WACCM Meeting Notes 23 October 2006, NCAR Foothills Lab In attendance:

1. WACCM Meeting Notes 23 October 2006, NCAR Foothills Lab In attendance: Richmond (HAO), Marsh (ACD), Sassi (CGD), Tilmes (ASP/ACD), Kinnison (ACD), Liu (HAO), Wang (HAO), Fischer (CGD), Gettelman (ACD/CGD), Richter (CGD), Matthes (ACD), Hagen (HAO), Garcia (ACD)

2. Matthes: • WACCM Simulations with solar cycle and prescribed QBO… • Perpetual Solar Max, Min. Perpetual Solar Max, Min w/ QBO E&W for each. • Time varying solar: REF1 runs (CCMVal/WMO) 4x54 yrs. • Solar Proton Event • Time varying solar cycle and QBO: 1953-2062 2x2.5 (100 years 2x2.5) solar cycle only solar cycle and QBO Modeled Solar Signal in Ozone: Results from WACCM: similar vertical structure to data with QBO (E) SOLARIS Workshop: role of QBO in solar cycle important, role of observed SSTs? First intercomparison started.

8. Hagan: • Work with SOARS student (Hernandez) looking at Solar Min Perpetual QBO E&W • Looking at Tidal Variability in mesopause region: including QBO affects diurnal amplitude of tides in mesopause region.

13. Tilmes: • Polar Chemical Ozone Loss • Derive chemical ozone loss for antarctic from tracer-tracer correlations Antarctic looks okay, but arctic doesn't show much ozone loss. (Arctic vortex is too small and warm) • WACCM 4x5 v. 1.9x2.5 runs difference: PV gradients narrower in higher resolution run. (better related to observations, small ozone hole). Also changes temporal distribution of ozone loss. But Arctic O3 loss likelynot changed.

17. Kinnison • MOZART3 paper (with WACCM1b met fields): tropics is too isolated. Kinnison JGR 2006 has chemistry description. Also, age of air is young in tropics (too fast circulation or less mixing). Affects peak ozone distribution (too little NOy yields too much ozone at peak). • WACCM3 ozone recovery. • WACCM3 shows speeding up of brewer dobson circulation with climate change. • Future: Offline WACCM with GEOS-5 met fields. Up to 0.25deg resolution. Run at 0.5 degree resolution with 106 species mechanism. Offline WACCM: use met fields up to 50km, then let model take over May be very expensive.

21. Richter • New ASII Chris Fischer: developing a diagnostic package for WACCM right now focused on dynamics: U, T, GWdrag, SAO, MSAO. Add ERA data; Stratospheric warming diagnostic; Beres GW paramterization as a namelist variable • 2x2.5 v. 4x5: Momentum budget similar (EP flux divergence), winds similar. Lots of waves in upper atmosphere. Sensitive to time resolution ( 3hrly v. daily means). • Strat warming diagnostics: 4x5 is better than 2x2.5 ! (stronger vortex with higher resolution? not tuned properly?) variability is larger with QBO-E and with SST variability

25. Gettelman: • Supersaturation experiments (Gettelman, Kinnison). Paper to be submitted (this week) to ACPD Results: moderate effect, better tropopause annual cycle Small chemical effect, ~1W/m2 radiative forcing (3/4 clouds) No "water vapor feedback" in a coupled model. Polar Mesospheric Clouds (Merkel, Marsh, Gettelman) • Comparing WACCM PMC parameterization to CARMA (detailed -microphysical model) Develop as a standard piece of WACCM (separate physics module) • Upper Troposphere / Lower Stratosphere WACCM 91 level model with 300m vertical resolution in UT/LS Extratropical UT/LS: Pan (Use ref1 runs, also UTLS-WACCM) TTL (Gettelman, Birner, Fujiwara) • CCMVal activities. WMO Report & papers: 2 papers (Eyring et al 2006, 2007) CCMVal 2007: Leeds, UK. (discuss scenarios for next runs). Diagnostic Proposal to NASA: submission next week. • Garcia: • Tiedtke scheme being put into WACCM (by Giorgetta) • Liu: • Extending upper boundary from 140km to 500km. Meeting regarding how to do it. Do extension first and make it run. Then we will put in variable thermodynamic parameters. Mostly thermosphere part. Some further ionosphere development. • How to get CGD people involved? How to maintain and make it transparent: first maintain a separate package for upward extension of dynamical core. Then see if we can take the changes into the dynamical core.