Seasonal sea level cycle in the Caribbean Sea

Abstract

[1] The seasonal sea level cycle has been investigated in the Caribbean Sea using altimetry and tide gauge time series from 27 stations and is characterized by large spatial variability. The coastal annual harmonic has amplitudes that range from 2 cm to 9 cm, peaking between August and October and semi-annual harmonic with maximum amplitude of 6 cm, with most stations peaking in April and October. The coastal seasonal sea level cycle contributes significantly at most areas to sea level variability and can explain the sea level variance up to 78%. The barometric effect on the coastal sea level seasonal cycles is insignificant in the annual component but dominant at 9 stations in the semi-annual cycle. The seasonal sea level cycle from 18 years of altimetry confirm the results obtained from the tide-gauges and allow us to identify some dominant sea level forcing parameters in the annual and semi-annual frequencies such as the Panama-Colombia gyre driven by the wind stress curl and the Caribbean Low Level Jet modulating the sea level in the northern coast of South America and linked to the local upwelling. The seasonal sea level cycle in the Caribbean Sea is unsteady in time, with large variations in amplitude and phase lag at most of the stations, where the 5-year amplitude in the coastal annual cycle can change over 6 cm in a 24 year period. The seasonal sea level cycle peaks about October when the probability of coastal impacts increases, especially in the northern coast of South America where the range is larger.

Sea level extremes in the Caribbean Sea

“…The largest occurrence of annual maxima nontidal extremes in the Caribbean Sea is from August to November (black bars in Figure 6). This is partially due to the seasonal cycle contribution, which peaks in the second part of the year especially during September and October [Torres and Tsimplis, 2012]. The distribution of the annual maxima extremes through the year after the seasonal cycle has been removed is more uniform.…”

“…Smaller significant negative trends are also found in the 95th and 99th nontidal percentiles at the same station. Trends in the nontidal extremes are likely to be due to secular changes in the storm surges, as trends in the seasonal cycle were not found [Torres and Tsimplis, 2012]. If the annual mean sea level is not removed in Cristobal for this 71 year period (Figure 4), the upper nontidal residual percentiles show significant positive trends; thus, the mean sea level positive trend prevails over the negative trend in the nontidal residual.…”

“…The effect of the seasonal cycle on the nontidal annual maxima extremes distribution is assessed by removing the mean annual and semiannual cycles found by Torres and Tsimplis [2012] from the hourly nontidal residual. This was performed at all stations except Le Robert, where the effect of the seasonal cycle was not assessed due to the shortness of the observational record.…”

“…The hurricane season is from June to November, with a peak from mid August to late October (National Hurricane Center-http://www.nhc.noaa.gov/climo/). Note that the hurricane season coincides with the peak of the seasonal contribution (September-October), while the months with large probability of stationary cold fronts coincide with the seasonal trough (January-March) [Torres and Tsimplis, 2012].…”

Efectos de la descarga estacional del Canal del Dique en el mecanismo de intercambio de aguas de una bahía semicerrada y micromareal: Bahía de Cartagena, Colombia

“…De otro lado, en la costa norte suramericana el ciclo estacional del nivel del mar tiene un pico en los meses de octubre, incrementando la probabilidad de impactos en la costa [11].…”