<Monsoon System Study Working Group>

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 se

asonal cycle

Plan for Monsoon System Study in GAME-IIBy 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 onsetFindings:• 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 Heat and moisture balance around the Tibetan Plateau using GAME-ReanalysisTibetan Plateau using GAME-Reanalysis η-cη-c

oordinateoordinate（（ σ-p hybrid coordinateσ-p hybrid coordinate ） ） datadata

((H. Ueda, H. Kamahori, N. Yamazaki, H. Ueda, H. Kamahori, N. Yamazaki, 2003, Journal of Climate, 16, 2309-23242003, Journal of Climate, 16, 2309-2324))● Method

Tt

VT RdCpP

k

dpdt Ý T

Q

1Cp

qt

Vq Ý q

Q2

Lcdpdt

Vk pk1/ 2 l (Vllk

k max

pl) (Vk )pk

2 , (3)

( Ý p

)k 1 2

pk 1 2

t (Vl

lk

k max

pl ), (5)

( Ý T

)

1

2pk

( Ý p

)k 1 2 (Tk 1 Tk ) ( Ý p

)k 1 2 (Tk Tk1 )

(6)

Ueda et al. (2003), Journal of Climate, 16 2309-2324

(2/5)

E-W cross section

PositiveQ2

Positive Q1

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 theAustralian 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:202D grid-plume model (vertical one layer)

Fully mix in a timestep (10 min.)Variables (Q, W, P, E) are

externally given.

EP

QUin QUout

QVout

QVin

W1.25˚x1.25˚

Method for Colored Moisture Analyses

Indian Ocean

Pacific Ocean

IndochinaPen.

BengalGulf

Contents of water on todayare 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 Onset and withdrawal of Asian summer monsoon using MRI-OAGCMmonsoon using MRI-OAGCM

By By Akio Kito & K. Rajendran (Akio Kito & K. Rajendran (Climatological Lab., MRI) Climatological Lab., MRI) Rajendran and Kitoh (2003) J.Climate (Submitted)Rajendran and Kitoh (2003) J.Climate (Submitted)

MRI CGCM2•AGCMAGCM

–MRI/JMA98MRI/JMA98–T42 (2.8x2.8), L30 (top at 0.4 hPa)T42 (2.8x2.8), L30 (top at 0.4 hPa)–Longwave radiation - Shibata and Aoki (1989)Longwave radiation - Shibata and Aoki (1989)–Shortwave radiation - Shibata and Uchiyama (1992)Shortwave radiation - Shibata and Uchiyama (1992)–Cumulus - Prognostic Arakawa-Schubert typeCumulus - Prognostic Arakawa-Schubert type–PBL - Mellor and Yamada level 2 (1974)PBL - Mellor and Yamada level 2 (1974)–Land Surface - L3SiB or MRI/JMA_SiBLand Surface - L3SiB or MRI/JMA_SiB

•OGCMOGCM–Resolution : 2.5x(0.5-2.0), 23layersResolution : 2.5x(0.5-2.0), 23layers–Eddy mixing : Isopycnal mixing, GMEddy mixing : Isopycnal mixing, GM–Sea ice : Mellor and Kantha (1989)Sea ice : Mellor and Kantha (1989)

•CouplingCoupling–Time interval : 24hoursTime interval : 24hours–With/without flux adjustmentWith/without flux adjustment

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

Seasonal Variation of climatological pentad mean precipitationSeasonal Variation of climatological pentad mean precipitation

70E-90E70E-90E

110E-120E110E-120E

120E-140E120E-140E

　

07/11/2003

Simulation of 1998 Monsoon Onset over Southeast Asia with a Regional Climate Model

Koji Dairaku 　

　 Atmospheric Environment DivisionNational Institute for Environmental Studies 　　

E-mail: dairaku.koji@nies.go.jp 　　　

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

0

3

6

9

12

15

4/ 1 4/ 11 4/ 21 5/ 1 5/ 11 5/ 21

mm

/day

Obs(GPCP)Obs(CMAP)CTLNOMNT

Simulation of 1998 Monsoon Onset with RAMS

Averaged to the 10 by 15 degree area (lat 10-20, lon 95-100)

Seasonal changes of lightning activity observed by TRMM-LIS

by Yasumasa Kodama, Akihiro Ohta et al., 2003

Pre-monsoon rains in Pre-monsoon rains in ThailandThailand

*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