1. Ocean acidification M. Debora Iglesias-Rodriguez
Based on “An International Observational Network for Ocean Acidification”
by Feely et al, and other stories.
Hoegh-Guldberg et al. 2007

2. Time series of atmospheric CO2
Mauna Loa data: Dr. Pieter Tans, NOAA/ESRL (
HOTS/Aloha data: Dr. David Karl, University of Hawaii ( (modified after Feely, 2008).

3. Emerging and established ocean acidification programmes
The Federal Ocean Acidification Research and Monitoring (FOARAM) Act passed Congress (March 25, 2009)
NERC Ocean Acidification Programme
The Natural Environment Research Council and the Department for Environment, Food & Rural Affairs are developing a collaborative 5 year research programme of ~ £12m.

4. Central Issues Interactions between biota and water chemistry
Effects of ocean acidification on marine calcifiers
Quantify synergistic effects from other environmental variables, (e.g., temp)
What determines the capacity of organisms to adapt to ocean acidification?
Threshold levels (tipping points) at the organism and community level
Societal impacts (socio-economics of ocean acidification) - e.g., effect of declining pteropod populations on fish stock?
from Pörtner et al., 2004)

5. Some facts about ocean acidification
Since industrialization, pCO2 has increased from 280 to 387 ppm: decrease of ~0.1 units at a rate of ~ yr-1 (Caldeira & Wickett, 2003, 2005; Bates & Peters, 2007; Santana-Casiano et al., 2007).
pCO2 will reach >800 ppm circa 2100: additional decrease (0.3 pH units).
Present pCO2 is higher than experienced on Earth for the last 800,000 yrs
Continuing pCO2 rise will lead to significant temperature increases

6. Chemistry of ocean acidification
Increasing carbon dioxide (CO2) in seawater causes the formation of carbonic acid (H2CO3), which causes acidification. Effects:
[CO2] increase   photosynthesis
[HCO3-] increase: CO2 + H2O  H2CO3  H+ + HCO3-  2H+ + CO32-   calcification
[CO32–] decrease, and the ocean’s saturation state with respect to CaCO3 (calcite/aragonite) ():
 = f{[CO32–], [Ca+2]}  calcification ?

7. Chemistry of ocean acidification
Increasing carbon dioxide (CO2) in seawater causes the formation of carbonic acid (H2CO3), which causes acidification. Effects:
[CO2] increase   photosynthesis
[HCO3-] increase: CO2 + H2O  H2CO3  H+ + HCO3-  2H+ + CO32-   calcification
[CO32–] decrease, and the ocean’s saturation state with respect to CaCO3 (calcite/aragonite) ():
 = f{[CO32–], [Ca+2]}  calcification ?

8. ? Carbonic anhydrase Carbonic anhydrase Ca+2 ATPase Carbonic anhydrase
CO2
H2O
HCO3-

9. pH in intracellular compartments: 7. 2 - 7
pH in intracellular compartments: for cytosol, nucleoplasm, mitochondria, plastid stroma (Raven, pers com).
Carbonic anhydrase ?
~30’’
Carbonic anhydrase
CO32-
~2’’
CO32-
Ca+2 ATPase
Carbonic anhydrase
CO2
H2O
HCO3-

10. Phytoplankton functional type adaptation
Diatoms
Coccolithophores
Riebesell et al., Nature, 2000.
Langer et al., G32006.
Iglesias-Rodriguez et al., Science, 2008.

11. carbonate
bicarbonate
Adaptation???

12. Acclimation - how?
Adaptation - who wins?

13. Main questions
What is the long term adaptation to fast rate of change?
What is the susceptibility of organisms to changes in pH?
Can we build an ocean observation network that can accounts for biological complexity?
Can we improve our knowledge on cell physiology and adaptation with the current experimental approaches?
What is the effect of functional group dominance on biogeochemistry?
So far:
- Lab experiments
- Mesocosm experiments
- Field observations and monitoring - what latitudes?

14. Calcium carbonate saturation
Royal Society report on ocean acidification, 2005
St. Petersburg report on ocean acidification, 2007
Orr et al., 2005.

15. CO2 sampling system attached to one of NOAA's Integrated Coral Observing Systems (ICON) in the Bahamas
Joanie Kleypas, NCAR Lead Scientist; 
Chris Langdon, and colleagues at the Rosentiel School of Oceanography, University of Miami; 
James Hendee and Rik Wanninkhof, NOAA.

17. Regional organismal and ecosystem response to increased CO2 from shipboard surveys
Just completed 1st August 2009:
On-deck mesocosm ecosystem perturbations with gradients of pH and organic carbon
Responses of phytoplankton and zooplankton to increased CO2 and changing stoichiometry of food supply
Assessment of regional ”natural” stoichiometry of production and export
Richard Bellerby and Frede Thingstad

18. Community requirements
A coordinated regional and global network of observations, process studies, manipulative experiments and modelling.
Identify natural variability of carbonate chemistry.
Identify whether or not there are geochemical thresholds for ocean acidification that will lead to irreversible effects on species and ecosystems over the next few decades.
Investigate long-term adaptation.
Strategy:
Repeat surveys of chemical and biological properties
Time-series measurements at stations and on floats & gliders

19. Measurement Requirements for the Ocean Acidification Observational Network
DIC, pCO2, TA and pH
Particulate inorganic carbon (PIC), particulate organic carbon (POC) and bio-optical measurements
Oxygen
Other biological measurements (specific DNA sequences for marine bar-coding, physiological rates, genomics and proteomics)
Nutrients, salinity
Suspended [PIC] (MODIS/ Terra). (a) January–March. (b) April–June. (c) July–September. (d) October–December (after Balch et al, 2007).

20. Time Series Measurements on Moorings, Gliders and Floats
Carbon and pH sensors on time-series moorings can resolve short space-time scale variability of the upper ocean - OceanSITES time-series.
Some of these locations: intensified process studies: e.g. open ocean mesocosm experiments, coastal mesoscale CO2 release experiments.
Coastal sites: effect of upwelling, riverine input - biogeochemical models that address specifically ocean acidification.
These monitoring systems can provide verification for the models: open ocean large-scale biogeochemical models and coastal data will verify nested high resolution coastal models.
Carbon system sensors could also be deployed on floats and gliders to resolve shorter space-time scale variability of the upper ocean.
Potential ocean acidification monitoring sites (coral reefs)

21. Underway Volunteer Observing Ship Network
Ships equipped with carbon system sensors and ancillary technologies (e.g. autonomous water samplers, nutrient analyzers) for ocean acidification should be added to the present carbon network.
These should be supported with technology to study OA (DNA sensors, PIC and POC production rates, supported by satellite measurements).

22. New ‘-omics’ approaches
Dupont et al., 2008.

23. If cells are in the water, what are they doing?
Meta-approaches
Diversity of marine microbial communities: ‘metagenomics’ (Venter et al. 2004, Delong et al. 2006, Sogin et al. 2006)
Functional properties of marine communities: ‘proteomics’ (Jones, Edwards, Skipp, O’Connor, Iglesias-Rodriguez, 2009)
If cells are in the water, what are they doing?
Genome Genes Static
Proteome Phenes Evolving
proteomics

24. Sampling: Sampling: Sampling:
385 or 1500 ppm CO2
2.4L
14L
14L
2-3 days in exponential /6 generations /4 generations
Sampling: Sampling: Sampling:
Before adding
culture
Before transfer to
14L culture
Before
starting
bubbling
Before adding
culture
Before transfer to
14L culture
Before
starting
bubbling
Before adding
culture
Final harvest
SEM
Nutrients pH
Salinity
Temperature
DIC/Alk
Nutrient pH
Salinity
Temperature
DIC/Alk
Nutrient pH
Salinity
Temperature
DIC/Alk
Nutrient pH
Salinity
Temperature
PIC
POC
SEM
FRRF
DIC/Alk
Nutrient pH
Salinity
Temperature
DIC/Alk
Nutrient pH
Salinity
Temperature
DIC/Alk
Nutrient pH
Salinity
Temperature
PIC
POC
SEM
FRRF
Proteins for
iTRAQ

25. OA impact on coccolithophores
Subcellular location by protein cluster
Biological process by protein cluster
Jones, Edwards, Skipp, O’Connor, Iglesias-Rodriguez, Proteomics, 2009

26. Improve understanding allows building a range of new models
Alex Kahl, Oscar Schofield and Debora Iglesias-Rodriguez
Photosynthetic
carbon fixation
Carbon Biosynthesis
Carbon Reserves
Light (E)
Nutrients
Low C:N
exudate
High C:N
POC = C
PIC is ½ of the POC
when nutrient saturate
POC can vary with nutrients
PIC is constant Cs
CR : NR
CB : NB
CP : NP
fPB
fPR
fBP
fBS
fRB fN
fE1
fE2

27. Future challenges for the next ten years
Assess long term adaptation of functional groups.
Improve basic knowledge of carbon physiology - adaptation to bicarbonate-rich ocean.
Observations - coupling between biogeochemistry, physiology, and modelling.
Building a global time series to assess changes in chemistry and biology.
Extrapolate from experimental results to natural condition

28. Acknowledgements Richard Bellerby, University of Bergen.
Richard Feely, NOAA, Seattle, U.S.A.
Jean-Pierre Gattuso, Laboratoire de Villefranche, France.
Richard Lampitt, National Oceanography Centre, Southampton, U.K.
John Raven, University of Dundee, U.K.