THETHE CARBONCARBONCARBON CHALLENGECHALLENGE An IGBP - IHDP - WCRP Joint Project International Human International Geosphere- World Climate Dimensions Programme Biosphere Programme Research Programme THETHE CARBONCARBON CHALLENGECHALLENGE An IGBP - IHDP - WCRP Joint Project CONTENTS 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 Contacts: Interim Executive Officer: Dr Kathy A. Hibbard IGBP/GAIM University of New Hampshire Morse Hall Durham, NH USA 03824 Email: [email protected] Nominated Co-Chairs: Dr Michael Raupach (IGBP) Email: [email protected] Dr Oran Young (IHDP) Email: [email protected] Dr Robert Dickinson (WCRP) Email: [email protected] Authors: Kathy Hibbard, Will Steffen, Sam Benedict, Tony Busalachi, Pep Canadell, Robert Dickinson, Michael Raupach, Brent Smith, Bronte Tilbrook, Pier Vellinga, Oran Young. Acknowledgements: This document is a synthesis of the reports and discussions from several international planning meetings held over the past two years. Over 150 carbon-cycle researchers from 26 countries were involved (inside back cover). This Prospectus is the forerunner of a detailed scientific framework defining an integrated carbon-cycle research 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 Department of Energy (DOE), US National Aeronautics and Space Administration (NASA), US National Oceanic and Atmospheric Administration (NOAA), US National Science Foundation (NSF), the US Department of the Interior (DOI) and the US Department of Agriculture (USDA). Publishers: International Geosphere Biosphere Programme, Stockholm June 2001 Design and Production: Communications Group, CSIRO Land and Water, Canberra, Australia 2 The Carbon Challange drive the carbon cycle must first be understood. Only then can we project its behaviour into the future. Comparison of contemporary measurements of atmospheric CO2 concentration with long-term ice- core records shows that we have left the regular domain of glacial–interglacial cycling in which atmospheric composition and global mean temperatures have varied within well-defined limits. The global atmospheric CO2 concentration is now nearly 100 ppmv higher than the interglacial maximum; this recent rise is equal to “Greenhouse gases”, especially carbon dioxide the entire range of CO2 concentrations between glacial minima and interglacial maxima. (CO2), are intimately connected to climate change. Their rapid increase is challenging the scientific Atmospheric concentrations of carbon dioxide community, policy makers and the public. To have risen to current levels at least ten — possibly predict future climate change accurately and find a hundred — times faster than at any other time in ways to manage the concentration of atmospheric the last 420,000 years, and continue to rise sharply carbon dioxide, the processes and feedbacks that (Figure 1, and Falkowski et al. 2000). 700 Projected (2100) 650 600 Vostok Record 550 IPCC IS92a Scenario Figure 1. The Vostok ice-core record for atmospheric CO2 500 concentration from Petit et al. (1999) and the “business as usual” 450 prediction used in the IPCC Third Assessment (Prentice et al. 2001). The current concentration of 400 atmospheric CO2 is also indicated. Current (2001) 350 2 CO concentration (ppmv) 300 250 200 150 400 300 200 100 0 Age of entrapped air (thousands of years before present) 3 The recent dramatic increase in atmospheric CO2 carbon-cycle dynamics. The Earth’s social, is unquestionably the result of human activities. It cultural, political and economic systems provide is highly likely the observed changes toward a the context in which this complex human– warmer climate over the last century are a environment system evolves, and in which consequence of this increase (Figure 2, and attempts by human societies to change the future Prentice et al. 2001). direction of the carbon cycle will be made. However, the role of human activities in the The international scientific community has carbon cycle is complex. Over the past two responded to this unprecedented carbon challenge centuries, human activities — industrial by developing a ten-year Global Carbon Cycle production, trade and transport, agriculture, Joint Project. The project’s framework provides an forestry and energy use — have grown to a integrated perspective across disciplines as well as magnitude sometimes equalling or even exceeding national boundaries. The approach is to accept that global-scale natural forces in their influence on the humans and their activities are an integral part of carbon cycle. Human societies are not just uni- the carbon cycle, and that the human–environment directional drivers of change: they are impacted by system is a single, highly linked and interactive changes in the carbon cycle and climate, and they system that drives the dynamics of the carbon respond to these impacts in ways that feed back to cycle (Figure 3). The goal is to understand the e 6.5 g ra 6.0 e v 5.5 5.0 4.5 1961- 1990 a 4.0 e 3.5 m th o 3.0 ) fr C 2.5 o ( e 2.0 1.5 Bars show the ratur range in 2001 e produced by 1.0 several models mp e 0.5 in t in s 0 e -0.5 partur e -1.0 D 1000 1200 1400 1600 1800 2000 Year Figure 2. Variations of the Earth’s surface temperature (1000 to 2100 AD). Data from IPCC Third Assessment Report (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 Emissions Scenarios projections. 4 Atmospheric and Ocean Atmospheric Circulations Carbon Figure 3. The global carbon cycle from Solubility three perspectives over time. (a) During Pump glacial–interglacial periods and before significant human activities, the global Biological carbon cycle was a linked system Pump Disturbance Ecosystem encompassing stocks in the land, oceans Physiology and atmosphere only. The system was Land Ocean/ (and still is) controlled or driven through Carbon coastal Carbon climate variability as well as its own internal dynamics. For instance, the ocean carbon system was tightly coupled a to air–sea gas exchange as well as physical and biological “pumps” that transport carbon. Interactions of the land surface and atmosphere were driven by land and ecosystem physiology as well Atmospheric as disturbance. (b) Starting about 200 Fossil and Carbon Ocean years ago, industrialization and Atmospheric Circulations accelerating land-use change Carbon complicated the global carbon cycle by Solubility Industry Pump adding a new stock — fossil carbon. Transport Systems However, humans did not initially perceive that their welfare might be Biological Pump endangered. Regardless of how society responds to increased fossil fuel inputs Ecosystem Land-use Disturbance Systems Physiology to the atmosphere, or the consequences Ocean-use Systems of intensification of current land-use Land Ocean/ practices, the global carbon cycle has Carbon coastal Carbon been seriously impacted. (c) Over recent decades, humans have begun to realize that changes in climate variability and the Earth System may significantly affect b their welfare as well as the functionality of the global carbon cycle. The development and implementation of institutions and regimes to manage the global carbon cycle coherently provides Atmospheric a new set of feedbacks in the Fossil and contemporary era. Carbon Ocean Perceptions Atmospheric Circulations of Human Welfare Carbon Solubility Industry Pump Tr an sport Systems Changes in Biological Instutions & Pump Technologies Land-use Disturbance Ecosystem Systems Physiology Ocean-use Carbon stocks Systems Land Ocean/ coastal Processes Carbon Carbon Control points on carbon fluxes Process links Carbon flows c 5 underlying mechanisms and feedbacks that control themes that require cooperation and collaboration the carbon cycle, explain the current patterns of from international and interdisciplinary sources and sinks, and develop plausible communities: trajectories of the behaviour of the carbon cycle into the future. The project’s target is to provide 1. Patterns and Variability societies with significantly enhanced scientific knowledge of the global carbon cycle on which to 2. Processes, Controls and Interactions base policy debate and action. 3. Carbon Futures The Global Carbon Cycle Joint Project is co- sponsored by the International Geosphere– A fundamental question and a set of supporting Biosphere Programme (IGBP), the International questions guide the work under each theme. Human Dimensions Programme on Global Together, the themes provide the framework to Environmental Change (IHDP) and the World tackle the critical issues in global carbon-cycle Climate Research Programme (WCRP). It is research. organized around three fundamental scientific Atmosphere Ocean Land Disturbance 6 THE SCIENCE THEMES 1. Patterns and Variability: Understanding the spatial patterns of carbon fluxes What are the geographical and temporal on land and ocean and in the atmosphere is patterns of carbon sources and sinks? essential to inform the policy process. However, our current knowledge of spatial patterns