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| Kifani, S; Gohin, Francis. |
| A space-time approach is adopted in an attempt to understand changes in the availability of the central sardine stock along the northwestern Moroccan coast. The warming observed in 1987 and 1989, due to the decline in wind activity, seems to have some repercussions on sardine distribution. The decrease in upwelling activity seems to have favoured concentration in the vicinity of Safi, and thus rendered the sardines more vulnerable to the purse-seiners of this port. We seek to explain the failure of the link established by Belveze and Erzini (1983) between sardine availability and upwelling activity in thc northern area. Two hypotheses, taking into account the local hydrology or the tendency of pelagic species to aggregate in time and space, have been put... |
| Tipo: Text |
Palavras-chave: UPWELLING; MOROCCO; SARDINE; SEA SURFACE TEMPERATURE. |
| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00100/21151/18770.pdf |
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| Currie, Ri. |
| Observations made during the International Indian Ocean Expedition provide the basis for a description of the summer circulation in the upper 500 m of the western Arabian Sea, off the coast of Oman. Under the influence of the south-west monsoon a pronounced geostrophic current develops along at least 1 000 km off the South-East Arabian coast between Ras Fartak and Ras al Hadd in May and the strong south-westerly wind brings about offshore transport of the surface layers between 55-degrees and 60-degrees-E. Water is upwelled onto the continental shelf from depths of about 150 m and this creates a strong negative sea-surface temperature anomaly along the coast, reaching a maximum development in July-August. With the decline of the monsoon upwelling ceases in... |
| Tipo: Text |
Palavras-chave: CIRCULATION; UPWELLING; ARABIAN SEA; COAST OF OMAN; IIOE. |
| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00100/21175/18792.pdf |
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| Binet, D; Servain, J. |
| Sea surface temperature along the northern coast of the Gulf of Guinea drops abruptly twice a year, with a moderate decrease in boreal winter and a greater one in summer. Several mechanisms have been proposed to explain these coolings: Ekman upwelling due to local wind, remote wind forcing in the western Atlantic, geostrophic adjustment to the Guinea current variations or eddies created by headlands in the current. The resulting seasonally-induced plankton production has led to the development of pelagic fisheries, with dramatic increases in Sardinella aurita catches in Cote d'Ivoire and Ghana during the last decade and new spatial and seasonal distributions. A study to account for these changes was undertaken on the basis of wind and temperature data... |
| Tipo: Text |
Palavras-chave: CLIMATIC CHANGE; PELAGIC FISHERIES; UPWELLING; WEST AFRICA. |
| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00099/21052/18678.pdf |
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| Colin, C. |
| The wind, temperature and current data collected during the joined French-USA FOCAL/SEQUAL programme carried in the equatorial Atlantic band in 1983 and 1984, allowed for the first time a simultaneous study of both the equatorial and coastal (5-degrees-N) upwellings along 4-degrees-W. At the equator, the decreases of both the surface temperature and the depth of the thermocline in boreal summer are correlated with the zonal component of the local windstress in the period band 1-2 months. This corresponds to the time required by the thermocline to lift up at 0-4-degrees-W in the presence of an easterly wind. The local wind cannot however explain the entire vertical variability of the thermal structure at 0-4-degrees-W. The correlation function shows in... |
| Tipo: Text |
Palavras-chave: GULF OF GUINEA; UPWELLING; EQUATOR; ADVECTION; DIFFUSION. |
| Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/00101/21252/18865.pdf |
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