1.1 Introduction, chemical composition of SW

Learning objectives:

  • Describe the properties of saltwater that are important to how the ocean circulates
  • Understand differences between units and why it matters
  • Broadly distinguish physical / circulation differences between different ocean basins
  • Identify different elemental behavior and explain the rationale for classification

Hydrogen bonding

Salinity

Measurement

Impact on Circulation

Stratification and Mixing

  • Mixing happens along isopycnals, not isobars - multiple orders of magnitude faster mixing along isopycnals than across (diapycnal mixing)

  • Video from day 2:

Circulation and Biology

  • As waters age (circulate through the ocean, out of contact with the atmosphere) they accumulate the signal of respiration
  • [ photosynthesis / respiration equation]

Section view \(\neq\) Actual Circulation

  • [gif of SAMW pathway from observations]

Units

  • Volume vs. mass in the denominator?

The impact of pressure on temperature and density (in-situ vs. potential)

[-In-situ vs. potential temperature figures]

Element Classification

Composition of the Atmosphere

Gas Solubility

1.2 Ocean circulation, Geochemical Mass Balances

Types of circulation - overturning vs. wind-driven

Wind-driven circulation

Upwelling, gyres, ekman pumping, impact on biology

Seasonal mixing

  • seasonal mixed layer changes depth due to seasonal variability in wind speed, surface heating
  • below the seasonal thermocline you have a permanent thermocline

Geochemical mass balances

  • Two types:
    • Balance bewteen reactants and products
    • Geochemical cycles, balance of inputs/outputs with reservoirs

<embed src=”https://sethbushinsky.github.io/OCN623_Chemical_Oceanography/assets/pdfs/Geochemical_Mass_Balance.pdf”

  • Video from day 3:

Terminology:

  • Concentration vs. flux vs. transport vs. reservoir
Term Descr. Units
Concentration Quantity per unit mass or volume mol \(O_2\) kg\(^{-1}\) or mol \(O_2\) m\(^{-3}\)
Flux Movement of some quantity across a boundary per unit time mol \(O_2\) m\(^{-2}\) d\(^{-1}\)
Reservoir Amount contained in a volume or mass mol \(O_2\)
Transport Total movement of a quantity mol \(O_2\) d\(^{-1}\) or m d\(^{-1}\)

1.3 Gas solubility and Exchange

Gas Solubility

  • Video from day 4:

Gas Exchange

1.4 Hydrothermal systems

  • Video from day 5: