While the topic is of significant relevance to the hydrology community, the manuscript in its current form suffers from major shortcomings in clarity, structure, and depth of analysis. The central innovation (dynamic sub-period calibration) is potentially valuable, but is not convincingly demonstrated or critically discussed. The supporting methods (e.g., EDCC) and results are insufficiently explained or buried in supplementary materials, making it difficult to assess the true scientific merit.

I recommend that the authors reconsider the scope and objectives of the manuscript and develop a substantially revised version that clearly communicates the methodology, demonstrates the performance improvements across diverse settings, and meaningfully engages with the implications and limitations of the proposed approach.

Please see the attachment for a more thorough assessment

The paper “A Novel Framework for Calibration and Evaluation of Hydrological Models in Dynamic Catchments” by Lan et al. addresses the important issue of model calibration and proposes a novel framework for calibrating models in so-called "dynamic catchments."

However, in my opinion, the paper suffers from a substantial lack of clarity, an imbalanced presentation of results (with a disproportionate focus on the case study), and omits essential information from the main text.

I recommend that the authors undertake major revisions, reorganize the paper, and include results for all catchments, while shortening the case study analysis. The manuscript should be made clearer and more concise.

Specific Comments:

The authors do not clearly define several key terms foundational to the study, including “dynamic catchments”, “dynamic parameters”, “dynamic features”, “seasonal catchments”, “sub-period” and others. While some meanings can be inferred, proper definitions should be provided in the main paper.

In general, the figures are difficult to interpret. The captions lack sufficient explanation, requiring readers to infer too much on their own.

What are the characteristics of the four selected basins? Why were these basins specifically chosen?

The EDCC (presumably a core procedure in the study) is inadequately explained in the main text. While additional details are provided in the supplementary materials, key components should be moved into the main manuscript for better accessibility.

Is the EDCC applied separately for each basin?

Does the EDCC involve any manual decisions, such as determining the number of clusters? Please clarify.

Is the EDCC applied only during the calibration period? If so, how are its results used in the validation period? Could the method be evaluated using the validation data, for instance by comparing sub-periods defined in the validation period against those from the calibration?

EDCC results are presented only for the four case studies. Statistical summaries for all catchments should be included.

The clustering results should capture more about temporal sequencing. I suggest presenting catchment-wide statistics such as distributions of the number of clusters, sub-period lengths, and other relevant metrics. These would clarify the added complexity introduced by sub-period calibration and should appear in the main paper.