General comments

The authors present two datasets describing the occurrence of munition piles and their spatial distribution in relation to maritime activities. Dataset A is publicly available. However, within the manuscript, a non-public link is cited, while the publicly accessible link is provided only in the Data Availability section. This inconsistency should be harmonized (see also specific comments).

Dataset B, which represents a subset analyzed in greater detail, is not yet accessible. Consequently, statements based on this dataset cannot be reviewed properly.

Overall, the manuscript is understandable and methods are described in great detail, aside from minor issues (see specific comments).

Specific comments

Chapter 1:

• Please define the term living dataset.
• What do you understand under the term munition properties? Please define in more detail.
• When is a pile a pile? How do you define that an object is belonging to a pile and when do you characterize it as scattered object, respectively? For example, is number of objects or the distance of the objects relevant to define a pile?
• As source for Dataset A is given Frey et al. 2026a. This reference is not public available. At the end of the manuscript you refer to Pangaea. I guess it’s the same dataset? Use this reference also in chapter 1.

Chapter 3: Which area is covered by MBES data. Please highlight in Figure 2. Including Lübeck Bay. See also comment for Figure 2.

Chapter 3.1: The Authors refer the description of the dump sites to other publications. Nevertheless, a short summary would be good.

Chapter 3.1.2, line 181: please spell out the term OFOP.

Chapter 3.2, line 210: Frey et al. 2026b is reference not public available. In my opinion, this is critical because details about the data origin are important information.

Chapter 3.2, line 211 f: I’m wondering which parameter are discussed in this manuscript. Please elaborate. I guess the authors describe this later. However, here the reader is left in the dark.

Chapter 3.2, line 230 f: I guess using ship type depending traffic density from one year is principally ok, but it is not true that 2022 is the only available year. HELCOM provides ship density maps, distinguishing vessel types, since 2006.

Chapter 3.2., line 241 f: The HELCOM data were converged into three categories. Why were these three categories choosen? Why was the category fishing vessels not choosen? I guess fishing activities are more impacted by munition than for example passenger vessels.

Figure 2: It is inconsistent that the maritime activities are only shown for Lübeck Bay and not for Kiel Bay.

Chapter 4.1, line 268 f: By whom or which method have been the munition piles confirmed? Please clarify.

Chapter 4.1, line 293 “In summary, a typical munition pile in the German Baltic Sea …”: There are much more dumping sites in the German Bight (e.g. Mecklenburg Bigth, Pommeranian Bight). Are sure, that these have similar characterized. Otherwise replace German Baltic Sea by “study area”

Figure 3, legend: Number of piles instead of objects?

Chapter 5, line 401 f: replace German Baltic Sea by study area (see comment above)

Chapter 5, line 409: The historical data don’t match with this study. Summarize shortly why.

Technical corrections

Values and units are not consistently separated from one another. Some are separated by spaces, while others are not.

Thousands separators are not used consistently

This manuscript presents a comprehensive, well-documented, and highly valuable dataset on munition piles in the German Baltic Sea. The methodology is clearly documented, the data products are of high quality, and the manuscript is well structured and easy to follow. The dataset will be of considerable interest to researchers, environmental managers, and maritime stakeholders concerned with underwater munitions, environmental monitoring, and marine spatial planning.

The manuscript represents a significant contribution to the availability of high-quality marine environmental data and provides an important basis for future research and management activities in the Baltic Sea region.

I consider the manuscript to be scientifically sound and suitable for publication in ESSD. Only technical clarifications and editorial improvements may be considered during the final revision process.