Estimating regional sources and sinks of CO 2 for North America

1. Estimating regional sources and sinks of CO2 for North America Using NOAA-CMDL measurements and the TM5 model Wouter Peters, NOAA CMDL TRANSCOM May 13th, 2003

2. Acknowledgements Maarten Krol Pieter Tans Lori Bruhwiler Sander Houweling Peter Bergamaschi Peter van Velthoven Frank Dentener Jan Fokke Meirink John Miller

3. Outline • My background • The TM5 global & regional model • The expanded NOAA-CMDL network • Plans for inversions • Kalman filter • 4d-var

4. My background • Master’s in meteorology and physical oceanography from University of Utrecht • Thesis work on LBA-CLAIRE, airborne campaign in Suriname, South America. • PhD on tropospheric ozone in the tropics with Jos Lelieveld and Maarten Krol.

5. TM3 global model • 5x3.75 degrees, 19 layers • ECMWF meteorology (1979-1993, and 1994-1999) • Full chemistry (O3-NOx-CO-CH4, lumped NMHC’s) + coupled photolysis • Extensive budgets of all processes • Fast parallel version (<2 CPU hrs/yr) allowing multi-year simulations or sensitivity tests

6. TM5: the next generation • New advection algorithm (Berkvens, Botchev, Krol, Verwer, 2001) allows online nesting of fine-scaled grids within a global domain.

7. TM5 model – coarse grid

8. TM5 model – medium grid

9. TM5 model – fine grid

11. TM5 model – vertical resolution 25 vertical layers ~ 8 layers stratosphere ~ 12 layers free troposphere Hybrid coordinates values for US standard atmosphere ~ 5 layers PBL

12. TM5 • Contributions from IMAU, KNMI, JRC, and in the near future NOAA. • Most important improvements: meteorological input, coding, chemical boundary conditions. • Special emphasis: ERA40=> re-analysis of ECMWF for 1957-2001. • Resolution up to ECMWF operational

13. TM5 – latest developments- • Adjoint version of TM5 under con struction • 4d-var scheme from ECMWF implemented and working • Kalman filter (Baker, Bruhwiler, Tans) to be implemented

14. 222Rn simulations at different resolutions Courtesy: H. Sartorius IAR-Freiburg

15. My plans • Forward modeling of CO2 + isotopes, SF6 • Inverse modeling of CO2 + isotopes • Regional scale sources/sinks over the US • Using vertical profile/ tall tower data • Possibly assist in planning and optimizing network design/sampling strategies

16. NOAA CMDL goals ??????

17. Current network

18. 2005 network ?

19. 2010 network ??

20. Proposed TM5 grid

21. Proposed TM5 grid Denver Aspen Grand Junction Pueblo Durango

22. Regions for inversion

23. Fixed-lag Kalman smoother • ‘Batch’ inversion technique using n-months of information at a time (3 < n < 9) • Calculates new fluxes and error estimates for xJ=0 (where x= fluxes and J = cost function) • Balances prior flux estimates against new information from observations using prior flux and model-data mismatch • Computationally efficient for multi-decadal inversions • Details: David Baker’s talk tomorrow

24. 4d-var • Uses steepest descend and the calculated value of xJ to minimize J • value of xJ calculated by adjoint model • Iterative scheme to converge to xJ = 0 • Useful for short time periods and many observations

25. Gt/yr Gt/yr Seasonal CO2 Flux Estimates Land NCEP (1984-2000) ECMWF (1981-1993) PRIOR Ocean

26. Annual Average Flux Estimates Land NCEP (1984-2000) ECMWF (1981-1992) PRIOR Ocean

27. Annual Average Flux Estimates with Cyclic Meteorology Land NCEP (1984-2000) NCEP (1990) PRIOR Ocean

28. Interface: Mixture between ‘fine’ and ‘coarse’: = + Interface Zoom

29. XYZV VZYX xyzv vzyx vzyx xyzv Write BC Interface Zoom Update parent