DETERMINING THE EFFECTS OF CO2 OCEAN DISPOSAL ON DEEP-SEA ORGANISMS

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Ocean acidification The Other CO2 Problem
Jim Barry, Monterey Bay Aquarium Research
Institute

• CO2 emissions are making the oceans more acidic
• More acidic ocean is stressful for many marine
  organisms
• Potential for large effects on ocean ecosystems
  and society

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What is Ocean Acidification?
Carbon Dioxide
Carbonic acid
CO2
carbonate
bicarbonate
protons
HCO3- H
H20
CO3-2 H
H2CO3
Abundance in Seawater
Acidity
Marine Shells CaCO3
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Fossil Fuel Carbon Dioxide in the Ocean

• Fossil fuel CO2 to gt1000 meters
• gt500 billion tons of CO2 emissions in the ocean
  
• Ocean CO2 disposal is now 3 million tons per
  hour

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Physiological Effects on Organisms

• Shell and skeleton formation
• Respiratory Stress
• Enzyme Function
• Metabolic Depression

5
What are the options for organisms faced with
ocean acidification?

• Acclimation
• Adaptation
• Extinction

Hmmm..?
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Effects on individuals can affect ecosystems
Normal
Cost of Living
Growth
Energy Budget
Reproduction
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Present Ocean Food Web Diverse, Complex,
Productive
Primary Producers
What are the expected effects of ocean
acidification on ocean ecosystems?
Zooplankton food web
Upper Trophic levels
Sinking Organic Debris
Microbial Remineralization
Seafloor community
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Future Ocean Food Web Loss of biodiversity, low
productivity, dominated by microbial recycling?
Primary Producers

• Reduced Biodiversity
• Simplified Food Web
• Ecological Tipping Point?

Upper Trophic levels
Zooplankton food web
Sinking Organic Debris
Microbial Remineralization
Seafloor community
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What about California?

• Ecosystems with lower biodiversity
• Lower productivity
• Lower stability
• Lower resilience

• Potential effects of acidification / warming on
  our fisheries
• Reduced biodiversity,
• Increased variation in fishery catch
• More frequent fishery collapses
• Reduced potential for recovery

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The bottom line

• What we know
• Ocean acidification is ongoing, massive,
  increasing
• Causes physiological stress for many species
• Can only be mitigated by reduced CO2
  emissions
• What we expect
• Food webs will be affected
• Ecosystem services (e.g. fisheries) will
  change
• What we dont know
• Capacity for acclimation and adaptation
• Effects on marine communities, ecosystems -
  tipping points?
• What will this mean for California coastal
  states?
• Productivity and Stability of Fisheries

Multiple Stressors Synergistic effects of
warming, acidification, reduced oxygen levels may
further impact ocean ecosystems
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Value the Oceans