1. How Important Are Temporal Constraints and Vertical Injection of Boreal Fire Emissions? Yang Chen 1,3, Qinbin Li 1,2, James Randerson 3, Evan Lyons 2 Ralph Kahn 1,4, David Nelson 5, David Diner 1 1 JPL 2 UCLA 3 UC Irvine 4 GSFC 5 Raytheon The 4 th GEOS-Chem Meeting, April 7, 2009, Harvard

2. Summer 2004 Alaska Fire Emissions: Temporal Constraints GFED v2 Diurnal: A mean diurnal cycle imposed on the 8-day emissions Synoptic: Synoptic variation imposed on the diurnal emissions Temporal constraints are added cumulatively Major fires Significant diurnal and synoptic variability.

3. Summer 2004 Alaska Fire Emissions: Vertical Injection Circles: MISR-derived smoke plume heights Vertical distributions of emissions 600+ plumes 10% reached free trop.

4. GEOS-Chem Simulations with Different GFED Configurations

5. Relative Importance of Individual Temporal Constraints Little effect from imposing a mean diurnal cycle.

6. Effects of Different Smoke Plume Heights on CO Uniform injection significantly decreases surface CO over source region while increases CO in the upper troposphere – Not a surprise.

7. Sensitivity of CO to Temporal and Vertical Constraints Surface CO over source region decreases while downwind CO increases

8. Effects on the Columns of CO and BC 1.Columns decrease over source region while increases downwind. 2.Most of that change is due to added temporal variations. 3.CO column change ~2%; BC: 10-20% kg/km 2

9. Effects on the Burdens of CO and BC CO and BC burdens from N.A. biomass burning Major fires

10. Effects on Downwind Vertical Distributions of CO and BC INTEX-NA 2004, all flights Black box: Median obs. 1.Uniform injection may overestimate upper tropospheric CO. 2.Not much difference among the temporal constraints and vertical injections. 3.Worse agreement in the lower troposphere.

11. Effects on the Vertical Distributions of CO and BC Individual flights during INTEX-NA 2004

12. Any Improvements to CO Column Simulation?

13. Effects on Surface BC: Comparison with IMPROVE µg/m 3 1.Going from monthly to 8-day makes largest difference. 2.Uniform injection makes things worse – underestimates surface BC. Temporal Vertical Temporal Vertical

14. Transport of Boreal Fire CO: The Role of Convection (a)300 hPa CO from N.A. biomass burning (b)B.B. Emissions (c)Vertical dist. of NA biomass burning CO and convective mass flux (d)Change in CO due to MISR-derived plume injection (e)Change in CO due to uniform plume injection White line: HYSPLIT trajectory Convection is possibly more important than plume injection height?

15. Backup slides

16. Emission-weighted Winds and Deep Convective Mass Fluxes Positive values: Eastward, northward, upward winds and fluxes Stronger vertical transport and horizontal advection with higher-temporal frequency emissions compared with the monthly mean emissions.

17. Any Improvement to CO Column? Temporal Comparison with MOPITT MOPITT CO with a priori fraction < 50% 1.Some improvement from temporal constraints. 2.Uniform injection makes things worse.

18. Any Improvement to CO Columns? Temporal Comparison with MOPITT MOPITT CO with a priori fraction < 30%

19. Any Improvements to CO Column Simulation?

21. Effects on AOD: Comparison with AERONET AOD If anything, going from monthly to 8-day makes largest difference.