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Outline. Overview of modelling activities in WP8, WP9 and WP10 for the first year Time line of operational work The regional/shelf modelling approach: general concept The data exchange protocols. SVP-Scientific Validation period. The main operational and pre-operational periods. 0. 18.
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Outline • Overview of modelling activities in WP8, WP9 and WP10 for the first year • Time line of operational work • The regional/shelf modelling approach: general concept • The data exchange protocols
SVP-Scientific Validation period The main operational and pre-operational periods 0 18 24 PRE-TOP TOP March 1, 2003 Sept 1, 2004 Feb 1, 2004
WP8+WP9+WP10 main points for first twelve months • WP8: • Continuation of MFSPP forecasting activities with SYS2: MOM 1/8x1/8x31 + Mark II SOFA implementation MFSTEP OGCM ( OPA 1/16x1/16x71 levels and large Atlantic box) interannual runs • Mark III SOFA implementation with MFSTEP OGCM- SYS3 • WP9: • Configuration of regional models: initial condition from SYS2 • Interface with ECMWF MFSPP atmo. forcing and LAM atmospheric forcing • Implementation of Variational Initialization on SYS3 • Configuration of shelf models and advanced implementations • WP10 • Configuration of LAMs for three Mediterranean areas • Data transfer protocols • Intercomparison/scientific validation experiments
The forecasting system: atmospheric forcing and lateral boundary conditions
Regional modeling approach for forecasting (Task 9100) • Regional models, except Adriatic, will run on ‘slave’ mode, i.e., re-initialized once a week • Once a week they should receive lateral boundary conditions as daily mean values from OGCM (to start, later we will see if 12 hr averages are possible) • Open ocean boundary conditions: same as developed in MFSPP • Surface air-sea interaction vertical boundary conditions: 3 solutions • 1)Use bulk formulas with surface atmospheric parameters from LAM: see later • 2)Use mixed heat flux boundary conditions: radiative balance from LAM and turbulent fluxes recomputed • 3)Use the momentum, heat and salt fluxes from OGCM forecast • Initial condition adjustment control for regional forecast: • VI method – dynamical correction • Some days spin-up (POC- two weeks, DFMR- three days) with LAM analysis/OGCM lateral forcing- kinematical adjustment • Regional forecasting network design • Web Bulletin to be disseminated on the basis of the OGCM template (CLU work) • ftp site for the rapid downloading of fields • SVP for LAM-RegionalOceanModel coupling: Jan 1-31 2003 • To be provide by middle of JUNE 2003: • Description of model set up (hor & vert resolution, domain, physics) • List of model experiments to be done • Model Interface Manual (similar to OGCM sample)
Shelf modeling approach (Task 9100) • Revise or implement new model shelf domains • For new shelf models, start experiments with perpetual year forcing (UAT server) • Shelf models will run on ‘slave’ mode, i.e., re-initialized once a week • Once a week they should receive lateral boundary conditions as daily mean values from regional models • Open ocean boundary conditions: same as developed in MFSPP or others • Surface air-sea interaction vertical boundary conditions: as for the regional models • Initial condition adjustment control for regional forecast: as in regional models • Shelf forecasting network design • Web (template released) dissemination on the basis of the OGCM template • SVP for coupling: Year 2002 ---- TO BE CONFIRMED ------------ • To be provided by middle of JUNE 2003: • Description of model set up (hor & vert resolution, domain, physics) • List of model experiments to be done
The model data exchange protocols • Model data should be exchanged via ftp from • 1) the central ftp site at INGV to the three regional sites (UAT, IMC, LEGOS) • 2) the three regional sites should deliver data to the shelf models • Timing of data release: • Wednesday evening for the OGCM i.c. and lateral forcing fields • Early Thursday for the LAM fields • Forecast days: • OGCM: start forecast at 12:00 of TUESDAY (first ECMWF forecast meteo fields received for 18:00) • Regional models: start forecast at 00:00 of Wednesday using LAM forecast fields from 00:00 of Wednesday and daily average of first forecast day • Possible change by September 2003: • OGCM start forecast at 00:00 of Wednesday (first forecast meteo fields received for 06:00 of Wednesday) • OGCM data available through ftp from Jan. 2000 till today: ask password to Luca Giacomelli (giaco@ambra.unibo.it)
“Air-sea interaction parameterizations in the OGCM and the regional models-SubTask 9120” Outline OGCM forcing in analysis and forecast mode Adriatic forcing in analysis and forecast mode Future perspectives
The OGCM atmospheric forcing problem: the heat flux • Surface meteorological analyses and forecast variables are taken EVERY SIX HOURS. They are: • 10 m winds (northward and eastward components) • 2 meters air temperature and dew point temperature • Mean sea level pressure • Cloud cover • Other variables should be added for sensitivity experiments: • Total precipitation • Short and long wavelength SOLAR radiation fluxes; • Long wavelength radiation upward (outgoing longwave radiation flux); • SST is taken from the model simulation at each model time step (900 sec.) • Bulk formulas are used to compute surface heat fluxes on the basis of past oceanographic experience in coupling
The OGCM atmospheric forcing problem: the heat flux • Mediterranean heat flux issue: long term heat budget is negative, i.e., -7 +/- 3 W/m2 average over the Med. Area • Other problems: large aerosol at the surface (cooling effects) and Sahara dust that change optical properties of the atmosphere • Solution adapted up to now: • (1) Tune the air-sea parameterizations to get the correct long term mean heat budget • (2) Heat flux corrections added to the heat flux term • The heat equation is:
The heat flux continuation…. • Heat flux boundary condition with heat penetration: • If no heat penetration is considered then: • If heat flux correction is used:
Bulk formula used in air-sea surface boundary conditions for OGCM or regional models • Net solar radiation flux (Reed, 1977): • Outgoing longwave radiation flux (Bignami, May formulas …) • Sensible heat flux (Kondo, Budiko, Smith formulas….)
Bulk formulas continuation….. • Latent heat flux (kondo, Budiko, Smith formulas….) • Castellari et al. (1998), Angelucci et al., (1998) showed that choosing Kondo with May and Reed the long term average of the Mediterranean was achieved • OGCM analysis run uses heat flux correction to observed weekly mean SST min addition to interactive bulk formulas • In MFSPP, regional models with perpetual year forcing used climatology for Q and added heat flux correction, with different coefficients region by region • Also, it was found that the heat flux correction was decreasing with the nesting, if Q fields from the OGCM model were used in the nested models
The OGCM atmospheric forcing problem: the momentum flux • Wind forcing is translated into surface wind stress: • Using the Hellerman and Rosenstein formula for drag coefficient that becomes To-Ta, U dependent
The OGCM atmospheric forcing problem: the water flux • Evaporation, precipitation and runoff is used to compute the salt and water fluxes • MOM uses w=0, OPA is implicit free surface and uses complete water budget, POM normally does not have complete water flux formulation but the new version of POM has. R is added where needed; S is sea surface Salinity, S* is climatology
The Adriatic atmospheric forcing problem: the regional heat flux • Bulk formulas have been again assessed for the Adriatic area to get long term mean annual heat budget equal to -20+\- 5 W/m2 (Artegiani et al., 1997, Maggiore et al., 1998) • Reed, May and Kondo where found to be the ‘best parameterizations’ for ECMWF surface variables • Chiggiato et al. (2003) comparing ECMWF (0.5x 0.5 degrees) heat fluxes with LAM fluxes (1/8 x 1/8 degrees resolution) computed with bulk formulas, finds the ‘best parameterizations’