Date post: | 26-Mar-2015 |
Category: |
Documents |
Upload: | david-joyce |
View: | 216 times |
Download: | 3 times |
Chemical Oceanography - 04
Introduction to the Physics and Biology of the Ocean
The School of Marine Sciences and Marine Environment
Ruppin Academic Center
Gitai Yahel ([email protected]), Tel.(09)866 3497 #110, Skype gitaiyahel, Web http://moodle.ruppin.ac.il
Monday, April 10, 2023 Chemical Oceanography, [email protected] (2)
The vertical structure of the ocean
Aphotic Deepsea ~3.8 km
Thermocline
Epipelagic zone
Station 230, East Atlantic, 1 Nov 1974, MedAtlas
Thermocline, nutricline, below 50-500 m
illuminated, warm, productive nutrient depleted, saline, 10-200 m
Permanent thermocline
The ocean interior (90% of the ocean volume)DeepColdDarkStableLow biological activity
Monday, April 10, 2023 Chemical Oceanography, [email protected] (6)
Water cycle, major reservoirs and fluxes
Environment Water Volume (km3)
Percentage of Total (% )
Surface Water Freshwater Lakes 125,000 0.01 Saline Lakes and Inland 104,000 0.009 Seas Rivers and Streams 1,200 0.0001 Total 230,000 0.019 Subsurface Water Soil Moisture 67,000 0.005 Ground Water (shallow, <750m) 4,000,000 0.3 Ground Water (deep, 750-4000m) 5,000,000 0.38 Total 9,067,000 0.685 Ice Caps and Glaciers 29,000,000 2.05 Atmosphere 13,000 0.001 Biosphere 600 0.00004 Oceans 1.37 x 109 97.25 Total 1.408 x 109
Monday, April 10, 2023 Chemical Oceanography, [email protected] (7)
Surface Sea Temperature distribution
• The sun is the major source of energy to the ocean
• Heat redistribution derive the global circulation
http://earth.usc.edu/~stott/Catalina/Oceans.html
An animation of average Sea Surface Temperature
Monday, April 10, 2023 Chemical Oceanography, [email protected] (8)
NASA: http://svs.gsfc.nasa.gov/vis/a000000/a003600/a003652/
Monday, April 10, 2023 Chemical Oceanography, [email protected] (9)
Latitudinal precipitation and salinity distribution
Surface seawater salinities largely reflect the local balance between evaporation andprecipitation.
Monday, April 10, 2023 Chemical Oceanography, [email protected] (10)
Global salinity distribution
• Ocean Salinity is fairly constant
Average Sea Surface Salinity
Monday, April 10, 2023 Chemical Oceanography, [email protected] (11)NASA: http://svs.gsfc.nasa.gov/vis/a000000/a003600/a003652/
Monday, April 10, 2023 Chemical Oceanography, [email protected] (12)
Regional thermocline structure
Sarmiento and Gruber 2005 Chapter2a
Tropics
Monday, April 10, 2023 Chemical Oceanography, [email protected] (14)
General circulation – surface currents
• The great gyres are the most prominent feature of the surface circulation
http://earth.usc.edu/~stott/Catalina/Oceans.html
Monday, April 10, 2023 Chemical Oceanography, [email protected] (15)
General circulation – surface currents
Upwelling zonesThe deep water that surfaces in upwelling is cold; by looking at Sea Surface Temperature maps we can identify cool upwelled water versus hotter surface water.
Equatorial Upwelling
Water Flow
Upwelling
Coastal Upwelling
Monday, April 10, 2023 Chemical Oceanography, [email protected] (19)
Schematic of thermohaline circulation.
http://earth.usc.edu/~stott/Catalina/Oceans.html
Sinking
The Thermohaline Circulation – The Great Ocean Conveyor Belt
Monday, April 10, 2023 Chemical Oceanography, [email protected] (20)
Monday, April 10, 2023 Chemical Oceanography, [email protected] (21)
North Atlantic circulation
• North Atlantic Deep Water (NADW) • Sources: Greenland Sea (80%) and Labrador Sea (20%)
Characteristics: Temperature of 2.5º C and salinity of 35.03
• North Atlantic deep water forms as warm, saline waters from the Gulf Stream moves northward, cooled and become more dense.
http://earth.usc.edu/~geol150/variability/deepocean.html
Monday, April 10, 2023 Chemical Oceanography, [email protected] (22)
The great global conveyor – simplified scheme
Monday, April 10, 2023 Chemical Oceanography, [email protected] (23)
The great global conveyor
from Aguado and Burt, Understanding Weather & Climate
Monday, April 10, 2023 Chemical Oceanography, [email protected] (24)
Implication for chemical oceanography
• Distinct Horizontal distribution pattern of chemicals in the ocean – the ocean is NOT fully mixed!o Mixing time 103 yearso Uneven distribution
of chemicals due to: Salinity Removal (e.g. burial) Addition (e.g., rivers) Transformation
(e.g., photosynthesis)
Monday, April 10, 2023 Chemical Oceanography, [email protected] (25)
Biological oceanography - the major players:
Primary producersGrazers
Decomposers+
Monday, April 10, 2023 Chemical Oceanography, [email protected] (26)
Energy and mass transfer – we use a simplified scheme
Monday, April 10, 2023 Chemical Oceanography, [email protected] (28)
Passage of energy between trophic levels
Monday, April 10, 2023 Chemical Oceanography, [email protected] (29)
Bio-geo-chemical cycling - mass cycled, energy is wasted…(as heat)
Mass balance and energy transfer
Monday, April 10, 2023 Chemical Oceanography, [email protected] (31)