The California Current System in relation to the Northeast Pacific Ocean circulation

The California Current System is described in its regional setting using two modern datasets. Argo provides a broadscale view of the entire eastern North Pacific Ocean for the period 2004–2010, and the High Resolution XBT Network includes transects from Honolulu to San Francisco (1991–2010) and to Los Angeles (2008–2010). Together these datasets describe a California Current of 500–800 km width extending along the coast from 43°N to 23°N. The mean southward transport of the California Current is about 5 Sv off Central and Southern California, with about 2.5 Sv of northward flow on its inshore side. Interannual variations are 50% or more of the mean transports. The salinity minimum in the core of the California Current is supplied by the North Pacific Current and by freshwater from the northern continental shelf and modified by alongshore geostrophic and across-shore Ekman advection as well as eddy fluxes and air–sea exchange. The heat and freshwater content of the California Current vary in response to the fluctuating strength of the alongshore geostrophic flow. On its offshore side, the California Current is influenced by North Pacific Intermediate Waters at its deepest levels and by Eastern Subtropical Mode Waters on shallower density surfaces. In total, the sources of the California Current, its alongshore advection, and its strong interactions with the inshore upwelling region and the offshore gyre interior combine to make this a rich and diverse ecosystem. The present work reviews previous contributions to the regional oceanography, and uses the new datasets to paint a spatially and temporally more comprehensive description than was possible previously.

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Vertical Plankton Tow (VPT) data from 1997 - 2003 from multiple cruises from the Northeast Pacific, California Current System (NEP project)

Biological and Chemical Oceanography Data Management Office ◽

10.1575/1912/bco-dmo.2453.1 ◽

2010 ◽

Author(s):

William Peterson

Keyword(s):

Current System ◽

California Current ◽

California Current System ◽

Northeast Pacific

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SMAP and CalCOFI Observe Freshening during the 2014–2016 Northeast Pacific Warm Anomaly

Remote Sensing ◽

10.3390/rs10111716 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1716 ◽

Cited By ~ 2

Author(s):

Jorge Vazquez-Cuervo ◽

Jose Gomez-Valdes

Keyword(s):

Soil Moisture ◽

Current System ◽

Mixed Layer Depth ◽

California Current ◽

Layer Depth ◽

Surface Salinity ◽

California Coast ◽

California Current System ◽

Northeast Pacific ◽

Warm Anomaly

Data from NASA’s Soil Moisture Active Passive Mission (SMAP) and from the California Cooperative Oceanic Fisheries Investigations (CalCOFI) were used to examine the freshening that occurred during 2015–2016 in the Southern California Current System. Overall, the freshening was found to be related to the 2014–2016 Northeast Pacific Warm Anomaly. The primary goal was to determine the feasibility of using SMAP data to observe the surface salinity signal associated with the warming and its coastal impact. As a first step, direct comparisons were done with salinity from the CalCOFI data at one-meter depth. During 2015, SMAP was saltier than CalCOFI by 0.5 Practical Salinity Units (PSU), but biases were reduced to <0.1 PSU during 2016. South of 33°N, and nearer to the coast where upwelling dominates, SMAP was fresher in 2015 by almost 0.2 PSU. CalCOFI showed freshening of 0.1 PSU. North of 33°N, SMAP and CalCOFI saw significant freshening in 2016, SMAP by 0.4 PSU and CalCOFI by 0.2 PSU. Differences between SMAP and CalCOFI are consistent with the increased stratification in 2015 and changes in the mixed layer depth. SMAP observed freshening that reached the Baja California Coast.

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The GLOBEC Northeast Pacific California Current System Program

Oceanography ◽

10.5670/oceanog.2002.20 ◽

2002 ◽

Vol 15 (2) ◽

pp. 36-47 ◽

Cited By ~ 45

Author(s):

Harold Batchhelder ◽

John Barth ◽

Michael Kosro ◽

Ted Strub ◽

Richard Brodeur ◽

...

Keyword(s):

Current System ◽

California Current ◽

California Current System ◽

Northeast Pacific ◽

System Program

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Weak constraint four-dimensional variational data assimilation in a model of the California Current System

Advances in Statistical Climatology Meteorology and Oceanography ◽

10.5194/ascmo-2-171-2016 ◽

2016 ◽

Vol 2 (2) ◽

pp. 171-192 ◽

Cited By ~ 1

Author(s):

William J. Crawford ◽

Polly J. Smith ◽

Ralph F. Milliff ◽

Jerome Fiechter ◽

Christopher K. Wikle ◽

...

Keyword(s):

Data Assimilation ◽

Ocean Circulation ◽

Hierarchical Modeling ◽

Current System ◽

California Current ◽

Model Errors ◽

Strong Constraint ◽

California Current System ◽

Twin Model ◽

Error Covariance

Abstract. A new approach is explored for computing estimates of the error covariance associated with the intrinsic errors of a numerical forecast model in regions characterized by upwelling and downwelling. The approach used is based on a combination of strong constraint data assimilation, twin model experiments, linear inverse modeling, and Bayesian hierarchical modeling. The resulting model error covariance estimates Q are applied to a model of the California Current System using weak constraint four-dimensional variational (4D-Var) data assimilation to compute estimates of the ocean circulation. The results of this study show that the estimates of Q derived following our approach lead to demonstrable improvements in the model circulation estimates and isolate regions where model errors are likely to be important and that have been independently identified in the same model in previously published work.

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SMAP and CalCOFI Observe Freshening During the 2014-2016 Northeast Pacific Warm Anomaly

10.20944/preprints201807.0181.v1 ◽

2018 ◽

Author(s):

Jorge Vazquez ◽

Jose Gomez-Valdes

Keyword(s):

Soil Moisture ◽

Mixed Layer ◽

Current System ◽

Mixed Layer Depth ◽

California Current ◽

Layer Depth ◽

Surface Salinity ◽

California Current System ◽

Northeast Pacific ◽

Warm Anomaly

Data from NASA’s Soil Moisture Active Passive Mission (SMAP) and from the California Cooperative Oceanic Fisheries Investigations (CalCOFI) were used to examine the freshening that occurred during 2015-2016 in the Southern California Current System. Overall the freshening was found to be related to the 2014-2016 Northeast Pacific Warm Anomaly. The primary goal was to determine the feasibility of using SMAP data to observe the surface salinity signal associated with the warming. As a first step direct comparisons were done with salinity from the CalCOFI data at one-meter depth. During 2015 SMAP was saltier than CalCOFI by 0.5 PSU, but biases were reduced to < 0.1 PSU during 2016. South of 33°N, and within 100 km of the coast, SMAP was fresher in 2015 by almost 0.2 PSU. CalCOFI showed freshening of 0.1 PSU. North of 33°N SMAP and CalCOFI saw significant freshening in 2016, SMAP by 0.4 PSU and CalCOFI by 0.2 PSU. Differences between SMAP and CalCOFI are consistent with the increased stratification in 2015 and changes in the mixed layer depth.

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