Guinean EEZ - Environment

The marine environment is subject to a strong continental influence. Domain et al. (1999) note that the Guinean rivers are subject to alternating seasons (dry and wet) and are thus richer in nutrients than the equatorial rivers fed by continuous rains. These terrigenous intrusions occupy much of the continental shelf. They can be formed either by quartz sands with frequent presence of lateritic gravel, or just by mud/silt. These muds of terrestrial origin ensure biological fertilization of the Guinean coastal waters and contribute to the great fishery resources potential of this area. Apart from these terrestrial influences, the northern part of the Guinean continental shelf is under the influence of the Senegalese upwelling system. In Guinean the hydrological seasons, characterized by changes in temperature and salinity, correspond to two main climatic seasons. The hydrological cold season is the dry season (December to May). During this period, despite reduced inflow of fresh water, a layer of desalinated water still persists along the coast of Guinea, although significantly less important than in rainy season (Fontana, (Ed.) 1995). At this time the surface temperatures remain fairly homogeneous and are close to 27°C. The warm hydrological season is the rainy season (June to November), during which the continental freshwater contributions due to high rainfall are important. This season is characterised by relatively homogenous sea surface temperatures relatively homogeneous between 26°C and 29°C (Domain et al., 1999). Relative humidity ranges between 49.6 and 97.8% with 2 to 8.6 hours of sunshine daily, depending on the season (Baran, 1995). In the West African region, upwelling takes place primarily from January to May. In the warm season when the influence of cold upwelling is mimimal, river inflow replaces upwelling as the mechanism of coatsla ocean enrichment.