Coastal Upwelling • Equatorward winds along a coastline lead to offshore Ekman transport • Mass conservation requires these waters replaced by cold, denser waters • Brings nutrients into surface waters creating blooms • Creates dynamic height gradients - currents
Coastal Upwelling. Equatorward winds along a coastline lead to offshore Ekman transport Mass conservation requires these waters replaced by cold, denser waters Brings nutrients into surface waters creating blooms Creates dynamic height gradients - currents. Coastal Upwelling. - PowerPoint PPT Presentation
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Coastal Upwelling
• Equatorward winds along a coastline lead to offshore Ekman transport
• Mass conservation requires these waters replaced by cold, denser waters
• Brings nutrients into surface waters creating blooms
• Creates dynamic height gradients - currents
Coastal Upwelling
Coastal Upwelling
Coastal Upwelling
Coastal Upwelling
Coastal Upwelling
Coastal Upwelling
April 2000 CalCoFI Cruise
April 2000 CalCoFI Cruise
April 2000 CalCoFI Cruise
At smaller scales...
• Strong west winds
Ocean Biogeochemistry in a Nutshell
• Light energy drives the net fixation of carbon
• Within the euphotic zone, nutrients & CO2 produce CO2 & fixed carbon
• Below the euphotic zone, the rxn’s reverse
PelagicEcosystems
NUTS
CO2
Fixed Carbon
O2
h
Coastal Upwelling
• California Current
• April 1978
• AVHRR - SST
• CZCS Chlorophyll
SSTChl
Respiration & Remineralizati
on
remineralizers
h
CO2 O2
PlantsNUTS
Biological processes consume plants & O2 to make CO2 & nutrients
Euphotic Zone
Euphotic Zone – PP happens
Aphotic Zone - Respiration & Remineralization
Depth of Euphotic Zone is f(water clarity)
100% Light
1% Light
Euphotic Zone
• Defined as the depth where the light = 1% of the surface value
• A function of plant biomass or chlorophyll concentration
Increasing CO2: •Increases acidity (lowers pH)•Lowers CaCO3(s) saturation state “”Multiple forms of CaCO3: aragonite, calcite, Mg-calcite with different solubility
•humans, fish, whales-Possible negative effects on larvae
Biological Impacts
warm-water corals
cold-water corals
lobsters, crabs some plankton
pteropodsplanktonic snails
scallops, clams, oysters
Published by AAAS
R. A. Feely et al., Science 320, 1490 -1492 (2008)
Fig. 1. Distribution of the depths of the undersaturated water (aragonite saturation < 1.0; pH < 7.75) on the continental shelf of western North America from Queen
Charlotte Sound, Canada, to San Gregorio Baja California Sur, Mexico
Published by AAAS R. A. Feely et al., Science 320, 1490 -1492 (2008)
Fig. 2. Vertical sections of (A) temperature, (B) aragonite saturation, (C) pH, (D) DIC, and (E) pCO2 on transect line 5 off Pt George
Review• Wind stress along coasts leads to divergence of surface Ekman transport
• This drives to coastal upwelling and forms a coastal jet
• This drives the productivity of eastern boundary currents
• Important for acidification of the coastal ocean