AMEGEWEX Asian Monsoon Experiment

GAME Letter
A Summary Report of the GAME-Tibet
Synthesis
1. Introduction

No.4

May 2002(JEXAM) under the framework of the Joint Coordination
Committee (JCC). Taking into account the importance of
seasonal variations in key processes, the experiments at
two different scales, the plateau-scale experiment and the

The GAME-Tibet project is an international land-atmo-

meso-scale experiment, were implemented. To understandsphere interaction field experiment implemented in the Ti-

one-dimensional land surface-atmosphere interaction pro-betan Plateau both at the plateau scale and a meso-scalecesses with spatial and seasonal variations, and to develop

under the framework of the World Climate Researchand validate sophisticated models, the plateau-scale ex-

Programme (WCRP) / Global Energy and Water Cycle Ex-

periment was carried out basically using the automatic

periment (GEWEX) Asian Monsoon Experiment (GAME).

weather station (AWS) and radiosonde networks. The

The overall goal of GAME-Tibet is to clarify the interac-meso-scale experiment was implemented in the central pla-

tions between the land surface and the atmosphere overteau, corresponding to the upper reaches of the Nujian

the Tibetan Plateau in the context of the Asian Monsoon

basin, by using two- and three-dimensional intensive ob-system. To achieve this goal, the scientific objectives ofserving systems. The characteristics of frozen ground vary

GAME-Tibet are to improve the quantitative understand-over a wide range, from continuous permafrost in the northing of land-atmosphere interactions over the Tibetan Pla-to seasonal permafrost in the south. The details of the ex-teau, to develop process models and methods for applying

periment design is provided in “GAME implementation

them over large spatial scales, and to develop and validatePlan” (GAME International Science Panel, 1998).

satellite-based retrieval methods. GAME-Tibet is an inter-

GAME-Tibet covered the north to south transect ob-

disciplinary, coordinated effort by filed scientists, model-

servation of the plateau-scale experiment and the wholeers and remote sensing scientists in meteorology and hy-

meso-scale one. The following measurements were done

drology to address these objectives.

during the IOP by the efforts of GAME-Tibet:

GAME-Tibet started in 1996 progressed rapidly through1) Land surface-atmosphere interaction

two experimental phases, the pre-phase observation pe-· Boundary Layer measurements by using the AWSs at theriod (POP) in 1997 and the intensive observation period

14 stations, the PBL tower at Amdo, and the turbulent(IOP) in 1998. It contributed to international research ac-

flux measurement at Amdo and BJ site.

tivities in the related science fields by providing the all· Intensive radiosonde observation at Amdo on selectedobtained data through the GAME-Tibet Data Information

days to investigate diurnal variations of the PBL in June,

System (DIS) in 2000. It has now moved on to the mostJuly and August.

rewarding part of project efforts for the analysis of results· Barometer network for local circulation measurement.

and the testing of new theories, models and algorithms.

2) Precipitation and cloud studies

This summary report is intended to introduce the reader· 3-D Doppler radar observation about 10 km south of

to GAME-Tibet briefly and to summarize some of the sig-

Naqu from the end of May to the middle of September.

nificant findings of the science teams of GAME-Tibet,· Ground-based precipitation measurement using the rainemphasize scientific gains in reference to the GAME-Tibet objectives, and outline some future research directions.
2. Experiment Design

gauge network in the mesoscale area.
· A snow particle measurement system and a microwave
radiometer for measurement of total water vapor andcloud liquid water content at Naqu.

The process-, modeling-, and satellite-based studies were

· A GPS receiver for water vapor measurement at Amdo.

carried out in cooperation with the Chinese national Ti-

3) Land surface monitoring by satellite remote sensing.

betan Plateau Experiment (TIPEX) and the China-Japan· Ground truth data collection of spectral reflectance, soil

Cooperative Study on Asian Monsoon Mechanisms

moisture, surface temperature and surface roughness

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along the north-south transect and in the west part of
the Tibet.

GAME Letter No. 4

4.1 Atmospheric Boundary Layer
The exchange of sensible and latent heat at the interface

4) Cold region hydrology including permafrost studyof atmosphere and the land surface was directly measured· Soil moisture and temperature measurements along theby eddy correlation method based on the measurement ofnorth-south and east-west transects.
· River discharge and evaporation measurements in themeso-scale area.

atmospheric turbulence. Four flux sites, Amdo, MS3478,
BJ (Naqu) and MS3637, were set up and the measurements
were conducted during the IOP. In these sites the radiation

5) Isotope study on precipitation and surface water

budget, soil surface temperature, soil temperature profile,· Isotope sampling for study on the origin of precipitationsoil moisture profile and soil heat flux were also measured.

and its recycling along the north-south and east-west

These measured results serve as a consistent database totransects.

study land surface-atmosphere interaction.

· Isotope sampling for understanding formation processes

With these results both diurnal and seasonal changes ofof stable isotopic composition in the meso-scale experi-

the sensible and latent heat flux were clearly detected atmental field.

Amdo where the longest and continuous data were ob-

67 scientists, including 37 Japanese, 25 Chinese and 3

tained. Before the monsoon, the ground surface was very

Korean, organized the 5 expedition teams for the 5 months

dry and the diurnal change of the surface temperature was

IOP from May to September in 1998. Each team coveredas large as 50 degrees Celsius. The latent heat flux was

one month observation by staying in Naqu or Amdo for 35

very small and the sensible heat flux was dominant. As theday including the 5 days overlapping with the next team.

ground surface became wet after the onset of monsoon,

The AWSs in the west Tibet were maintained by JEXAM.

the latent heat flux increased and the sensible heat flux
decreased. This change was in harmony with the decease

3. GAME-Tibet Data Information System (DIS)of the ground surface temperature. Typical diurnal change

According to the GAME-Tibet data policy, “final vali-of fluxes was also obtained for pre-monsoon, mid-mon-dated datasets obtained during the POP and IOP will besoon and late-monsoon periods (Ishikawa et al., 1999).

open to the international science community by June, 2000”,

Tsukamoto et al. (2001) compared the flux observation

a data information system that could serve not only theat four sites. They also showed that the sensible heat flux

GAME-Tibet investigators but also wider research com-controls the development of the depth of mixing layer.

munities was generated as a tool for archiving and distrib-

At these flux sites, Tanaka et al. (2001a, 2001c),

uting the complex datasets after the data collection efforts

Miyazaki et al. (2001), Wang (2001) and Kim et al. (2001)(Tamagawa et al., 2001).

reported ‘flux imbalance’. They suggest that many factors

The level 2 data (quality checked and uniformly reformat-

are responsible for the imbalance. They also stress theted physical data associated with the detail information on

importance of mean vertical motion of air mass whichsite location, sensors, and observers) were transferred frommay be induced by small scale organized disturbances.

the raw data obtained during the POP and IOP by the ob-

Tanaka et al. (2001c) gave a discussion on the measure-servers. All level 2 data were archived at the GAME-Tibet

ment of soil heat flux. They roughly estimated the sur-GIS and are opened through the user-friendly interface offace soil heat flux needed to melt the permafrost and to

WWW (http://monsoon.t.u-tokyo.ac.jp/tibet/index.html).

heat the soil layer from April to June using the soil mois-

Several pictures of the site and sensors and figures for theture and temperature data. The required surface heat flux

data quick view are also attached with the level 2 data at

was about 30 W/m2 on average, which was greater thaneach site and its documentation for users’ convenience.

that measured by soil heat plate. Tanaka et al. (2001b)

4. Summary of Results

examined the performance of a heat plate numerically andIn this section, the results of the four science groups

suggested that some correction is necessary to the soilthat were loosely arranged along disciplinary lines: atmo-

heat flux. The surface imbalance problem has not yet been

spheric boundary layer, hydrology, modeling and remoteresolved. This severely limits the usefulness of the ob-

sensing will be described.

served flux data.

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GAME Letter No. 4

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The western Tibet is a region where the distribution of

from the data obtained at Amdo (Numaguti et al., 1999).

meteorological station is very sparse. Two automated me-

One is an increasing trend of d-excess during continuous

teorological stations were set up at Gaize and Shichuanhe

precipitation periods. The value is about 10 at the begin-and the continuous measurements of surface boundaryning phase of each precipitation event and over 20 in later

layer and some soil variables have been conducted.

stage. The other is an overall large value of d-excess, about

Haginoya (2001) reported the surface meteorology and20, especially under a large-scale disturbance which em-

fluxes estimated by the Bowen ratio method at these sites.

barked water vapor from south rather than from west. To

Xu and Haginoya (2001) estimated the monthly averaged

explain this phenomena physically, a global isotope cir-surface fluxes at fourteen Tibetan sites using conventional

culation model, which does not include fractionation pro-surface observation data. At Amdo site PBL tower obser-

cess, was introduced. It suggests the importance of cloudvation has been continued after the IOP. Tanaka et al.

process for high d-excess value.

(2001d) compute the bulk transfer coefficient for the

Kuwagata et al. (2001) pointed out an important rolesensible heat flux at the site by comparing the tower dataof the mountain-valley circulation with the very typicalwith turbulent flux during IOP. The coefficient is obtained

diurnal variation in the water vapor transport in the Tibetan

as a function of the bulk Richardson number. With thisPlateau. Based on the radiosonde observation, the precipi-

coefficient and the continued tower observation data theytable water decreased in the daytime at the valley area,

computed the sensible heat flux until July 2000. The data

while that increased during daytime over the mountain range.

suggests the strong interannual variation, even the tower

The magnitude of the diurnal variation ranged from 2 to 6

observation failed in Spring, when the sensible heat flux

mm, which varied with time and space. The ECMWF 4DDAis largest in the year.

product also shows significant daytime decrease of pre-4.2 Hydrological Processes

cipitable water appeared in the valley regions around Naqu.

The seasonal march in the Tibetan Plateau is character-

Analysis of the GMS-5 water vapor channel image also

ized clearly by the rainy period and the dry one. During theindicated overall daytime increase of water vapor over the

rainy season, the active convection associated with a big

Plateau, but with some valley regions of daytime decrease.

amount of diabatic heat release plays an important role inThis diurnal variation of water vapor was also quantita-

the Asian summer Monsoon system. To understand andtively simulated by a two-dimensional numerical model.

model the seasonal and interannual variability of the Asian

4.2.2 Precipitation fields

summer Monsoon, it is important to address the hydro-

The intra-seasonal variation of the convective activity atlogical processes, especially the origin and circulation

the plateau-scale depends deeply on the variations of mid-of water vapor at large scale, the precipitation fields, andlatitude baroclinicity and the Tibetan anti-cyclone, while

the land surface hydrological processes in the permafrost

the spatial and diurnal variations of the convection are

in the Tibetan Plateau.

closely related with the mountain-valley topography in the

4.2.1 Water vapor transport and water cycle in and aroundplateau (Ueno, 1998; Kurosaki and Kimura, 2001). There

the plateau

are three types of meso-scale disturbances: the convec-

Two approaches, the stable isotope study and the ob-tive echo structure in daytime associated with vortex gen-servation and modeling of the local circulation were intro-

eration mechaaanisms, the stratified echo in nightime, andduced to understand the origin and transport of water

the combined system with frequent weak rainfall (Uyeda

vapor.The results of precipitation sample analysis for stable
isotope study show the similar temporal variation of ?? 18O

et al., 2001; Shimizu et al., 2001).
4.2.3 Land surface hydrological processes in the perma-in daily precipitation at the six sites in the meso-scale experiment field, the very low value of ? 18O in precipitation

frost
The hydrological variability of permafrost was investi-

under the strong monsoon, and the higher ? O value asso-gated both in the plateau- and meso- scales in the Tibetan

ciated with the convective precipitation (Tian et al., 1999).

Plateau. The plateau scale soil moisture distribution and its

The two characteristic feature of d-excess, which is often

seasonal and interannual variations were observed by theused for estimating the origin of the water, were foundspace-based passive microwave remote sensing data. The

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GAME Letter No. 4

thawing and freezing processes and their spatial andpressure head of subsurface water ranged from -10 to -interannual variations were studied in the plateau scale by

100 cmH2O and zero flux plane was often observed above

using the ground-based soil moisture and temperature pro-the depth of 30 cm. The groundwater recharge was very

files and atmospheric forcing data. The satellite synthetic

active during this period, thus the groundwater table rose

aperture radar (SAR) data is used for detecting the surface

up to the depth of 55 cm in the beginning of September.
The ?D and ? 18O of shallow subsurface water varied mark-soil moisture heterogeneity in the meso scale. A wide rangeof the meso-scale distribution of soil moisture in the permafrost region was examined by the observed data at several

edly with precipitation and evaporation, whereas those ofgroundwater were stable. The mean ? 18O of groundwater

The SSM/I surface soil moisture product shows the sea-

was 3.4 ‰ higher than the volume weighted mean ? 18O of
precipitation. The difference of ? 18O between the ground-sonal march of the soil moisture distribution in the Tibetanwater and the precipitation would be caused by isotopic

Plateau. The north-east and center parts of the plateau be-enrichment along with evaporation from the soil surface,

come wet in June while the other part is still dry. The wet

and 27 % of precipitation might be lost by evaporation

area expands to north and west in July and to south infrom the soil surface (Tsujimura et al., 2001).

August. The center part keeps wet during the summer. Re-

4.3 Modelingflat areas and on a slope (Koike et al., 2001b).

garding to the spatial and temporal variation of soil mois-

Field observations under a wide range of meteorologicalture and temperature profiles along the Qinghai-Xizang high-and hydrological conditions motivated the development

way, very clear spatial variability was identified, that is, theand testing of key process models describing soil moisturedryer and colder north and the wetter and warmer south,

and temperature profiles, flux exchange at the surface-at-

while any clear interannual variation between in 1997-1998

mosphere interface, boundary layer flux profiles, radiative

and 1998-1999 was not seen (Koike et al., 2001b). The

transfer, cloud formation and rainfall. In addition to one-seasonal march of the soil moisture and temperature pro-dimensional modeling of land-atmosphere interaction,

file variation at the experimental slope suggested that themeso-scale and regional–scale modeling, and methods forwide range of the soil moisture distribution along thescaling up land surface process were investigated.

slope, that is, wet valley and dry hilltop, was caused by the

4.3.1 One-dimensional modeling of land-atmospherepermafrost hydrological processes on the slope associ-interactions

ated with the surface and sub-surface water flow along

A new frozen soil parameterization in the land surface

the slope and the surface energy budget differences due

scheme was developed by incorporated a modified approxi-

to the soil moisture distribution (Ishidaira et al., 1999).

mation Stefan solution in the framework of the land surface

In addition, the wide range of soil moisture distribution

model - SiB2 to calculate the frost/thaw depth over time,and its significant seasonal variation were also observed

and to estimate the soil moisture and temperature profiles

even at the flat areas. The wetter area appeared in theduring the freeze-thaw cycle. The structure of the soil model

concaves, while the dryer in the convexes. Hirose et al.

in SiB2 is kept but the governing equations of water bal-

(2000) pointed out the importance of the interactive pro-ance and surface heat balance are modified to account for

cesses between the micro-topography and soil moisturesoil freezing/thawing. The model was calibrated and vali-

in the permafrost region. The detention in the concaves

dated using the GAME-Tibet observations (Li and Koike,keeps the active layer shallow due to the larger thermal2001). The new model estimates the frost depth more pre-capacity of soil and the larger amount of latent heat flux

cisely, predicts the soil temperature reasonably and phasein the wetter area while the active layer grows more rap-transition time more realistically than original SiB2.

idly in the convexes due to the larger amount of soil heatflux.

An one-dimensional heat and water flow model was developed to simulate soil moisture and temperature profiles

Intensive observation of pressure head by using tensi-

and surface fluxes in detail (Ishidaira et al., 1998). Re-

ometers in subsurface water and sampling of subsurface

garding to heat flow, thermal diffusion in soil is calcu-

water at multiple depths were performed to investigate

lated with fine vertical resolution by introducing the ther-subsurface flow process in monsoon season, 1998. The

mal conductivity and the heat capacity which are consid-

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GAME Letter No. 4

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May 2002

ered as the function of volumetric water content. The

tially averaged soil moisture is smaller than actual one

ground surface temperature is calculated by surface heat

under dry condition and larger under wet condition. Thebalance and is used as the upper boundary condition. The

effects of the wide range of the soil moisture distribution

water transport is expressed by a 5-layer soil model, indue to the presence of detention storage in the Tibetan

which the water budget is calculated by using the change

Plateau is expressed by a linear function of the standardof liquid water in the layer, the amount of water transport

deviation of soil moisture (Hirose et al., 2000). This re-

between layers, the change of liquid water content asso-

sult suggests a method for scaling up heterogeneous landciated with thawing and freezing of permafrost and thesurface processes.

deifference of the hydraulic conductivity and in the soil

4.4 Remote Sensing

matrix potential.

Due to the dynamics and constantly changing behavior

To consider the soil moisture – micro-topography inter-of the parameters inherent to energy and water cycle pro-action, a detention storage component, which affects on

cesses, and because of the relatively few ground observa-

the surface energy budget, was added into the one-dimen-tion stations over the Tibetan Plateau, efficient monitoringsional model (Hirose et al., 2000). The performanceand continuity in space and time sampling over the com-check of the soil moisture-microtopography interaction

plete plateau are only possible by satellite remote sens-

component was done, and indicated the variability of sur-ing. In turn, the field observations and process studies help

face soil moisture that is consistent to the observed one.

to serve as sources of ground-truth information for satel-

4.3.2 Two- and three-dimensional meso- and regional-

lite-based retrieval algorithms. To meet the objectives ofscale modelingthe process and modeling studies reported above, GAME-

To simulate the seasonal variation of the diurnal cycle ofTibet focused on the development and validation of satel-the cloud activities over and around the plateau derived bylite algorithms for precipitation, radiation budget, surface

GMS, Regional Atmospheric Modeling System (RAMS) de-fluxes, soil moisture and snow.

veloped at Colorado States University (CSU-RAMS) was

4.4.1 Precipitation

applied in two dimensions domain with north-south di-

Quantitative estimation of spatial distribution of pre-rection (17N-42N, 90E) (Kurosaki and Kimura, 2001).

cipitation in the Tibetan Plateau is one of the important

The characteristic diurnal cycles of cloud, less or no cloud

aspects for understanding the function of water cycle pro-in the morning of the pre-monsoon period and low-level

cesses and estimation of water resources. Ueno et al.

cloud in the morning of the monsoon over the Tibetan(2001) developed an SSM/I algorithm for rainfall by in-

Plateau, and frequent low-level cloud over the southern

troducing a new scattering index into the existing scatter-slope of Himalayas, were simulated well.

ing algorithm detect the weak intensity of precipitation in

Yoshikane et al. (2001) conducted numerical experi-

the plateau. The accumulated monsoon precipitation dis-ments to investigate the mechanism of the Baiu front bytribution in 1998 obtained by the new algorithm shows

using CSU-RAMS. The location of the Baiu front is specu-

better agreement with the GMS estimated precipitation

lated to be quite sensitive to the zonal mean flow. The

in the plateau area without screening of the surface con-

Baiu front accompanied by the low level jet was also represented by numerical experiments without topography,
which suggests that the Baiu front could be reproducedby two factors alone, the zonal mean field and the land/sea contrast. The orography, including the Tibetan Plateau,intensifies the precipitation of the Baiu front, especiallywhen the upper-level jet is weak and located northword.
4.3.3 Development of methods for scaling up land surface process models

dition.
A new algorithm for precipitation over land by deriving
the optical thickness from the brightness temperature of
the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) (Fujii and Koike, 2001). The effect of land surface controlled by soil moisture emissivity on radiation transfer is taken into account in this algorithm. This means that soil moisture can be estimated at

Due to the non-linear relationship between evaporation

the same time in addition to precipitation. Based on aand soil moisture, calculated evaporation by using spa-

microwave radiative transfer equation, two indices, Index

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GAME Letter No. 4

of Soil Wetness (ISW) and Polarization Index (PI), whichradiation due to the high elevation and the land cover con-remove the effect of land surface physical temperature,

dition.

are introduced into the algorithm. Surface roughness ef-

4.4.3 Soil moisturefects on land surface emissivity are included by using the

A new algorithm based on microwave radiative transfer

polarization mixing ratio and the surface roughness. As

theory was developed for soil moisture using passive mi-

the results of the algorithm application to the GAME-Ti-

crowave sensors (Koike et al., 2001a). It was applied to

bet meso-scale experimental field, the estimated opticalthe data from the TMI and evaluated by using the field

thickness and soil moisture are in good agreement withdata obtained during the IOP (Koike et al., 2001b). The

the patterns of precipitation observed by the 3D Doppler

estimated soil moisture corresponds reasonably to the soil

radar, and the observed soil moisture at 4 cm in depth,

moisture observed by the TDR sensor at 4 cm in depth.

respectively. A unique relationship between the optical

Just after the heavy rainfall, the satellite derived soil mois-

thickness and the observed precipitation by rain gauges

ture is greater than the ground observations because thecan not be seen due to the emission from precipitation

TMI only detects the surface moisture, which is muchlayer, the temporal sampling of TMI observation, and thewetter than the observations at 4 cm depth. Conversely,

profiles of hydrometeors. A reasonable relationship be-during dryer periods the algorithm underestimates because

tween the estimated optical thickness, and observed pre-the soil surface dries more rapidly. The monthly averaged

cipitation by rain gauges is obtained after 10 days of longer

diurnal cycle of the land surface physical temperature

temporal averaging.

calculated by the proposed algorithm shows the same pat-

We can produce the diurnal cycle of rainfall because

tern as the ground observations, however with several K

the TRMM satellite has a non-sun-synchronous orbit.

bias. The estimated water content of the vegetation also

Area-averaged rain rate, averaged storm height, propor-

corresponds well to the observations, with an accuracy oftion of convective rain to all rain in the rectangular area,

10% or less.

and the rain area to the rectangular area were calculated

A time series data from the Japanese Earth Resourcesfrom the TRMM Precipitation Radar (PR) data. This rect-

Satetlite-1 (JERS-1) Synthetic Aperture Radar (SAR) at L-

angular area almost covers the overlapping area of theband was used an algorithm for surface soil wetness at fine

Naqu hydrological basin and Doppler radar coverage. To-

spatial resolution by using surface roughness measure-tally 87 snapshots of rainfall events were obtained byments during the POP and a microwave backscattering

TRMM PR during the IOP. The results indicate that pre-model (Tadono et al., 2000). A surface roughness map

cipitation with a high storm height developed in the after-

was generated by the JERS-1 SAR winter data by applying

noon while the rain area was not large. In contrast, large

the scattering model and the relationship between two

startiform precipitation developed in the evening and nightsurface parameters under the perfectly dry condition. A

and the largest amount of rainfall appeared in the night

soil moisture distribution in summer was estimated by(Shimizu et al., 2001).

applying the scattering model and the surface roughness

4.4.2 Radiation budget and surface fluxes

map to a summer SAR data. The estimated distributions

Estimation of the energy exchange distribution betweenof soil moisture in the Tibetan plateau qualitatively cor-the land and atmosphere is one of key issues of the GAME-

respond to those obtained by field measurement.

Tibet project. The fluxes of radiation, soil heat, sensible

4.4.4 Snowheat and latent heat were estimated by combining the in-

An algorithm for snow was developed by a relationshipsitu data, NOAA14 Advanced Very High Resolution Radi-

between the land surface radiation and snow properties

ometer (AVHRR) data and the radiation transfer model,

derived from the radiative-transfer theory on a scattering

MORTRAN (Ma et al., 2001). The results show that 1)

dielectric layer over a homogeneous half-space. The to-the very wide range of fluxes due to the complex surface

tal land surface brightness temperature is the sum of theconditions, 2) the estimated components of energy bud-direct component and diffuse component, which corre-

get are in good agreement with the observed ones except

sponds to the reflected sky radiation and the thermal ra-

the latent heat flux at one site, 3) the large value of the net

dio emission from the snowpack and soil, and the radia-

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tion scattered from the direct and diffuse fields, respectively. By assuming snow grain size, snow density, and radiation from the soil-snow interface, brightness temperatures at two different frequencies, 19 and 37 GHz, were
calculated by inputting snow depth and physical temperature. This algorithm was applied to the data from the TMI
and evaluated by using the field data obtained in the winter of 1997-1998 (Koike et al., 2001a).The estimatedsnow physical temperature is in good agreement withground observations made with infrared thermometers.
Snow depth was not validated because of the lack of adequate ground observations.

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Shimizu, S., K. Ueno, H. Fujii, H. Yamada, R. Shirooka, and L.
Liu, 2001: Mesoscale characterictics and structure of stratiform precipitation on the Tibetan Plateau, J. Meteor. Soc.
Japan, 79, 435-461.
Shirooka, R., H. Yamada, H. Uyeda, J. Horikomi, 2001: Vertical
Structure of Connective Clouds Obtained by a Doppler Radar on Tibetan Plateau, Proc. 2nd Int. Workshop on TIPEX/GAME-Tibet, Kunming, China, (in press).
Tadono, T., T.Koike, J.Shi, Y.Ding, X.Chen, S.Wang, M.Yang, 2000:
Development of an algorithm for soil moisture mapping basedon single-parameter SAR images in permafrost regions including the effect of surface roughness, Journal of
Hydroscience and Hydraulic Engineering, 18, 29-38.
Tamagawa, K., Koike, T., and Fujii, H., 2001: An Introduction to
GAME-Tibet Data Information System(DIS), Proc. 2nd Int.
Workshop on TIPEX/GAME-Tibet, Kunming, China, (inpress).
Tanaka, K. and H. Ishikawa, 2001a: Estimation of Soil Heat Flux
Using in Situ Soil Parameters, Proc. 2nd Int. Workshop on
TIPEX/GAME-Tibet, Kunming, China, (in press).
Tanaka, K. and H. Ishikawa, 2001b: The Bulk Transfer Coefficient and Surface Roughness Length in the Eastern Tibetan
Plateau Using GAME/IOP Data, Proc. 2nd Int. Workshop

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GAME Letter No. 4

on TIPEX/GAME-Tibet, Kunming, China, (in press).
Tanaka, K., H. Ishikawa, T. Hayashi, I. Tamagawa, and Y. Ma,

Tibet estimated by satellite data during 1993 monsoon season. J. Meteor. Soc. Japan, 76, 533-548.

2001c: Surface energy budget at Amdo on Tibetan Plateau
using GAME/Tibet IOP98 data, J. Meteor. Soc. Japan, 79,

Ueno, K., H.Fujii, N.Grody, R.Ferraro, A.Gruber, 2001: Estimationof Precipitation with Weak Intensity in the Tibetan Plateau505-517.
Tanaka, K. and H. Ishikawa, 2001d: Long term monitoring of sur-by Using SSM/I Satellite Data, Proc. 2nd Int. Workshop
on TIPEX/GAME-Tibet, Kunming, China, (in press).

face energy flux at Amdo in eastern Tibetan Plateau, Proc.
of Int. Workshop on GAME-AAN/Radiation, Phuket, Thai-

Uyeda, H., H.Yamada, J.Horikomi, R. Shirooka, S.Shimizu, L.Liu,
K.Ueno, H.Fujii, and T.Koike, 2001: Characteristics of con-land, (Bull. Terrestrial Environ. Res. Cen., Univ. Tsukuba,
No.1 (GAME Publication No.28)), 40-43.

vective clouds observed by a Doppler radar at Naqu on Tibetan Plateau during the GAME-Tibet IOP, J. Meteor. Soc.

Tian, L., T. Yao, A. Numaguti, M. Tsujimura, and S. Hashimoto,
1999: Stable isotope in precipitation and monsoon activity inthe middle of Tibetan Plateau, Proc. 1st Int. Workshop on
GAME-TIBET, Xian, China, 59-63.
Tsujimura, M., A. Numaguti, L. Tian, S. Hashimoto, A. Sugimotoand M. Nakawo , 2001: Behavior of Subsurface Water Revealed by Stable Isotope and Tensiometric Observation in
the Tibetan Plateau. J. Meteor. Soc. Japan, 79, 599-605.
Tsukamoto, O., H. Ishikawa, S. Miyazaki, J. Kim, Y. Ma and Z.
Hu, 2001: Diurnal Variation of Surface Fluxes and Bound-

Japan, 79, 464-474.
Wang, J., 2001: Surface flux measurements in GAME/Tibet 1998,
Proc. 2nd Int. Workshop on TIPEX/GAME-Tibet, Kunming,
China, (in press).
Xu, J., and Haginoya, S., 2001: An Estimation of Heat and Water
Balances in the Tibetan Plateau, J. Meteor. Soc. Japan,
79, 485-504.
Yoshikane, T., F. Kimura, S.Emori , 2001: Numerical study on theBaiu front genesis by heating contrast between land andocean, J. Meteor. Soc. Japan, 79, 671-686.

ary Layer over Tibetan Plateau, Proc. Int. Workshop on
GAME-AAN/Radiation, Phuket, Thailand, (Bull. Terrestrial
Environ. Res. Cen., Univ. Tsukuba, No.1 (GAME Publication No.28)), 36-39.
Ueno K., 1998: Characteristics of plateau scale precipitation in

AAN Report[Heat budget group]
1. Background and General Information
The Eurasian continent plays a predominant role on
the seasonal cycle of the planetary-scale surface energy
exchange and transport in the climate system. The diverse
land surfaces and vegetation characterize the extremely
large seasonal and spatial variation of surface sensible andlatent energy fluxes over the continent, which in turn may
produce the regionality and asymmetries in the seasonal
cycle over the continent. Despite its importance, available basic data have been quite limited to study these issues. To remedy this situation, at least partially if not completely an automatic weather station (AWS) which has acapability to measure not only the regular meteorological and hydrologic variables but also surface fluxes ofmomentum, heat, water vapor and radiation as well as soil
moisture status, have been installed over the Asian countries since 1996 as a part of GAME activities. Currently
15 stations are in operation (see Fig.1) and valuable data

Fig. 1 A map showing the location of GAME-AAN flux
stations currently in operation. Triangles indicate
those stations expected to operate through phase
II of GAME-AAN, while circles represent thosethat will operate only during phase I.

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9May 2002

have been accumulated and analyzed in the framework ofsystem was installed in 2000-2001 for a reliable long-

GAME-AAN project. Currently, the project is in the be-term measurements.

ginning of its Phase II (Monitoring phase) which has- The AAN data

started in the year 2000, and this will be the period for a

The data have been, and will be, checked and processedlong term monitoring to determine mean, seasonal andas they are provided from each station for archiving at theannual variations of surface variables. Phase I (Installa-

AAN data center at Terrestrial Environment Research Cen-tion phase) had been for the development of the AWS sys-

ter of the University of Tsukuba. Each station has four

tem and initial study period.

types of dataset within the data archives. They consist of

2. Phase I activity summary(i) the station documentation, (ii) the dataset documenta-- AWS test and operation

tion, (iii) the data inventory and (iv) actual dataset. To

As mentioned, Phase I has just been completed. In

produce these datasets and to provide them in AAN data

general, initial plan of the test and installing AWSs incenter have the responsibility by PIs of each station. At

GAME areas achieved as planned. However, there werethe moment, for most stations (i)-(iii) are available (seeproblems, both expected and unexpected, that interrupted

Fig. 4-6 as examples), through the AAN website (http://

field measurements and resulted in unavailability of rel-www.suiri.tsukuba.ac.jp/Project/aan/aan.html). The actual

evant data during the intensive observation periods ofdata (iv) are now being distributed within the GAME com-

GAME in some areas. Problems came from probably two

munity for the 1998 data sets, and will soon be open to a

separate reasons. First one is that in AWS systems, par-wider scientific communities based on GAME data policy.

ticularly PAM III station developed and produced by Na-

However, there are some stations which lack an adequate

tional Center for Atmospheric Research in the U.S. aredescription of the data sets or the station. There are also

very sophisticated and require a careful maintenance andsome station which has not produced complete data sets

operation, although they have strong capability to produce

from the original measurements. These variables oftenvery accurate measurements with a modest cost when

include the latent and sensible heat fluxes which require acompared with other AWS systems. Although we could

careful quality check of the data and processing of the

get a long term data of turbulent fluxes through direct mea-

measured values before they can be used with confidence.

surements with the PAMIII when it works well, unfortu-- Scientific Issues

nately we had more missing data than the other AWSs (seeTo summarize and wrap-up the Phase I activities andFig.2 and Fig.3). Most of the missing data was caused by

to address future needs of AAN activities, the International

the unstable and incomplete system of data acquisition

Workshop on GAME-AAN/Radiation was held at Phuket

system of PAMIII, while most of sensors were workingin Thailand on March 7-9, 2001 with about 100 partici-

properly. Some other reason for such trouble is that inpants and 40 oral presentations. Some of presentations

GAME scientists and local counterpart personnel to op-

were already published to scientific journals (e.g., Aoki

erate AWS systems did not have adequate time to get ac-

et al., 1998; Ohta et al., 1999, 2001; Toda et al., 2001).

customed to the system due to the quite complicated sys-

Below some important topics discussed in this workshop

tems. Thus when a technical problem occured in someare summarized as follow:

remote area, it took a long time to solve it. These prob-

One of the issues that has emerged in the process oflems, however, have occurred gradually less frequently

deploying AWSs and the data analysis is the so-called en-

and continuous measurements become more common at

ergy imbalance problem. Theoretically, the sum of latent

some stations, after we modified the system of PAMIII

and sensible heat fluxes should be balanced with net ra-

based on the discussions between NCAR and GAME sci-diation and soil heat flux. However, in many AAN sites

entists in the workshop held at Boulder, U.S. in July, 1999

this turned out not to be the case, although some sites(see detail in our website: http://www.suiri.tsukuba.ac.jp/

reported close to perfect balance (see Fig.7). Current

Project/aan/meeting-ws/ws-PAM99.html). Both GAME

consensus appears that the closure problem is site spe-scientists and counterparts have got a better knowledgecific and that up to 20-30% of the net radiation may notof the system and an additional backup data acquisition

be able to accounted for from measurements. Possible

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GAME Letter No. 4

reasons have been identified as a problem of turbulence

equate funding and resources for the operation are undermeasurements technique, sampling error of the soil heatconsideration.

flux and the net radiation measurements, and a mismatch

In addition to the continuation of the measurements,of foot print of equipments used to measure energy bal-an urgent task to be made is to update and complete theance components. Intensive discussions at scientific

AAN data sets. This should include strong efforts of themeetings, both at the international workshop and other

AAN data center to obtain the data and the derived values

related meetings, took place, and as a result, an additionalby each PIs for distribution among the scientific commu-

field observation initiative has started in which 5-10 eddy

nities. Also, for those scientists who do not have easy

flux measurement systems were installed side by side at aaccess to the Internet, data distribution by some medias

well maintained and controlled site, and their difference,(e.g., CD-ROMs) are also being considered.

and possible causes for the imbalance problems are being
investigated.

References

Although Phase I is for the test and deployment of

Aoki, M., T.Chimura, K. Ishii, I. Kaihotsu, T. Kurauchi, K. Musiake,

AWS systems, some initial results of a long term mea-

T. Nakaegawa, N. Ohte, P. Panya, S. Semmer, M. Sugita,
K. Tanaka, O. Tsukamoto, and T.Yasunari, 1998: Evaluation

surements are being reported. Figs.8-9 which indicatesthat three geographically very different locations showed
difference in variations of surface energy partition regime,
both in time and in magnitude (Miyazaki et al., 2001).
Additionally, some interesting and encouraging results were reported with the Phase I AAN data set. Figs.
10 and 11 illustrate such two examples. Figs.10 and 11
give comparisons of the surface fluxes obtained from one
AAN surface station and from GAME and ECMWF reanalysis data (Yatagai et al., 2001). For the reanalysis data,
flux values of the nearest grid were used. The comparison
indicates reanalysis very good agreement of the measurements and model derived values. This tends to indicate, inthe viewpoint of the surface station, that a point measurement of the station represents somehow a region surrounding the station. This is encouraging for the use of the
AAN data and actually may not be too surprising given thefact that each station site was selected so as not to be too
local and not to be too different from its surrounding areas. Fig. 12 illustrates one example of the use of AAN
data for the model validation (Sugita et al., 2001, Sugita,
2001). Because AAN sites cover a wide range of geographical areas and climates, a comparison of any variables produced from a model or from a satellite against
the AAN data sets should give opportunity for a thoroughvalidation of these data (and, in turn, the model or the satellite measurements themselves).
3. Future Plan
Curretly 9 stations are planed to keep operation
through Phase II of the AAN to obtain a long-term trendof surface variables. At the moment, proposals to get ad-of surface fluxes over a paddy field in tropical environment:
Some findings from preliminary observation of GAME, J.
Japan Soc. Hydrology & Water Resour., 11, 39-60.
Ma, Y., O.Tsukamoto, I.Tamagawa, J.Wang, H.Ishikawa, Z.Hu and
H.Gao, 2000: The study of turbulence structure and transfer
characteristics over the grass land surface of Tibetan Plateau, Chinese J. Atmos. Sci., 24, 456-464.
Miyazaki, S., O.Tsukamoto, M. Toda, N. Ohte, K. Tanaka, I.
Kaihotsu, T. Miyamoto, and T. Yasunari, 2001: A comparative study of seasonal variation of surface heat flux in Asian
Monsoon region, Proc. Int. Workshop GAME-AAN/Radiation, GAME Public., No.28 (Bull. Terrestrial Environ. Res.
Cen., Univ. Tsukuba, No. 1), Pucket, Thailand, 95-97.
Ohta, T., K. Suzuki, Y. Kodama, J. Kubota, Y. Kominami and Y.
Nakai, 1999: Characteristics of the heat balance above thecanopies of evergreen and deciduous forests during the snowy
season, Hydrological Processes, 13, 2383-2394.
Ohta, T., T. Hiyama, H. Tanaka, T. Kuwada, T. C. Maximov, T.
Ohata and Y. Fukushima, 2001: Seasonal variation in the energy and water exchanges above and below a larch forest in
Eastern Siberia, Hydrological Processes, 15, 1459-1476.
Sugita, M., 2001: Estimation of large scale evaporation by a complementary relationship with a simple ABL model. Proc. Int.
Workshop GAME-AAN/Radiation, GAME Public., No.28(Bull. Terrestrial Environ. Res. Cen., Univ. Tsukuba, No.
1), Pucket, Thailand, 91-93.
Sugita, M., J. Usui, I. Tamagawa, and I. Kaihotsu, 2001: Complementary relationship with a convective boundary layer model
to estimate regional evaporation, Water Resour. Res., 37,
353-365.
Toda,M., N.Ohte, M.Tani and K.Musiake, 2001: Observation of
evergy flux and evapotranspiration over terrestrial complex
land in the tropical monsoon region, J. Meteor. Soc. Japan,(submitted).

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Yatagai, A., S. Miyazaki, M. Sugita, O. Tsukamoto, N. Ohte, M.
Toda, 2001: A comparative study of surface fluxes derived
from four-dimensional data assimilation products with AAN
observations. Proc Int. Workshop GAME-AAN/Radiation,
GAME Public., No.28 (Bull. Terrestrial Environ. Res.
Cen., Univ. Tsukuba, No. 1), Pucket, Thailand, 25-28.

Fig. 4 An example of the GAME-AAN data inventory
list as seen on the AAN web site.

Fig. 2 Time series of the data availability for basic
meteorological elements (e.g., air temp., precipitation, wind speed) obtained by ACOS (AutomatedClimate Observing system) and PAMIII. These
values were calculated by using raw data for ACOS
but processed data for PAMIII.

Fig. 5 Same as Fig.4 but for dataset documentation.

Fig. 3 Same as Fig.3 but for surface fluxes (sensible
heat flux, latent heat flux, momentum flux).

Fig. 6 Same ad Fig.4 but for station documentation.
Fig. 7 (left) An example of energy balance closure asreported from an AAN station located in Mongolia.

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Fig. 8 Seasonal variation of NDVI at three AWS locations as given with 20-year means. (see Fig.1 forthe exact location)

GAME Letter No. 4

Fig. 9 Seasonal march of evaporative fraction [=LE/(Rn-G), the ratio of latent heat flux and available
energy]Fig.10 Comparison of sensible heat flux (upper panel) and latent heat flux (lower panel) between GAME reanalysis Ver. 1.1, ECMWF operational dataset and AAN observation (EGAT tower at Tak in Thailand). Small
dots indicate AAN observation (every 30 minutes); triangles, GAME reanalysis; and circles, ECMWF operational dataset.

Fig. 11 Same as Fig. 10 but for the site of AAN observation (north PAMIII on Tibetan Plateau).

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data are being archived to provide surface shortwave andlongwave radiation budget at these sites.
3) Investigation of the effect of cloud and aerosol radiative
forcing. Direct and indirect climate effects of anthropogenic aerosols have become recent important topics
for improving the global warming simulation. Data fromthe sky radiometer network called SKYNET which includes GAME radiation sites and satellite radiance dataof AVHRR, SeaWiFS and MODIS have been analyzed
to derive the radiative properties of aerosols and clouds
useful to depict the aerosol climate effects.
The final goal of the radiation activity is to reduce uncertainties involved in the estimation of the earth and surface radiation budget, especially due to clouds and aerosols in the Asian region. The uncertainty of the radiation
Fig. 12 Comparison of model derived latent heat flux

budget coming from cloud and aerosol is said to be 20 to 30(LEs) and AAN measurements at Tak in Thailand

W/m2, which is 6 to 8 % of the total incoming solar radia-

during dry season (Sugita et al., 2001).

tion.
2. Activities of the GAME Radiation GroupIn order to pursue the previously mentioned three ob-[Radiation group]
1. Objectives of the GAME Radiation Study

jectives, the following activities have been performed.
- SKYNET and GAME high precision radiation Sites

Investigation of the earth’s radiation budget is impor-

The SKYNET is a network of a sky radiometer, whichtant for understanding the energy and water circulation

is similar to the NASA AERONET sun/sky photometer

processes in the GAME region. It is also important to study

network (Holben et al., 1998), to measure the sky radi-the impact of large scale air pollution in the Asian region toance distribution as well as the direct solar irradiances atunderstand the impact of anthropogenic aerosols to theseveral wavelengths from 360 nm to 1020 nm, from which

global warming phenomenon through investigation of theaerosol size distribution and optical thickness are re-radiative properties of aerosols and clouds (Emori et al.,trieved. A pynanometer is also required at the sites for1999). In this program, the following tasks are considered

measuring the downward solar radiative flux. SKYNET

to attain these researches:sites are shown in Fig. 1. Sri Samrong (Thailand, 16.9N,

1) Developing an accurate method to estimate the surface

99.8E, since July 1997), Shou-Xian(China, 32.6N, 115.8E

radiation budget from satellite data. The wide area distri-

until March 1999) /Hefei (China, 31.9N, 116.9E, frombution of solar insolation flux at surface is desirable toApril 1999) are the GAME-AAN High Precision Radia-

obtain from the GMS satellite data.

tion sites, where full instrumentation of the surface ra-2) Establishing an accurate radiation budget monitoring at

diation budget and cloud/aerosol measurements haveseveral sites in the GAME area for validation of the ra-

been installed. A lidar, and a microwave radiometer werediation budget derived from satellites. In this activity,

installed at Sri Samrong. Takayabu et al. (1999) studied

BSRN (WMO Baseline Surface Radiation Network) typethe radiation budget in Tsukuba with data from similar in-

instrumentation is introduced for accurate measurements

strumentation as shown above.

of the surface radiation budget. A microwave radiometer- Solar flux distribution from GMS satellite

and a sky radiometer instrumentation to retrieve the cloud

The surface solar radiation was estimated from GMS

and aerosol radiative properties which are indispensablevisible and infrared radiance data (Fig. 2) and compared

for theoretical simulation of the radiation budget. The

with the values observed at the GAME High Precision Radiation sites and SKYNET sites (Fig. 3). Monthly mean

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GAME Letter No. 4values of the surface radiation flux in 1997, 1998, and 1999

ponent) are dominant in the region to the north of 20N

are basically in good agreement with the observation. De-due to industrial sources located in the middle and hightailed comparison shows, however, a minor difference

latitudes. This is also reflected in the single scattering

which is considered to relate to the aerosol optical thick-albedo value observed by the Mirai cruise (Fig. 7). The

ness and the diffused light intensity. When the aerosol op-

northern area has a single scattering albedo as low astical thickness is large the surface radiation flux is cor-

0.8, whereas the subtropical and tropical area has a value

rectly estimated, but the satellite value underestimates theclose to the unity, indicating the effect of the black car-surface-measured value when the aerosol layer is thin. Thisbon is significant in the large area of the northern hemi-

suggests that an adequate introduction of aerosol loading

sphere.

is important for accurate estimation of the surface solar- Satellite remote sensing of aerosols and clouds

radiative flux from satellite radiances.
- Lidar measurements

An algorithm of retrieving the aerosol optical thickness and Angstrom exponent were developed (Higurashi

From the lidar monitoring, the cloud base height statis-

and Nakajima, 1999) and applied to channel 1 and 2 ra-tics was obtained. The results show that the cloud base height

diance data of AVHRR (Nakajima and Higurashi, 1998;

is dominant at around 1.5 km altitude and the cloud is de-

Nakajima et al., 1999b; Higurashi et al., 2000). It is

tected in 90 % cases in rainy season (July and August),

found that the resulted characteristic distribution ofwhereas clouds tends to be double layered with peak alti-

small-size and large-size aerosols are consistent withtude at 1.5km and at an altitude higher than 6 km in dry

model results from the aerosol transport model ofseason (Fig. 4).

Takemura et al. (2001) although the satellite-derived-Aerosol characterization by surface measurements

aerosol optical thickness somewhat overestimate theFrom the model simulation, it is known that each aero-model values due to cloud screening problem. The model

sol has a different effect to the earth radiation budget. Light

results, on the other hand, may have an error due to anabsorbing aerosols such as black carbon and soil dust aero-

uncertainty in the emission source assumption. The ra-sols have a warming effect, but other aerosols such as sea

diative properties of biomass burning aerosols were in-salt and sulfate aerosols show a cooling effect (Fig. 5). It isvestigated for the Indonesian forest fire event in 1997

important to obtain a large scale distribution of the aerosol(Nakajima et al., 1999a). The single scattering albedo

optical radiative properties, especially the single scatter-shows a value around 0.9 in this Indonesian case, which

ing albedo, to attain an accurate estimation of the radiativeis slightly larger to the Thailand biomass burning caseforcing of the direct effect of the anthropogenic aerosols.

shown in the previous subsection. This may be explained

In February, dry season in Thailand, the effect of biomass

that Indonesian aerosols included sulfate particles gen-burning was outstanding. The size distribution from the sky

erated from the peat bog burning.

radiometer, showed a large optical thickness and smaller

Cloud microphysical parameters were also retrievedsize distribution with smaller single scattering albedo thanin this study with the solar reflection method (Kuji etthose in rainy season (Fig. 6). Chemical analysis of sampledal., 2000; Kawamoto et al., 2001). The radiative forcing

aerosols gave a large black carbon (BC) concentration inof the indirect effect of anthropogenic aerosols was fur-the dry season, which is considered to be due to biomass

ther estimated by Nakajima et al. (2001) using the cor-burning. The large absorption by black carbon is reflected

relation between aerosol and low cloud microphysicalin the single scattering albedo as low as 0.75 in the begin-parameters derived from AVHRR remote sensing. It isning of the period, whereas the single scattering albedo
started reaching 0.9 when the optical thickness becomes

found, for example, the columnar aerosol number density has a correlation with that of low clouds as ? log10

small in the latter period.

Nc 〜〜 0.5 ? log10 Na. These correlations thus obtained

The radiative properties of aerosols were also moni-give an estimate of the indirect forcing of anthropogenic

tored in the West Pacific region in a cruise of the researchaerosols as RF= -0.7 to -1.7 W/m2 over ocean.

vessel Mirai. The latitudinal dependence of the aerosol size

3. Future Prospect

distribution shows that fine particles (larger Angstrom ex-

More comparison between surface radiative flux ob-AME

GAME Letter No. 4

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May 2002

served at the radiation sites and satellites is required inorder to reduce the uncertainty in the surface radiationbudget. Model calculations of the surface radiation budget with the radiative properties of aerosols and clouds
retrieved from surface and satellite measurements are also
important to understand the role of clouds and aerosols
to determine the radiation budget. The vertical structureof aerosol and cloud stratification observed by lidar data
should be incorporated with such analysis and model calculation of the surface radiation budget, especially for the
longwave radiation. From a logistic view point, we needmore stable instrumentation at the existing radiation sites
to generate long-term and complete data sets from all the
instruments. We may need 2 to 3 more stations to cover
the GAME region for the radiation studies. Developmentof aerosol remote sensing over land is one of high priority issues to pursue. In this regard it should be pointed outthat the recent TERRA/MODIS aerosol product over land
will be useful to be combined with the GMS retrieval algorithm of the surface radiation budget, because it is foundthat a suitable aerosol loading should be introduced in the

retrieval algorithm. Data from the coming satellites,
ENVISAT, AQUA, and ADEOS-II, will increase our ability for retrieving the earth and surface radiation budget aswell as the global distribution of aerosol and cloud parameters (T.Y. Nakajima, 1998; King et al., 2000; Kuji
and Nakajima, 2001).
Major publication list for the contribution to the
GAME radiation studies (1998-2000)
Emori, S., T. Nozawa, A. Abe-Ouchi, A. Numaguti, M. Kimoto
and T. Nakajima, 1999: J. Meteor. Soc. Japan, 77, 12991307.
Higurashi, A., and T. Nakajima, 1999: J. Atmos. Sci., 56, 924-941.
Higurashi, A., T. Nakajima, B. N. Holben, A. Smirnov, R. Frouin,
B. Chatenet, 2000: J. Climate, 13, 2011-2027.
Holben, B. N., T. Nakajima, et al, 1998: Remote Sens. Environ.,66, 1-16.
Kawamoto, K., T. Nakajima, and T.Y. Nakajima, 2001: J. Climate,14, 2054-2068.
King, M. D., Y. J. Kaufman, D. Tanre, and T. Nakajima, 1999:
Bull. Amer. Meteorol. Soc., 80, 2229-2259.
Kuji, M., T. Hayasaka, N. Kikuchi, T. Nakajima and M. Tanaka,
2000: J. Appl. Meteor., 39, 999-1016.
Kuji, M., and T. Nakajima, 2001: SPIE, 4150, 225-234.
Nakajima, T., and A. Higurashi, 1998: Geophys. Res. Lett., 25,3815-3818.
Nakajima, T., A. Higurashi, N. Takeuchi, and J. R. Harman, 1999a:.
Geophys. Res. Lett., 26, 2421-2424.
Nakajima, T., A. Higurashi, K. Aoki, T. Endoh, H. Fukushima, M.
Toratani, Y. Mitomi, B. G.
Mitchell and R. Furuin, 1999b: IEEE Trans. Geosci. Remote Sensing., 37, 1575-1585.
Nakajima, T., A. Higurashi, K. Kawamoto, and J. E. Penner, 2001:
Geophys. Res. Lett., 28, 1171-1174.
Nakajima, T. Y., T. Nakajima, M. Nakajima, H. Fukushima, M.
Kuji, A. Uchiyama, and M. Kishino, 1998: Appl. Opt., 3,3149-3163.

Takayabu, Y.N., T. Ueno, T. Nakajima, I. Matsui, Y. Tsushima, K.
Aoki, N. Sugimoto, and I. Uno, 1999: J. Meteor. Soc. Japan, 77, 1007-1021.
Takemura, T., H. Okamoto, Y. Maruyama, A. Numaguti, A.
Higurashi, and T. Nakajima, 2000: J. Geophys. Res., 105,
17853-17873.

Fig. 1 Radiation observation sites.

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Fig. 2 Surface solar radiation was estimated from
GMS data.

GAME Letter No. 4

Fig. 3 Comparison of monthly solar radiation flux
from the ground measurement and GMS data.

Fig. 4 Histogram of cloud height observed by lidar.
Fig. 5 Aerosol direct radiative forcing (annual mean).

Fig. 6 Aerosol size distribution.
Fig. 7 Aerosol characteristics in the Western Pacific.

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Summary of GAME modelling activities
1. Introduction
When the GAME was started, the objectives of themodelling component was defined as follows;

3. Two dimensional study- Relation between orography and convection by twodimensional RAMS
Sataomura (2000) investigated the diurnal variation

1) By conducting the flux observations in the various re-over the Indo-China Peninsula using the two-dimensional

gions over the Asian Monsoon area, we can develop/

RAMS, which is a nonhydrostatic cloud-resolving numeri-

improve a land-atmosphere interaction scheme, which

cal model. He found out that solar-synchronized life cycle

is now used in GCM.

of the squall lines and their eastward movement cause the2) By applying the improved parametarization scheme, wenighttime maximum of the precipitation over the inland

can improve the prediction skill of the atmosphericarea of the Peninsula, which has been actually observed.

flow and precipitation in the Asian Monsoon region.

Kurosaki and Kimura (2001) carried out some two-3) Based on the improved models described above, we

dimensional numerical experiment over a cross-section

can contribute to the improvement of seasonal pre-over Himaraya and Tibetan Plateau (Fig.1). The model

diction and water-resource management, and present

shows the clear diurnal variation of convective clouds overthe detailed information about the change of watersome dominant mountain ranges in the Plateau, which

cycle in the Global Warming situationagree well with the satellite observations.

In order to achieve these objectives, the research activities were organized in the three components;

4. Three dimensional study4) One dimensional study: the land-atmosphere interac-

GCM study has been conducted by using the CCSR/

tion is investigated by comparing the observations con-

NIES GCM. As you may expect, it is impossible that theducted in the GAME IOP and the various models suchnew scheme is proposed immediately after the IOP was

as SiB2 and the bucket model.

over. Then, emphasis is placed on the understanding of5) Two-dimension study: the land-atmosphere interaction

the atmosphere-land interaction by using the present

is investigated by using the non-hydrostatic meso-scale

CCSR/NIES GCM. Regional and mesoscale modeling aremodel such as the RAMS and the NHM developed atalso conducted using RAMS and other numerical models.

the NMI/JMA. Emphasis is placed on the interaction
between detailed orography and convection.

- 1997 and 1998 Asian Monsoon Study6)Three-dimensional study : the land-atmosphere inter-1997 and 1998 was the El-Nino year and the influ-

action is investigated by using the CCSR AGCM andence of the El/Nino to the Indian Monsoon was investi-

the CCSR/NIES Climate model.

gated by Xhen and Kimoto (1999). Besides that, it was

It should be noted that research relating to study 4)

the abnormal year when the heavy rainfall occurred in theand 5) is conducted in the regional studies of the GAME

Yantzen River. This topic was investigated by using theactivities and many results are described in the other sec-

1998 SST. It is concluded that SST in the Indian Ocean

tions. Here, we will briefly summarize the achievement

has a strong effect on the anomouraous precipitation overof the modelling component.

the Asian region (Kimoto et al., 2000).

2. One dimensional study- Sensitivity study to the horizontal resolution for the- Evaluation of SiB2

atmosphere-land interaction

Takayabu(MRI/JMA) are collecting observational data

Atmosphere - land Interaction Sensitivity to the hori-from the regional experiments and making a standard data

zontal resolution is now being conducted by using T42

set for comparising and evaluating the one dimensional

and T106 CCSR/NIES AGCM . The simulation was stared

flux schemes. He compared the observed data in the Tibet

from the April 1, 1998 and integrated until the end of Au-

by the SiB2 result.

gust. Sensible and latent fluxes and precipitation in thetwo models were compared over the different regions,such as the Tibetan lateau (80-100E,27.5-35N),Thai (100-

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18

May 2002

106E,15-20N) and China (115-120E,30-35N). Over the2

GAME Letter No. 4eling, SiBUC (the Simple Biosphere Model including Ur-

Tibetan region, difference are about 20 W/m in the

ban Canopy) has been progressed in Kyoto University. A

monthly mean. The large differences are noted in May,

coupling experiment of SiBUC with a mesoscale atmo-

which are due to the differenece of the large scale flow.

spheric model was performed. To simulate movement

In China, a large difference of precipitation is noted inof ground water, a runoff model also has developed.

2

June. However, difference of fluxes are about 20 W/m in

Simulation experiment of water discharge using the run-these areas. In order to estimate the differenecs due to theoff model showed good an agreement between simulated

internal fluctuation of model simulation, the ensemble

and observed runoffs.

experiment will be conducted.

In the meteorological modeling study, a mesoscale
simulation using JSM (the Japan Spectral Model ) which- Sensitivity study to the land scheme for the Asian Mon-was developed by the Japan Meteorological Agency hassoon Flowbeen performed to study a regional water cycle and pre-As it takes some time for the new scheme to appear,

cipitation.

we decided to use the other scheme developed at other

Cloud and precipitation studies are the most impor-place. We has chosen the MATSHIRO, which is now be-tant objectives in HUBEX. In order to study dynamics

ing developed by the researchers in Japan. Now theand evolution of convective clouds over the China conti-

MATSHIRO model is being implemented and tested. Af-

nent, we now develop the Cloud Resolving Storm Simu-

ter that, simulation study will be conducted.

lator (CReSS). We performed the simulation experimentof the observed squall line using CReSS with very high- Baiu/Meiyu Front and heat contrast between Asian

resolution in a large three-dimensional domain. The in-continent and Ocean

homogeneous initial field was given by the dual Doppler

Yoshikane et al. (2000) clarified one of the formation

radar observation and the sounding. The experimental

mechanism of the Baiu Front. By a regional climate model,

design is as follows. The horizontal and vertical grid sizes

they showed that one of the most important mechanism of

were 300 m and 300 m, respectively with a domain of

the Baiu Front is the heating contrast between land and

170 km × 120 km. Cloud microphysics was the cold rain

ocean. The Baiu Front can be formed only by the interac-type. The boundary condition was the wave-radiating type.

tion between global scale zonal mean flow and the con-

The result of the simulation experiment shows that CReSS

trast between them. Surface moisture of the Asian conti-

successfully simulated the development and movement

nent may affect the position and intensity of the Baiu Front.

of the squall line (Fig.2). The convective reading edge
was maintained by the replacement of new convective- Hydrological and Atmospheric Modeling Studies incells and the simulated squall line moved to the north-

HUBEX

east which is similar to the behavior of the observed squall

The modeling study of HUBEX (the Huaihe River Ba-

line. Convective cells reached to a height of about 14 km

sin Experiment) includes hydrological and meteorologi-

with large production of graupel above the melting layer.

cal modelings. In particular, their coupling and water cycle

The rear inflow was significant as the observation. A strati-

modeling experiment using a coupled model are mostform region extended with time behind the leading edge.

important objectives of HUBEX. In the hydrological mod-Cloud extended to the southwest to form a cloud cluster.

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GAME Letter No. 4

19

May 2002

Fig. 1 Vertical cross-section of potential temperatur

Fig. 2. Horizontal displays of the simulated squall(broken lines), liquid/ice water content (thin lines)

line (left panel) and the observed squall line

and precipitation (bars) at 1500 LST over(right panel) at 1204UTC, 16 July 1998. Gray lev-

Himaraya and Tibetan Plateau, simulated by theels indicate total mixing ratio (g/kg) of rain, snow

two-dimensional RAMS. Grid interval is 2 km.

and graupel in the left and radar reflectivity (dBZ)
in the right. Arrows are horizontal velocity.

Report on the GAIN activity
Kiyotoshi Takahashi (MRI)

tional research communites. We finally reached the following agreement.
Data obtained as part of the observations during the

GAIN is an abbreviation of Game Archive & Informa-

IOP will be made available according to the following

tion Network. Its function is divided into two parts, thatschedule.

is, establishment of the GAME data management policy

1) By the end of June 1999 (6 months after the IOP), forand construction of the system that disseminates GAME
data and information.
The first work as GAIN was to work out the GAME

the participating institutes and scientists.
2) By the end of June 2000 (one year later), for the international research community.

data management policy. GAME is an international research

Data obtained as part of the GAME observations dur-

project, so international cooperation is crucial for its suc-

ing the non-IOP will be made available according to thecess. The data policy is the base of such an international

following schedule.

cooperation, and gives the guideline for various aspect con-

3) By the end of one year after the observation, for thecerning the GAME data, for example, definition of the
GAME data and basic strategy of data provision, and soon. The original draft of the data policy was prepared mainly

participating institutes and scientists.
4) By the end of two years after the observation, for theinternational research community.

by the late Dr. M. Murakami, and was proposed in the 2nd
GAME International Science Panel for the first time. Fi-

At present (April 2001), the GAME data basically havenally this GAME data policy was adopted at the 3rd GISP

been open to the international research communities af-

in January 1998 just before the GAME IOP(Intensive Ob-

ter June 2000 according to the above-mentioned agree-

servation Period).

ment. But it is delayed for the HUBEX data and some

One of an important matter in this data policy is thepart of data concerning the Tibetan plateau (TIPEX,

time schedule of the GAME data release to the interna-

JEXAM) to be open due to their local data policies.
However they are also going to be open until the summer

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20

May 2002

of 2001, three years after their observation.
In addition, recently we requested supplementary data
(surface station data) mainly to the southeast asian coun-

GAME Letter No. 4duce CD-ROMs for other GAME data resources because
CD-ROMs are very useful in the case that the online access is unavailable.

tries to use the validation of the GAME Reanalysis data.

As mentioned in the above, the GAIN system is al-Some countries kindly provided us the data in response tomost successfully being operated. However all GAME

our request.

data haven't yet been accessible. We need to complete theNext, we will move onto the second function of GAIN.

GAIN system in a hurry as soon as possible.

In the data policy main means for data provision is planned
to be the online access via Internet, and each sub-projectgroup is requested to have his own responsibility in data
provision.
The GAIN system is composed of GAIN-hub and
GAIN-DAACs as shown in Fig. 1. The function of the
GAIN-hub is to offer catalogue information for GAME
data and some selected data, mainly GAME-reanalysis
data. Presently most of sub-groups have started to operate ftp or web sites for data dissemination since the summer of 2000. Everyone who is interested in the GAME
data can obtain data and information by starting from thisgain-hub (http://gain-hub.mri-jma.go.jp).
Besides the online provision, CD-ROMs were also
produced especially for GAME-Tibet and GAME-reanalysis, and distributed in the world. Now it is planned to proFig. 1 GAIN system

In 1998, we conducted the Intensive Observing Period

Toward GAME Synthesis(IOP) in cooperation with many Asian countries and the

Tetsuzo Yasunariinternational/national projects such as South China Sea
Monsoon Experiment (SCSMEX), Chinese Tibetan Pla-Institute of Geoscience, University of Tsukuba, andteau Experiment (TIPEX) and Korean Monsoon Experi-

Frontier Research System for Global Changement (KORMEX). The enhanced radiosonde observations,as well as surface hydrometeorological observations, were

1. Introduction

operated at more than hundred stations in the monsoon

Nearly five years have passed since GAME started in

Asian countries. We conducted the 4-dimensional data

1996. The regional experiments on energy and water cycle

assimilation (4DDA) of the atmospheric field over theprocesses have been conducted in Thailand (GAME-Trop-whole monsoon Asia, and the first version of this reanaly-ics), in the Huai-he river basin in China (GAME-Hubex),

sis data have been released as version 1 of GAME-reanaly-

in the Tibetan Plateau (GAME-Tibet) and in the Lena riversis. Some scientific results, particularly from GAME-

basin in Siberia (GAME-Siberia). The long-term radia-

Tropics and GAME-Tibet were reported in the special is-tion and energy fluxes in various sites of the monsoon

sue of Journal of the Meteorological Society of Japan

Asian region have been operated by the automatic weather(Yasunari, ed., 2001).

stations (AWS) as the Asian AWS Network (GAME-AAN).

These data obtained through the regional experiments,
AAN, including the reanalysis data for the IOP have been

AME

GAME Letter No. 4

21

May 2002

compiled and archived as part of GAME Information andPanel.

Archive Network (GAIN). Some data are being released
to the international science community under the data
policy of World Meteorological Organization (WMO).

3. Cloud and precipitation processes and large-scalemonsoon circulation

As documented in the GAME Letters (No. 3 and thisAnother key issue for the energy and water cycle ofletter), we have obtained various new scientific results on

monsoon Asia is cloud and precipitation processes andthe hydro-meteorological processes in the Asian monsoon

its interaction with large-scale atmospheric circulation.

region from the Tropics to the Siberian Arctic region.

In the GAME region, the interaction with the monsoon

Particularly, the land-atmosphere interaction processes

circulation, including the influence of surface topogra-

in some typical climate and vegetation in monsoon Asia

phy and vegetation is the most important process. As part

have been revealed in diurnal through seasonal time scales.

of GAME-Hubex and GAME-Tibet, the intensive obser-

Cloud and precipitation processes have also been scruti-

vation of the 3-dimensional cloud/precipitating systems

nized in the tropical region, the Meiyu-Baiu frontal zone

were observed by using the Doppler-radar systems, within the subtropical China and on the Tibetan Plateau area.

the enhanced radiosonde observations. The interaction

What we have to do now and from now is to synthe-

between the meso-scale cloud/precipitation systems andsize these scientific results to reach the final goals andthe large-scale monsoon circulation are being investigatedobjectives of GAME (GAME International Science Panel,

combining the objectively analyzed reanalysis data. The

1998). The fifth session of the GAME International Sci-regional 4DDA analysis for the Hubex region is plannedence Panel (GISP) held in June, 2000 in Tokyo proposed

for the detailed interactive processes between the meso-

the GAME Phase-II for further research, including datascale cloud systems and the ambient monsoon and west-

analysis, some additional process studies and modeling

erly flow regimes.

needed for the synthesis of the overall GAME objectives.

Another issue may be the interaction between theHere, I would like to briefly comment on some key is-cloud/precipitation system and the land surface condi-

sues for the synthesis of GAME.

tions, including topography and land use/land cover conditions. One important problem we have noticed may the

2. Large-scale land-atmosphere interaction and re-important role of water-fed rice paddy field, which is a

gional/continental-scale climate

typical land surface condition in monsoon Asia, in the

Energy and water cycle processes in various plot-scale

development and/or modifying the precipitation systems.

and meso-scale regions have been revealed in the diurnal

The observational as well as model-based evidences of

to seasonal time scales. In some areas, year-to-year vari-this aspect have been suggested in the tropical (GAME-

ability has also been obtained. An important issue, as a

Tropics) and sub-tropical (GAME-Hubex) region. The

next step, may be how to scale-up or integrate these sur-large-scale and regional-scale topography is also a key

face processes in a small area to larger-scale processes

factor controlling the precipitation system in the mon-in the atmosphere. The IOP of GAME-Siberia in thesoon region. The observational as well as modeling stud-spring/summer of 2000 conducted the aircraft measure-ies in the tropics (GAME-Tropics) and in the Tibetan Pla-ment of heat and CO2 fluxes over the meso-scale region

teau (GAME-Tibet) have presented some interesting pro-near Yakutsk. These data will help us to understand thecesses in the diurnal as well as in the synoptic-scale. The

time-space structure of the atmospheric boundary layer

regional model studies are essential for these problems,in terms of the land surface energy and water fluxes. The

including improvement of land-surface schemes and thecomparison and validation of surface fluxes in the mod-atmospheric boundary layer processes based on theels and observations are also being conducted, from the

GAME data sets.

viewpoint of scaling-up and down. In this respect, GAME
will contribute to modeling activity of the GEWEX At-

4. Key processes related to the interannual variabil-mospheric Boundary Layer Study (GABLS), which is aity of the Asian monsoon

new initiative of the GEWEX Modeling and Prediction

GAME has focused the interaction and feedback pro-

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22

May 2002

GAME Letter No. 4

cesses between land and atmosphere. In fact, the observa-

action with land surface processes. GAME modeling ac-

tional results of the regional experiments have revealed

tivity includes these processes using atmospheric GCMs

some important processes on the land-atmosphere inter-and coupled atmosphere-ocean GCMs. However, almost

action, including the roles of snow cover, soil moisture

all the current GCMs have very large systematic errors inand vegetation. For example, the regional and continen-

simulating the mean monsoon climate and circulation

tal-scale vegetation, such as tropical monsoon forest in(Kang et al., 2001). For example, the simulated monsoon

southeast Asia, and the boreal forest in east Siberia, haveprecipitation on land, particularly near the coast in south

been suggested to play an important role in controllingand southeast Asia tend to be far larger than the observa-

seasonal surface energy and water balance. This role oftion, whereas that over the warm pool region in the west-

vegetation, in turn, modifies the seasonal cycle of the cli-ern Pacific tend to be smaller compared to the observa-mate and atmospheric circulation. Some model experi-tion. These defects in GCMs both in the seasonal cycle

ments also have strongly suggested these processes.

and spatial distribution need to overcome by improving

GAME data sets include the full seasonal data of twoland-atmosphere as well as ocean-atmosphere processes.

or three years since 1997. Particularly, the data of 1998,

The forthcoming CEOP (Coordinated Enhanced Observ-

the IOP year, can be compared, in many aspects, with thoseing Period) under World Climate Research Programmeof 1999, when the secondary IOP was conducted in(WCRP) to be held in 2001 to 2003 will provide us a

GAME-Tropics and GAME-Hubex region. The anomalies

good opportunity for providing sufficient data for furtherof the overall monsoon circulation and precipitation be-

understanding the Asian monsoon with its interannual vari-

tween these two years are well contrastive, so that the in-ability.

ter-comparison of the processes related to the monsoon

References

activity in each region seems to be very beneficial for

GAME International Science Panel, 1998: GEWEX Asian Mon-

understanding the interannual variability of the Asian monsoon.
To fully understand the seasonal cycle and interannual
variation of the Asian monsoon, we need to include thesoon Experiment (GAME) Implementation Plan. pp. 136.
Kang, I.-S., et al., 2001: J. Climate, submitted.
Yasunari, T. et al., ed.,2001: Special issue, GEWEX Asian Monsoon Experiment (GAME), J. Meteor. Soc. Japan, 79B,
241-605.

large-scale atmosphere-ocean processes and their inter-

KEOP as a KORMEX Follow – on
Jai–Ho Oh and Baek-Jo Kim
Meteorological Research Institute, KMA ,Seoul , Korea
jho@metri.re.kr

Changma (rainy season in Korea) front. These weather
systems account for more than 70 percent of the natural
disasters over Korea. Needless to say that for better prediction 3–dimensional atmosphere / ocean / land intensive observations are needed. The sparse observational
network over the oceans causes low predictive skills of

The Korea Enhanced Observing Period ( KEOP ) fromthe mesoscale severe weather phenomena. Hence the main

January 2001 through December 2005 is planned undergoal of KEOP is to develop continuous 3–dimensional

the Korean Monsoon Experiment ( KORMEX )observational system based on remote meteorological

Programme. KORMEX was conducted in collaboration

monitoring network. This will result in generation of high–with the GEWEX Asia Monsoon Experiment (GAME),

resolution observational data needed for the initialization

the South China Sea Monsoon Experiment (SCSMEX),

of typhoon track prediction models.

and the Huaihe River Basin Experiment (HUBEX). The

Keeping the above in view intensive field–based ex-

prime scientific objective is to improve the skills in pre-periments will be implemented during the period for

diction of severe weather systems in summer such as ty-

2001-2003 consisting of the observational systems asphoons and heavy rainfall events associated with thefollows :AME

GAME Letter No. 4

23

May 2002

1) Short–term surface and upper–air observations during

the structure and intensity of typhoons, their track pre-IOP

diction, mesoscale and marine meteorological modelling.

- Aerosonde , Autosonde and Radiosonde Observations

All these efforts will need collaboration with international- Radar and/or Dual Doppler – Radar Observations

projects (e.g., CAMP, ARGO ) and co-operation with Ja-- Operational Satellite Observations

pan and China for data from their neighbourhood . It is- Drifting Buoy Observations

hoped that this programme will lead to improvement of2) Long–term monitoring

typhoon prediction (track and intensity) , improvement in- Radiation

long range prediction, better prediction capability of- Land – surface heat/water fluxes

Changma and lead to data exchange between CEOP and- Sea – surface heat/water fluxes

KEOP.

A KEOP Data Centre will be established with the main

Dr. Jai-Ho Oh, Dr. Won-Tae Kwon and Dr. Baek-Jo

aim of collecting, compiling, scrutinizing and managing

Kim are the Project Leader, Data Manager and the Secre-

the observational data collected. Besides the field–based

tary respectively of the KEOP Project. More details on

experiments and the KEOP Data Centre, this programme

this project are available on the website:

also envisages application studies such as investigating

http://www.metri.re.kr/monsoon/keop.html

Figure: An outline of the KEOP Project

AME

24

May 2002

The Sixth GAME International Science Panel
Meeting and
The Fifth International Study Conference on
GEWEX in Asia and GAME
Kenji Nakamura
Hydrospheric Atmospheric Research Center,
Nagoya University, JapanThe Sixth GAME International Science Panel meeting (GISP) was held at the Aichi Trade Center, Nagoya,Japan for 1 and 2 October, 2001 under the auspices of
Ministry of Education, Culture, Sports, Science and Technology (MEXT), World Climate Research Programme(WCRP), National Space Development Agency of Japan(NASDA), Center for Climate System Research (CCSR)
in the university of Tokyo, and Hydrospheric Atmospheric Research Center (HyARC) in Nagoya University.
Total 59 participants including observers/experts from
13 countries joined.
The main subject of this GISP was the future plan for
the GAME. According to the last (the fifth) GISP agreement that the GAME should continue for a few more years
to accomplish the GAME objectives after reviews of thecurrent GAME results, Dr. R. Lawford and Prof. T.-C.
Chen presented their reviews. Generally speaking theirreviews are very positive. They, however, pointed out that
we need more efforts on cross cutting issues and synthesis of data towards the monsoon system understanding.
According to the reviews, the GAME Phase-II was approved. (The current result reports appear in the GAME
Letters in No. 3 and this one)GAME Letter No. 4

To deal with the issues pointed out in the reviews, considering that (1) objective of GISP changes from coordination, implementation and data distribution policy, tosynthesis and analysis of data, data distribution, model
study for the original GAME objectives, and (2) someregional study groups have already accomplished the observations, re-organization of GISP was proposed. The
re-organization includes establishment of advisory board
and new working groups. The new working groups will
discuss Water and Energy Balance Study(WEBS; under
GHP), land surface processes/ABL/AAN, precipitation
processes, monsoon system study (analysis /diagnostic
study), monsoon system modeling, re-analysis, satellite
utilization, GAIN, GAME-Siberia, and Water Resources
Application Project(WRAP; under GHP). The new memberships include chairpersons of working groups and reduced number of country representatives with liaisons
to WCRP and CEOP. The proposal was adopted thoughdetails such as the number of membership were remained
to be determined.
The follow on of GAME was another issue. Coordinated Enhanced Observing Period (CEOP) was the focusof the discussion. Considering that CEOP is a big new
project, GISP agreed that CEOP or CEOP/CAMP international science panel should be separated from GISP.
Following the GISP meeting, the Fifth International
Study Conference on GEWEX in Asia and GAME washeld at the same location for 3-5 October, 2001. About
190 participants from 15 countries joined this conference. The presentations were oral and posters and three
volume proceedings were delivered at the conference.

GAME Letter
Published by the GAME International Project OfficeProf. Kenji Nakamura, Director
Editors: Dr. Atsushi Higuchi, Ms. Tomoko Tanaka, and Ms. Yuri Tanaka
Hydrospheric Atmospheric Research Center
Nagoya University
Furocho, Chikusaku, Nagoya 464-8601, Japan
Phone: +81-52-789-5439, Fax: +81-52-789-3436
E-mail: gio@ihas.nagoya-u.ac.jp, URL: http://www.ihas.nagoya-u.ac.jp/game/index.html