This is an excellent data set with great potential as a valuable contribution to the river plume community. My general comment is there is a lot going on in this manuscript: the figures are busy, and there are many redundancies. I find myself often losing track of what is important and what is extra “fluff”. It think the results, discussion, and associated figures can be streamlined and the story made clearer. I am generally fine with the analysis, but some relatively significant restructuring and rewriting is needed. I outlined my individual and broader concerns in the attached PDF.

-Preston Spicer, PNNL

The manuscript presents field measurements of water-column mean and turbulent statistics during a passing river plume. The topic falls in the scope of the journal Ocean Science. The presentation could be improved to more effectively emphasize the novelty of the study and the science behind these unique measurements. I would recommend publication provided that my suggestions are considered.

Major suggestions:

Introduction: Suggest more explicitly highlighting the novelty of this study. Currently, the authors provided a review of relevant existing studies. Still, it is vague what the knowledge gaps are left in those studies and how this new set of measurements will address any unresolved questions.

Section 4.4: While the Figs. 12 to 16 are adequately described, how each variable is calculated, how its value changes, etc., the implied dynamics and physics are not discussed in detail. Suggest strengthening the discussion. Also, Figures 14 and 15 seem very noisy, and the scattering of the data is not addressed. I suggest the authors improve the clarity of the figures.

Conclusion: Suggest better highlighting the most important findings of the paper. Please also consider discussing possible future work.

Minor suggestions:

Fig. 1(b): what is the variable shown in the image?

Fig. 3(c): The unit of dT/dz is missing.

Fig. 6(c) and Line 220: the vertical current ~ cm/s is quite strong. It also indicates horizontal divergence above the depth of maximum w and convergence below. I would suggest the authors more clearly explain the circulation.

Fig. 8(c): suggest using a different colormap to better highlight positive and negative, for example, lowbluehighred.

Line 262: the sentence is not clear to me. Suggest clarifying.

Line 273: suggest deleting “As presented earlier,”

Fig. 9: what does the purple arrow in Layer 2 mean?

Fig. 10: suggest changing the order of the panels so that panel a is at the top and panel d is at the bottom.

Table 3: in the caption, please define \epsilon_k.

Fig. 14: the unit for K_\{rho} is wrong.