Costal sea level variability and extreme events in Moñitos, Cordoba, Colombian Caribbean Sea

Abstract

Flooding episodes occur frequently in the Colombian Caribbean and cause damage to coastal settlements. However, there is little knowledge about these episodes and about how changes in associated variables affect coastal flooding. This paper presents the results obtained from analyzing the temporal variability of flood levels in Moñitos-Córdoba on the Colombian Caribbean coast, as well as the contribution their components make to different time scales. To achieve this, the total sea level (TSL) was estimated indirectly as the sum of the variables involved (sea level anomalies, astronomical tide, storm surge and wave runup). These variables were obtained by applying numerical and empirical modeling using satellite altimetry data, tidal modeled data and wind, waves and atmospheric pressure from reanalysis. Data Trends and contributions were analyzed using statistical methods, including variance analysis, exceedance distributions, linear regressions, Sen-Slope and the Mann Kendall test. The results indicate that the total sea level has a semi-annual cycle with its highest maximum levels in the months of December to March and its lowest maximum levels in the months of April and September. The total sea level variability in Moñitos is dominated by the runup component at monthly, intra-annual and inter-annual scales, while at longer-term timescales (2–7 years and greater) variability is dominated by the sea level anomaly. Runup is the greatest contributor to the total sea level, followed by the sea level anomaly in average conditions and the astronomical tide in extreme conditions. There was a trend of increasing total sea level, related to the trend in sea level anomaly, with a consequent increasing trend of frequency and magnitude of extreme sea levels.