govt. of China (Reviewer’s comment ID #: 2006-31)]
SPM-608 A 10:18 10:19 This sentence is very hard to understand due to the double negation. It should be rephrased without double negation, e.g. by
changing "very likely" to "very unlikely" and deleting "not".
[Govt. of European Community (Reviewer’s comment ID #: 2008-15)]
SPM-609 A 10:18 10:19 Same comment on the definition of "unforced variability" as for page 8 lines 14 sqq.
Page 64 of 99