The operational forecast products from the National Center for Envirornmental Prediction (NCEP) (National Weather Services, Global Forecast System) are used to run MIMOSA in two PV “forecast” modes.
For the purpose of long-term forecasting (high resolution PV forecasts up to 168 h at intervals of 12 h), the global fields 1.25º x 1.25º from the NCEP GFS model are used. Short-term forecasts (up to 18 h with 3 h intervals) are also produced using additional forecast products from the NCEP GFS model. The pressure-gridded global fields (1000 hPa to 10 hPa) are interpolated onto 42 isentropic levels from 300 K to 750 K before being fed into the high resolution PV advection model.
In forecast mode MIMOSA is fed once a day using the NCEP forecasted wind and temperature fields to produce a series of global and regional high-resolution forecasted PV maps.
Figure 1 shows MIMOSA-advected PV maps over the Northeastern Pacific Region on March 16 at 0600 UT and 425 K (18 km), output from (top) the 72h forecast, (middle) the 18h forecast, and (bottom) the ECMWF T106 analysis. The consistency in the position and timing of the filament is remarkable between both forecasts, and between the forecasts and the analysis. The filament passed over the Big Island of Hawaii (the triangle-shaped southeastern most island of the archipelago) on two occasions: the first time on March 16, during the main vortex stretching event, when the filament tip slipped down from Alaska towards Hawaii (main motion was southward), and the second time on March 19 (not shown), when the “elbow” of the filament (i.e., its southwestern edge, located west of the islands) remained stationary for a few hours over the island, just before it initiated a high speed eastward motion towards Southern California.
The quality of the MIMOSA forecasts allows the JPL lidar group personnel to anticipate optimal ozone lidar measurements on nights of significant interest such as that shown here. Typically such filamentation events are mostly observed at Table Mountain (California, 34.4ºN), and are extremely rare at Mauna Loa (Hawaii, 19.5ºN).
Over the past 7 years the choice of the GFS model to feed MIMOSA was mainly driven by the need for, and easy access to, publicly available data on a near-real-time basis, which has been the case between 1999 and 2007 at the National Oceanic and Atmospheric Administration (NOAA) ftp site: https://ftp.cpc.ncep.noaa.gov.
Hauchecorne, A., S. Godin, M. Marchand, B. Heese, and C. Souprayen (2002), Quantification of the transport of chemical constituents from the polar vortex to midlatitudes in the lower stratosphere using the high-resolution advection model MIMOSA and effective diffusivity, J. Geophys. Res., 107 (D20), 8289, doi: 10.1029/2001JD000491.
Leblanc, T., I. S. McDermid, and A. Hauchecorne (2004), A study of ozone variability and its connection with meridional transport in the Northern Pacific lower stratosphere during summer 2002, J. Geophysical Research, 109, D11105, doi:10.1029/2003JD004027.
Tripathi, O. P., T. Leblanc, I. S. McDermid, F. Lefèvre, M. Marchand, and A. Hauchecorne (2006), Forecast, measurement, and modeling of an unprecedented polar ozone filament event over Mauna Loa Observatory, Hawaii, J. Geophys. Res., 111, D20308, doi:10.1029/2006JD007177.
Leblanc, T., O. P. Tripathi, I. S. McDermid, L. Froidevaux, N. J. Livesey, W. G. Read, and J. W. Waters (2006), Simultaneous lidar and EOS MLS measurements, and modeling, of a rare polar ozone filament event over Mauna Loa Observatory, Hawaii, Geophys. Res. Lett., 33, L16801, doi:10.1029/2006GL026257.