US Program Overview

1. US Program Overview Scott Denning, Chair NACP Science Steering Group

2. NACP Questions • What is the carbon balance of North America and adjacent oceans? What are the geographic patterns of fluxes of CO2, CH4, and CO? How is the balance changing over time? (“Diagnosis”) • What processes control the sources and sinks of CO2, CH4, and CO, and how do the controls change with time? (“Attribution/Processes”) • Are there potential surprises (could sources increase or sinks disappear)? (“Prediction”) • How can we enhance and manage long-lived carbon sinks ("sequestration"), and provide resources to support decision makers?(“Decision support”)

3. atmosphere ocean forests farms cities industry ocean foresters farmers citizens industrialists economics institutions policy Sources, Sinks, and Processes • Carbon exchanges with the atmosphere over North America are managed by people • Decision Support Task Force to engage stockholders and help coordinate research & reporting

4. Program Elements: Question 1Diagnosis of Current Carbon Budgets • A hierarchical approach for large-scale, distributed terrestrial measurements • Substantially improved fossil fuel emissions inventories with high resolution downscaling in time and space, and methods for evaluating these inventories using atmospheric measurements • Hydrologic transfers of carbon over land, and sequestration in sediments • Ocean measurements and modeling, both in the coastal zone and the open ocean, in coordination with the OCCC • An atmospheric observing system consisting of ground stations, aircraft and measurements from towers • Spatially-distributed modeling of carbon cycle processes • Model-data fusion and data assimilation to produce optimal estimates of spatial and temporal variations that are consistent with observations and process understanding • Interdisciplinary intensive field campaigns designed to evaluate major components of the model-data fusion framework

5. %disturbed / yr 0 >2.0 Forest Disturbance Courtesy Jeff Masek, NASA GSFC LEDAPS Project PI: Jeff Masek (NASA GSFC) NACP Data Cubes PI: Samuel Goward (UMD) Landsat-based records of North American forest disturbance

6. North American Biomass Courtesy Jeff Masek, NASA GSFC J. Kellendorfer, WHOI

7. Five-Year Panel: Year One Year Two Year Three Year Four Year Five USDA Forest Service FIA Plots a gift to the NACP • 6000 acre grid cells • 1 plot per grid cell • >800K plots • each plot visited every 5 (east) or 10 (west) years Courtesy Dave Hollinger, USFS

8. Average annual live tree C stock change by county, estimated from FIA data MgC/ha/yr Courtesy of Linda Heath, USFS

9. Net cumulative change in soil carbon from 1991-2000 caused by changes in tillage intensity and crop rotations. Net change = 67.7 Tg C. Estimates of soil carbon change at 30x30m resolution using combination of remote sensing and inventory products Courtesy Tris West, ORNL

10. NACP and Coastal Oceans • Downstream reservoir for river DIC, DOC, and nutrients • Both upstream and downstream boundary for atmospheric trace gases Courtesy Scott Doney, WHOI • A zone of intense carbon and nutrient cycling in which biogeochemicalprocesses are not well observed or quantified

11. Air Parcel transport transport Sinks Air Parcel Air Parcel Sources Sample Sample Inverse Modeling concentration transport sources and sinks (model) (observe) (solve for)

12. N.A. Atmospheric CO2 Obs: 2004

13. Ring of Towers (summer 2004 only)

14. Expansion of Network? (2006)

15. NACP “Mid-Continent Intensive” (2007)

16. “Operational” Atmospheric Budgets Courtesy Wouter Peters, NOAA ESRL

17. Research Elements: Question 2Processes Controlling Carbon Budgets • Carbon consequences of terrestrial ecosystems to changes in atmospheric CO2, tropospheric ozone, nitrogen deposition, and climate • Responses of terrestrial ecosystems to changes in disturbance regimes, forest management, and land use • Responses of terrestrial ecosystems to agricultural and range management • The impacts of lateral flows of carbon in surface water from land to fresh water and to coastal ocean environments • Estuarine biogeochemical transformations; • Coastal marine ecology and sedimentation; • Air-sea exchange and marine carbon transport; and • Human institutions and economics • Urban & suburban land management

18. Warming Experiments in Oklahoma Long-term: 7-yearsWarming: 2oCClipping: Yearly One year, step changeWarming: 4oC Precipitation: doubled Courtesy Yiqi Luo, Univ of OK

19. Phenology Growing season Leaf Ps Respiration Plant growth Plant & soil C Microbial community Plant community NUE Quality of bulk litter Plant N uptake Litter Decomposition Available N Mechanisms underlying carbon-climate Feedback (after 6 years of ecosystem manipulation) • Warming extended growing seasons • Warming stimulated C4plant growth • Warming increased nutrient availability • All the above leads to increases in NPP • Warming stimulated respiration in a similar percentage to NPP • No net change in carbon balance or storage! Courtesy Yiqi Luo, Univ of OK

20. Project VULCAN Emissions Estimates(AREA Sources) natlog of tonnes C/day: January 3, 2002 Country-level consumption Distrib. By  Courtesy Kevin Gurney, Purdue Univ

21. Project VULCAN Emissions Estimates(POINT Sources) Tonnes C/day/facility Courtesy Kevin Gurney, Purdue Univ

22. Project VULCAN Emissions Estimates(ROAD Sources) Courtesy Kevin Gurney, Purdue Univ

23. Program Elements: Question 3Predictive Modeling • Transfer of synthesized information from process studies into prognostic carbon-cycle models • Retrospective analyses to evaluate the spatial and temporal dynamics of disturbance regimes simulated by prognostic models • Evaluation of predictions of interannual variations with predictive models against continued monitoring using observational networks and diagnostic model-data fusion systems • Development of scenarios of future changes in driving variables of prognostic models • Application and comparison of prognostic models to evaluate the sensitivity of carbon storage into the future • Incorporation of prognostic models into coupled models of the climate system

24. Fast time scale dynamics: Long time scale dynamics: Ecosystem Demography (ED) Model An “atmospheric” grid cell contains many patches Courtesy David Medvigy, Duke Univ

25. Program Elements: Question 4Decision Support • North American contribution to the State of the Carbon Cycle Report (SOCCR, King talk later today) • Analysis of the longevity of sinks • Assessment of sequestration options given best scientific evaluation of present and future behavior of carbon cycling • Provide scientific understanding to inform management of the carbon cycle given improved understanding, diagnosis, and prediction • Early detection of carbon cycle risks and vulnerabilities • Scenario development for simulation of future climate

26. North America is currently a net source of CO2 (1264 Mt C yr-1), with 30% of fossil fuel emissions (1856  464 Mt C yr-1 in 2003) offset by a net terrestrial sink of 592  296 Mt C yr-1. Courtesy Tony King, ORNL SOCCR CCSP SAP 2.2 State of the Carbon Cycle Report

27. observingnetworks predictivemodels maps of variablefluxes and stocks experiments model/datafusion decisionsupport diagnosticmodels NACP Integration Strategy • Process studies and manipulative experiments inform improved models • Systematic observations of land, ocean, and atmosphere used to evaluate models • Innovative model-data fusion techniques produce optimal estimates of time mean and spatial and temporal variations in fluxes and stocks • Improved models used to predict future variations, and tested against ongoing diagnostic analyses • Predictive models and continuing analyses used to enhance decision support

28. Conclusions • NACP consists of hundreds of individual research projects, supported by 9 US agencies • Ambitious objectives: diagnosis, attribution, prediction, and decision support for carbon cycle science over North America • Some easy connections and collaborations with colleagues in Canada and Mexico, some will no doubt have to find one another • Let’s get to work!