Climate Change and Dynamics of the ITCZ on the Hydro-Climatic Regime of the Northern Ecosystems of the Gulf of Guinea: A Case of the Grand-Lahou Lagoon System

Abstract

Atmospheric dynamics and climatology in West Africa are strongly dominated by the latitudinal migration of the ITCZ which imposes directly or indirectly determinism on coastal ecosystems. Thus, the Grand-Lahou lagoon system and its watershed are influenced by the ITCZ, whose seasonal study made it possible to understand its mode of action first on climatic factors, then hydroclimatic , and finally hydrological in the context of global changes. The study of these factors showed a differentiated impact of its migration on the hydrol ogical regime defining a new configuration of the lagoon system and beyond; the coastal ecosystems of the northern coast of the Gulf of Guinea irrigated by numerous fluvial inputs. Salinity , a hydrological parameter of critical ecosystem importance, combined with transparency and depth, ha s en abled the spatio- temporal description of hydrology. To do this, a series of monthly measurements ( in-situ ) for spatial coverage of 25 stations was tested. Long before that, the climatic and hydroclimatic parameters were obtained respectively at SODEXAM, the meteorological site earth.nullschool.net and ONADE. This study brought together the dynamics of the ITCZ and the hydrological system of the lagoon.