28 research outputs found
Map of the study zone and model domains.
<p>(A) first domain (FD); (B) large domain (LD); (C) location of estuaries used in the model showing the shelf area adjacent to each estuary where larvae were emitted and recruited; (D) Ria de Aveiro; and (E) Canal de Mira. (C) also shows details of the 50, 100, 250 and 500 m isobaths of the smoothed bathymetry used in the model. Arrow in (E) indicates location where the passive nets were deployed.</p
Effect of PLD on larval distance.
<p>Average dispersal distance of successfully recruiting larvae supplied to the Ria de Aveiro from northern estuaries as a function of planktonic larval duration predicted by the Invasion models.</p
Predicted trajectory density and observed larval abundance in coastal waters.
<p>Onshore/offshore distribution of trajectory density predicted by the Base experiments with (light blue) and without (dark blue) diel vertical migration for (A) 2006 and (B) 2007; and (C) abundance of larvae (all stages combined) recorded by the Heincke 09 cruise in April of 1991, normalized by area of sea surface. Trajectory density was calculated between the parallels 40°00′ and 41°30′N, which was the area sampled by the cruise. The broken line in each panel represents the average position of the shelf break at ca. 43 km from shore.</p
Observed and predicted time series of supply in 2006.
<p>(A) Daily numbers of observed megalopal supply (continuous line), along-shore wind stress (dashed line) and spring tides (tidal range larger than long-term average range, grey bars) in the Ria de Aveiro in 2006; and predicted time series of supply by the Invasion experiments with (B) normal, (C) fast and (D) slow growth rates with (dashed line) and without (continuous line) mortality, for the same year.</p
Observed and predicted time series of supply in 2007.
<p>(A) Daily numbers of observed megalopal supply (continuous line), along-shore wind stress (dashed line) and spring tides (tidal range larger than long-term average range, grey bars) in the Ria de Aveiro in 2007; and predicted time series of supply by the Invasion experiments with (B) normal, (C) fast and (D) slow growth rates with (dashed line) and without (continuous line) mortality, for the same year.</p
Estimates of the average realized dispersal of successfully recruiting larvae.
<p>Average dispersal distance (km) of successfully recruiting larvae (realized dispersal) for the different Invasion model experiments and years.</p
Cross-correlations and time lags between observations and predictions.
<p>Cross-correlations (<i>r</i>) and time lags (d, in brackets) between observations and predicted time series, for the different Invasion model experiments and years. Reported values refer to maximum cross-correlations in each case, which were always significant at the 5% level.</p
Conceptual schemes of circulation under (a) upwelling regime and (b) relaxation regime.
<p>The prevalent currents are depicted on the transect by the dashed countours in red (poleward flowing) and blue (equatorward flowing) and identified with the acronyms: Iberian Poleward Current (IPC), Upper Slope Equatorward Current (USEC), Upwelling Jet (UJ) and Coastal Poleward Current (CPC). On the transect, dark lines represent the preceived field of isothermals and reddish areas mark location of central waters with subtropical origin. At the surface, the perceived paths of currents are marked as arrows, and the upwelling center as the blue (a) and purple (b) shading, representing a stronger and weaker temperature anomaly, respectively.</p
Zonal transects numbered 1 and 9 of temperature (left column) and salinity (right column) off Cape Silleiro (42,10°N).
<p>Day and time of each CTD cast and the underway surface temperature and salinity from the thermosalinograph are shown at the top. Dark contour lines represent along-shore (left column) and cross-shore (right column) currents in m/s measured with lADCP or vmADCP, when available. White contour lines are the 26 kg/m<sup>3</sup> and 27 kg/m<sup>3</sup> isopycnals on the left plots and the 35.6 and 35.8 isohalines on the right.</p
Transient response of the Northwestern Iberian upwelling regime
<div><p>The hydrography and dynamics of NW Iberian margin were explored for July 2009, based on a set of in situ and remote sensing observations. Zonal sections of standard CTD casts, towed CTD (SeaSoar), Acoustic Doppler Current Profilers (ADCP) and Lagrangian surveys were made to characterize cycles of upwelling and relaxation in this region. Two periods of northerly winds, bounded by relaxation periods, were responsible for the formation of an upwelling front extending to the shelf edge. An equatorward flow was quickly set up on the shelf responding to the northerly wind pulses. South of Cape Silleiro, the development and subsequent relaxation of an upwelling event was intensively surveyed in the shelf, following a Lagrangian drifter transported by the upwelling jet. This region is part of an upwelling center extending from Cape Silleiro to Porto, where the surface temperature was colder than the neighboring regions, under upwelling favorable winds. As these winds relaxed, persistent poleward flow developed, originating south of the upwelling center and consisting in an inner-shelf tongue of warm waters. During an event of strong southerly wind, the poleward flow was observed to extend to the whole continental shelf. Although the cruise was executed during summertime, the presence of river-plumes was observed over the shelf. The interaction of the plumes with the circulation on the shelf was also described in terms of coastal convergence and offshore advection. The sampling of the offshore and slope regions showed the presence of the Iberian poleward current offshore and a persistent equatorward flow over the upper slope.</p></div