The Influence of the Atlantic Multidecadal Oscillation on the Choco Low-Level Jet and Precipitation in Colombia

Round 1

Reviewer 1 Report

This study analyzed the effects of Atlantic Multidecadal Oscillation (AMO) that may turn the strength of the Choco Low-Level Jet(CJ) after 1997, which in turn led to climate variability changes in rainfall over Colombia. The authors point out that Sea Surface Temperature(SST) anomaly pattern intensifies the inter-basin equatorial gradient between the Atlantic and eastern Pacific leading to the strengthening of CJ under the background of warm AMO and cold Pacific Decadal Oscillation (PDO). Since 1997, the strengthening of CJ has increased precipitation in the North and Central Pacific region of Colombia(NCP). The manuscript can be improved a lot through careful revision. All figures of the manuscript are in low resolution. Thus, I would recommend a Major revision. Major comments: 1.The clarity of all figures is a little bit low, which greatly affects the readability of the article. Please update these figures. 2.It is suggested to add the time series of PDO and AMO so that readers can understand the relationship between the decadal changes of SST and CJ. Minor comments: 1.In figure 1, it is convenient for readers to understand the physical mechanism between jet stream and local precipitation by adding some arrows shape to indicate where the CJ and Caribbean Low-Level Jet (CLLJ) are. 2.In figure 7a, the arrows are a little lighter and the “divergent flow” mentioned in page 11 line 318 doesn't look very clear. Please address the issue. 3.Page 5 line 185, please correct the “th50”. 4.Page 6 from line 207 to line 209, the format is confusing. Please reframe this passage.

Author Response

We would like to thank the reviewer for his/her helpful comments. Please, you will find below our point-by-point responses (in the attached document).

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper presents an interesting study to understand the impacts of AMO and PDO on the low-frequency CJ variation, La Nina events and thus impacting the precipitation patterns on Colombia. I think the paper has potential and quality-wise can to be improved significantly. My comments –

The analysis is mainly focused on the selected range of data from a period of 1983-2016. To attain any statistically significant outcomes, I think the data are insufficient. Can you provide a justification for the selection of the present dataset? Most of the work presented is already found elsewhere in another context, Please highlight the novel/original contribution of this work? What is the research methodology, it seems that the research methodology used is generic involving some basic graphical analysis of the standard atmospheric-climatic dataset. Observations from graphs are mainly used to claim association/influence/Causation in patters. Can you apply quantitative approaches for mathematically/statistically establishing these observed associations? I noted at several occasion information is repeated. For example, in section 3 from Line 212 – 225, then in the conclusion section line 386-481. Information provided (line 201-209) on student t-test is basic textbook information and could be referenced. Analysis of SON time series using three homogeneity tests should be moved in result sections. Some justification needed on the selection of the homogeneity test along with some description of the method and comments on the analysis outcomes.

Author Response

We would like to thank the reviewer for his/her helpful comments. Please, you will find below our point-by-point responses (in the attached document).

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have addressed all my concerns.