[1] Cape Finisterre is the most northwest point in the Galician region and separates the meridional west and zonal north coasts of Galicia. The wind field there has high spatial and temporal variability throughout the year. No clear seasonal signal is evident; upwelling and nonupwelling patterns alternate in all seasons. Two outstanding features of the Galician region are persistent upwelling near Cape Finisterre even when not present farther south and alternation of strong upwelling on north and west coasts. Up to now, explanations have relied upon particular dynamics of oceanic flow past Finisterre. We find that major features of upwelling around Finisterre are related to strong spatial structure in the wind field. Analysis of QuikScat wind data for July 1999 to May 2001 shows strong repeatable patterns in the synoptic wind field. These wind patterns emerge as the combination of the two dominant modes in a complex empirical orthogonal function (CEOF) analysis representing over 85% of the variance. Summer wind patterns give rise to characteristic distributions of upwelling along the coast and favor development of filaments in particular locations. The wind measured at Finisterre itself, often used as a general indicator of upwelling conditions around the Galician coast, is not always representative of the overall wind field. The relevant wind fields allowed a qualitative explanation of temperature structure seen in sea surface temperature images, and of differences in both the upwelling and downwelling regimes between the two years.INDEX TERMS: 4227 Oceanography: General: Diurnal, seasonal, and annual cycles; 4279 Oceanography: General: Upwelling and convergences; 4516 Oceanography: Physical: Eastern boundary currents; 4504 Oceanography: Physical: Air/sea interactions (0312); KEYWORDS: SeaWinds, coastal upwelling, sea surface temperature, air-sea coupling, Iberia, wind patterns Citation: Torres, R., E. D. Barton, P. Miller, and E. Fanjul, Spatial patterns of wind and sea surface temperature in the Galician upwelling region,

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We have studied the relation between the hydrography, the composition and horizontal structure of the larval fish community, and the horizontal distribution patterns of larval fish abundances in an area characterised by strong mesoscale oceanographic activity, located between the Canary Islands and the African coast (the Canaries Coastal Transition Zone), during August 1999. Upwelling, upwelling filaments, cyclonic and anticyclonic eddies and island wakes are typical mesoscale features of the northwest African coast in summer. A single upwelling filament off Cabo Juby was joined in mid-August by a second that originated about 100 km to the north. The two filaments flowed together and merged 100 km offshore. The merged filament was partially entrained around a cyclonic eddy, trapped between the Canary Islands and the African coast, and interacted with cyclonic and anticyclonic eddies shed from Gran Canaria. Mesoscale oceanographic features strongly influenced the horizontal distributions of fish larvae. Eddies acted as a mechanism of concentration, while upwelling filaments were

In August 1998, a recurrent filament located near 42°N off Galicia was sampled as part of the OMEX-II project. Lagrangian and other observations were made on the shelf where the filament arose and offshore in the filament itself under upwelling favourable but fluctuating winds. The shelf drift experiment monitored a change from southward to weak northward net flow as the winds decreased to zero. Shipborne ADCP measurements showed that the shelf was supplying decreasing volumes of water to the filament as the wind speeds decreased. At the shelf edge the internal tide was larger than can be explained by local forcing and there were many unusually large high frequency internal waves with a quasi-sinusoidal form. Turbulence observations revealed enhanced dissipation rates and vertical eddy diffusion coefficients within the shelf thermocline (of order 1 cm 2 s Ϫ1), which appeared to be caused by the breaking of internal wave. A second Lagrangian experiment was executed in the filament some 120 km offshore, which again coincided with a period of wind relaxation. Cross-sections revealed a double cold core and that the offshore flow was limited to a thin surface layer. Substantial onshore flow occurred below 50 m in the centre of the filament, while the strongest and deepest offshore flow coincided with its northern boundary. Turbulent kinetic energy dissipation rate measurements showed very weak mixing below 15 m in the filament core, but enhanced mixing at its boundaries. Four mixed layer drifters released in the filament initially indicated convergence at its southern boundary, marked by strong temperature and salinity contrasts. After the wind became more favourable for upwelling, the drifters accelerated. One drifter traced the full extent of the filament, while the other three escaped from it and began to circulate cyclonically over 28 days in a 100 km diameter loop back towards their release point. Although strong mesoscale activity linked the shelf and ocean regimes, offshore transport in the filament was weak at the time of the experiment and vertical and horizontal re-circulations on a variety of time scales were important. There was sufficient vertical mixing in the thermocline to cause it to thicken and draw some heat into the lower layers during the summer months on the shelf. The amount of heat involved was too little to have a significant impact on the development of a filament over a typical lifetime of a week. 