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The Carbon Cycle and Ocean Acidification Notes

The Carbon Cycle and Ocean Acidification Notes

Introduction to the Carbon Cycle

  • Carbon is a fundamental element present in all living organisms and is a key component of many geological and biological processes.
  • The carbon cycle describes how carbon moves through the Earth's systems, including the atmosphere, land, oceans, and living organisms.

Ocean Acidification

  • Definition: Ocean acidification refers to the decreasing pH levels in the Earth's oceans caused by the uptake of carbon dioxide (CO2) from the atmosphere.
  • Known as climate change's "evil twin," ocean acidification has significant implications for marine life and ecosystems.

Key Agenda Items

  1. View Bozeman Science's video on ocean acidification (20 min)
  2. Conduct a bicarbonate in water lab activity (40-60 min)
    • Ensure understanding of the following:
      • pH of tap vs. carbonated water
      • Relationship between CO2, carbonic acid, bicarbonate, and carbonate
      • Changes in ocean pH from 1751 to present
      • Bjerrum plot and its implications
      • Interaction between global warming, ocean acidification, and the carbon cycle
  3. Review information from NSF Ice Core Facility on tracking CO2 through ice cores (if time permits)

Discussion Questions During Video

  • pH Comparison:
    • pH of tap water vs. pH of carbonated water
  • Sketch/Diagram Relationships:
    • Relationship between CO2, carbonic acid (H2CO3), bicarbonate ion (HCO3-), and carbonate ion (CO3^2-)
  • Definition of pH:
    • pH is a measure of the acidity or basicity of a solution based on hydrogen ion concentration.
  • Historical Ocean pH Changes:
    • Document the drop in ocean pH levels and its impact over time (1751-present).
  • Bjerrum Plot:
    • Represents the distribution of CO2, HCO3-, and CO3^2- as a function of pH.
  • Interconnections:
    • Explain how global warming promotes ocean acidification and how both are linked to the carbon cycle.

Bicarbonate in Water Lab

  • Chemical Reactions:

    • The relationship between water and carbon dioxide can be shown by the equation:

    CO2 + H2O ⇌ H2CO3 ⇌ H+ + HCO3-

    • Where:
      • CO2 = Carbon dioxide
      • H2O = Water
      • H2CO3 = Carbonic acid
      • H+ = Hydrogen ion
      • HCO3- = Bicarbonate ion

  • This lab activity explores the dynamics of bicarbonate in water and its relevance in ocean environments and the carbon cycle.