The comparison of The comparison of TransCom continuous TransCom continuous

experimental results at experimental results at upper troposphereupper troposphere

Takashi MAKI, Hidekazu MATSUEDA and TransTakashi MAKI, Hidekazu MATSUEDA and TransCom Continuous modelersCom Continuous modelers

MotivationMotivation1.1. To improve tracer transport model, To improve tracer transport model,

we need to know transport we need to know transport processes in detail.processes in detail.

2.2. Vertical transport process could Vertical transport process could affect tracer distributions (global, affect tracer distributions (global, regional).regional).

3.3. Aircraft observational data are Aircraft observational data are good indicator for vertical good indicator for vertical transport.transport.

4.4. We have tried to use aircraft We have tried to use aircraft observational data to check observational data to check vertical transport.vertical transport.

Comparison methodComparison methodExperimentExperiment : TransCom Continuous : TransCom Continuous

(Rachel, et al, 2005)(Rachel, et al, 2005)PeriodPeriod : 2002 – 2003: 2002 – 2003Observation: Tokyo - Sydney aircraftObservation: Tokyo - Sydney aircraft

(Matsueda, et al, 2002)(Matsueda, et al, 2002)Model output: hourly snap shot (at Model output: hourly snap shot (at

observational time)observational time)IndicatorsIndicators : Suitable : Suitable OffsetOffset

: : Standard deviationStandard deviation of of (model – observation) in (model – observation) in

the suitable offsetthe suitable offset

Observational DataObservational Data

Difference from Jan. 2003, equatorDifference from Jan. 2003, equator

Days from 1 Jan. 2002

TransCom resultsTransCom results

7 Jan 2003 values are subtracted from each result.7 Jan 2003 values are subtracted from each result.

Fossil 98 + Takahashi Ocean (2002) + SiB hourly conc.

TransCom results (2)TransCom results (2)

Add suitable (minimize standard deviation Add suitable (minimize standard deviation of (model – observation )) offset.of (model – observation )) offset.

FF98 + Takahashi 2002 +Sib hourly at 25N

368

370

372

374

376

378

380

382

10 100 164 221 282 349 419 483 533 596 659

AM2.GFDLAM2t.GFDLCCAM.CSIROCCSR_NIES1.FRCGCCCSR_NIES2.FRCGCCDTM.J MACOMET.ECNDEHM.NERIIFS.ECMWFLMDZ.LSCELMDZ_THERM.LSCENICAM.CCSR_FRCGCNIES05.NIES_ESCPCTM.CSUPCTM.GSFCREMO.MPIBGCSTAG.AISTSTAGN.AISTTM3_fg.BGCTM3_vfg.BGCTM5_eur1x1.SRONTM5_glb3x2.ESRLTM5_nam1x1.ESRLCDTM_rev.J MAOBSERVATION

TransCom results (3)TransCom results (3)

Add suitable (minimize standard deviation Add suitable (minimize standard deviation of (model – observation )) offset.of (model – observation )) offset.

FF98 + Takahashi 2002 + SiB hourly at 25S

368

370

372

374

376

378

10 100 164 221 282 349 419 483 533 596 659

AM2.GFDLAM2t.GFDLCCAM.CSIROCCSR_NIES1.FRCGCCCSR_NIES2.FRCGCCDTM.J MACOMET.ECNDEHM.NERIIFS.ECMWFLMDZ.LSCELMDZ_THERM.LSCENICAM.CCSR_FRCGCNIES05.NIES_ESCPCTM.CSUPCTM.GSFCREMO.MPIBGCSTAG.AISTSTAGN.AISTTM3_fg.BGCTM3_vfg.BGCTM5_eur1x1.SRONTM5_glb3x2.ESRLTM5_nam1x1.ESRLCDTM_rev.J MAOBSERVATION

SiB hourly Case

366.2

366.4

366.6

366.8

367.0

367.2

367.4

367.6

367.8

0.0 0.5 1.0 1.5 2.0

Standard deviation of (model - Obs.)

Offse

t (p

pm)

AM2.GFDLAM2t.GFDLCCAM.CSIROCCSR_NIES1.FRCGCCCSR_NIES2.FRCGCCDTM.J MACOMET.ECNDEHM.NERIIFS.ECMWFLMDZ.LSCELMDZ_THERM.LSCENICAM.CCSR_FRCGCNIES05.NIES_ESCPCTM.CSUPCTM.GSFCREMO.MPIBGCSTAG.AISTSTAGN.AISTTM3_fg.BGCTM3_vfg.BGCTM5_eur1x1.SRONTM5_glb3x2.ESRLTM5_nam1x1.ESRLO_CDTM_L.

TransCom Models ResultsTransCom Models Results

Do we need vertically less mixed model??Do we need vertically less mixed model??

less mixed

？

Fit to observations

Outlier??

Sensitivity Test Sensitivity Test 1.1. We prepare On-line (directly We prepare On-line (directly

coupled with GCM) transport model coupled with GCM) transport model with several vertical coordinates.with several vertical coordinates.

2.2. We adopt surface fluxes by We adopt surface fluxes by TransCom continuous experiment TransCom continuous experiment and compare CO2 concentrations.and compare CO2 concentrations.

3.3. We assimilate (nudging) re-We assimilate (nudging) re-analysis meteorological field to analysis meteorological field to drive On-line transport model. drive On-line transport model.

4.4. We also prepare a tuned off-line We also prepare a tuned off-line CDTM (less mixed in PBL and more CDTM (less mixed in PBL and more mixed in troposphere).mixed in troposphere).

Transport Model (GCM)Transport Model (GCM)Model NameModel Name : MJ-98 (Shibata et al.): MJ-98 (Shibata et al.)DynamicsDynamics : Global spectral model: Global spectral modelResolutionResolution : T42L45: T42L45Time stepTime step : 300s: 300sConvectionConvection : Arakawa-Schubert: Arakawa-SchubertRadiationRadiation : Shibata: ShibataLand surfaceLand surface : SiB: SiBDiffusionDiffusion : Mellor-Yamada (L2): Mellor-Yamada (L2)Gravity wave drag : IwasakiGravity wave drag : Iwasaki

Transport Model (CDTM)Transport Model (CDTM)NameName : CDTM (Sasaki et al.): CDTM (Sasaki et al.)

ResolutionResolution : : Same as GCM (T42L45)Same as GCM (T42L45)

(changed from 2.5 x 2.5 deg. L32)(changed from 2.5 x 2.5 deg. L32)

Time stepTime step : Same as GCM (300s): Same as GCM (300s)TransportTransport : : 3D Semi-Lagrange 3D Semi-Lagrange

(changed from 2D Semi-Lagrange)(changed from 2D Semi-Lagrange)

DiffusionDiffusion : Convection, Turbulent, : Convection, Turbulent, Shallow convectionShallow convection

Mass fixerMass fixer : Simple mass fixer: Simple mass fixer

TracersTracers : Same as Continuous exp.: Same as Continuous exp.

Current stage, we simply introduce Current stage, we simply introduce our CDTM vertical mixing into MJ-our CDTM vertical mixing into MJ-98.98.

Off-line VS On-line Off-line VS On-line

Main difference is vertical advection.Main difference is vertical advection.

Off-line On-line

Meteorology JRA-25 (6 hourly)JRA-25 (6 hourly,

nudging)

Vertical velocityAveraged diabatic

heatingFrom GCM (every

time step)Horizontal advection

2D Semi-Lagrange3D Semi-Lagrange

Vertical advectionUpwind Differencing

Scheme

Time step 300s 300s

Meteorological fieldMeteorological fieldWe adopt Japanese 25-year Reanalysis We adopt Japanese 25-year Reanalysis

Project (JRA-25) to assimilation.Project (JRA-25) to assimilation.

We could use precise and uniform We could use precise and uniform quality meteorological field (same quality meteorological field (same as Off-line CDTM).as Off-line CDTM).

Vertical CoordinateVertical CoordinateWe have tested 4 vertical coordinates.We have tested 4 vertical coordinates.

LL : Operational forecast model based: Operational forecast model basedHH : Stratospheric ozone model based: Stratospheric ozone model basedCC : CDTM based (attend TransCom): CDTM based (attend TransCom)C2C2 : CDTM based (divide lowest layer): CDTM based (divide lowest layer)

FF98 + Takahashi 2002 + SiB Monthly case

366.4

366.6

366.8

367.0

367.2

1.0 1.1 1.2 1.3

standard deviation of (model - obs.)

Offse

t

CDTM.J MAO_CDTM_L.O_CDTM_HO_CDTM_CO_CDTM_C2CDTM_rev.J MA

FF98 + Takahashi 2002 + SiB hourly case

366.2

366.6

367.0

367.4

367.8

368.2

0.9 1.0 1.1 1.2

Standard deviation of (model - obs.)O

ffse

t

CDTM.J MAO_CDTM_L.O_CDTM_HO_CDTM_CO_CDTM_C2CDTM_rev.J MA

FF98 + Takahashi 2002 + CASA monthly case

365.8

366.0

366.2

366.4

366.6

366.8

1.1 1.2

Standard deviation of (model - obs.)

Offse

t

CDTM.J MAO_CDTM_L.O_CDTM_HO_CDTM_CO_CDTM_C2CDTM_rev.J MA

FF98 + Takahashi 2002 + CASA hourly case

364.8

365.6

366.3

367.1

1.0 1.1 1.2 1.3

Standard deviation of (model - obs.)

Offse

t

CDTM.J MAO_CDTM_L.O_CDTM_HO_CDTM_CO_CDTM_C2CDTM_rev.J MA

Experimental Results Experimental Results

On-line models can reduce the offset.On-line models can reduce the offset.Vertical coordinates do not affect the offset.Vertical coordinates do not affect the offset.Vertical mixing tune is useful in hourly case. Vertical mixing tune is useful in hourly case.

less mixed

Fit to observations

Summary Summary We have compared our experimental results We have compared our experimental results

against aircraft data. The result shows against aircraft data. The result shows our models could almost reproduce our models could almost reproduce upper troposphere CO2 concentrations.upper troposphere CO2 concentrations.

We have prepared On-line transport model We have prepared On-line transport model nudging with re-analysis wind.nudging with re-analysis wind.

The On-line model could reduce the The On-line model could reduce the standard deviation (and the offset) this standard deviation (and the offset) this means that the model has good means that the model has good potential to tracer transport. potential to tracer transport.

For hourly biosphere flux, turning of vertical For hourly biosphere flux, turning of vertical mixing process could reproduce upper mixing process could reproduce upper observational data well.observational data well.

Future Plan Future Plan At this stage, we simply introduce our At this stage, we simply introduce our

transport model into GCM.transport model into GCM.In On-line model, we could use several In On-line model, we could use several

GCM parameters without spatial GCM parameters without spatial and temporal interpolation and temporal interpolation (cumulus convection, planetary (cumulus convection, planetary boundary layer diffusion, etc)boundary layer diffusion, etc)

We have a plan to attend Upper-air We have a plan to attend Upper-air and satellite inter-comparison and satellite inter-comparison project with these models to project with these models to understand vertical transport understand vertical transport process in detail.process in detail.

References References JRA-25 : http://jra.kishou.go.jp/index_en.htmlJRA-25 : http://jra.kishou.go.jp/index_en.htmlLaw, R., W. Peters, C. Rödenbeck 2005: PLaw, R., W. Peters, C. Rödenbeck 2005: Protocol for rotocol for

TransCom continuous data experiment.TransCom continuous data experiment. Matsueda, H., H. Y. Inoue, and M. Ishii 2002: Aircraft observation Matsueda, H., H. Y. Inoue, and M. Ishii 2002: Aircraft observation

of carbon dioxide at 8-13 km altitude over the western Pacific of carbon dioxide at 8-13 km altitude over the western Pacific from 1993 to 1999. Tellus, 54B, 1-21.from 1993 to 1999. Tellus, 54B, 1-21.

Sasaki. T, T. Maki, S. Oohashi and K. Akagi, 2003: Optimal sampliSasaki. T, T. Maki, S. Oohashi and K. Akagi, 2003: Optimal sampling network and availability of data acquired at inland sites. Gng network and availability of data acquired at inland sites. GLOBAL ATMOSPHERIC WATCH REPORT SERIES, No. 148, 77-LOBAL ATMOSPHERIC WATCH REPORT SERIES, No. 148, 77-79. 79.

Shibata, K., H. Yoshimura, M. Ohizumi, M. Hosaka and M. Sugi, 1Shibata, K., H. Yoshimura, M. Ohizumi, M. Hosaka and M. Sugi, 1999: A simulation of troposphere, stratosphere and mesosph999: A simulation of troposphere, stratosphere and mesosphere with MRI/JMA98 GCM. Papers in Meteorology and Geophere with MRI/JMA98 GCM. Papers in Meteorology and Geophysics., 50, 15-53. ysics., 50, 15-53.

Thank you for your Thank you for your attention! attention!