Japanese Reanalysis Project (JRA-25) M. Sugi CPD / JMA Workshop on Ongoing Analysis of the Climate Systems August 2003, Boulder

Japanese Reanalysis Project (JRA-25) Five-year joint project of JMA and CRIEPI (FY ) - 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.

To produce a comprehensive analysis data set from the JMA data assimilation system for , - 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 Takahashi CRIEPI 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.

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 System Fixed Stream Stream Data distribution and comprehensive evaluation Monitoring Experiments SST Land process TOVS assimilation SSM/I assimilation Sonde bias correction etc. 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 ( 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 ( present, provided by MSC/JMA) Reprocessed METEOSAT AMV wind ( , 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 being improved for JRA-25. GISST (UKMO) and/or NCEP-SST were used in other reanalyses except JRA-25.

COBE SST Nino area

Quality of reprocessed GMS winds Lower Wind –U Global Each observation is compared with first guess Classified by QI (Quality Indicator) Only high quality data will be used. observation first guess 0 ≦ QI ＜ ≦ QI ≦ ≦ QI ＜ ≦ QI ＜ 70 第一推定値 値 Corr.=0.45Corr.=0.43 Corr.=0.48Corr.=0.94 High Quality

Radiosonde bias correction ERA-40 project report 2 (Onogi 2000) Daytime Night-time Difference Sample count Based on Onogi’s method which was applied in ERA-40 Correction 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 ( ) 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 : ～ (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 ( ～ 6) Provided privately to Onogi by Per Kallberg Globaltropics (20S-20N) NH (20N-90N) SH (90S-20S)

100 hPa Temperature Due to TOVS ?

Future Plan of JRA (personal view) JRA-30 ( ) 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 ( ) without Satellite Data - TL159 - analysis of long time climate variation - validation of the model and DA system with JRA-30 Historical Climate Simulation ( ) - 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