Comment on essd-2021-49

I miss the very important information about the timescale. L15: I think it would improve the readability when first the water bodies and then the areas would be explained. However, you also could mention that you measured stable water isotopes earlier in the abstract. L20: maybe use the term stable WATER isotopes here. Make sure to use one term consistently in your text. Later you used the term stable water isotopes, too. L20: please define roughly which meteorological and hydrological data is connected to your data set. Additionally, no meteorological or hydrological data are found in the data files. L34: use D or H consistent in your paper, please L37: please generally check your citation style! Sometimes the ";" symbols are weird looking sometimes there are too many symbols e. g. L47 L37ff: I would be nice to see some more specific examples which can be related to the data presented here. Moreover, I am missing completely a critical view on the usage of stable water isotopes and their uncertainties here. E. g. unintended fractioning processes as well as troubles due to measurement methods! L47: Christophe is a first name! Also, this article is about oceans I am not sure how well this fits your paper. L47: I could find the article of Zhang et al., 2015 only in non-English language. Please provide another link in the bibliography or provide further information L51-L52: I think other more important paper would suit this sentence much better! Also, Metthew is a first name! L62: I think that this should be much more critical! There are many drawback and uncertainties using stable water isotopes which should be at least briefly mentioned. See: Poca et. al 2019 (doi: 10.1007/s11104-019-04139-1); von Freyberg (doi: 10.1111/2041-210X.13461) and many more! L80: change ues to use, please L76 ff: This is very similar to the abstract. I miss your motivation for the study and why the data of this specific region is important. In the abstract you mention something about ecological importance etc. L93: what do the coordinate show / mean? L94: numbers such as average discharge in m3/s would be more helpful, I think. If seasonality is important, show average values from summer / winter or dry / rain season L96 what does average annual temperature below 6 C mean? L126: rain collection is slightly unclear to me. How did you store the water to prevent evaporation before measurement? This would be crucial to know for further discussion of data quality and possible uncertainties. L149 bold! L150 unclear where soils samples are taken. What does "sequentially at 10 cm intervals" mean? L155 a new paragraph would fit here L155 did you use branches / twigs or stem xylem? How much (better in gram instead of a volume). Which tree species (conifers / hardwood)? Here, a lot of important information is missing! L164: I think the abbreviations are everything else but "easy to understand and use". I would prefer abbreviation which include somehow sampling type (i. e. river, precipitation, soil) and the site L168: the corresponding "weather station file" was not found in the data set. Also, should have multiple sampling types not have the same abbreviation in case someone will merge the different data sets. L197-L198: please, define what did you do with the software for data quality check. L205 very unclear L213: you mention that you should not "select the wrong samples". How do you define "wrong samples"? L247: I think that information about the water level are not of interested here. Discharge data would be more interesting to give the reader an idea about the river properties. L286 I guess this conclusion is not fitting well since you would not expect soil water to be recharged by plant water L293 What does 4.4 reference to? L294 what do these numbers mean? Unit? L317 the outlook is missing or it is at least very short Figure. 1: It is unclear whether north is on top of the maps; Big map: It is hard to find point b and point a is hardly visible. The scale of elevation shows very random numbers. Subfigures a to h are too small to read anything! On subfigure d I would expect the river to "flow in" on the "bottom" and "flow out" on the top according to the bigger map. However, the river is only half way through the map. Subfigure g is random and not understandable. You never mention subfigure g in the text. Table 1: the table is missing an appropriate caption. As well, the units are not clear. i. e. precipitation mm/ year? Additionally, in the study site description you mention annual precipitation of max. 600mm, however, according to your table one site received 1040mm (I guess per year) Same for temperature: air or water temperature? Figure 3: which water bodies / soil water sites are presented here? Powered by TCPDF (www.tcpdf.org)

It is a rich and valuable source. Now the research can start on areas where sea level indicators are there but as yet not well or controversially dated. This compilation will definitely revitalize the discussion about the Last Interglacial in the Mediterranean -all the more since the MISS 5.5 deposits and terraces are very good indicators for neotectonics (see below).

Specific comments:
(1) You seem to have made use only of texts in English, French and Italian. Unfortunately, the important PhD theses of Brückner (1980)* and Radtke (1983)** -in German -are missing. Please see also more references I added to the bibliography.
*flight of 11 marine terraces bordering the Gulf of Taranto, southern Italy, including the MIS 5 terraces (this is well summarized in the "TARANTO -IGCP 639 Field Guide", STOP 3, which I attach.
**marine terraces of central Italy at the Tyrrhenian Sea, including the MIS 5 terraces (2) You rightly replaced Strombus bubonius by Persistrombus latus. Why not also replace MIS 5e by MIS 5.5.? This makes more sense than the combination of numbers and letters (also: MIS 5c = MIS 5.3; MIS 5a = MIS 5.1). First time you mention MIS 5.5 is in line 777, next time in line 1039.
(3) You could mention in this text that the MIS 5.5 terrace or MIS 5.5 deposits are excellent indicators for neotectonic movements -even if this has already been mentioned elsewhere. This makes your research even more valuable. When the MIS 5.5 terrace is at an elevation higher than 10 meters, this definitely indicates a long-term uplift trend of the region (e.g., southern Calabria). When the MIS 5.5 terrace is missing it may have been eroded or it is submerged (e.g., Dalmatian coast).
(4) The transgression peak is a sea level indicator, not a good one, but it shows the farthest inland expansion and the uppermost limit of the 5.5 terrace.
(5) You systematically combine maps with location of the sites with a lower panel in which the altitudes of the MIS 5 terraces are visualized (starting with figures 8, 9, 11 etc.). You should repeat the numbers of the sites in the map also in the lower panel, so that the link between map and panel is clear (in cases, where sites cluster, the assignment is unclear).
(6) Table 1: These descriptions/definitions should definitely (!) be supported by cartoons visualizing what you mean. A good cartoon/figure says more than many words! (7) Since this is so fundamental for your article you should dedicate a paragraph to what is understood by MIS 5e = MIS 5.5 (definition; time span; a graph showing the MIS 5.5 peak and the subpeaks of MIS 5.3 and MIS 5.1), show a curve with the MIS 5 record and the MIS 5 sea-level fluctuations.
(8) See also some references added to the bibliography.
(9) See also my comments on the PDF of the text.

General remark concerning language and orthography
The text should be edited/polished by a native speaker. Just a few remarks from my side: -In English there is no comma before "that".
-"et al.", dot after "al"; abbreviation from "alii" -names of biological species in italic letter, but not "sp." -there should be a spacing between the number and the dimension (e.g.: "28 m").