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The cyanobacteria Prochlorococcus and Synechococcus are important marine primary producers. We explored their distributions and covariance along a physico-chemical gradient from coastal to open ocean waters in the Northeastern Pacific Ocean. An inter-annual pattern was delineated in the dynamic transition zone where upwelled and eastern boundary current waters mix, and two new Synechococcus clades, Eastern Pacific Clade (EPC) 1 and EPC2, were identified. By applying state-of-the-art phylogenetic analysis tools to bar-coded 16S amplicon datasets, we observed higher abundance of Prochlorococcus high-light I (HLI) and low-light I (LLI) in years when more oligotrophic water intruded farther inshore, while under stronger upwelling Synechococcus I and IV dominated. However, contributions of some cyanobacterial clades were proportionally relatively constant, e.g. Synechococcus EPC2. In addition to supporting observations that Prochlorococcus LLI thrive at higher irradiances than other LL taxa, the results suggest LLI tolerate lower temperatures than previously reported. The phylogenetic precision of our 16S rRNA gene analytical approach and depth of bar-coded sequencing also facilitated detection of clades at low abundance in unexpected places. These include Prochlorococcus at the coast and Cyanobium-related sequences offshore, although it remains unclear whether these came from resident or potentially advected cells. Our study enhances understanding of cyanobacterial distributions in an ecologically important eastern boundary system. © 2014 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

In 2013, the California current was dominated by strong coastal upwelling and high productivity. Indices of total cumulative upwelling for particular coastal locations reached some of the highest values on record. Chlorophyll a levels were high throughout spring and summer. Catches of upwelling-related fish species were also high. After a moderate drop in upwelling during fall 2013, the California current system underwent a major change in phase. Three major basin-scale indicators, the PDO, the NPGO, and the ENSO-MEI, all changed phase at some point during the winter of 2013/14. The PDO changed to positive values, indicative of warmer waters in the North Pacific; the NPGO to negative values, indicative of lower productivity along the coast; and the MEI to positive values, indicative of an oncoming El Niño. Whereas the majority of the California Current system appears to have transitioned to an El Niño state by August 2014, based on decreases in upwelling and chlorophyll a concentration, and increases in SST, there still remained pockets of moderate upwelling, cold water, and high chlorophyll a biomass at various central coast locations, unlike patterns seen during the more major El Niños (e.g., the 97-98 event). Catches of rockfish, market squid, euphausiids, and juvenile sanddab remained high along the central coast, whereas catches of sardine and anchovy were low throughout the CCS. 2014 appears to be heading towards a moderate El Niño state, with some remaining patchy regions of upwellingdriven productivity along the coast. Superimposed on this pattern, three major regions have experienced possibly non-El Niño-related warming since winter: the Bering Sea, the Gulf of Alaska, and offshore of southern California. It is unclear how this warming may interact with the predicted El Niño, but the result will likely be reduced growth or reproduction for many key fisheries species.

The article of record as published may be located at http://dx.doi.org/10.10 29/2002GL015729, 2003 A 2-dimensional variational method is used to blend the satellite scatterometer measured (QuikSCAT) and regional mesoscale atmospheric model simulated (COAMPS) surface vector winds for coastal central California. The approach is distinct from existing methods in that it considers errors from both measurements and models. When compared with independent in situ observations, the blended wind product shows consistently higher correlation and smaller RMS errors than QuikSCAT or COAMPS winds. The proposed algorithm can be implemented over any part of the world ocean. It should be a valuable tool for describing small-scale atmospheric processes in coastal zones and for forcing highresolution coastal ocean models. The research described in this paper was carried out, in part, at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA). Support from National Oceanographic Partnership Program (NOPP) is acknowledged. The participation of JCK was also funded through the Naval Research Laboratory (NRL) 6.1 CoBALT ARI and the Dynamics of Coupled Models project under program element 61153N sponsored by the Office of Naval Research.

The fisherman of northern Peru coined the name El Niño in the late nineteenth century for a warm southward current that appeared every year around Christmas (the Christ child – El Niño). Years of unusually high rainfall in northern Peru were associated with an intensification of the annual current. It was not until the 1960s that Bjerknes (1966) linked warming of the coastal ocean off Peru (and the equatorial Pacific) with larger scale climatic phenomena. It was then that a relatively small and inoffensive coastal current (Chavez, 1986) was associated with dramatic global weather disturbances. Over the last 30 years the influence of El Niño on oceanic and atmospheric conditions throughout the globe has been well documented (Rasmusson and Wallace, 1983; Philander, 1990). More recently, in the 1980s, Peruvian scientists coined the name La Niña for anomalously cool temperatures along Peru. This phenomenon also has significant climatic impacts.

Ecosystems of the eastern boundary regions of the ocean basins, like those off California, Northwest Africa and Peru, are known for enhanced primary production and resulting large clupeid fisheries. In these eastern boundary regions, the basin-scale circulation brings the thermocline, pycnocline and nutricline close to the surface and often in contact with the mixed layer. Processes such as coastal upwelling then act to bring these cool and nutrient-rich waters to the surface. Photosynthesis is stimulated by the enhanced nutrient supply to sunlit waters, and food for supporting the ecosystem is generated. The source and fate of this primary production is variable, reflecting the dynamic physical character of eastern boundary systems. The physical and biological variability are most notable on mesoscale or subseasonal (upwelling events, jets and eddies), seasonal (spring transition, upwelling, winter) and interannual (El Nifio) scales. Decadal and interdecadal oscillations are evident in the longer time series (Hayward, 1996; Ingraham Jr. et al., 1998) and the analysis of White et al. (1997) suggests that the Northeast Pacific, and the California Coast in particular, are regions of higher than average decadal and interdecadal variability. And of course, the shadow of global warming looms on the horizon, if not already underway. Considering these factors, and the planning and implementation of major multi-disciplinary programs along the West Coast of North America (GLOBEC, CoOP), we have assembled a series of papers dealing with the oceanography of California waters into a volume of Deep Sea Research II.

Schwing et al.: The California Current, 1996-1997, CalCOFI Rep., Vol. 38, 1997 A large number of data sets from within the California Current region, and the large-scale fields that affect this region, are available for timely assessment of recent environmental conditions in this system. In addition to the long-running quarterly CalCOFI cruises, which featured the initial research cruise of RV Roger Revelle, several surveys off Baja California and central California have provided information on coastal areas adjacent to the present CalCOFI coverage. Conditions throughout the north Pacific and in the California Current are summarized and interpreted for the 1996-97 period.

Warm conditions in the North Pacific in 2014-15 were a result of the continuation of the North Pacific marine heat wave, a large area of exceptionally high SST anomalies that originated in the Gulf of Alaska in late 2013. The North Pacific heat wave interacted with an El Niño developing in the equatorial Pacific in 2015. Weekly periods of exceptionally high temperature anomalies (>2˚C) occurred until the start of the El Niño (winter of 2015), when SSTs were still high but not as high as those due to the marine heat wave. During the 2015-16 El Niño, the depth of the 26.0 kg m-3 isopycnal (d26.0) was considerably shallower than during the 1982- 83 and 1997-98 events. The area affected by the marine heat wave and the 2015-16 El Niño in the mixed layer was comparable to the 1997-98 El Niño, but lasted longer. Water column stratification in the upper 100 m during 2015-16 was as strong as the most extreme values during the 1997-98 El Niño. This stratification was primarily driven by the warming of the upper 100 m. Despite notable perturbations, the effects of the 2015- 16 El Niño on hydrographic properties in the CalCOFI domain were not as strong as those observed during the 1997-98 El Niño. Warm ocean conditions, stratification, nutrient suppression, and silicic acid stress likely favored initiation of a toxic Pseudo-nitzschia bloom in fall 2014. Very low zooplankton displacement volumes were associated with anomalously warm and saline surface waters off Baja California. In contrast, during the 1997-98 El Niño, zooplankton volume was near average. Off California, pelagic red crab (Pleuroncodes planipes) adults were abundant in the water column and frequently washed up on beaches of southern California from January 2015 into 2016, and central California by September 2015. Glider measurements of integrated transport up to June 2015 did not detect anomalous northward advection. As expected, HF radar indicated northward surface currents along the central California coast in fall and winter 2015-16. Northward advection appeared to be much stronger during the 1997-98 El Niño. Throughout 2015-16, the zooplankton community on the Oregon shelf was dominated by lipid-poor tropical and sub-tropical copepods and gelatinous zooplankton, indicating poor feeding conditions for small fishes that are prey for juvenile salmon. The presence of rarely encountered species increased copepod species richness during 2015-16 to levels higher than the 1998 El Niño. We infer that the unusual copepod vagrants of 2015-16 originated from an offshore and southwesterly source; an important difference from the southerly origin of vagrants during the 1997-98 El Niño. The very warm conditions caused sardine spawning to shift from central California to Oregon. Mesopelagic fish assemblage off southern California exhibited higher abundances of species with southern affinities, and lower abundances of species with northern affinities. Forage fish (Pacific herring, northern anchovy, and Pacific sardine) were much less abundant in 2015-16 compared to previous years. In contrast, catches of salmon were close to average off northern California. Catches of young-ofthe- year rockfishes were high off central California, but low off both northern and southern California. Seabirds at Southeast Farallon Island in 2015 exhibited reduced breeding populations, reduced breeding success, lower chick growth rates, and lower fledging weights. Common murres were negatively affected in central and northern California, but seabird responses were species-specific. It is clear from the results presented here that the warm anomaly effects on the ecosystem were complicated, regionally specific, and that we do not fully understand them yet.

This report reviews the state of the California Current System (CCS) between winter 2012 and spring 2013, and includes observations from Washington State to Baja California. During 2012, large-scale climate modes indicated the CCS remained in a cool, productive phase present since 2007. The upwelling season was delayed north of 42°N, but regions to the south, especially 33° to 36°N, experienced average to above average upwelling that persisted throughout the summer. Contrary to the indication of high production suggested by the climate indices, chlorophyll observed from surveys and remote sensing was below average along much of the coast. As well, some members of the forage assemblages along the coast experienced low abundances in 2012 surveys. Specifically, the concentrations of all lifestages observed directly or from egg densities of Pacific sardine, Sardinops sagax, and northern anchovy, Engraulis mordax, were less than previous years’ survey estimates. However, 2013 surveys and observations indicate an increase in abundance of northern anchovy. During winter 2011/2012, the increased presence of northern copepod species off northern California was consistent with stronger southward transport. Krill and small-fraction zooplankton abundances, where examined, were generally above average. North of 42°N, salps returned to typical abundances in 2012 after greater observed concentrations in 2010 and 2011. In contrast, salp abundance off central and southern California increased after a period of southward transport during winter 2011/2012. Reproductive success of piscivorous Brandt’s cormorant, Phalacrocorax penicillatus, was reduced while planktivorous Cassin’s auklet, Ptychoramphus aleuticus was elevated. Differences between the productivity of these two seabirds may be related to the available forage assemblage observed in the surveys. California sea lion pups from San Miguel Island were undernourished resulting in a pup mortality event perhaps in response to changes in forage availability. Limited biological data were available for spring 2013, but strong winter upwelling coastwide indicated an early spring transition, with the strong upwelling persisting into early summer.