What progress has been made in the GAME Phase-I and what will be done in the GAME Phase-II? GISP-II meeting, Tokyo, November 6, 2002 By Jun Matsumoto, Univ. Tokyo National Working Group Members ： Jun Matsumoto* (Univ. Tokyo), Hiroaki Ueda* (Univ. Tsukuba), Ryuichi Kawamura (Toyama Univ.), Yasumasa Kodama (Hirosaki Univ.), Masato Shinoda (Tokyo Metrop. Univ.), Yukari Takayabu (Univ. Tokyo) International Working Group Member ： Johnny C. L. Chan* (Hong Kong City Univ.) * GISP member

What will be done in the GAME Phase-II? Full utilization of the GAME data-sets (re-analysis, satellite, upper and surface observations) Cross-cutting large-scale analysis over several intensive observation regions. Heating processes in the Asian monsoon seasonal transition: Role of land surface through heat and moisture budget analysis Quantitative estimation of Asian monsoon heat sources Interaction between mid- and low- latitude systems Relationship between Baiu/monsoon activity and convection over the Tibetan Plateau Relationship between Typhoon activity and SE Asian monsoon Quantitative estimation of precipitation system in the monsoon seasonal cycle

Plan for Monsoon System Study in GAME-II By Prof. Jun Matsumoto & Prof. Johnny C. L. Chan, GISP-II: Nov. 7, 2002 Main target: Pre-monsoon and monsoon onset processes How: Organize national (Japanese) workshop in February, 2003 Organize international workshop (In early November, 2003) with GISP meeting and GAME-T2 Workshop in Thailand co-organized with SCSMEX Project Office Include satellite and re-analysis related studies Organize regional studies/collaborations with Indochina countries Write a review paper on pre-monsoon and monsoon onset processes

Activity of GAME-II Monsoon System Study in 2003 By Prof. Jun Matsumoto GISP-II: Nov. 10, 2003 Organize national (Japanese) workshop: February 5- 6 (21 oral presentations) Make presentation in the “CEOP/GEWEX Workshop on the role of the Himalayas and the Tibetan Platesu within the Asian monsoon” : April 7-8, Milan, Italy Organize special session on “Understanding of onset mechanizm of tropical Asian monsoon” in the spring meeting of the Meteorological Society of Japan: May 24 (5 oral presentations) Organize international workshop (November 11) after the GISP meeting in conjunction with GAME-T2 Symposium in Thailand co-organized with SCSMEX Project Office (17 oral & 15 posters)

Summary of GAME-II National Monsoon System Workshop at Kyoto February 5-6, 2003 Main topic: Monsoon onset Findings: Monsoon onset is a transition from dry (shallow) monsoon to wet (deep) monsoon. Heating over the surrounding ocean in the pre-monsoon period is important for both Australian and Indian monsoon onset. Process of onset over Indochina and India may be different. Questions: What triggers the sudden onset? What is the role of the Tibetan Plateau? Is the inversion layer over Indochina contribute for the onset? What is the main factor causing difference of the monsoon onset in each continent? Is there any the relationship with the surrounding dry region? Key words for future study: Land-sea distribution, Role of vegetation, Moist process

(1/5) Heat and moisture balance around the Tibetan Plateau using GAME-Reanalysis η-coordinate （ σ-p hybrid coordinate ） data ( H. Ueda, H. Kamahori, N. Yamazaki, 2003, Journal of Climate, 16, ) ● Method

Ueda et al. (2003), Journal of Climate, (2/5) E-W cross section PositiveQ 2 Positive Q 1 Imply condensation process

Premonsoon circulation anomalies NCEP/NCAR Reanalysis Enhanced subsidence Ascending motion over the inland Development of thermal high Decreased mixing ratio 850hPa 700hPa (Kawamura et al., 2002; JGR)

A mechanism of the onset of the Australian summer monsoon ● Importance of air-sea feedback processes ● Dry intrusion into the layer at ~700 hPa level ● Inhibition of convection due to subsidence Kawamura et al. (2002; JGR) (Kawamura et al., 2002; JGR)

700-hPa mixing ratio and height Development of thermal high Low mixing ratio Increased mixing ratio associated with deep convection (Kawamura et al., 2003; JMSJ)

Tag spatial attribution onto evaporated water Sea:60 ， Land:20 2D grid-plume model (vertical one layer) Fully mix in a timestep (10 min.) Variables (Q, W, P, E) are externally given. EP Q Uin Q Uout Q Vout Q Vin W 1.25˚x1.25˚ Method for Colored Moisture Analyses Indian Ocean Pacific Ocean Indochina Pen. Bengal Gulf Contents of water on today are analyzed

Sudden increase of Indian Ocean May 17 Retrieval of Indian Ocean Sep. 28  Onset Withdrawal  Temporal variation on Bangkok

Onset and withdrawal of Asian summer monsoon using MRI-OAGCM By Akio Kito & K. Rajendran (Climatological Lab., MRI) Rajendran and Kitoh (2003) J.Climate (Submitted) MRI CGCM2 AGCM AGCM –MRI/JMA98 –T42 (2.8x2.8), L30 (top at 0.4 hPa) –Longwave radiation - Shibata and Aoki (1989) –Shortwave radiation - Shibata and Uchiyama (1992) –Cumulus - Prognostic Arakawa-Schubert type –PBL - Mellor and Yamada level 2 (1974) –Land Surface - L3SiB or MRI/JMA_SiB OGCM OGCM –Resolution : 2.5x( ), 23layers –Eddy mixing : Isopycnal mixing, GM –Sea ice : Mellor and Kantha (1989) Coupling Coupling –Time interval : 24hours –With/without flux adjustment

Onset Pentad: the Julian pentad in which the relative climatological pentad mean rainfall rate exceeds 4 mm/day.

Seasonal Variation of climatological pentad mean precipitation 70E-90E 110E-120E 120E-140E

07/11/2003 Simulation of 1998 Monsoon Onset over Southeast Asia with a Regional Climate Model Koji Dairaku Atmospheric Environment Division National Institute for Environmental Studies International Symposium on the Climate System of Asian Monsoon and its Iteraction with Society Sofitel Raja Orchid Hotel, Khon Kaen, Thailand, 11 – 13 November 2003

Ｈ 07/11/2003 Simulation of 1998 Monsoon Onset with RAMS Averaged to the 10 by 15 degree area (lat 10-20, lon )

Seasonal changes of lightning activity observed by TRMM-LIS by Yasumasa Kodama, Akihiro Ohta et al., 2003

Pre-monsoon rains in Thailand * Jun MATSUMOTO and Masashi KIGUCHI Dept. of Earth & Planetary Science, University of Tokyo, JAPAN

Climatological pentad rainfall Average onset Average onset Abrupt onset in India Gradual onset in Thailand

Rainfall Daily rainfall (March-May, 1998) Monsoon onset

Height anomaly at 300 hPa Zonal moisture flux at 925 hPa Moisture conv. at 925 hPa Precipitable water by GPS Precipitation Monsoon onset E W

Comparisons of seasonal changes of sensitive and latent heat flux over India (red) and Thailand (blue)

Plan for Monsoon System Study in GAME-II GISP-II: Nov. 10, 2003 By Prof. Jun Matsumoto Main target: Pre-monsoon and monsoon onset processes How: Organize national (Japanese) workshop February (?), 2004 Organize international workshop (In November, 2004, at Kyoto) with GISP and GAME Scientific meeting Organize regional studies/collaborations with Indochina countries Write a review paper on pre-monsoon and monsoon onset processes