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Each summer, large quantities of freshwater and associated dissolved and particulate material are released from the Greenland Ice Sheet (GrIS) into local fjords where they promote local phytoplankton growth. Whether the influx of freshwater and associated micronutrients in glacial meltwater is able to stimulate phytoplankton growth beyond the fjords is disputed, however. Here we show that the arrival of freshwater discharge from outlet glaciers from both southeast and southwest GrIS coincides with large‐scale blooms in the Labrador Sea that extend over 300 km from the coast during summer. This summer bloom develops about a week after the arrival of glacial meltwater in early July and persists until the input of glacial meltwater slows in August or September, accounting for ~40% of annual net primary production for the area. In view of the absence of a significant change in the depth of the mixed layer associated with the arrival of glacial meltwater to the Labrador Sea, we suggest that the increase in phytoplankton biomass and productivity in summer is likely driven by a greater nutrient supply (most likely iron). Our results highlight that the ecological impact of meltwater from the GrIS likely extends far beyond the boundaries of the local fjords, encompassing much of the eastern Labrador Sea. Such impacts may increase if melting of the GrIS accelerates as predicted.

Data from the SeaWinds scatterometer on the QuikSCAT satellite are used to estimate upwelling around Cabo Frio, Brazil, due to Ekman transport and Ekman pumping. The region close to shore (up to 200 km from the coast) is characterized by negative wind stress curl (upwelling favorable) year‐round, with maximum values during summer, and minimum values during fall. Integrated values from São Sebastião Island to Vitória reveal that during summer, Ekman pumping and Ekman transport are of the same magnitude in the region. Estimates of Ekman transport are relatively uniform along the coast during summer. Ekman pumping, on the other hand, is strongly enhanced between São Sebastião Island and Vitória, the region where the coldest water on satellite images is frequently found. This suggests that wind stress curl‐driven upwelling is a major contributor to the coldest surface water being found near Cabo Frio.

[1] Repeated mesoscale surveys of waters over the shelf and slope off Oregon were conducted during spring and summer of 2001 to study the spatial structure of the velocity and hydrographic fields. The ocean response to wind forcing is compared between a region of relatively simple topography with alongshore uniformity and a region of complex topography including a shallow submarine bank (Heceta Bank). In the simple topography region the upper water column is influenced by upwelling and fresh water from the Columbia River during spring, with the low-salinity water located farther offshore during summer. Variability in the fields is mostly confined within 30 km from the coast. Over Heceta Bank the region of higher variability is broader, spanning most of the shelf. The coastal upwelling jet is located inshore of the pinnacle of the bank during spring, moving offshore during summer. The region inshore of the bank is characterized by low velocities and flow recirculation. Near-surface fields show that the circulation evolves considerably between seasons. In both regions the area influenced by upwelled water is much broader during summer. Dense waters found over midshelf off Newport are upwelled to the north and advected south. Dense waters inshore of Heceta Bank are substantially influenced by water from the north during spring, but their source is mostly from the south during summer. South of the bank, the separation of the jet significantly increases the cross-isobath transport, constituting an efficient mechanism for transport of material from the shelf into deeper waters.Citation: Castelao, R. M., and J. A. Barth (2005), Coastal ocean response to summer upwelling favorable winds in a region of alongshore bottom topography variations off Oregon,

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