Agenda items: Status of REF1 and REF2 simulations Status of 2-deg model tuning

1. WACCM Meeting: 10/13/2005 Agenda items: Status of REF1 and REF2 simulations Status of 2-deg model tuning Running on ES and Columbia Possibilities for running at BCS WACCM documentation and WACCM website Discussion of available resources vs. research needs

2. 1. Status of restrospective and REF2 simulations

3. SSU + MSU 1979-1998 SAGE-I 1979-1981 and SAGE-II 1984-2000 Ozone and temperature trends (REF1) Comparison of simulated and observed zonal-mean T trends, 1979-1998 in the stratosphere Comparison of simulated and observed zonal-mean ozone trends, 1979-2000 in the stratosphere

4. O3 depletion and recovery in Antarctica, 1975-2045 (REF2) Chlorine loading, peaks in late 1990’s CLOy 86°S 1 mb Antarctic ozone column. Maximum depletion occurs in late 1990’s; recovery begins after ~2010-2015; 1980’s levels reached in 2040’s (series smoothed with a 12-month running mean) O3 column 86°S

5. 2. Status of 2-degree model tuning • Fabrizio, Byron have been tuning the model on Bluesky, Bluevista, Earth Simulator • Model still has at least two important biases/problems • SH cold pole bias; exacerbated by ozone hole interactive chemistry; breakup of SH vortex occurs too late; ozone depletion persists into January • NH winter: smaller number of sudden warmings than observed; breakdown of NH vortex is also too late

6. 3. Running on ES and Columbia Estimated machine comparison for 96 CPUs

7. Performance of a 5 day simulation on an Altix node on Columbia. All times are in seconds.

8. 4. Possibilities for running at BCS • Visited Barcelona Supercomputing Center (BCS) in september • Presented proposal to do retrospective and prognostic simulations with 2° model (essentially REF1 and REF2) • Proposal was well received; we have been offered the equivalent of 500 model years of computing resources at BCS • Stacy will need to ascertain that the model can be run efficiently at BCS (IBM pc970 (G5) system, 2 CPUs/node, 4 GB/node, Myrinet)

9. 5. WACCM documentation and website • Byron has written a draft WACCM3 document, which has been circulated to WACCM group • Need to fill in sections on chemistry, MLT physics • WACCM website needs to be updated with WACCM3 documentation and instructions for download • Model will be made available as is: no support for implementation • Timetable for completion?

10. 6. Computing resources vs. research needs • Resources • ES: ~ 300 model-years available at 2° • Columbia: ~ 300 model-years at 2° • BCS: ~ 500 model-years at 2° • CSL account: 9000 GAU (~15 model-years at 2°) /month • ESSL account: 3000-4000 GAU (~ 5-7 model-years at 2°)/month • available through end of 2006 • Note: need to write new CSL and ESSL proposals by end of 2005 • Research • Complete 2 additional realizations of REF2 at 4° • Solar cycle simulations (2 x 100 years + control; all at 2°) • Retrospective/prognostic (REF1/REF2) simulations at 2° • Other?

11. 1900 1910 1920 1930 1930 1940 1950 1960 1970 2030 1.9 x 2.5 degree runs, 1995 gases, climatological SST Bluevista Columbia ES Columbia QBO Solar Cycle + QBO Solar Cycle Smin, QBO W Smin, QBO E Smax, QBO W Smax, QBO E smax Control, 1995 smin