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Fields of coastal wind stress and wind stress curl in the 10–100 km next to the land control the processes of upwelling and downwelling of nutrients and water properties that are vital to highly productive coastal marine ecosystems. Here we ask the question: Do the present surface wind stress products from a satellite-borne scatterometer (QuikSCAT) and an atmospheric reanalysis model (ERA-5) systematically overestimate the magnitude of wind speed and stress in the 10–50 km next to the coast? We compare QuikSCAT wind speed retrievals to the relatively unused wind speed retrievals from satellite altimeters, which are able to approach closer to the coast than scatterometers without land reflections, due to their smaller radar footprints. Altimeter data on tracks approaching and crossing the coast indicate that the increases in coastal QuikSCAT wind speed values and ERA-5 coastal wind stress values are unrealistic. For analyses of wind speed and stress requiring high accuracy, especially those involving wind stress curl, we suggest considering individual Level 2B scatterometer wind retrievals as suspect at distances of 10 km and less from the coast, along with use of the Poor Coastal Processing flag. We found that similar increases in wind stress values next to the coast in gridded ERA-5 fields are not due to errors in the model physics or wind speeds. They are created during the interpolation of wind stress from the original model grid to a regular rectangular grid. We recommend that researchers who are analyzing wind stress and wind stress curl should calculate wind stress themselves from the gridded ERA-5 vector wind speed fields, rather than using the interpolated model wind stress or curl fields.

The goal of the Pacific Ocean Boundary Ecosystem and Climate Study (POBEX) was to diagnose the large-scale climate controls on regional transport dynamics and lower trophic marine ecosystem variability in Pacific Ocean boundary systems. An international team of collaborators shared observational and eddy-resolving modeling data sets collected in the Northeast Pacific, including the Gulf of Alaska (GOA) and the California Current System (CCS), the Humboldt or Peru-Chile Current System (PCCS), and the Kuroshio-Oyashio Extension (KOE) region. POBEX investigators found that a dominant fraction of decadal variability in basin- and regional-scale salinity, nutrients, chlorophyll, and zooplankton taxa is explained by a newly discovered pattern of ocean-climate variability dubbed the North Pacific Gyre Oscillation (NPGO) and the Pacific Decadal Oscillation (PDO). NPGO dynamics are driven by atmospheric variability in the North Pacific and capture the decadal expression of Central Pacific El Niños in the extratropics, much as the PDO captures the low-frequency expression of eastern Pacific El Niños. By combining hindcasts of eddy-resolving ocean models over the period 1950–2008 with model passive tracers and long-term observations (e.g., CalCOFI, Line-P, Newport Hydrographic Line, Odate Collection), POBEX showed that the PDO and the NPGO combine to control low-frequency upwelling and alongshore transport dynamics in the North Pacific sector, while the eastern Pacific El Niño dominates in the South Pacific. Although different climate modes have different regional expressions, changes in vertical transport (e.g., upwelling) were found to explain the dominant nutrient and phytoplankton variability in the CCS, GOA, and PCCS, while changes in alongshore transport forced much of the observed long-term change in zooplankton species composition in the KOE as well as in the northern and southern CCS. In contrast, cross-shelf transport dynamics were linked to mesoscale eddy activity, driven by regional-scale dynamics that are largely decoupled from variations associated with the large-scale climate modes. Preliminary findings suggest that mesoscale eddies play a key role in offshore transport of zooplankton and impact the life cycles of higher trophic levels (e.g., fish) in the CCS, PCCS, and GOA. Looking forward, POBEX results may guide the development of new modeling and observational strategies to establish mechanistic links among climate forcing, mesoscale circulation, and marine population dynamics.

Physical processes, biotic processes and human activities all act to shape marine ecosystems. Future management of these valuable ecosystems requires an integrative approach that takes into account complicated organismal interactions, oceanographic processes that span large scales of time and space, and how anthropogenic effects interact with the natural environment. The temperate west coasts of North and South America represent a unique opportunity for comparison, as many of the same oceanographic processes, particularly upwelling, occur off both coasts. Additionally, a number of marine ecosystems in both areas have surprising parallels. Here we present an overview of the oceanographic processes that dominate the coastlines, and give examples of ecosystems and the effects that oceanography, human activities and their interaction have on the communitiesLos procesos físicos y biológicos y las actividades humanas determinan los ecosistemas marinos. El manejo futuro de estos valiosos ecosistemas requiere de una aproximación integrativa que considere las complejas interacciones entre individuos, los procesos oceanográficos que se desarrollan a gran escala espacial y temporal, y la interacción de los efectos antropogénicos con el medio ambiente. Las costas templadas del oeste de Norteamérica y Sudamérica representan una oportunidad única para efectuar comparaciones ya que muchos procesos oceanográficos, particularmente la surgencia costera, ocurren en ambas costas. Adicionalmente, numerosos ecosistemas marinos en ambas áreas presentan sorprendentes paralelos. La presente revisión ofrece una visión general de los procesos oceanográficos dominantes en ambas costas y ofrece ejemplos de ecosistemas y los efectos que la oceanografía, las actividades humanas y las interacciones entre individuos tienen sobre las comunidades marinas

Sea surface height (SSH) fields, constructed from multiple altimeters, have revealed the annual generation of anticyclonic eddies around the Alaska Gyre. These eddies appear to develop annually along the eastern margin of the Gyre from instabilities in the poleward Alaska Current, after it reaches its seasonal maximum in transport in winter. After forming, the eddies propagate westward just offshore of the continental slope, where they draw shelf water containing nutrients and phytoplankton into the deep offshore waters, as seen by the SeaWiFS satellite ocean color sensor. In this manner, they enrich a region of the ocean that is dominated by downwelling-favorable wind forcing. Off Chile, the Cape Horn Current is the analog of the Alaska Current, flowing poleward and driven by cyclonic winds, associated with winter storms. In this presentation we will use satellite fields of SSH and Chlorophyll-a pigment concentrations to examine the relatively unstudied Cape Horn Current and compare its seasonal behavior to the Alaska Current. We will specifically look for anticyclonic eddies, similar to those in the Alaska Gyre

We develop, utilize, and validate techniques to produce a global data set of accurate coastal ocean surface vector winds. The dataset extends as near to the coast as 5 km and includes 10 years of SeaWinds on QuikSCAT ocean scatterometer data obtained from 1999 to 2009. We demonstrate improved retrievals over other large land-locked bodies of water as well, such as the Caspian Sea and the Great lakes. To determine the coastal winds we quantify the extent of land contamination in each scatterometer backscatter measurement and to the extent possible remove that contamination. After the measurements are thus corrected we retrieve winds with the corrected measurements using a previously published algorithm which has been extensively used for JPL scatterometer wind products. The coastal processing vastly increases the number of wind vector cells near coasts. We have ten times the number of wind vectors within 10 km of coast as without coastal processing, and over twice as many at 20 km from coast. These new wind vectors are high-quality, and have zero effect on non-coastal wind vectors. The effect of residual land contamination is quantified by comparing to buoys at varying distance from the coast and comparing coastal wind vector cells to oceanward neighbors. We show that the non-coastal QuikSCAT processing has very few good wind vectors nearer to the coast than about 22.5 km. In comparison to buoys, and oceanward neighbors, we find a small increase in speed errors of these new coastal wind vectors versus the performance of non-coastal QuikSCAT at 22.5 km, indicating the high-quality of these new coastal wind vectors. A quality control scheme is employed that flags regions where the coastal wind retrieval is poor due to the assumptions inherent in the technique being locally invalid. The coastal winds retrieved in this manner have been publicly distributed to the oceanography community and utilized in other published works.