1 outline overview of modelling activities in wp8, wp9 and wp10 for the first year time line of...
Post on 19-Dec-2015
216 views
TRANSCRIPT
1
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
2
The main operational and pre-operational periods
March 1, 2003
PRE-TOP
Sept 1, 2004 Feb 1, 2004
0 18 24TOP
SVP-Scientific Validation period
3
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
4
SAT SUN MON WED THU J+5 J+10
IC=Initial Condition releaseLBC= Lateral Boundary Conditions release
TUE
LAM forcing FCST
ECMWF forcing FSCTNRT data collection
ECMWF analyses
INPUT
OUTPUT
MFSTEP_OGCM 10 days FCST release
REGIONAL 5 days FCST release
IC+
LB
C
NOWCAST/ ANALYSIS
MODEL
The forecasting system: atmospheric forcing and lateral boundary conditions
5
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)
6
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
7
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 ([email protected])
8
Deliverable Table for WP8
WP8 – D01 Year 2000 daily forecast and analyses fields archive;Continuation of MFSPP activities.
T0+2
WP8 – D02 MFSTEP OGCM T0+6
WP8 – D03 Initial conditions for Subtask 8130 T0+9
9
Deliverable Table for WP9
WP9 – D1 Protocols, Website Template 6 O
WP9 - D2 Bulletin Template 6 Re
WP9 - D3 Implementation of Regional Forecast Website and Bulletin
6 O
WP9 – D5 Report on regional/shelf model implementation 6 Re
WP9 – D6 Air-Sea coupling algorithms 6 O
WP9– D7 Distribution Protocols 12 O
WP9 – D8 Report on high frequency forcing effects 12 Re
10
Deliverable Table for WP10
WP10– D06 Definition of the inter-comparison protocol 6
WP10– D08 LAM surface data exchange protocols 6
WP10– D02 LAM1 model implemented in the Western Mediterranean and new AGCM2- post-processing procedure at 0.1 deg
9
WP10– D03 Merging procedures for central and western Med LAM1 – final LAM1 product at 7 km resolution for the region west of 22E
9
WP10– D04 LAM2 model implemented in the Eastern Med. area 9
WP10– D05 NRT LAM surface data for forecasting 9
WP10– D01 AGCM1 surface data for forecasting and development studies
12
WP10–D07 Corresponding LAM full volume atmospheric data archive for validation studies
12
“Air-sea interaction parameterizations in the OGCM and the regional models-
SubTask 9120”
Outline
1) OGCM forcing in analysis and forecast mode
2) Adriatic forcing in analysis and forecast mode
3) Future perspectives
12
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
13
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:
N
i
zis
ieTrQzI1
)(
z
I
Cz
TK
zTKTu
t
T
p
vh
0
1)()(
14
The heat flux continuation…. Heat flux boundary condition with heat penetration:
If no heat penetration is considered then:
If heat flux correction is used:
),,(),,,(),,,(1
0 wsawsasaBphz
v vTTHvrhTTLErhCTTQCz
TK
),,(),,,(),,,(),,(1
0 wsawsasaBsphz
v vTTHvrhTTLErhCTTQtCQCz
TK
15
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….)
)1)(0019.0C0621(QQ TOTs
2A4A
4SB C1762.01e00535.0653.0TTQ
4.3AS3Aa
4AB C75.01TTT4e005.04.0TQ
ASHPAH TTVCCQ
2
1 )sec(00)sec(
0
zaz
DIFFDIRTOT
QQAQQQQ
16
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
ASEEAE VCLQ
17
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
whz
v z
uA
0
18
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* isclimatology
19
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’
20
Year QTOT QS QB QE QH QAVE Data sets QB parameterisation
1998 -9 184 -78 -95 -20 -18 ECMWF 6-hourly surface
operational analysis and
1°x1° weekly Reynolds SST
MAY (1986)
ER1999 -15 183 -77 -99 -22
2000 -20 187 -80 -105 -22
2001 -30 183 -75 -113 -25
1998 -10 187 -70 -97 -31 -13 LAMBO 6-hourly surface
operational forecast and
1°x1° weekly Reynolds SST
MAY (1986)
LR1999 -6 184 -66 -94 -30
2000 -11 180 -64 -97 -29
2001 -26 172 -61 -103 -35
MAY (1986)
1998 10 184 -74 -85 -15 -2 ECMWF 6-hourly surface
operational analysis with ECMWF Skin
SST
ES1999 2 183 -74 -89 -18
2000 -4 187 -77 -96 -18
2001 -15 183 -73 -104 -21
1998 -2 184 -87 -85 -15 -15 ECMWF 6-hourly surface
operational analysis with ECMWF Skin
SST
BIGNAMI (1995)
EB1999 -10 183 -87 -89 -18
2000 -17 187 -89 -96 -18
2001 -30 183 -87 -104 -21
21
22