|Review of revised manuscript: “Objective extraction and analysis of statistical features of Dansgaard-Oeschger events”|
First, I want to apologize to the authors for the time it has taken to complete this review. I was away on vacation and for scientific meetings.
Below is a list of some of the changes that I think are necessary for publication – all of which were already in my first review. The authors take a different view on what the words “control” and “determine” mean than I do. The majority of readers will be interested in DO climate dynamics and physics rather than statistics, and so these words need to be changed to bring them into alignment with how the majority of readers would understand them.
The authors still confuse causation with correlation. In the old manuscript they claim that cooling rates “control” the interstadial durations – in reality they are merely correlated. In the revised manuscript they have simply changed the word “control” into “govern”. This is unacceptable. Simply changing a word does not solve the underlying scientific fallacy. There is no mechanistic link given by which cooling rates control/govern the interstadial duration. More likely, both are controlled by a third parameter. The authors concede this point. This must be corrected, because both words imply (mechanistic) causality, which is not proven or even made plausible. The authors suggest that their words must be interpreted in a statistical context. I am note entirely sure what that means, but to the majority of readers this will not be how they interpret the word “govern”.
The authors maintain that it is conceivable that the interstadial duration is “determined” hundreds to thousands of years ahead of time. The correct word here is “can be predicted”. They give an example of walking towards a town at a fixed rate. My arrival time can be predicted once my speed is known, but it is not yet “determined”. I could decide to take a 1 hour coffee break. The outcome of a democratic election can be *predicted* by polling the voters, it is not yet *determined* by this process. Likewise, once several hundred years have elapsed within an interstadial, the cooling rate can be estimated reliably, which means the duration of that interstadial can be *predicted* because the cooling rate is *correlated* with the duration (it does *not* control/govern it). This does not mean that the duration is already determined – volcanic eruptions, ice shelf collapse, or any number of things could happen that influence the true duration.
The discussion section is still just a summary of the work, now with a single paragraph of true discussion added (last one). This is not the function of a discussion section.
The authors have not attempted to shorten the paper. I still think this is appropriate, but I’ll leave this up to the editor.
Data availability. The authors are not compliant with the CP data policy, which states that “Copernicus Publications requests depositing data that correspond to journal articles in reliable (public) data repositories, assigning digital object identifiers, and properly citing data sets as individual contributions.” The 5yr data series should be publicly archived in a long-term database. These data have been used in several papers now, and requiring readers to contact a colleague of the authors (who is close to retirement age and not known for his reliability in responding to email) is not an acceptable form of archiving.