NOGAPS-ALPHA model simulations of stratospheric ozone during the SOLVE2 campaign J. P. McCormack1, S. D. Eckermann1, L. Coy1, D. R. Allen2, Y.-J. Kim3, T. Hogan3, B. Lawrence4, A. Stephens4, E. V. Browell5, J. Burris6, T. McGee6, and C. R. Trepte5 1E.O. Hulburt Center for Space Research, Naval Research Laboratory, Washington DC, USA 2Remote Sensing Division, Naval Research Laboratory, Washington DC, USA 3Marine Meteorology Division, Naval Research Laboratory, Monterey, California, USA 4British Atmospheric Data Center, Rutherford Appleton Laboratory, Oxfordshire, UK 5NASA Langley Research Center, Hampton, Virginia, USA 6NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
Abstract. This paper presents three-dimensional prognostic O3 simulations
with parameterized gas-phase photochemistry from the new NOGAPS-ALPHA middle atmosphere
forecast model. We compare 5-day NOGAPS-ALPHA hindcasts of
stratospheric O3 with satellite and
DC-8 aircraft measurements for two cases during
the SOLVE II campaign: (1) the cold, isolated vortex during 11-16 January 2003;
and (2) the rapidly developing stratospheric warming of 17-22 January 2003.
In the first case we test three different photochemistry parameterizations.
NOGAPS-ALPHA O3 simulations using the NRL-CHEM2D parameterization give the
best agreement with SAGE III and POAM III profile measurements.
5-day NOGAPS-ALPHA hindcasts of polar O3 initialized with the NASA GEOS4 analyses produce better agreement
with observations than do the operational ECMWF O3 forecasts of case 1.
For case 2, both NOGAPS-ALPHA and ECMWF
114-h forecasts of the split vortex structure in lower stratospheric O3 on 21 January 2003 show comparable skill. Updated
ECMWF O3 forecasts of this event at hour 42 display marked
improvement from the 114-h forecast; corresponding updated 42-hour
NOGAPS-ALPHA prognostic O3 fields initialized with the
GEOS4 analyses do not improve significantly. When NOGAPS-ALPHA
prognostic O3 is initialized with the higher resolution ECMWF O3 analyses, the NOGAPS-ALPHA 42-hour lower stratospheric O3 fields
closely match the operational 42-hour ECMWF O3 forecast of the 21 January event.
We find that stratospheric O3 forecasts
at high latitudes in winter can depend on both model initial
conditions and the treatment of photochemistry over periods of 1-5 days.
Overall, these results show that the new O3 initialization,
and spectral transport in the NOGAPS-ALPHA
NWP model can provide reliable short-range stratospheric O3 forecasts
during Arctic winter.
Citation: McCormack, J. P., Eckermann, S. D., Coy, L., Allen, D. R., Kim, Y.-J., Hogan, T., Lawrence, B., Stephens, A., Browell, E. V., Burris, J., McGee, T., and Trepte, C. R.: NOGAPS-ALPHA model simulations of stratospheric ozone during the SOLVE2 campaign, Atmos. Chem. Phys., 4, 2401-2423, doi:10.5194/acp-4-2401-2004, 2004.