1 surface circulation pathways generally, warm currents move poleward and cool currents move...
Post on 20-Dec-2015
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1
Surface Circulation Pathways
Generally, warm currents move poleward and cool currents move equatorward.
2
Effect of Ocean Heat Transport
Pattern of currents flow impacts sea surface temperatures and, as a result, air temperatures over land.
3
Equatorial Pacific: Sea Surface Temperature (SST)
4
El Nino Effects on Winter Air Temperatures in US
Temperature anomaly is plotted (Tobsv’d – Tmean)
5
Effect of El Nino on Anchovy Catch
Declines in fish catch correlate with El Nino events (red spikes).
6
Atmospheric CO2 Budget 1990s 1015 gm C yr-1
• Fossil Fuel Combustion 6.3±0.4• Deforestation 1.7±1• Total Human CO2 Source 8.0±1.1 • Atmospheric CO2 Accumulation 3.2±0.1
• Ocean CO2 Uptake 2.0±0.4
• Terrestrial CO2 Uptake (by difference) 2.8±1.1
Total CO2 Sink 4.8±1.5
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Anthropogenic CO2 Distribution in the Ocean
CO2 from fossil fuel combustion that has been absorbed by the ocean is found mostly in the upper 1000m.
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Photosynthesis Rates in the Ocean(satellite based estimates)
Where are the highest (red/yellow) and lowest (blue) photosynthesis rates found in the ocean?
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Sea Surface Temperature (SST)
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Depth vs Pressure
Density vs Temperature Density vs Pressure
11
CTD Measurements (pressure, temperature and conductivity)
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Equation of State for Seawater
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Density has non-linear dependence on T and S
Range in T, S and σ in the ocean
14
Dependence of temperature of maximum density and freezing point of seawater on salinity
Implies that cooling seawater with S<25 reaches the temperature of max density before the freezing point.
15
Cross Section of Potential Temp in Atlantic Ocean
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Depth Profiles of Temperature
7ºS
0 10 20ºC
63ºS
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Sea Surface Temperature (SST)
Most of surface ocean is warm. Only few regions at high latitudes where surface ocean temperatures approach temperatures in the Deep Sea.
(ºC)
18
Surface Solar Radiation (Watts/m2)
The equatorial region with highest solar radiation rates corresponds to the warmest SSTs.
19
Potential Temp Variations: 50m vs 2000m in Pacific
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Sea Surface Salinity
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Evaporation and Precipitation Effects on Surface Salinity
22
Salinity Cross Section in Atlantic Ocean
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Salinity Variations at the surface and 3000m in Pacific
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Sea Surface Density and SST: Pacific Ocean
The pattern of surface density closely follows the pattern of SST (but not surface salinity).
Potential Density
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Spatial variations of density- surface vs 3000m
Potential Density 50m Potential Density 3000m
Water is denser and more uniform in Deep Sea than surface ocean. Only near Antarctica in Pacific Ocean does surface potential density approach that of deep sea.
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Cross Section of Density (σθ) Pacific Ocean
Latitude
Dep
th (
m)
27
Depth Profiles of Density (σt)