Kenneth Davis Department of Meteorology The Pennsylvania State University

1. NACP Diagnosis, attribution, prediction and decision support: Progress, problems and two paths forwards Kenneth Davis Department of Meteorology The Pennsylvania State University Co-chair, NACP Science Steering Group NACP 4th All Investigators’ Meeting Albuquerque, New Mexico 4-7 February, 2013

2. outline • Origins, goals and structure of the NACP • Progress, problems, changes • Paths forwards • Challenges, opportunities

3. Origins, goals and structure of the NACP

4. Relevant documents, groups, and programs • USGCRP – U.S. Global Change Research Program • NACP – North American Carbon Program • CCIWG - Carbon Cycle Interagency Working Group • U.S. Carbon Cycle Science Plan, Sarmiento and Wofsy, 1999 • CCSSG - Carbon Cycle Science Steering Group • NACP Plan, Harriss, Wofsy et al., 2002. • NACP SSG – NACP Science Steering Group • OCB - Ocean Carbon and Biogeochemistry Program • OCB SSG – OCB Science Steering Group • NACP Science Implementation Strategy, Denning et al., 2005 • CarboNA- collaboration with Mexican and Canadian research efforts • U.S. Carbon Cycle Science Plan, Michalak, Marland, Sabine, Jackson et al, 2011 http://www.nacarbon.orghttp://www.carboncyclescience.gov

5. US Carbon Cycle Science Plan Goals, 1999 • Quantify and understand the Northern Hemisphere terrestrial carbon sink. • Quantify and understand the uptake of anthropogenic CO2 in the ocean. • Determine the impacts of past and current land use on the carbon budget. • Provide greatly improved projections of future atmospheric concentrations of CO2. • Develop the scientific basis for societal decisions about management of CO2 and the carbon cycle. Origin of the NACP Origin of OCB CCSP 1999 led to the creation of the NACP and OCB. Additional goals didn’t create specific research programs.

6. Program structure(detail limited to the NACP)

7. Implementation Strategy, 2005 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”) • 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”) Current marching orders for the NACP.

8. NACP Approach diagnosis Observations Dynamic Maps Model-Data Fusion Decision Support Diagnostic Models attribution Experiments Predictive Models prediction Observations & Experiments  Science Results  Estimates-Uncertainties

9. Castle figure, with observations, experiments, process understanding at the base, prediction as the second floor, and decision support at the tower top. Some clouds in the way. Indicate terrestrial and marine systems. Note feedback.

10. What decisions are we supporting? • Climate and carbon management choices • Provide the scientific basis for decision makers to enact effective policy choices regarding managing future climate change and ecosystem changes associated with changing atmospheric CO2 and CH4. Focus on prediction. • Regulatory support • Provide the scientific basis needed to determine the effectiveness of measures taken to manage CO2 and CH4 sources and sinks. Provide methods that can quantify sources, sinks and stocks with the accuracy and precision required to support regulations. Focus on diagnosis.

11. NACP research community development to date • Community meetings • AmeriFlux meetings • All Investigators’ Meetings • 2007 Colorado Springs • 2009 San Diego • 2011 New Orleans • 2013 Albuquerque • (Also TRANSCOM meetings, ICDCs, AGU sessions…) • NACP Program office • Web site • List of investigations / investigators • Data management (ORNL DAAC, MAST-DC, CDIAC)

12. Major NACP research initiatives that have been completed • Midcontinent Intensive (MCI) regional study, 2005-2009 field work • Test of top-down and bottom-up diagnostic methods. Basis for evaluating the expansion of the N. American observational network. • Syntheses, 2008-2012 • NACP interim syntheses – regional and site, focus on data through 2006 • Coastal, non-CO2 GHG, disturbancesyntheses

13. Progress, problems, changes

14. Progress The MCI worked! Many (~30?) multi-year, continental C balance estimates have been brought together and evaluated. A follow-on continental C model comparison project (MSTMIP) is underway. Many N. American flux tower sites (30+) with multi-year records have been used to evaluate ~30 different terrestrial biosphere models. Extensive progress has been made in terrestrial disturbance studies.

15. (more) Progress Strong progress has been made synthesizing our knowledge of the coastal ocean carbon cycle. Carbon Tracker continues to function. Carbon Tracker methane exists. Strong progress has been made in carbon cycle data assimilation. Remote GHG column data is being acquired, and more is on the way!

16. (more) Progress • CO2 and CH4 sensor technology (in situ and remote) has advanced considerably. • Long-term flux tower data will be supported. • AmeriFlux will support a core “facility” of flux tower sites. • NEON will add more long-term flux tower sites. • NGEEs (next generation ecosystem experiments) are under development. Tundra and tropics.

17. (more) Progress Observational / experimental design studies are being used more actively. New research activities / intensives are focusing on vulnerable C stocks in high latitudes (NGEE, CARVE, ABOVE). New research / intensives are focusing on anthropogenic emissions (INFLUX, megacities). Years of NOAA aircraft and TCCON column data have been acquired over N. America.

18. (more) Progress A strong U.S. carbon cycle science research community has developed. A new carbon cycle science plan was written. The CCIWG has survived the reorganization of the USGCRP. Considerable research on terrestrial carbon management / decision support is underway.

19. Changes U.S. CO2 emissions are dropping. California and the EPA are regulating GHG emissions. Shale gas extraction has grown dramatically / gas leakage is a significant new issue. The age of satellite CO2 and CH4 measurement is upon us. A private-sector GHG measurement network exists. Considerable interest in methods to measure anthropogenic GHG emissions has emerged from the US government.

20. Problems NOAA’s tower network has not been expanded. We have not converged on estimates of the N. American carbon balance. Terrestrial biosphere models did not perform well vs. the N. American flux tower record. Carbon cycle prognostic skill is still poor. Transport uncertainty is still a major challenge for atmospheric inversions.

21. (more) Problems Knowledge of the coastal carbon cycle has many holes / uncertainties. Global remote sensing of biomass needs to be developed. Remote GHG column data faces questions regarding biases. Impact of the CCSP is unclear. Integration of natural and social sciences is still quite limited. NACP investigators struggle with data management.

22. NACP to date • The NACP is rich in diagnostic studies • Numerous individual studies • Sophisticated syntheses emerging • Convergence is elusive. We’re far from “done” • Progress has been made re: attribution, i.e. what are the factors governing the N. American carbon balance? • Significant uncertainty remains. • Predictive studies are less abundant. • Syntheses are limited to global studies. Predictive skill is poor. • Decision support research is sparse. Practical impact of the NACP is uncertain.

23. Two paths forwards

24. In the coming years our community should: • Expand our research agenda to include human systems (economics, energy systems, urban systems, land use, policy and behavioral studies) • Human systems govern the carbon cycle at least as much as marine and terrestrial processes. • This cuts across all NACP goals – diagnosis, attribution, prediction and decision support. • Advance our ability to predict the future carbon cycle. • This cuts across all NACP disciplines – coastal, terrestrial and human systems.

25. NACP Approach diagnosis Observations Dynamic Maps Model-Data Fusion Decision Support Diagnostic Models attribution Experiments Predictive Models prediction Observations & Experiments  Science Results  Estimates-Uncertainties

26. Logic for a new USCCSP, 2011 • “While many of the research goals in the 1999 Science Plan remain important for the coming decade, new research thrusts are also needed. These thrusts include: • a more comprehensive look at the effects of humans on carbon cycling, including the consequences of carbon management activities; • the direct impacts of CO2 on ecosystems and their vulnerability or resilience to changes in carbon and climate; • a quantitative understanding of the uncertainties associated with the carbon cycle; and • the need to coordinate researchers from the natural and social sciences to address societal concerns.”

27. New US Carbon Cycle Science Plan Questions, 2011 Question 1. How do natural processes and human actions affect the carbon cycle on land, in the atmosphere, and in the oceans? (first path) Question 2. How do policy and management decisions affect the levels of the primary carbon-containing gases, carbon dioxide and methane, in the atmosphere? Question 3. How are ecosystems, species, and natural resources impacted by increasing greenhouse gas concentrations, the associated changes in climate, and by carbon management decisions? (second path)

28. Challenge • Can we broaden our science and increase our focus on prediction with so many problems at the base of our structure? • One option – don’t broaden the science we address – that will stretch resources and endanger our base –diagnoses, and marine and terrestrial science. • A better option – broaden the research community. Bring in new resources. While also patching existing holes and converging on pending research problems. • A poor option – expand our science while letting our base of coastal and terrestrial science decay.

29. Examples: essential work to strengthen the base Pursue closure in the N. American carbon balance. Pursue expanded and secure coastal and terrestrial observational and experimental networks. Launch new research efforts to reduce transport uncertainty in atmospheric inversions. Improve terrestrial biosphere models’ ability to simulate the continental flux tower record. Build stronger data management resources.

30. Challenge • Can we make progress rapidly enough to serve decision support needs? Is our work relevant to carbon management needs? • Yes! Our results are already guiding decisions. • Emissions reductions needed for climate stabilization • Leakage rates that make CH4 problematic for GHG load • Current magnitude / rate of ocean acidification • Current terrestrial sink and plausible projections into the future

31. But there is clear value in doing better C4MIP: comparison of coupled climate/carbon models Land uptake uncertainty in 2100 of 16 GtC/year. Nearly 2x the current fossil fuel emissions rate. Friedlingstein et al., 2006

32. Observational constraints 10 Possible carbon cycle forecasts Future: Well maintained network Current Terrestrial uptake of carbon ( __C yr-1) 5 0 present -5 hindcast forecast Time Vision Experimental constraints (details of flux magnitude and observations left ambiguous - could be applied to many regions or observations) NACP interim syntheses?

33. What is “good enough?”: Idealized view (Where are we on this curve?) (What decisions are we supporting?) Regional flux uncertainty Threshold for data that are ‘good enough’ for our decision support needs. This is when we are done. (What is this number?) Investment in science to improve knowledge Decision support research sets the bar, science is conducted to reduce uncertainties, logical decisions follow.

34. What is “good enough?”: More realistic view (Where are we on this curve?) (What decisions are we supporting?) Regional flux uncertainty Threshold for data that are ‘good enough’ for our decision support needs. This is when we are done. (What is this number?) Investment in science to improve knowledge “Good enough” is the information available when the decisions must be made. We have little time to spare.

35. Charge to you • Correct my errors regarding the state of the science. • Consider how you can help to • solidify our base coastal and terrestrial science and/or • be a point of connection that helps to expand our science. • Consider how we can improve the feedback between fundamental science and decision support needs. • Continue building our research community.

36. The NACP is held together by: The continued, dedicated efforts of the CCIWG members. Look up who they are, and thank them. This is the most active, dedicated Interagency Working Group in all of the USGCRP. The work of the Carbon Cycle Science program office (GyamiShrestha), and the NACP office (Peter Griffith et al). Look up who they are, and thank them. The continued engagement of the Science Steering Groups, meeting program committees NACP investigators, etc. Your active participation makes this program go. Contribute. Volunteer. Take the initiative.

37. On-on!

38. New US CCSP Goals, 2011 Goal 1 (Q1, Q2): Provide clear and timely explanation of past and current variations observed in atmospheric CO2 and CH4 – and the uncertainties surrounding them. Goal 2 (Q1, Q2): Understand and quantify the socioeconomic drivers of carbon emissions, and develop transparent methods to monitor and verify those emissions. Goal 3 (Q1, Q2, Q3): Determine and evaluate the vulnerability of carbon stocks and flows to future climate change and human activities, emphasizing potential positive feedbacks to sources or sinks that make climate stabilization more critical or more difficult. Goal 4 (Q3): Predict how ecosystems, biodiversity, and natural resources will change under different CO2 and climate change scenarios. Goal 5 (Q1, Q2, Q3): Determine the likelihood of success and the potential for side effects of carbon management pathways that might be undertaken to achieve a low-carbon future. Goal 6 (Q1, Q2, Q3): Address decision maker needs for current and future carbon cycle information and provide data and projections that are relevant, credible, and legitimate for their decisions.