**5. Conclusions**

This study combined satellite images and InSAR data to examine the interplay of vertical land motion (VLM) (2007–2021) and coastline changes (2010–2020) along a deltaic barrier in the Colombian Caribbean. The findings are as follows:

• Annual coastal erosion rates increase in the same direction as the littoral drift (i.e., East-West direction), reaching a peak of −25 m/yr next to a lagoon known as Cuatro Bocas. In contrast, VLM patterns are highly variable along the study site, precluding linking coastal erosion rates to negative VLM values in general.


There is a lack of research that jointly discusses coastal dynamics and VLM at a local scale to date. Thus, this work provides a baseline to be used as a blueprint to track coastal dynamics and future ground motions once longer records of radar data become available. In addition to contributing to the explanation the chronic erosion of the study area, the outcomes of this project are relevant for engineers of a proposed expansion to the current highway.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/10 .3390/geosciences11070300/s1; Figure S1: VLM rates for 2017–2021 as derived from Sentinel 1A/B data and coastline changes for 2010–2020. Data was aggregated in (a) 1.5-km and (b) 5.0-km sections.

**Author Contributions:** J.F.G. performed the InSAR analysis with the support of E.K. and M.S.; J.F.G. performed coastal changes analysis with the assistance of I.J.W.; M.S. provided codes and expertise to perform InSAR analysis. All authors analyzed the results and contributed to the paper writing, editing and revisions. All authors have read and agreed to the published version of the manuscript.

**Funding:** This project was supported by funding provided to EK through an NSERC Discovery Grant. M.S. was supported by the National Aeronautics and Space Administration (NASA) grant 80NSSC170567.

**Data Availability Statement:** Processed data are available upon request to the first author.

**Acknowledgments:** The authors thank three anonymous reviewers for their constructive comments and feedback that improved the final manuscript. We are grateful to the following individuals and institutions for their input and support: Edwin Niessen, Alice Gentleman, Evaristo Rada, Ismael Fernández, Pro-Ciénaga Foundation, and to the staff of the Isla de Salamanca Park Way.

**Conflicts of Interest:** The authors declare no conflict of interest.
