___________________________________________________________________________

2008/SOM3/ISTWG/SYM/023 Agenda Item: 3-06

The Goddard Earth Observing System 5 (GEOS-5) Model and Its Application to the Climate Research

Submitted by: United States

APEC Climate SymposiumLima, Peru

19-21 August 2008

19 August, 2008 APEC Climate Symposium, 2008

Abstract 3-06

The Goddard Earth Observing System 5 (GEOS-5) model and its application to the climate research

Myong-In Lee*

Global Modeling and Assimilation Office NASA Goddard Space Flight Center

Abstract

The Goddard Earth Observing System, Version 5 (GEOS-5) is the latest version of the data

assimilation system. It has been developed for supporting NASA’s Earth science research in data

analysis, observing system modeling and design, climate and weather prediction, and basic research.

The new system adopted the Gridpoint Statistical Interpolation (GSI) Analysis scheme and a new set

of physics packages for the atmospheric general circulation model (GEOS-5 AGCM), which have

been tuned for both weather and climate applications. In the presentation, we will introduce the

system in more detail and its performance, based on early results from the Modern Era Reanalysis for

Research Applications (MERRA), which will be the NASA’s new retrospective-analysis project for the

satellite era from 1979 through the present. A couple of on-going research that use the GEOS-5 and

its data assimilation technique will be also presented in an effort to extend our understanding and

prediction capability in the sub-seasonal time scale. We will assess the impacts of air-sea coupling on

the tropical MJO prediction, and the tropical influence on the extra-tropical weather extremes, by

applying the “replay” technique to the incremental analysis update (IAU) method.

--------------------------------------------- *Mailing address: Code 610.1, NASA/GSFC, Greenbelt, MD 20771, USA Phone: 1-301-614-5314, Email: myong-in.lee@nasa.gov

THE GODDARD EARTH OBSERVING SYSTEM 5 (GEOS-5) MODEL AND ITS APPLICATION TO THE CLIMATE RESEARCH

Myong-In Lee, Siegfried Schubert, Yehui Chang, Michele Rienecker, Max Surez, Ron Gelaro, Michael Bosiolovich, Julio Bacmeister, and the GMAO

Global Modeling and Assimilation Office (GMAO)NASA Goddard Space Flight Center

APEC Climate Symposium 2008(Lima, Peru, 19-21 August 2008)

Overview

• MERRA (Modern Era Reanalysis for Research Applications)– The GEOS-5 DAS and observations– A few early results

• Research applications– Hybrid (empirical+dynamical) Forecasts– Coupled hindcasts

MERRA(Modern Era Reanalysis for Research Applications)

• Global atmospheric reanalysis• Synthesizes the current suite of research satellite

observations (1979-present)• Provides the science and applications communities

with of a broad range of weather and climate data with improved estimates of the hydrological cycle

• Will be available from an online data server, the Modeling and Assimilation Data and Information Services Center (MDISC, http://daac.gsfc.nasa.gov/MDISC/index.html)

AGCMFinite-volume dynamical core (S.J. Lin)Moist physics (J. Bacmeister, S. Moorthi and M. Suarez)Physics integrated under the Earth System Modeling Framework (ESMF)Generalized vertical coord to 0.01 hPaCatchment land surface model (R. Koster)Prescribed aerosols (P. Colarco)Interactive ozonePrescribed SST, sea-ice

AnalysisGrid Point Statistical Interpolation (GSI from NCEP)Direct assimilation of satellite radiance data using

JCSDA Community Radiative Transfer Model (CRTM)

Variational bias correction for radiances

AssimilationApply Incremental Analysis

Update (IAU) to reduce shock of data insertion (Bloom et al.)

IAU gradually forces the model integration throughout the 6 hour analysis period

GEOS-5 Atmospheric DAS for MERRA(Supported by NASA MAP Program)

∂qn

∂t⎛

⎝ ⎜

⎞

⎠ ⎟

total

= dynamics (adiabatic ) + physics (diabatic ) + Δq

Model predicted change Correction from DASTotal “observed change”

Analysis

Background (model forecast)Raw analysis (from GSI)

Assimilated analysis(Application of IAU)

03Z 06Z 09Z 12Z 18Z15Z 21Z 00Z 03Z

Initial States for CorrectorAnalysis Tendencies for CorrectorCorrector Segment (1- and 3-hrly products)

MERRA Production• 2-year spin up at 2-degree resolution• 1-year spin up at ½ degree • Product Streams begin: Jan 1 – 1979, 1989 and 1998

Years inStream

MERRA 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08Stream 1 10Stream 2 10Stream 3 9ROSB 21G5-AMIP 26EOS

Spinup years Reduced Observing System Baseline (ROSB)

• n, Apr, Jul,

• 2 degree (scout) runs – Coarse resolution MERRA preliminary look at data and spin-up of satellite bias estimates.

1010112230

Years inStream

MERRA 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08Stream 1 10Stream 2 10Stream 3 9ROSB 21G5-AMIP 26EOS

NovNOAA-18

EOS AquaOct

F08

F15

SSM/IJul Dec

F10Nov

DecF11

Dec

DecF13

MayF14

May

Dec Aug

Apr Jul

Apr Jun

Jul

GOES-08

GOES-10

GOES-12

TIROS-NDec Feb

Jul Apr OctNovNOAA-6

FebSep NOAA-7

May Jun Jul OctNOAA-8

Jan NovNOAA-9

NOAA-10Dec Sep

Nov Jan Sep Sep NOAA-11

JunSep NOAA-12

Satellite Radiance Data Streams

JanNOAA-14

SepNOAA-15NovNOAA-16

JulNOAA-17

Dec

TOVS

ATOVS

EOS Aqua

GOESSounders

MERRA FILE COLLECTIONS• MERRA products are organized into 24 collections in HDF

• Data are produced on three horizontal grids:• Native ----------- (1/2 by 2/3 w/ FV conventions)• Reduced ------- (1 1/4 by 1 1/4 Dateline-edge, Pole-edge)• Reduced FV -- (1 by 1¼ w/ FV conventions)

• In the vertical, 3-D data are at:• 72 model layers• 42 pressure levels

• Temporal resolution:• 3D products are 3-hourly• 2D products are hourly and at native resolution

• Total online collections ~150TB

• Distributed through a modeling data portal at the Goddard DAAC (including GDS, ftp )

MERRA Status (as of 8/08/08)

Global mean Precipitation

2004 Tropical Precipitation (mm/day)GEOS-5 MERRA (0.5°) GPCP

On-going Research

Dynamical Forecast (conventional )

Hybrid Forecast

Hybrid Forecast (Empirical+Dynamical)Statistical Forecast Model(Jiang et al., 2008, Mon. Wea. Rev.)

Collab w/ JPL (D. Waliser, X. Jiang)

(1) Combined EOF analysis

(2) Lag-regression with two leading PCs

(3) PC Projected onto EOFs

20-day forecast of OLR and 200mb u-wind

Assessing the impact of the tropics

• Develop an idealized approach by constraining the tropics (30S-30N) to a reference analysis• Assess the tropical influences on the extra-tropics

A. Replay-tropics B. AMIP

Assessing the Impact of the Tropics (Tropical IAU)

RMS Errors in daily U200mb

(m s-1)Correlation Coefficient

02FEB2004

09FEB2004

16FEB2004

Replay-global 02FEB2004

09FEB2004

16FEB2004

Replay-tropics

Total precipitable water (shading) and precipitation (contour)

Extratropical precipitation

Sensitivity to the tropical forcing

(35N-45N)

Observations (GPCP)

Pineapple ExpressStorm

Replay-tropicsReplay-global

Ensemble Experiments(based on 10 with different ICs)

Forcing 30S-30N

Forcing 25S-25N

Precipitation (35N-45N)

Observations (GPCP) Hybrid Forecast

Pineapple Express

Initialized at 21Z 01 Feb

MJO hindcasts - Initialized from Coupled and Uncoupled Scout Replays

• ModelsAGCM (GEOS5 at 2X2.5X72)

CGCM (GEOS5+MOM4)• Replay runs (Scout data)

AGCM replay run: 1979, 1996, 1997, 2002AGCM replay run (w/o Q): 2002CGCM replay run: 1979, 1996, 1997

• 35-day HindcastsAGCM (1368 cases): 1979, 1996, 1997, 2002

CGCM ( 668 cases): 1979, 1996, 1997ICs: daily 21z in 1979, 1996, 1997, 2002 from replay runs

GEOS-5 “Coupled” Ocean AssimilationUsing Atmospheric Replay

∂qn

∂t⎛

⎝ ⎜

⎞

⎠ ⎟

total

= dynamics (adiabatic ) + physics (diabatic ) + Δq

Model predicted change Replay Correction from Existing Analysis

Total “observed change”

09Z 12Z 15Z 18Z 00Z21Z 03Z 06Z 09Z

Analysis from MERRA, ECMWF JRA-25, etc

Atmospheric Replay BackgroundAny existing atmospheric analysis

Assimilated atmos analysisNew ocean analysis

Coupled model forecast

“Initialized”States for Coupled forecast

03Z 06Z

Next coupledanalysis cycle

Coupled analysis cycle

Next Steps beyond MERRADeveloping Components of Future Integrated Earth System Analysis, with consistent analyses across all components

Atmosphere Constituents Aerosols

Land Surface Ocean Biology Physical Ocean

Assimilation of AMSRAssimilation of AMSR--E soil moisture retrievalsE soil moisture retrievals

Assimilation of TOPEX/Jason Altimeter DataAssimilation of TOPEX/Jason Altimeter Data

Assimilation of AURA/MLS and OMI OzoneAssimilation of AURA/MLS and OMI OzoneJan 04 Precipitation in MERRA Jan 04 Precipitation in MERRA Aerosol Transport Aerosol Transport

• Thank you!!

24

Satellite Data TOVS (TIROS N, N-6, N-7, N-8 )

1978/10/30 Ğ 1985/01/01 NCAR

(A)TOVS (N-9; N-10 ; N-11; N-12 )

1985/01/01 - 1997/07/14 NOAA/NESDIS & NCAR

ATOVS (N-14; N-15; N-16; N-18; N-18)

1995/01/19 - present NOAA/NESDIS

EOS/Aqua 2002/10 - present NOAA/NESDIS SSM/I V6 (F08, F10, F11, F13, F14, F15)

1987/7 - present RSS

GOES sounder TB 2001/01 - present NOAA/NCEP SBUV2 ozone (Version 8 retrievals)

1978/10 - present NASA/GSFC/Code 613.3

DATA SOURCE/TYPE PERIOD DATA SUPPLIER Conventional Data Radiosondes 1970 - present NOAA/NCEP PIBAL winds 1970 - present NOAA/NCEP Wind profiles 1992/5/14 - present UCAR CDAS Conventional, ASDAR, and MDCRS aircraft reports 1970 - present NOAA/NCEP

Dropsondes 1970 - present NOAA/NCEP PAOB 1978 - present NCEP CDAS GMS, METEOSAT, cloud drift IR and visible winds

1977 Ğ present NOAA/NCEP

GOES cloud drift winds 1997 Ğ present NOAA/NCEP EOS/Terra/MODIS winds 2002/7/01 - present NOAA/NCEP EOS/Aqua/MODIS winds 2003/9/01 - present NOAA/NCEP Surface land observations 1970 - present NOAA/NCEP Surface ship and buoy observations

1977 - present NOAA/NCEP

SSM/I rain rate 1987/7 - present NASA/GSFC SSM/I V6 wind speed 1987/7 - present RSS TMI rain rate 1997/12 - present NASA/GSFC QuikSCAT surface winds 1999/7 - present JPL ERS-1 surface winds 1991/8/5 Ğ 1996/5/21 CERSAT ERS-2 surface winds 1996/3/19 Ğ 2001/1/17 CERSAT

A special thanks to Jack Woollen for help with the conventional data streams and Leo Haimberger for the radiosonde corrections!!!!

This builds upon previous collaborative efforts between NCEP and ECMWF to improve input observations

MajorSource of InputData

26

∂qn

∂t⎛

⎝ ⎜

⎞

⎠ ⎟

total

= dynamics (adiabatic ) + physics (diabatic ) + Δq

Model predicted change Correction from DASTotal “observed change”

Analysis

Background (model forecast)Raw analysis (from GSI)

Assimilated analysis(Application of IAU)

03Z 06Z 09Z 12Z 18Z15Z 21Z 00Z 03Z

Initial States for CorrectorAnalysis Tendencies for CorrectorCorrector Segment (1- and 3-hrly products)

∂qn

∂t⎛

⎝ ⎜

⎞

⎠ ⎟

total

= dynamics (adiabatic ) + physics (diabatic ) + Δq

Model predicted change Correction from Existing AnalysisTotal “observed change”

Background (model forecast)Any existing analysis

Assimilated analysis(Application of IAU)

03Z 06Z 09Z 12Z 18Z15Z 21Z 00Z 03Z

Initial States for CorrectorAnalysis Tendencies for CorrectorCorrector Segment (1- and 3-hrly products)

Analysis from MERRA, ECMWF, JRA-25, etc

GEOS-5 DAS

GEOS-5 REPLAY

27

GEOS-5Atmosphere

GEOS-62011→

GEOS-5AO system

• Coupled to LSM• ADAS + Adjoint tools• Replay for “coupling”• O3 assimilation• Coupled to GOCART• Coupled to GMI Combo

• Non-hydrostatic capable

• Physics for hi-res• Chem assim• ADAS: 4D-Var weak

constraint

Weather - Climate coupling

Chemistry-Climate coupling

Chem-weather prediction

ESMIESA

• Ocean• ODAS• LDAS

Short-term climate predictions

“Coupled” A-O analysesScience

IESA with the ocean

GEOS System Roadmap

Products - instr. teamsField campaigns, NWP

MERRAScience

Beginning of IESA

GEOS-5n(2008-10)

• AGCM w. hydrostatic cubed sphere

• ADAS: 4D-Var prototype• LSM with Dyn. Veg.• Carbon species assim.• Ocean biogeochem• Sea-ice

Climate changeMore Science

PIESA (weakly coupled, consistent analyses)