TITLE:
Overview of Tide Characteristics in Cameroon Coastal Areas Using Recent Observations
AUTHORS:
R. Onguene, E. Pemha, F. Lyard, Y. Du-Penhoat, G. Nkoue, T. Duhaut, E. Njeugna, P. Marsaleix, R. Mbiake, S. Jombe, D. Allain
KEYWORDS:
Tide, Cameroon Coast, Harmonic Analysis, Prediction
JOURNAL NAME:
Open Journal of Marine Science,
Vol.5 No.1,
January
13,
2015
ABSTRACT: Time series of sea level
heights have been collected at different stations along the Cameroon coast. The dataset covers a period ranging
from 2007 to 2012. Tide data measured by float type recorders have been digitalized and
quality-controlled with tools developed at Laboratoire d’Etudes Géophysique et
Océanographie Spatiale (LEGOS). Short gaps in the data have been interpolated
while large gaps were not. Tide constituents were retrieved through harmonic
analysis using 123 waves having a period ranging from long ones to
eighth-diurnal ones. The reconstructed signal is used to assess the quality of
both the data and the analysis and the erroneous records were examined and
corrected. The effect of the hourly averaging of the raw data on the quality of
the analysis is also investigated. The tide constituents having the largest
amplitudes are, as expected, the semi-diurnal, diurnal, fourth-diurnal and long
term constituents. The major components of semi-diurnal waves are the M2 and S2
tides. The M2 tide height ranges between 0.5 and 0.85 m. The maximum height is
found at Cameroon estuary and the minimum at the Kribi station located in the
South coast. The S2 constituent varies similarly as the M2 constituent. Its
amplitude ranges between 0.18 and 0.52 m. The lowest S2 amplitude occurs also
at Kribi station. In the Dibamba estuary the spectrum shows a larger number of
significant semi-diurnal and fourth-diurnal waves than other zones. Concerning
diurnal waves, the dominant one is the K1 tide and its amplitude is homogeneous
along the coast. The influence of the long-term components is the strongest in
the Cameroon estuary due to important fluctuations of the rivers run-off.