. Commercial fisheries review. Fisheries; Fish trade. 29 with the position of the Gabon-Angola Front. The area of the Front was generally covered with broken cumulus clouds, but no pattern or discontinuity was discernible that could be related tothe known position of the Front. During the cruise periodj the Front was weakly developed and involved gradients that never actually constituted a frontal configu- ration. The strongest horizontal gradient of sea surface temperature for the 23° to 25° C. range (the range usually involved in the center of the frontal gradient) was 2° C. in 30 nau- tical
. Commercial fisheries review. Fisheries; Fish trade. 29 with the position of the Gabon-Angola Front. The area of the Front was generally covered with broken cumulus clouds, but no pattern or discontinuity was discernible that could be related tothe known position of the Front. During the cruise periodj the Front was weakly developed and involved gradients that never actually constituted a frontal configu- ration. The strongest horizontal gradient of sea surface temperature for the 23° to 25° C. range (the range usually involved in the center of the frontal gradient) was 2° C. in 30 nau- tical miles. Sharper gradients were found around small nearshore patches of cool (less than 21°C.)upwelled water, but these had an apparent effect on cloud formation in only a few photographs--perhaps because of the small size of the upwelling areas. CONCLUSIONS This study has revealed that it is not feasible to monitor the position of the Gab on- Angola Front from satellite data during the September-December period, assuming that the oceanic and atmospheric conditions en- countered on UNDAUNTED cruise 6802 were typical. Apparently the gradients involved in the Front during this period were too weak to produce an abrupt change in cloud cover. A distinct pattern in the cloud cover was observed consistently off South-West Africa and South Africa, which is apparently related to cool sea surface temperatures from up- welling or advection of the Benguela Current. The large clear zone associated with the cloud pattern should provide a useful environment for air-sea interaction and satellite monitor- ing feasibility studies for the following rea- sons: (1) The presence of the clear zone is predictable. (2) Its boundaries are sharply delimited and probably reflect sharp sea sur- face temperature gradients. (3) It changes shape, mainly along the northern limit of the zone in a period of less than 24 holirs. (4) Cumulus, stratus, and clear areas could be studied within a radius of about 5
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