International HumanDimensions Programme

International Geosphere-Biosphere Programme

World ClimateResearch Programme

An IGBP - IHDP - WCRP Joint ProjectCHALLENGECHALLENGECHALLENGECHALLENGECHALLENGE

THETHETHETHETHECARBONCARBONCARBONCARBONCARBON

THETHETHETHETHECARBONCARBONCARBONCARBONCARBONCHALLENGECHALLENGECHALLENGECHALLENGECHALLENGEAn IGBP - IHDP - WCRP Joint Project

CONTENTSCONTENTSCONTENTSCONTENTSCONTENTS

The Carbon Challange 3

The Science Themes 7

1. Patterns and Variability 7

2. Processes, Controls and Interactions 9

3. Carbon Futures 11

Implementation Strategy 13

Integration and Synthesis 13

Putting the Pieces Together 17

Policy Implications 19

Management Strategy 19

Literature Cited 20

Carbon Meeting Participants 21

2

Contacts:

Interim Executive Officer:

Dr Kathy A. Hibbard

IGBP/GAIM

University of New Hampshire

Morse Hall

Durham, NH USA 03824

Email: kathyh@eos.sr.unh.edu

Nominated Co-Chairs:

Dr Michael Raupach (IGBP)

Email: mike.raupach@cbr.clw.csiro.au

Dr Oran Young (IHDP)

Email: Oran.R.Young@Dartmouth.EDU

Dr Robert Dickinson (WCRP)

Email: robted@eas.gatech.edu

Authors:Kathy Hibbard, Will Steffen, Sam Benedict, Tony Busalachi, Pep Canadell, RobertDickinson, Michael Raupach, Brent Smith, Bronte Tilbrook, Pier Vellinga, OranYoung.

Acknowledgements:This document is a synthesis of the reports and discussions from several internationalplanning meetings held over the past two years. Over 150 carbon-cycle researchersfrom 26 countries were involved (inside back cover). This Prospectus is theforerunner of a detailed scientific framework defining an integrated carbon-cycleresearch project jointly sponsored by IGBP, IHDP and WCRP.

Financial support:European Commission (EC), International Geosphere–Biosphere Programme(IGBP), Netherlands Organization for Scientific Research (NWO), US Departmentof Energy (DOE), US National Aeronautics and Space Administration (NASA), USNational Oceanic and Atmospheric Administration (NOAA), US National ScienceFoundation (NSF), the US Department of the Interior (DOI) and the US Departmentof Agriculture (USDA).

Publishers:International Geosphere Biosphere Programme, Stockholm June 2001

Design and Production:Communications Group, CSIRO Land and Water, Canberra, Australia

3

“Greenhouse gases”, especially carbon dioxide(CO

2), are intimately connected to climate change.

Their rapid increase is challenging the scientificcommunity, policy makers and the public. Topredict future climate change accurately and findways to manage the concentration of atmosphericcarbon dioxide, the processes and feedbacks that

drive the carbon cycle must first be understood.Only then can we project its behaviour into thefuture.

Comparison of contemporary measurements ofatmospheric CO

2 concentration with long-term ice-

core records shows that we have left the regulardomain of glacial–interglacial cycling in whichatmospheric composition and global meantemperatures have varied within well-definedlimits. The global atmospheric CO

2 concentration

is now nearly 100 ppmv higher than theinterglacial maximum; this recent rise is equal tothe entire range of CO

2 concentrations between

glacial minima and interglacial maxima.Atmospheric concentrations of carbon dioxidehave risen to current levels at least ten — possiblya hundred — times faster than at any other time inthe last 420,000 years, and continue to rise sharply(Figure 1, and Falkowski et al. 2000).

The Carbon Challange

(thousands of years before present)

400 300 200 100 0Age of entrapped air

700

650

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CO

co

nce

ntr

atio

n (

pp

mv)

2

Current(2001)

Projected(2100)

Vostok RecordIPCC IS92a Scenario Figure 1. The Vostok ice-core

record for atmospheric CO2

concentration from Petit et al.(1999) and the “business as usual”prediction used in the IPCC ThirdAssessment (Prentice et al. 2001).The current concentration ofatmospheric CO

2 is also indicated.

The recent dramatic increase in atmospheric CO2

is unquestionably the result of human activities. Itis highly likely the observed changes toward awarmer climate over the last century are aconsequence of this increase (Figure 2, andPrentice et al. 2001).

However, the role of human activities in thecarbon cycle is complex. Over the past twocenturies, human activities — industrialproduction, trade and transport, agriculture,forestry and energy use — have grown to amagnitude sometimes equalling or even exceedingglobal-scale natural forces in their influence on thecarbon cycle. Human societies are not just uni-directional drivers of change: they are impacted bychanges in the carbon cycle and climate, and theyrespond to these impacts in ways that feed back to

carbon-cycle dynamics. The Earth’s social,cultural, political and economic systems providethe context in which this complex human–environment system evolves, and in whichattempts by human societies to change the futuredirection of the carbon cycle will be made.

The international scientific community hasresponded to this unprecedented carbon challengeby developing a ten-year Global Carbon CycleJoint Project. The project’s framework provides anintegrated perspective across disciplines as well asnational boundaries. The approach is to accept thathumans and their activities are an integral part ofthe carbon cycle, and that the human–environmentsystem is a single, highly linked and interactivesystem that drives the dynamics of the carboncycle (Figure 3). The goal is to understand the

Figure 2. Variations of the Earth’s surface temperature (1000 to 2100 AD). Data from IPCC Third AssessmentReport (Prentice et al. 2001). Sources of data from 1000–1861 AD — northern hemisphere, proxy data (tree rings,sediment cores, etc.); 1861–2000 AD — global instrumental data; 2000–2100 AD — Special Report on EmissionsScenarios projections.

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1000 1200 1400 1600 1800 2000

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) fr

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Bars show therange in 2001produced byseveral models

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Figure 3. The global carbon cycle fromthree perspectives over time. (a) Duringglacial–interglacial periods and beforesignificant human activities, the globalcarbon cycle was a linked systemencompassing stocks in the land, oceansand atmosphere only. The system was(and still is) controlled or driven throughclimate variability as well as its owninternal dynamics. For instance, theocean carbon system was tightly coupledto air–sea gas exchange as well asphysical and biological “pumps” thattransport carbon. Interactions of the landsurface and atmosphere were driven byland and ecosystem physiology as wellas disturbance. (b) Starting about 200years ago, industrialization andaccelerating land-use changecomplicated the global carbon cycle byadding a new stock — fossil carbon.However, humans did not initiallyperceive that their welfare might beendangered. Regardless of how societyresponds to increased fossil fuel inputsto the atmosphere, or the consequencesof intensification of current land-usepractices, the global carbon cycle hasbeen seriously impacted. (c) Over recentdecades, humans have begun to realizethat changes in climate variability andthe Earth System may significantly affecttheir welfare as well as the functionalityof the global carbon cycle. Thedevelopment and implementation ofinstitutions and regimes to manage theglobal carbon cycle coherently providesa new set of feedbacks in thecontemporary era.

AtmosphericCarbon

LandCarbon

Ocean/coastalCarbon

Disturbance EcosystemPhysiology

SolubilityPump

BiologicalPump

IndustryTransportSystems

Land-useSystems

Ocean-useSystems

Perceptionsof HumanWelfare

Changes in

Instutions &Technologies

FossilCarbon

AtmosphericCarbon

LandCarbon

Ocean/coastalCarbon

DisturbanceEcosystemPhysiology

SolubilityPump

BiologicalPump

IndustryTransportSystems

Land-useSystems

Ocean-useSystems

FossilCarbon

Atmospheric

Carbon

LandCarbon

Ocean/coastalCarbon

Disturbance EcosystemPhysiology

SolubilityPump

BiologicalPump

a

b

c

Carbon stocks

Processes

Control points

on

carbon fluxes

Process links

Carbon flows

Atmosphericand

OceanCirculations

Atmosphericand

OceanCirculations

Atmosphericand

OceanCirculations

underlying mechanisms and feedbacks that controlthe carbon cycle, explain the current patterns ofsources and sinks, and develop plausibletrajectories of the behaviour of the carbon cycleinto the future. The project’s target is to providesocieties with significantly enhanced scientificknowledge of the global carbon cycle on which tobase policy debate and action.

The Global Carbon Cycle Joint Project is co-sponsored by the International Geosphere–Biosphere Programme (IGBP), the InternationalHuman Dimensions Programme on GlobalEnvironmental Change (IHDP) and the WorldClimate Research Programme (WCRP). It isorganized around three fundamental scientific

6

themes that require cooperation and collaborationfrom international and interdisciplinarycommunities:

1. Patterns and Variability

2. Processes, Controls and Interactions

3. Carbon Futures

A fundamental question and a set of supportingquestions guide the work under each theme.Together, the themes provide the framework totackle the critical issues in global carbon-cycleresearch.

Atmosphere Ocean

Land Disturbance

1. Patterns and Variability:What are the geographical and temporalpatterns of carbon sources and sinks?

1.1. How do patterns of carbon sources and sinksvary over time?

1.2. What are the continental and basin-scalespatial patterns of carbon sources and sinks andhow do these relate to carbon storage?

1.3. What is the contribution of human actions,including fossil-fuel burning and land-usepractices, to patterns of carbon sources and sinks?

1.4. How do regional and subregional patterns incarbon flows influence the global carbon budget?

Figure 4 (Upper) Cruise tracks ofoceanographic research ships in the1990s making a global ocean survey ofcarbon tracers for the Joint Global OceanFlux Study (JGOFS) and the WorldOcean Circulation Experiment (WOCE).The carbon-tracer data have been used todetermine the patterns and amounts ofanthropogenic carbon stored in theocean. These tracer data also provide abaseline for determining changes in theocean’s carbon inventories, which willhelp to close the global carbon budget ona scale of decades. (Lower) Surfacemeasurements of the partial pressure ofcarbon dioxide (pCO

2) made on the

cruises shown above were combined withother data collected since 1960 toestimate annual mean ocean–atmospherefluxes for 1995 (kgC m

-2 s

-1 X 10

-9)

(Takahashi et al. 1999).

7

THE SCIENCE THEMESTHE SCIENCE THEMESTHE SCIENCE THEMESTHE SCIENCE THEMESTHE SCIENCE THEMES

Understanding the spatial patterns of carbon fluxeson land and ocean and in the atmosphere isessential to inform the policy process. However,our current knowledge of spatial patterns isuncertain (Peylin et al. submitted). Fossil-fuelemissions have traditionally been concentrated inthe industrialized nations of the north, but thepattern is beginning to shift as developingcountries begin to exploit carbon reserves. There isgood evidence of a northern hemisphere terrestrialsink, although its longitudinal distribution isunknown. The behaviour of the tropical landsurface, affected by both land-use changes andecological processes, is also poorly understood.

Broad-scale patterns of ocean storage and fluxesare emerging (Figure 4); however, large

NP

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SP180 120W 60W 0 60E 120E 180

-2.5 -1.9 -1.2 -0.5 0.2 0.8 1.5 2.2 2.9

uncertainties remain in many regions, includingthe Southern Ocean and coastal zones. Recentpatterns of interannual variability in growth ratesof atmospheric CO

2 point towards changes in

terrestrial metabolism, possibly driven by climatevariability (Figure 5).

The patterns of temporal variability on longer timescales (e.g. decades, centuries) give insights to theprocesses that control fluxes and ultimatelydetermine carbon storage in the ocean, land andatmosphere reservoirs. Decade-scale changes inthe ocean’s carbon storage can now be measured.Together with atmospheric inventories, thesemeasurements will help to close the global budgeton long time scales. The spatial and temporalpatterns across ocean, land and atmosphere areinterlinked and mutually constrained overall by asingle global budget; as patterns in one part of theworld become better known, they help improveknowledge in others.

Source/sink patterns can be estimated by twoapproaches: top-down (e.g. inverse methods,satellite observations), and bottom-up (e.g. forestinventories and surface ocean observations of thepartial pressure of carbon dioxide or pCO2).

Top-down methods largely depend onunderstanding and simulating global andcontinental atmospheric and oceanic transport aswell as carbon distribution in the atmosphere andoceans. Our understanding of large-scale transport,however, is incomplete and limits an accurateassessment of the patterns of global carbon stocksand flows.

Bottom-up methods also have large uncertainties;for example, the drivers for human decisions onland-use practices and energy systems,measurement of changes in soil carbon over timeand, in oceans, the aggregation of hundreds ofthousands of point measurements taken over

Figure 5. Annual changes in the growth rate of atmospheric CO2 from the Mauna Loa Observatory (Scripps — solidblue line, 1957 to present; and National Oceanic/Atmospheric Administration (NOAA) — dotted blue line, 1977 topresent), Cape Grim (solid green line, 1991 to present), annual fossil fuel emissions (solid red line) and globalaverage from NOAA (dotted orange line). Note the large peaks in the interannual growth rate coinciding with ElNiño events (lite bars), highlighting the influence of variable climate modes on the Earth’s metabolism.

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several years under varying conditions.Discrepancies among source/sink distributionsestimated by direct human, ocean and landobservations and inferred from atmosphericinverse calculations must be resolved beforeglobal and regional carbon budgets can be robust.

Sample Research Priorities:

● To resolve the longitudinal distribution of thenorthern hemisphere land-sink and elucidate therole of the terrestrial tropics in the global carboncycle.

● To quantify variability in ocean sources andsinks, and determine the role of the SouthernOcean and coastal zones in the carbon cycle.

● To quantify the current distribution ofanthropogenic carbon in the ocean and therelationship to air–sea flux.

● To distinguish between the roles of naturaldisturbance and land-use and their legacies indetermining the current spatial patterns ofterrestrial sinks.

● To quantify the differences in patterns offossil-fuel use among industrial sectors and amongdistinct regions within individual countries.

● To resolve the role of climate variability indriving the observed pattern of interannualvariability in the increase of atmospheric CO

2.

2. Processes, Controls andInteractions:What are the control and feedbackmechanisms — both anthropogenic and non-anthropogenic — that determine thedynamics of the carbon cycle on scales ofyears to millennia?

2.1. What mechanisms controlled paleo- and pre-industrial concentrations of atmospheric CO2?

2.2. What mechanisms control current terrestrialand oceanic carbon fluxes?

2.3. What mechanisms control anthropogeniccarbon fluxes and storage?

2.4. How do feedback mechanisms operate tomagnify or dampen both anthropogenic and non-anthropogenic carbon fluxes?

To explain the current distribution of carbonsources and sinks (Theme 1) and to developplausible trajectories of future carbon dynamics(Theme 3), a clearer understanding of criticalprocesses and control points is required(Theme 2).

The mechanisms and feedbacks that control thelong-term cyclical pattern of atmospheric CO2variation shown in the ice-core records are stilllargely unknown. The need to understand these isbecoming increasingly urgent as we move rapidlyout of this previously tightly bounded domain(Falkowski et al. 2000, Figure 1).

In the contemporary carbon cycle, an adequateunderstanding of the mechanisms behind a numberof critical processes still eludes us: the proximateand ultimate drivers of changes in industrialsystems and institutional regimes; the interplaybetween land-use, ecosystem physiology anddisturbance that controls carbon flows in and outof land systems; the lateral flows and storage ofcarbon across landscapes and into the coastal–open ocean zones; and the biological, chemicaland physical interactions that move carbonthrough the atmosphere / upper-ocean / deep-oceansystems.

9

Figure 6. Anthropogenic mechanisms that affect atmospheric carbon fluxes. The main human inputs to carbonemissions are industry, deforestation and transport. Human activities that sequester carbon or reduce emissionsinclude forest plantations and alternative energy sources such as wind and solar power.

10

Elucidating how carbon-cycle processes interactwith each other and with climate is an even largerchallenge. Since human activities have becomeimportant processes in carbon-cycle dynamics(Figure 6), any likely responses of human systemsto changing stocks of carbon must be incorporatedinto the characterization of the overall systemdynamics. Especially important is the sequence ofprocesses that link the perception of climatechange and its impacts to changes in institutionalregimes and eventual changes in industrial systemsand land-use practices (Figure 3b,c).

Two other critical issues are: (i) the response ofthe terrestrial carbon cycle to changingtemperature and precipitation through changes ingrowth, respiration, and disturbances such as fires;and (ii) the response of the ocean carbon cycle tochanges in CO2 solubility associated withchanging temperature and increases inatmospheric/surface ocean CO2, and its responseto climate-related changes in ocean circulation andecosystem dynamics.

Sample research priorities:

● To understand the controlling features andsimulate the temporal dynamics of the glacial–interglacial carbon-climate system.

● To understand the mechanisms that controlflows of carbon between (i) land and atmosphericstocks; (ii) ocean and atmospheric stocks; and (iii)land and ocean stocks (coastal zones).

● To determine the role of oceanic andatmospheric transport in carbon-cycle dynamics.

● To explain and explore the relative importanceof the drivers in the spatial and temporal variationsin the intensity of humans’ energy use.

● To determine how public and private activitiesand their interactions drive rates of deforestationand influence land-use practices.

3. Carbon Futures:What are the likely dynamics of the globalcarbon cycle into the future?

3.1. Are current terrestrial carbon-sinks permanentfeatures of the biosphere; are they likely todisappear; or even become sources in the future?

3.2. How will the physical and biological driversof carbon uptake in the ocean evolve over the nextcentury and influence ocean storage?

3.3. What are plausible trajectories of carbonfluxes associated with industrial, commercial,transport and residential systems, as well as land-use practices and land-cover changes?

3.4. How are humans responding, and how willhumans respond in the future, to the challenge ofmanaging the carbon cycle?

The ultimate goal of carbon-cycle research is tounderstand the system well enough to makereliable projections of carbon-cycle dynamics intothe future. This requires an integration of morefocused work on processes and mechanisms andon patterns and variability to develop system-leveltools that can simulate overall carbon-cyclebehaviour over decades and centuries.

Several aspects of the system’s behaviour arecritical. The “industrial transformations–institutional challenges” complex is the dominantsubsystem at present. How this complex developsover the next several decades will largelydetermine the concentration of atmospheric CO2.The long-term atmospheric concentration of CO2also depends on the continued operation of twolarge biophysical subsystems—the ocean and landsinks. Some projections suggest that in thiscentury the land sink may saturate or even turninto a source (Figure 7), and the ocean’s capacityto take up atmospheric CO2 may also weakensignificantly.

Because the carbon cycle operates as a singleinterlinked system, the timing and interactions ofthese large subsystems are crucial. The carboncycle, and the Earth System as a whole, couldexhibit instabilities and/or multiple equilibriumstates on scales of decades to centuries. If we areclose to critical thresholds in the cycle, the 11

timing—not just the magnitude—of changes insubsystems can be the determining factor. Forexample, if the ocean’s uptake capacity is changedand land sinks weaken significantly or saturatelater this century, heavy cuts in fossil-fuelemissions at that time may be too late to avoid achange in the state of the Earth System. Earliercuts in emissions might, on the other hand, preventthe Earth System from crossing a criticalthreshold. The only way to know whether we areapproaching such a threshold is to develop a soundprognostic capability based on an integratedsystem-level understanding of the carbon cycle.

Sample research priorities:

● To simulate the transition from the pre-industrial to the current state of the carbon cycle asa basis for predicting future mechanisms andenvironmental trajectories.

● To develop regional scenarios of the carboncycle that can also be used to develop andconstrain the global carbon budget.

● To identify the forces that will control theprospects for decarbonization of industrialeconomies over the next 10 to 50 years.

● To determine the prospects for success of aglobal-climate regime and analyze alternativeinstitutional arrangements that might moreeffectively reduce anthropogenic emissions ofCO2.

● To determine whether the strength and patternsof terrestrial and ocean sinks will be changed andif so, when and why.

Figure 7. Results from six Dynamic Global Vegetation Models predicting Net Terrestrial Ecosystem Productivityfrom 1860 through to 2100 with elevated atmospheric CO2 and climate change. Shaded area in grey represents themodels’ results for elevated CO2 only. Note the general agreement between the terrestrial models from the late1800s to 2050, suggesting that the land surface increasingly acts as an sink. After 2050, the models diverge.However, all suggest that over time the terrestrial biosphere loses its capacity to absorb carbon. The carbon sinkbecomes saturated.

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1850 1900 1950 2000 2050 2100

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2

To make significant progress in answering thesefundamental questions over the next decade is aformidable challenge. Much research on the globalcarbon cycle is already under way or planned; thestrategy of the Global Carbon Cycle Joint Projectis to build on this work. However, this research islargely not integrated or coordinated, which resultsin large gaps in some areas and duplication inothers. By developing a single, unified, mutuallyagreed framework and the mechanisms forexchanging information, the Project aims toidentify research gaps and lessen redundancy ofeffort and inefficiency in the use of researchresources.

The Project’s strategy is thus to coordinatenational and disciplinary efforts within theinternational and multidisciplinary jointframework to tackle global-scale carbon-cyclequestions that cannot be answered otherwise. Inturn, analytic planning that takes a global view ofthe carbon system will assist national and regionalefforts to constrain their budgets and identifyfeedbacks and teleconnections that extend beyondtheir geographical boundaries. In addition, thejoint project will explore new emerging propertiesand pathways of the carbon cycle under futurecombinations of environmental factors and humanbehaviour.

The first element of the Project’s implementationstrategy is to build integration and synthesis intothe framework from the outset, rather than toattempt it after the field work and case studies arecomplete. It will bring pieces of research togetherto explore the major questions rather than splittingthem into finer-scale fragmented research projects.

The second element of the strategy is to contributeto the coordination and development of carbon-cycle science programmes at the international,regional and national levels, with the goal ofanswering the three fundamental questions.

Integration and Synthesis

A central challenge in carbon-cycle research is tosynthesize the massive array of differentmeasurements and results of case and processstudies into a single, internally consistentframework. The Global Carbon Cycle JointProject proposes to use a “multiple-constraint”synthesis approach, which combinesmeasurements and models. In essence, it integratesobservations (remotely sensed and in situ), models(diagnostic and predictive), process andmanipulative experiments and case studies toconstrain the global carbon balance, together withregional and local budgets. It does so by using datastreams from both the human and natural sciencesto constrain model parameters to optimal values,and thus to infer complete space–timedistributions of carbon stocks and flows, or otherdesired parameters (Figure 8).

Other integration and synthesis tools needed towork towards answering the fundamentalquestions include interdisciplinary workshopstackling focused questions; linking of models fromthe human and natural sciences and integratingtheir associated data sets; constructing globalcarbon budgets at regular intervals; modellingcomparisons and tests against data; andassimilating and synthesizing internationalobservational data sets.

Extending Observations

Observations of carbon-cycle dynamics are afundamental component of attempts to understandthe carbon cycle. Our first awareness of theseriousness of the “carbon challenge” came fromthe careful, long-term measurement of atmosphericCO2 at the Mauna Loa Observatory in Hawaii(Keeling et al 1995). The Global Carbon CycleJoint Project will need an expanded and improvedglobal network of carbon and related tracerobservations. To achieve this will requirecomparisons and calibration of observations fromdifferent instruments and techniques; the rationalextension of atmospheric CO2, carbon isotope andoxygen measurements; the continuation andextension of surface ocean pCO2 and time-series

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IMPLEMENTIMPLEMENTIMPLEMENTIMPLEMENTIMPLEMENTAAAAATION STRATION STRATION STRATION STRATION STRATEGYTEGYTEGYTEGYTEGY

measurements; the enhancement of carbon-tracermeasurements along repeat ocean sections; thedevelopment of satellite measurements of CO2;the construction of spatially explicit humandimensions data sets and their integration withbiophysical data; the description andquantification of land-cover change; and thescaling of data from process studies throughregions to the globe.

Extending Case and Process Studies

Case and process studies provide the fundamentalbuilding blocks of mechanistic knowledgeessential for system-level understanding. Forexample, a major challenge is to build upon andmove beyond case studies and test hypothesesabout the interactions of land-use, demographicchange and economic development. The14

Figure 8. Measuring the carbon metabolism of the terrestrial biosphere: techniques andresults (Canadell et al. 2000).

Figure 9. Decarbonising the energy system. Global environmental changes that are driven primarily by socio–economic, demographic, institutional and technological systems compel societies to satisfy human needs. However,changes in these systems are initiated only when the perceptions of current or future needs are threatened. Meetingcurrent and future energy demands while minimizing global environmental impacts is a challenge for a globalsociety. It requires major transformations of energy systems in both production and consumption, and the incentivestructures that shape the interaction of the two. Possible options for transformations include a shift to renewableenergies, introduction of CO2 emissions trading, and changes in lifestyle and values. (Figure adapted from Vellingaand Wieczorek, 2000).

15

DRIVING FORCES FORGLOBAL ENVIRONMENTAL CHANGE

Socio-economicDemographicInstitutionalTechnological

CONCERN ABOUT FULFILLING FUTURE NEEDS

EXPLORING SYSTEMTRANSFORMATIONSProduction systemsConsumptions systemsIncentives that shaperelations between systems

DELINKINGECONOMIC GROWTH

FROM INCREASEDENVIRONMENTAL

PRESSURE

Production / Fuels Incentive - Institutions ConsumptionRenewable energies(eg. solar, biomass, wind)

'Zero' emissions vehiclesand power plants

CO sequestration2

CO emission tradingGreen taxesLabellingStandards

2 NeedsLifestylesValuesPreferences

mechanisms by which industrial systems aretransformed will provide insights into whether,and when, energy systems can be “decarbonized”(Figure 9). Case studies on institutionaldevelopment and evolution will provide essentialunderstanding of how human societies areresponding to the carbon challenge (Figure 10).

On the biophysical side, a variety of processstudies is needed to tackle specific questions, fromthe ways in which ocean circulation and nutrientavailability constrain ocean-carbon uptake, to theresponse of soil carbon to changing temperatureand moisture.

16

Figure 10. Institutions and their effects on the carbon cycle. (Adapted from Young et al. 1999).

Local, Regional, National, International and Global

INSTITUTIONSSystems of Property Rights (e.g. Private Property) Environmental Regimes (e.g. Climate Regime)

INSTITUTIONAL CAUSES

Weak or Non-Existent Incentives ToControl:

* Greenhouse Gas Emissions * Soil Erosion * Depletion Of Resources

HUMAN ACTIONS

Energy Production (e.g. Fossil Fuel Combustion)

Land Use Practices (e.g. Deforestation, Land Clearing For Agriculture)

OTHER CAUSES

Socioeconomic (e.g. Diffusion Of New Technologies) Biogeophysical (e.g. Variations In Solar Activity)

ENVIRONMENTAL CHANGE

Climate Change & Variability (e.g. Increased Temperature, Rise Of Sea Level)

INSTITUTIONAL RESPONSES

Technology Sharing (e.g. Energy-Efficient Production Systems) Regime Alterations Such As The Kyoto Mechanisms:

* Clean Development Mechanism * Emissions Trading * Joint Implementation

Putting the Pieces Together

The three co-sponsors of the Global Carbon CycleJoint Project are already carrying out or starting upa wealth of carbon-cycle research, providing manyof the pieces required for the framework. Theexamples given below are representative ratherthan exhaustive.

IGBP has a long-standing suite of carbon-researchactivities. They range from iron fertilizationexperiments in the ocean; experimental studies ofterrestrial ecosystem response to warming andelevated CO2; budget approaches to coastal-zonecarbon fluxes; and comparisons of a wide range ofmodels related to the carbon cycle.

IHDP has initiated a suite of key carbon-relatedactivities, including a flagship project oninstitutional approaches to managing the carboncycle; research on industrial transformations andthe decarbonization of energy systems; and theimplications for human security of changes incarbon-cycle dynamics.

WCRP provides the modelling tools for climatevariability and change essential for understandinginterannual to intercentury variability in thecarbon cycle; the strong control of oceanic andatmospheric circulation over carbon transport andstorage; and links between the carbon andhydrological cycles.

The three programmes already work together onsome areas of carbon-cycle research. For example,WCRP and IGBP work closely together on climatevariability and have established a programme ofocean-carbon measurements. The IHDP and IGBPjointly sponsor a project on land-use and land-cover change, including its implications for thecarbon cycle.

National and regional carbon research programmeswill also contribute strongly to the Project.Conversely, the enhanced global understandingfrom the Project has considerable potential to feedinto national and regional programmes byproviding a common global context within whichto study particular aspects of the carbon cycle.

National Projects:The United States and Australia are examples ofcountries with well-developed science plans fornational-level carbon-cycle projects focused

primarily on terrestrial uptake, and are beginningto implementt them. Other national-level projectsare being developed around the world, from Japanto the Ukraine, Sweden and China.

Regional Projects:CarboEurope is an extensive cluster of projects inWestern Europe with a regional-scale approach tocarbon research. The Large-Scale Biosphere–Atmosphere Experiment in Amazonia, althoughnot focused solely on the carbon cycle, providescomplementary regional-scale information on thecarbon dynamics in a developing country.

Key International Linkages:Global observations are an important componentto understanding the carbon cycle. Linking globalobservations with models and experiments are keyto interpreting and predicting the past, current andfuture dynamics of the global carbon cycle. Thechallenge of obtaining and disseminating globalcarbon-cycle observations has been taken up bythe Integrated Global Observing StrategyPartnership (IGOS-P). IGOS-P is a consortium ofspace agencies, in situ observation organisations,and international research programmes. Buildingon a first phase of terrestrial-carbon observations,IGOS-P is now working on a flexible and robuststrategy for acquiring international, integrated,global carbon observations over the next decade.The aim is to build a globally consistent networkof observations from both space and Earthplatforms. The partnership is being coordinated insynchrony with the development of the GlobalCarbon Cycle Joint Project. The challenge ofdeveloping an integrated global system of bothremotely sensed and in situ observations willundoubtedly accelerate the development of newobservation technologies and data-handlingsystems within the context of Earth SystemScience and the global carbon cycle.

Each of the activities or projects mentioned above,and many others, provides essential pieces of thepuzzle needed to understand the global carboncycle. The Joint Project provides a frameworkwithin which to put these pieces together and, withnew work to fill gaps, build a coherent globalpicture. Finally, the Project will also encourage theexploration of new issues and future pathways ofthe carbon cycle that have not yet been envisaged(Figure 11).

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Figure 11. Conceptual diagram showing the relationship between the Global Carbon Cycle Joint Project and othergroups involved in carbon science. Much of the research in the Project will come from existing and planned researchin the three sponsoring global environmental-change programmes—IGBP, IHDP and WCRP. In addition, nationaland regional carbon programmes (e.g. CarboEurope, Carbon Australia, US Carbon Cycle Initiative) will contributevaluable research. The Global Carbon Cycle Joint Project provides a framework for integrating these many pieces ofcarbon science and for initiating new work where gaps are found. It will also work closely with the Integrated GlobalCarbon Observing Strategy being developed under the auspices of IGOS-P, and interact with the assessmentcommunity (e.g. Intergovernmental Panel on Climate Change, IPCC), the national and international policycommunity, and non-governmental organisations (NGOs).

I H D P

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Figure 12. Institutions in action. The Third Session ofthe UNFCCC Conference of the Parties in Kyoto in1997. (Photo courtesy of IHDP).

POLICY IMPLICAPOLICY IMPLICAPOLICY IMPLICAPOLICY IMPLICAPOLICY IMPLICATIONSTIONSTIONSTIONSTIONS

MANMANMANMANMANAAAAAGEMENT STRAGEMENT STRAGEMENT STRAGEMENT STRAGEMENT STRATEGYTEGYTEGYTEGYTEGY

The Global Carbon Cycle project is a joint ventureinvolving three equal partners: the InternationalGeosphere–Biosphere Programme, theInternational Human Dimensions Programme, andthe World Climate Research Programme.

The project will be managed by a ScientificSteering Committee co-chaired by three people(one from each partner programme) who arejointly responsible for the management of project.To complete the committee, up to five additionalmembers will be selected by each programme.

Staff support during the planning stage of theGlobal Carbon Cycle Joint Project was providedby IGBP’s Global Analysis, Integration andModelling project (GAIM). Dr K Hibbard ofGAIM served as Executive Officer during thepreparation of this document.

Staff support for the implementation of the projectwill be provided by the three sponsoringprogrammes.

The ultimate goal of the Global Carbon CycleJoint Project is to provide societies with thescientific knowledge on which to base theirdiscussions, debates and actions to influence thefuture dynamics of the carbon cycle. Althoughmuch excellent carbon-cycle research is beingcarried out at national and regional scales, itsgeographical focus prevents it from being acceptedby all countries as a “common scientific currency”that can inform discussion and decision in a sound,objective fashion. The need for an internationalapproach to such a knowledge base is undeniable(Figure 12).

It is also important to acknowledge therelationship of a research-driven activity (GlobalCarbon Cycle Joint Project) to assessmentactivities such as those of the IntergovernmentalPanel on Climate Change (IPCC), and to thedevelopment of a global, carbon-observing systemthrough IGOS-P. The importance of this trio oflinked carbon-cycle activities—research,assessment and observation—cannot be

overstated. Together they form an internationallycoordinated attack on a major globalenvironmental problem, and are perhaps the firstsystematic attempt to provide a comprehensiveknowledge base for the ongoing management of amajor Earth System function.

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Petit, J.R., Jouzel, J., Raynaud, D., Barkov,N.I.,Barnola, J.-M., Basile, I., Benders, M.,Chappallaz, J., Davis, M., Delaygue, G., Delmotte,M., Kotlyakov, V.M., Legrand, M., Lipenkov, V.Y.,Lorius, C., Pépin, L., Ritz, C., Saltzman, E., andM. Stievenard. 1999. Climate and atmospherichistory of the past 420,000 years from the Vostokice core, Antartica. Nature 399:429-436.

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Intergovernmental Panel on Climate Change(IPCC) Third Assessment Report. eds: Houghton,JT, Yihui, D. Cambridge University Press,Cambridge, in press.

Schimel, D.S., House, J.I., Hibbard, K.A.,Bousquet, P., Ciais, P., Peylin, P., Braswell, B.H.,Apps, M.J., Baker, D., Bondeau, A., Canadell, J.,Churkina, G., Cramer, W., Denning, A.S., Field,C.B., Friedlingstein, P., Goodale, C., Heimann, M.,Houghton, R.A., Melillo, J.M., Moore III., B.,Murdiyarso, D., Noble, I., Pacala, S.W., Prentice,I.C., Raupach, M.R., Rayner, P.J., Scholes, R.J.,Steffen, W.L., and C. Wirth. 2001. Recent patternsand mechanisms of carbon exchange by terrestrialecosystems.Nature submitted.

Takahashi, T, Wanninkhof, RH, Feeley, RA,Weiss, RF, Chipman, DW, Bates, N, Olafsson, J,Sabine, C, Sutherland, SC. 1999. Net sea–air CO2flux over the global oceans: An improved estimatebased on the sea–air pCO2 difference. In:Proceedings of the 2nd International SymposiumCO2 in the Oceans, Tsukuba, Jan. 1999. pp. 9–15.

Vellinga, P, and Wieczorek, A. 2000. IGBP/IHDP/WCRP Joint Carbon Cycle Project: Industrialtransformation research questions relevant for thisjoint natural–social sciences project. IHDP Reportfrom Amsterdam.

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LITERALITERALITERALITERALITERATURE CITEDTURE CITEDTURE CITEDTURE CITEDTURE CITED

Francis J Ahern, CanadaLarry Akinson, USAGeorgii Alexandrov, JapanArthur Alexiou, FranceKeith Alverson, SwitzerlandDiogenes Alves, BrazilBob Anderson, USAMike Apps, CanadaO. Arino, ItalyBeatrice Baliz, NorwayAlan Barr, CanadaMichael Bender, USAWu Bingfang, ChinaBert Bolin, SwedenRobert Braswell, USAFrancis Bretherton, USAWendy Broadgate, SwedenClaus Bruening, BelgiumKen Caldeira, USAJosep (Pep) Canadell, AustraliaDoug Capone, USAMary-Elena Carr, USAAlain Chedin, FranceArthur Chen, TaiwanJing Chen, CanadaPhilippe Ciais, FranceJosef Cihlar, CanadaMartin Claussen, GermanyPeter Cox, UKWolfgang Cramer, GermanyQin Dahe, ChinaHein de Baar, NetherlandsGerard Dedieu, FranceRuth Defries, USAScott Denning, USARay L. Desjardins, CanadaAndrew Dickson, USALisa Dilling, USACraig Dobson, USAHan Dolman, NetherlandsHugh Ducklow, USASyma Ebbin, USAJim Ehrlinger, USAIan Enting, AustraliaPaul Falkowski, USAChris Field, USARoger Francey, AustraliaLouis Francois, BelgiumRoger Francois, USAAnnette Freibauer, GermanyPierre Friedlingstein, FranceInez Fung, USAAnver Gahzi, BelgiumVéronique Garçon, FranceRoy Gibson, FranceRené Gommes, ItalyDavid Goodrich, USAJames Gosz, USAMike Goulden, USATom S Gower, USA

John Grace, UKWatson Gregg, USANicolas Gruber, USAKevin Gurney, USAMykola Gusti, UkraineNeil Hamilton, GermanyDennis A Hansell, USARoger Hanson, NorwayMartin Heimann, GermanyBarry Heubert,Kathy Hibbard, USANicolas Hoepffner, ItalyTony Hollingsworth, UKMaria Hood, FranceRichard Houghton, USAGeorge Hurtt, USATamotsu Igarashi, JapanGen Inoue, JapanRob Jackson, USAFortunat Joos, SwitzerlandPavel Kabat, NetherlandsMichael Keller, USAHaroon S Kheshgi, USADave Knapp, USAChristian Koerner, GermanySwami Krishnaswami, IndiaThelma Krug, GermanyM Dileep Kumar, IndiaSandra Lavorel, FranceCindy Lee, USARik Leemans, NetherlandsCorinne LeQuéré, GermanyRicardo Letelier, USAIngeborg Levin, GermanySune Linder, SwedenKarin Lochte, GermanySabine Lutkemeier, GermanyErnst Maier-Reimer, GermanyGregg Marland, USAJohn Marra, USAPhillippe Martin, FranceLiliane Merlivat, FrancePatrick Monfray, FranceBerrien Moore III, USADaniel Murdiyarso, IndonesiaRanga Myneni, USAPascal Niklaus, SwitzerlandIan Noble, AustraliaCarlos Nobre, BrazilYukihiro Nojiri, JapanRich Norby, USADennis Ojima, USADick Olson, USAJames Orr, FranceSteve Pacala, USADiane Pataki, USAJoyce E. Penner, USAJoão Santos Pereira, PortugalLou Pitelka, USAStephen Plummer, UK

Carbon Meeting PCarbon Meeting PCarbon Meeting PCarbon Meeting PCarbon Meeting ParararararticipantsticipantsticipantsticipantsticipantsChristopher Potter, USAMichael Prather, USAColin Prentice, GermanyNavin Ramankutty, USAIchtiaque Rasool, FranceMichael Raupach, AustraliaDominique Raynaud, FrancePeter Rayner, AustraliaDonald Rice, USAAida F Ríos, SpainPaul Robbins, USAHumberto Rocha, BrazilEugene A. Rosa, USASteve Running, USAChristopher Sabine, USADork Sahagian, USAToshiro Saino, JapanScott Saleska, USABernard Saugier, FranceJohn Schellnuber, GermanyReiner Schlitzer, GermanyRobert J (Bob) Scholes, South AfricaDetlef Schulz, GermanyUwe Send, GermanyEmanuel A Serrao, BrazilSteven Shafer, USAAnatoly Shvidenko, AustriaBrent Smith, USAPete Smith, UKSteve Smith, USAAllen M Solomon, USAElliott Spiker, USAWill Steffen, SwedenGerard Szejwach, GermanyArnold H Taylor, UKBronte Tilbrook, AustraliaRichard Tol, GermanyJohn Townshend, USANeil BA Trivett, CanadaJeff Tschirley, ItalyRiccardo Valentini, ItalyDouglas Wallace, GermanyVirginia M Walsh, USARik Wanninkhof, USAAndrew Watson, UKDiane E Wickland, USAF Ian Woodward, UKYoshiki Yamagata, JapanYoshifumi Yasuoka, JapanOran Young, USA

Meeting Support:

Jennifer Boles, USAAlexandra Correia, PortugalChantal Le Scouarnec, FrancePatricia Dolores Melo, PortugalSofia Roger, Sweden 21