1. REMSAD Simulation of the BRAVO Tracer ExperimentMichael G. BarnaCooperative Institute for Research in the AtmosphereColorado State UniversityFort Collins, CO10 October 2002

2. The Modeling Process…. Primer on BRAVO Modeling:

3. Tracer Release Rates – Phase 1 (July 5 – September 16):

4. Tracer Release Rates – Phase 2 (Sept. 17 – October 30):

5. Tracer Release Sites and 6 hr Receptors:

6. PDCH tracer from Eagle Pass PDCH tracer from Eagle Pass BBNP BBNP Dispersion is a Lagrangian Process:

7. And a Three-Dimensional One:

8. Contour Maps of the Four Tracers:

9. Eagle Pass 12 Hour Timing Tracer at Marathon (PTCH):

10. Eagle Pass 24 Hour Timing Tracer at Monahans (PDCB):

11. Eagle Pass 24 Hour Timing Tracer at Big Bend (PDCB):

12. Eagle Pass Continuous Tracer at Persimmon Gap (PDCH):

13. Eagle Pass Continuous Tracer at Big Bend (PDCH):

14. San Antonio Tracer at Fort Stockton (PDCB):

15. Predicted and Observed Average Tracer Concentrations:

16. Correlation Coefficient:

17. Observed and Predicted PDCH – All monitors: y = 0.203 x + 0.361 R = 0.25

18. Conclusions: • Some skill in replicating timing (but often not magnitude) of the 12 hr and 24 hr Eagle Pass timing tracers • Measured and predicted tracer concentration from Big Brown (PPCH) low (< 1 ppqV) • Model tends to over-predict average concentrations at southern monitors • Correlation coefficients: 0.05 – 0.65