Long Term Sea Level Change in the Gulf of Guinea from Multi- Mission Altimetry Data

Abstract

The sea level variations from 2000 to 2015 within the Gulf of Guinea and the Atlantic Ocean with satellite altimetry information acquired from TOPEX, ERS-2, ENVISAT, CRYOSAT-2, JASON-1, JASON-2 and SARAL missions have been examined. These sea level information was recaptured and processed using the radar altimeter database system (RADS). During processing with the RADS, the 2016 upgraded geophysical and environmental corrections were put in. For the altimetry data comparison, three tidal stations were chosen in order to ascertain the correlation that exists between the ocean tide models selected for the study. Similarity in the trends of sea level fluctuations betokens impressive acquiescent between altimetry data independently obtained with GOT4.10 and FES2004 ocean tide models (OTMs). From the 16 years’ altimetry data, results from both OTMs show positive sea level trend within the region. The sea level time series information from altimeter revealed that since 2000, the mean sea level in the Gulf of Guinea has been elevating—depending on the geography—at a rate of 2.4 mm/year and 3.6 mm/year with the GOT4.10 and FES2004 OTMs respectively. Also, both ocean tide models vary in the estimated sea level trends by 1.2 mm/year and have a root-mean-square difference of 1.3 cm. This kind of information is important for better understanding of the marine ecosystem, studying environmental talking points cognate to flooding probes and universal warming, overdue for an area that until now is yet to be adequately explored by the altimeter science community.