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Japanese Reanalysis Project (JRA-25)
M. Sugi CPD / JMA
Workshop on Ongoing Analysis of the Climate Systems
18-20 August 2003, Boulder
Japanese Reanalysis Project (JRA-25)
Five-year joint project of JMA and CRIEPI (FY 2001-2005) - Climate Prediction Division / JMA - Climate Research Department / MRI / JMA - Central Research Institute of Electric Power Industry (CRIEPI)
JMA provides a data assimilation system.CRIEPI provides computer resources.
http://www.jreap.org/indexe.html
• To produce a comprehensive analysis data set from the JMA data assimilation system for 1979-2004, - for advanced operational climate monitoring services of JMA,- for dynamical seasonal prediction, and- for various activities in climate system and global warming studies.
• The analysis cycle will be continued in JMA-CDAS (JCDAS) after JRA-25.
Objectives of JRA-25
Schematic Framework
Chairperson Dr. Tomio Asai (Prof. Emeritus, Univ. of Tokyo/ JSTC) Members Prof. Toshiki Iwasaki (Tohoku Univ.) Prof. Masahide Kimoto (CCSR, Univ. of Tokyo) Prof. Toshio Koike (Univ. of Tokyo) Prof. Hisashi Nakamura (Univ. of Tokyo) Prof. Kimio Hanawa (Tohoku Univ.) Prof. Tetsuzo Yasunari (Nagoya Univ.)
Dr. Masato Sugi (CPD/JMA) Dr. Hajime Nakamura (NPD/JMA) Dr. Takashi Aoki (CRD/MRI/JMA) Dr. Masafumi Mizutori (CRIEPI)
JRA-25 Reanalysis Advisory Committee (2003)
CPD / JMA Mr. Kazutoshi Onogi (GL) Mr. Hiroshi Koide Mr. Masami Sakamoto Mr. Shinya Kobayashi MRI / JMA Dr. Nobuo Yamazaki Dr. Hirotaka Kamahori Dr. Kiyotoshi TakahashiCRIEPI Mr. Jun’ichi Tsutsui Mr. Hiroaki Hatsushika Dr. Shinji Kadokura Mr. Koji Wada
JRA-25 Reanalysis Working Group
JRA-25 Reanalysis Evaluation Group
26 members have been already enrolled as core member. So far all the members are Japanese, researchers from overseas are welcomed. Experimental production will be available soon.
Members-Access to the basic dataset of experimental and final products of JRA-25 through the Internet, and use them to their research activities. -Members are expected to contribute the evaluate work.
Core members-Core-members can request other output products and related data. -These requests are considered with higher priority (in the limitation of the project schedule and observation data license) -Core-members have an obligation to report the results of evaluation to the working group.
2002 2003 2004 2005
Collection of observational data
Format conversion and preliminary QC
Porting of DA system to CRIEPI
Construction of experiment and execution system
Development of monitoring system
Production
SystemFixed
Stream 1 1990-2004
Stream 2 1979-1991
Data distribution and comprehensive evaluation
MonitoringExperimentsSSTLand processTOVS assimilationSSM/I assimilationSonde bias correctionetc.
Schedule of JRA-25 (Financial year)
• T106L40 version of GSM (top: 0.4 hPa)• Global 3D-Var assimilation system• Land surface analysis (by T. Tokuhiro of CPD/JMA)• COBE SST and sea-ice
(by M. Ishii, T. Matsumoto et al. of CPD/JMA)• 3D-ozone profile produced by CTM of JMA is
given (by AED/JMA and MRI/JMA)
Assimilation System
• JMA archive (1979 - present)• ERA-40 observation (provided by ECMWF)
– ECMWF and NCEP merged conventional archive used in ERA-40
• Retrieved wind data surrounding tropical cyclones (provided by Dr. M. Fiorino of PCMDI/LLNL)– To analyze tropical cyclones correctly.
– This kind of retrieval data have not been used in any other reanalyses.
Observational Data(1)
• TOVS(ATOVS) level1c (provided by ECMWF)• Reprocessed GMS AMV wind (1987 - present, provid
ed by MSC/JMA)• Reprocessed METEOSAT AMV wind (1982 - 1988,
provided by EUMETSAT : included in ERA-40 observation data)– Every reprocessed wind data have Quality Indicator (QI).
– Only high QI data are assimilated.
• SSM/I (provided by NCDC)– Retrieved precipitable water is assimilated in 3DVAR.
– Snow coverage data are assimilated in snow analysis.
Observational Data(2)
Impact of TC Wind Data
There is no problem if the wind retrieved data are put into rich observation area.
• Ishii et al. – Centennial SST analysis from 1900– The Kobe correction marine data are assimilated.– Good consistency with GISST, NCEP-SST– Low quality around seaice in part of polar area but bei
ng improved for JRA-25.
• GISST(UKMO) and/or NCEP-SST were used in other reanalyses except JRA-25.
COBE SSTNino area
Quality ofreprocessed GMS winds
1988.10-11LowerWind –UGlobal
Each observation is compared with first guess
Classified by QI (Quality Indicator)
Only high qualitydata will be used.
observationfirst guess
0 QI≦ < 40
85 QI 100≦ ≦70 QI≦ < 85
40 QI≦ < 70観測値
第一推定値
データ数
値
Corr.=0.45 Corr.=0.43
Corr.=0.48 Corr.=0.94
High Quality
Radiosonde bias correction
ERA-40 project report 2 (Onogi 2000)
Daytime
Night-timeDifference
Sample count
Based on Onogi’s method which was applied in ERA-40Correction is switched by every country or domain based on the statistics by Onogi (2000).
Validation of the Seasonal Cycle of Snow Coverage
North America
Eurasia(%)
(%)(experiment by Tokuhiro)
Comparison of reanalyses timeseries (1988.10-1989.9)
R1: unnaturally changed
R2: naturally changed
JRA: similar to ERA-15 in autumn, similar to R2 in spring
ERA-15:not melted
Reanalyses Comparison
• Global, NH, tropics, SH means
• Period : 1988.10 ~ 1989.9 (for 1 year)– JRA-25 experiment JH09 (no TOVS assimilated)– NCEP/NCAR Reanalysis I– NCEP/NCAR Reanalysis II– ERA-15– ERA-40
• Only half year (1989.1 ~ 6)• Provided privately to Onogi by Per Kallberg
Global tropics(20S-20N)
NH(20N-90N)
SH(90S-20S)
100 hPa Temperature
Due to TOVS ?
Future Plan of JRA (personal view)
• JRA-30 (1979-2009) with Satellite Data
- TL319, 4DVAR
- reference for climate monitoring, model validation and JRA-50
- analysis and experiment of extremes (typhoon, heavy rain, etc)
• JRA-50 (1958-2009) without Satellite Data
- TL159
- analysis of long time climate variation
- validation of the model and DA system with JRA-30
• Historical Climate Simulation (1870-2009) - AMIP or C20C type ensemble simulation
- validation of the model with JRA-30
International Cooperation (personal view)
Ensemble
Re-analysis
- to assess model dependency
- validation of individual model
- CDAS for climate monitoring & prediction
Common
Observation
Database
- accumulation of observation data
- more feasible
reanalysis
Re-analysis
Product
Database
- free and easy access
- fundamental database for climate study
JRA-25 offcial web site
http://www.jreap.org/indexe.html