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
SPM-691 A 11:13 11:15 According to footnote 4, the uncertainty ranges refer to 90% confidence intervals. According to footnote 5, a 90% likelihood
is exactly the threshold that separates "likely" from "very likely" statements. Hence, it would be equally correct to say that the
true value of a variable is "likely" or "very likely" within a 90% confidence interval. The text uses the term "likely" in this
case. In order to avoid the subjective (but potentially important) decision which of the two verbal expressions to use, the
vague term "likely range" should be replaced by the exact term "90% confidence interval".
[Govt. of European Community (Reviewer’s comment ID #: 2008-18)]
SPM-692 A 11:13 11:13 As above. (What is the meaning of "Best-estimate" here? - TSU Edit)
[Govt. of Italy (Reviewer’s comment ID #: 2012-47)]
SPM-693 A 11:14 11:15 Please summarize the range of estimates in one short sentence such as: "IPCC scenarios indicate a likely global warming of 2-
4 degrees C towards the end of the 20th century".
[Govt. of Denmark (Reviewer’s comment ID #: 2007-18)]
SPM-694 A 11:14 11:15 Please specify how these uncertainty range compare to the ranges given in TAR, i.e. 2-sigma vs. 1.65-sigma (see chapter 10).
[Govt. of Denmark (Reviewer’s comment ID #: 2007-21)]
SPM-695 A 11:14 11:15 The fact that the temperature changes given for the A1T and B2 scenarios are the same, while the footnote on the previous
page (SPM-10) gives the approximate CO2 equivalents of these scenarios as 700 and 800 ppm respectively, will appear
inconsistent to a reader. If these figures are retained (and I can't find the reference in the body of the report to check their
accuracy) some clarification could possibly be given in the box describing the scenarios at the end of the SPM.
[Govt. of New Zealand (Reviewer’s comment ID #: 2015-7)]
SPM-696 A 11:14 11:15 Reduce the number of figures in this bullet point e.g. just give the best estimates and then the full range for all scenarios
together. Alternatively the full range could be given in a table or an figure.
[Govt. of Norway (Reviewer’s comment ID #: 2016-53)]
SPM-697 A 11:14 11:15 Present these values in a table together with the values below in page 11 lines 24 to 26
[Govt. of Switzerland (Reviewer’s comment ID #: 2020-26)]
SPM-698 A 11:16 11:16 The projections of climate change presented in the SPM are predominately about global averages. Policymakers also have a
strong interest in regional effects - notably in their own regions. We propose adding another dot point on projected regional
temperature changes, which could be based upon the TS at page 42 lines 37-40.
[Govt. of Australia (Reviewer’s comment ID #: 2002-105)]
SPM-699 A 11:17 11:21 Are carbon dioxide feedbacks incorporated in the ranges presented in the preceding paragraph or not? Is the 1 degree in
addition to the 3.2 making it 4.2 with c-cycle feedbacks? Be clear. Also, why is the result for A2 only given here? Perhaps it
would help if this paragraph began with a statement explaining to the reader that there are, at present, only a few fully coupled
carbon cycle-climate models and therefore the magnitude of this feedback is uncertain but known/expected to be positive (as
explained in the existing first sentence and SPM-13 line 30).
[Govt. of Canada (Reviewer’s comment ID #: 2004-50)]
SPM-700 A 11:17 11:17 The term "uptake" should be changed in "net uptake" since it is related to the net flux of the biosphere or the oceans, that is
the sum of uptake (photosyntesis) and respiration
[Govt. of Italy (Reviewer’s comment ID #: 2012-5)]
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