Play Video
1
World Ocean Circulation - California Current
World Ocean Circulation - California Current
::2008/11/18::
Play Video
2
Climate the California Current and CalCOFI - Perspectives on Ocean Science
Climate the California Current and CalCOFI - Perspectives on Ocean Science
::2010/03/11::
Play Video
3
Animation of the temporal evolution of ocean acidification in the California Current System
Animation of the temporal evolution of ocean acidification in the California Current System
::2012/06/15::
Play Video
4
California current prime interest rate and hard money
California current prime interest rate and hard money
::2010/09/24::
Play Video
5
Dr. Julia Stewart, Humboldt squid in the California Current System
Dr. Julia Stewart, Humboldt squid in the California Current System
::2014/05/05::
Play Video
6
Livermore California current real estate market conditions report by Steve Eveleth 925.487.2246
Livermore California current real estate market conditions report by Steve Eveleth 925.487.2246
::2014/07/09::
Play Video
7
Vanessa Van Zerr: Leatherbacks of the California Current
Vanessa Van Zerr: Leatherbacks of the California Current
::2013/08/09::
Play Video
8
California Current Vodcast
California Current Vodcast
::2014/03/18::
Play Video
9
Mark Ohman - Climate Variability and the California Current
Mark Ohman - Climate Variability and the California Current
::2012/04/30::
Play Video
10
Climate Variability and the California Current - Panel Discussion
Climate Variability and the California Current - Panel Discussion
::2012/04/30::
Play Video
11
Tony Koslow - Climate Variability and the California Current
Tony Koslow - Climate Variability and the California Current
::2012/04/30::
Play Video
12
David Checkley - Climate Variability and the California Current
David Checkley - Climate Variability and the California Current
::2012/04/30::
Play Video
13
Phytoplankton Biodiversity (Species Richness) in the California Current System
Phytoplankton Biodiversity (Species Richness) in the California Current System
::2011/12/17::
Play Video
14
Elliott Hazen - Climate Variability and the California Current
Elliott Hazen - Climate Variability and the California Current
::2012/04/30::
Play Video
15
Current Conditions - Northstar California
Current Conditions - Northstar California
::2014/01/21::
Play Video
16
History of Water in California, Current State of Water in San Fernando Valley
History of Water in California, Current State of Water in San Fernando Valley
::2010/09/14::
Play Video
17
First Breeder Salmon Shark Sport fishing California Current So Cal Bight Tagged and Released
First Breeder Salmon Shark Sport fishing California Current So Cal Bight Tagged and Released
::2012/06/07::
Play Video
18
Karin Forney - Climate Variability and the California Current
Karin Forney - Climate Variability and the California Current
::2012/04/30::
Play Video
19
History of Water in California,Current State of Water in San Feranando Valley by Fred Barker
History of Water in California,Current State of Water in San Feranando Valley by Fred Barker
::2010/09/01::
Play Video
20
How and Why California Employee Bargaining Units Decertify Their Current Representative
How and Why California Employee Bargaining Units Decertify Their Current Representative
::2013/07/01::
Play Video
21
California Current Aquarium Kelp Beds Oregon Coast Aquarium Newport OR
California Current Aquarium Kelp Beds Oregon Coast Aquarium Newport OR
::2010/09/05::
Play Video
22
Check out this Monster So California Rip Current
Check out this Monster So California Rip Current
::2010/05/03::
Play Video
23
Current water supply situation for California - Part 1
Current water supply situation for California - Part 1
::2014/04/11::
Play Video
24
Bar Brothers Requirements -- California Calisthenics 2.36s Current Record Fastest Time!
Bar Brothers Requirements -- California Calisthenics 2.36s Current Record Fastest Time!
::2013/06/13::
Play Video
25
California Workers Compensation Current Medical Treatment Senate Bill 863
California Workers Compensation Current Medical Treatment Senate Bill 863
::2014/04/02::
Play Video
26
KPIX Los Angeles California insurers have until 2014 to extend current health insurance plans
KPIX Los Angeles California insurers have until 2014 to extend current health insurance plans
::2013/11/15::
Play Video
27
Current Coasters on The Best of Southern California
Current Coasters on The Best of Southern California
::2013/12/04::
Play Video
28
1900 Lake Drive, Cardiff, California Current Upstairs
1900 Lake Drive, Cardiff, California Current Upstairs
::2010/10/20::
Play Video
29
Training California
Training California's First Responders to Deal with Current Issues
::2014/03/26::
Play Video
30
Danville CA Real Estate Get Current Market Analysis
Danville CA Real Estate Get Current Market Analysis
::2014/05/09::
Play Video
31
Gregory Hodge - Current Black Men & Boys Investments in California: A Landscape Scan (slides)
Gregory Hodge - Current Black Men & Boys Investments in California: A Landscape Scan (slides)
::2013/04/17::
Play Video
32
California Supreme - Alumni vs. Current Players - 2013 Hype.
California Supreme - Alumni vs. Current Players - 2013 Hype.
::2013/05/23::
Play Video
33
CT70K3 For Sale Trail 70 1974 with California title and current street registration
CT70K3 For Sale Trail 70 1974 with California title and current street registration
::2013/08/23::
Play Video
34
BNP California Protest for Bangladesh current political situation
BNP California Protest for Bangladesh current political situation
::2013/03/19::
Play Video
35
Part Four: The Current Economic Outlook for the Nation, California, and the Bay Area
Part Four: The Current Economic Outlook for the Nation, California, and the Bay Area
::2013/09/11::
Play Video
36
Danville California Real Estate Current Market Value Evaluation
Danville California Real Estate Current Market Value Evaluation
::2013/06/11::
Play Video
37
Storm Debarge | CURRENT QUEEN OF DOUGIE | California
Storm Debarge | CURRENT QUEEN OF DOUGIE | California's Top Female
::2011/11/13::
Play Video
38
BNP California Protest for Bangladesh current political situation-2
BNP California Protest for Bangladesh current political situation-2
::2013/03/19::
Play Video
39
Dr. John Field - Rockfish (Sebastes) recruitment and ecosystem indicators for the California Current
Dr. John Field - Rockfish (Sebastes) recruitment and ecosystem indicators for the California Current
::2014/04/18::
Play Video
40
american jihadist terrorist from california  Part of channel(s): Syria (current event)
american jihadist terrorist from california Part of channel(s): Syria (current event)
::2013/09/02::
Play Video
41
Oceanside California surf showing Rip Current 00025 リップカレント 瑞普电流
Oceanside California surf showing Rip Current 00025 リップカレント 瑞普电流
::2012/01/16::
Play Video
42
Current Luxury Apartments For Rent in San Diego, California
Current Luxury Apartments For Rent in San Diego, California
::2011/04/21::
Play Video
43
California current mortgage hard money rate and hard money
California current mortgage hard money rate and hard money
::2010/09/26::
Play Video
44
California what are the current interest rates and hard money
California what are the current interest rates and hard money
::2010/09/29::
Play Video
45
Breathe CA interviews Dr. Higashi M.D., Ph.D, on the current Tuberculosis Climate of California
Breathe CA interviews Dr. Higashi M.D., Ph.D, on the current Tuberculosis Climate of California
::2013/03/18::
Play Video
46
Donnie Athens sings for Tami Farrell  current Miss California
Donnie Athens sings for Tami Farrell current Miss California
::2009/10/16::
Play Video
47
California current interest rates home loans and hard money
California current interest rates home loans and hard money
::2010/09/29::
Play Video
48
California what are current mortgage rates and hard money
California what are current mortgage rates and hard money
::2010/09/27::
Play Video
49
Current Situation in California on Sharps Management - Janine Hamner, Waste Management
Current Situation in California on Sharps Management - Janine Hamner, Waste Management
::2012/02/01::
Play Video
50
California current mortgage rates new jersey and hard money
California current mortgage rates new jersey and hard money
::2010/09/26::
NEXT >>
RESULTS [51 .. 101]
From Wikipedia, the free encyclopedia
Jump to: navigation, search
The ocean currents.
Upwelling of colder sub-surface waters along the California coast is identified for the lack of clouds in this satellite image. The lack of clouds along the coast (and also along the Central Valley of California) is due to oceanic water's low temperature which make evaporation more difficult.

The California Current is a Pacific Ocean current that moves southward along the western coast of North America, beginning off southern British Columbia, and ending off southern Baja California. It is one of five major coastal currents affiliated with upwelling zones, the others being the Humboldt Current, the Canary Current, the Benguela Current, and the Somali Current.

The California Current is an Eastern boundary current and is also part of the North Pacific Gyre, a large swirling current that occupies the northern basin of the Pacific. The movement of northern waters southward makes the coastal waters cooler than the coastal areas of comparable latitude on the east coast of the United States. Additionally, extensive upwelling of colder sub-surface waters occurs, caused by the prevailing northeasterly winds acting through the Ekman Effect. The winds drive surface water to the right of the wind flow, that is offshore, which draws water up from below to replace it. The upwelling further cools the already cool California Current. This is the mechanism that produces California's characteristic coastal fog and the negative temperature anomaly we measure in California's coastal waters during summer (Mann and Lazier, 2006). This translates into cold coastal waters during the summer, stretching from Oregon to Baja California. Note, this does not include the coastal water surrounding San Diego. There is a warm water anomaly off San Diego (Mann and Lazier, 2006).

The cold water is highly productive due to the upwelling, which brings to the surface nutrient-rich sediments, supporting large populations of whales, seabirds and important fisheries. Winds of the appropriate direction and strength to induce upwelling are more prevalent in the presence of Eastern boundary currents, such as the California Current (Mann and Lazier, 2006). Phytoplankton production is dramatically increased in these areas because the nutrient-rich water lying below the pycnocline is relatively close to the surface and is thus easily upwelled (Mann and Lazier, 2006). Scientists at Scripps Institution of Oceanography said in 2011 that the average surface temperature of the water at Scripps Pier has increased by almost 3 degrees since 1950.[1]

A narrower, weaker counter current, the Davidson Current, occasionally moves somewhat warmer water northwards during the winter months. During El Niño events, the California Current is disrupted, leading to declines in phytoplankton, resulting in cascading effects up the food chain, such as declines in fisheries, seabird breeding failures and marine mammal mortality (Schwing et al., 2003). In 2005, a failure in the otherwise predictable upwelling events, unassociated with El Niño, caused a collapse in krill in the current, leading to similar effects (Schwing et al., 2003).

Bakun (1973) calculated a 20-year average of the monthly mean Ekman transport for different regions off the California coast. His 'Bakun upwelling index' ranges from 300 meters-cubed/second (in the offshore direction) to -212 meters-cubed/second (toward the coast, or onshore direction) (Mann and Lazier,2006). Bakun's index showed there is year-round upwelling off Southern California's coast, but it is strongest in the summer months. Bakun's work also shows that off the coast of Oregon and Washington, there is forceful downwelling in the winter months, and upwelling in the region is restricted to the months of April through September (Mann and Lazier, 2006).

Primary production[edit]

Primary production is a topic of interest among those who study the California Current. In their study, Hayward and Venrick (1982) found great variability in both biomass and the productivity of phytoplankton in the California Current. The differences observed by Hayward and Venrick in carbon-fixation rates (0.2-2.0 grams Carbon/(meter-squared x day)) show the heterogeneous nature of the California Current, with its combination of advected (see advection) and upwelled water. Several studies have investigated the carbon flow from primary production to the pelagic fish stocks which depend on the California Current. Lasker (1988) described powerful 'jets and squirts' off northern and central California. These 'jets and squirts' move large quantities of cold, nutrient rich water offshore. This water then gets carried by the southward bound California Current and adds significant primary production to the sardine population (Mann and Lazier, 2006).

Physical properties[edit]

The Southern California Bight is a sub-region of the California Current and has unique physical properties. Upwelling is fairly weak in the California Bight and Smith and Eppley (1982) stated that the 16-year average for primary production was 0.402 grams Carbon/(meter-squared x day),or approximately 150 grams carbon/(meter-squared x year). Further, Smith and Eppley (1982) found that the highest daily rates of temperature decrease were correlated with the maximum amount of upwelling (Mann and Lazier, 2006). Digiacomo and Holt (2001) used satellite images to study the mesoscale and sub-mesoscale eddies in the Southern California Bight. Their work showed that all eddies were less than 50 km in diameter and 70% of all eddies measured less than 10 km (Mann and Lazier, 2006). The eddies appeared to be caused mostly by topography (particularly islands), wind, and instabilities in the current. The location of these eddies was mainly between the California Current (flowing toward the equator) and the coastline (Mann and Lazier, 2006). The majority of these eddies were cyclonic and had the ability to induce the upwelling of nutrient-rich water. Small scale topographic features such as headlands have been shown to cause substantial effects on the population dynamics of benthic invertebrates, such a change in the settlement patterns of crabs and sea urchin (Mann and Lazier, 2006).

Fish production and growth[edit]

The California Current produces an abundance of sardines, anchovies, hake, jack mackerel, and mackerel (Mann and Lazier, 2006). An abundance of these fish species is a common feature of eastern boundary currents. Sardines in particular were heavily fished from 1916 - 1967. This led to the California state legislature to impose a suspension on sardine fishing in 1967 (Mann and Lazier, 2006). The largest stocks of both sardine and anchovy spawn in the Southern California Bight. Sardines in the California Current are divisible into four stocks and anchovies in this current have several subpopulations as well (Mann and Lazier, 2006). The California Bight is a region of relatively weak upwelling (and thus weak phytoplankton production) compared to the greater California Current. From these observations, we see that fish often choose to spawn in areas where Ekman transport will not carry their eggs too far offshore. Many fish species avoid spawning in areas of strong upwelling. Although upwelling and the subsequent high biological productivity produces optimal conditions for the growth of juvenile and adult sardines, the absence of strong upwelling in late winter and early spring (such as that found in the California Bight) is what creates optimum conditions for the survival of fish larvae (Mann and Lazier, 2006). Once anchovy and sardine larvae have spent a significant amount of time in waters free of strong upwelling and mixing (i.e. The California Bight), they migrate (as juveniles) toward areas of great upwelling (i.e. The California Current proper). There the juveniles can take advantage of the high biological productivity and maximize their growth rate.

See also[edit]

References[edit]

  1. ^ Lee, Mike (June 18, 2011). "Is global warming changing California Current?". U-T (San Diego Union Tribune). Retrieved June 20, 2011. 
  • Carina Stanton. Warmer oceans may be killing West Coast marine life. Seattle Times. 13 July 2005. Retrieved 22 March 2008.
  • Mann, K.H., Lazier, J.R.N. 2006. Dynamics of Marine Ecosystems: Biological-Physical Interactions in the Oceans. Third Edition. Blackwell Publishing. pp. 166–167, 194-204.
  • Schwing, M.R., Mendelssohn, R., Bograd, S.J. 2003. El Nino Impacts of the California Current Ecosystem. Report produced by NOAA Fisheries, Southwest Fisheries Science Center. 1-8.

External links[edit]

Wikipedia content is licensed under the GFDL License
Powered by YouTube
LEGAL
  • Mashpedia © 2014