Post on 20-Dec-2015
General Scheme for Working Group Objectives
Physiological/Biogeochemical ResponsesOrganisms and Communities
Ecosystem EffectsHow would changes in populations of calcifying
organisms affect ecosystems?
Exp
erim
enta
l man
ipu
lati
on
s
Organism EffectsHow would the response affect species?
Earth System FunctioningCarbon cycle, CO2 uptake, feedbacks
Mo
del
ing
Pal
eore
cord
s
Mo
nit
ori
ng
majority of studies
Pressing Questions Session 1Ecophysiological Responses of Calcifiers to Increased
pCO2 - Current Knowledge and Pressing QuestionsControls on calcification (only briefly review these if necessary)
Taxonomic differencesTechnological considerationsStandardization of measurements
Controls on calcification (only briefly review these if necessary)
Taxonomic differencesTechnological considerationsStandardization of measurements
What is evidence that CO2 chemistry controls calcification in nature?
Is calcification response to CO32– linear, or asymptotic?
What are the relative roles of HCO3– and CO3
2– in the calcification process?
What is the relationship between photosynthesis and calcification?
What is the impact of temperature/light/nutrients on calcification?
Pressing Questions Session 1Ecophysiological Responses of Calcifiers to Increased
pCO2- Current Knowledge and Pressing Questions
Controls on calcification
Taxonomic differences
Technological considerationsStandardization of measurements
• Do we need experimental data from more species, or across more groups?
• Can we expect calcifiers to adapt to rising pCO2 and if so, by what mechanisms? Over what time scales?
Pressing Questions Session 1Ecophysiological Responses of Calcifiers to Increased
pCO2- Current Knowledge and Pressing Questions
Controls on calcification
Taxonomic differencesTechnological considerations
Standardization of measurements
• What are the technological capabilities and challenges for CO2 system measurements and calcification measurements?
• What questions are best addressed in field studies, lab studies, or mesocosms?
• What questions can be addressed through modeling? • What important ecophysiological parameters are not currently
included in models because of lack of data?
Pressing Questions Session 1Ecophysiological Responses of Calcifiers to Increased
pCO2- Current Knowledge and Pressing Questions
• What are the advantages/disadvantages of existing research designs, sampling, manipulation of CO2 chemistry, etc?
• Can we recommend “standards” within this arena? • How can different measures of calcification be
related/standardized?
Controls on calcification
Taxonomic differencesTechnological considerationsStandardization of measurements
Pressing Questions Session 1Ecophysiological Responses of Calcifiers to Increased
pCO2- Current Knowledge and Pressing Questions
Pressing Questions Session 2Ecosystem Response to Elevated pCO2: Existing and Future Filed Monitoring and
Experimental Research
Ecological responses
Regional considerations
Ecological responses
Regional considerations
• Will calcifying organisms be outcompeted by noncalcifiers? If so, What impacts to ecosystem structure and function might occur?
• What changes, if any, may occur in food webs and other species interactions?
• How could such ecological responses affect the cycling of organic and inorganic C?
Pressing Questions Session 2Ecosystem Response to Elevated pCO2: Existing and Future Field Monitoring and
Experimental Research
• What information can be obtained by conducting studies in regions with natural variability in pCO2?
• What regions would be most promising in terms of better characterizing CO2-chemistry environment?
• Which regions do models indicate will likely experience the greatest changes in seawater carbonate chemistry?
• Over what time scales?
Ecological responses
Regional considerations
Pressing Questions Session 2Ecosystem Response to Elevated pCO2: Existing and Future Field Monitoring and
Experimental Research
Pressing Questions Session 3
• What experimental designs are needed to address the pressing questions?
• What can be done now, with existing technology (both pelagic and neritic regions)?
• What can be done within next 5-10 years, with emerging technology? • What are the coastal needs/concerns, versus those of open ocean
(e.g., precision, contamination, etc.)? • Can we capitalize on existing monitoring/research efforts to obtain
more/better data? where? how? • How can we measure dissolution within the water column and within
sediments? What is the role of dissolution in buffering the system?• How can we focus paleoclimatology, isotopic analyses, etc. to
address questions about CO2 affects on calcification?
• How can remote sensing be integrated into the overall monitoring and experimental designs? Are there pressing needs to develop new remote sensing technology?
Experimental Design
Pressing Questions Session 4
• What are the priorities in modeling the CO2-calcification questions? (carbon cycle? ecosystem/community interactions? physiological modeling? sediment/water interactions? etc.)?
• What important questions can be addressed with existing models? Which will require model development?
• Which modeling questions would be well constrained versus poorly constrained by existing data?
Modeling
Ecology•Habit & domain•Response to nutrient, light, temperature changes•Biodiversity•Food webs & species interactions•Capacity to adapt to elevated pCO2
Calcification•Production cycle/generation times•Mineralogy•CaCO3 production and net accumulation
Carbonate System Behavior•pCO2 variability •Influence of sedimentary processes
Carbon Cycling•Role in the carbon cycle
Planktonic versus Benthic Calcifiers
Possible Functions of CaCO3 in OrganismsFunction Planktonic BenthicProtection All groups All groups
Buoyancy regulation coccolithophores foraminifera
Light modification coccolithophores corals
Provide protons for conversion of HCO3
– to CO2 for photosynth.coccolithophores calcareous algae?
Facilitate bicarbonate-based photosynthesis
coccolithophores
Aid in capture of prey foraminifera
Reproduction pteropods corals?
Prevention of osmotically induced volume changes
coccolithophores
Extension into hydrodynamic regime
corals, calc. algae, bryozoans
Anchoring to substrate corals, calc. algae, bryozoans
Competition for space corals, calc. algae, bryozoans
mm
Ecosystem Effects
experimentalmanipulations
Earth SystemCarbon Cycle
modeling
paleorecords
monitoring
103
102
101
100
10–1
10–2
10–3
10–4
10–5
10–6
10–4 10–3 10–2 10–1 100 101 102 103 104 105
ywh d mo
km
m
cm
Time (days)
Sp
ace
(km
)
m
Physiology
Organism
remote sensing