Annual Report

Hydrospheric Atmospheric Research Center(HyARC)
Nagoya University

2010

drospheric tmosphericesearch enter(HyARC)

2010
NAGOYA
UNIVERSITY

Contents
Foreword

2

Staff and Organization

3

Research Programme

6

Progress Reports

8
12
12
18
22
24
24
26
30
List of Publications 32
Projects

Division of Regional – Scale Water Cycle Processes
Laboratory of Meteorology

Laboratory for Climate System StudyLaboratory for Cloud and Precipitation Climatology

Division of Global – Scale Water Cycle Variations
Laboratory of Satellite Meteorology

Laboratory of Satellite Biological Oceanography
Laboratory of Bio-Physical Oceanography

2

Foreword
The Hydrospheric Atmospheric Research Center (HyARC) at Nagoya University
was established 10 years ago to promote research on the global water cycle, which isa primary component of the earth system. Research on the global water cycle requires
strong and extensive collaboration among science and application communities. Therefore, HyARC functions as an inter-university collaborative system, which is in many
ways unique in the world. In order to ensure the activity HyARC has been accredited
as a Joint Usage/Research Center since April 2010 by the Ministry of Education, Culture, Sports, Science and Technology, Japan.
HyARC has initiated numerous projects and activities. Prominent among these is
the International Project Office for the Global Energy and Water Cycle Experiment(GEWEX) Asian Monsoon Experiment (GAME) led by Prof. T. Yasunari, and its
various follow-on projects. Additional work has been supported by the following:
Grants-in-Aid for Scientific Research; Core Research for Evolutional Science andTechnology (CREST) of Japan Science and Technology Corporation (JST); Global
Environment Research Fund; Innovative Program of Climate Change Projection forthe 21st Century; and more. In addition, funding from the Ministry of Education,
Culture, Sports, Science and Technology, Japan, supported the construction of amultiparameter radar system to study water circulation, and funding from the InterUniversity Project supported a virtual laboratory for diagnosing the earth’s climate
system.
HyARC has also collaborated with numerous institutions such as Research Institute of Humanity and Nature (RIHN) and National Institute of Information andCommunication Technology (NICT). As partial contribution to the UNESCO International Hydrology Programme (IHP), HyARC has conducted training courses supported by the Japan Trust Fund. This year’s course was on satellite remote sensing
of atmospheric constituents.
While selecting projects and activities, HyARC considers project feasibility, significance, and collaboration requirements. It currently funds three research projects
and four workshops. Although HyARC has only 10 permanent staff members (fourprofessors, three associate professors, and three assistant professors), it supports
many postdoctoral candidates in active research. In addition, HyARC has accepted
graduate students in the Department of Environmental Studies.
Nagoya University has adopted a flexible management system that emphasizes
accountability, yet encourages research publications and outreach programs. With
the encouragement provided by an external evaluation committee, we herewith propose to establish a large-scale national/international facility and a new organization
for addressing its social requirements.

Uyeda Hiroshi
Director
Hydrospheric Atmospheric Research Center3

Staff and Organization
Research
Division
Board ofCouncilors

Director

Division of Regional – Scale Water Cycle Processes
Professor

UYEDA Hiroshi

YASUNARI Tetsuzo

Assoc. Professor

TSUBOKI Kazuhisa

MASUNAGA Hirohiko

Assist. Professor

SHINODA Taro

FUJINAMI Hatsuki

VL Promotion Unit
Advisory
Board
Board onResearch
Collaboration

Designated
Assist. Professor

OHIGASHI Tadayasu

Division of Global – Scale Water Cycle Variations
Professor

NAKAMURA Kenji

Assoc. Professor

MORIMOTO Akihiko

Assist. Professor

MINO Yoshihisa

Designated
Assist. Professor

TANAKA Hiroki

Technical Office (Technical Center)
Secretary OfficeMINDA Haruya
IWAMOTO Keiko

Administrative Office
Administrative TANIGUCHI Tetsuya
Director
Administrative SUGIE Osamu
Vice-Director
General Affairs Section
Accounting Section
Research Promotion
Section
Supplies Section
Student Affairs Section

ISHIZAKA Joji

4
Administration
Board of Councilors
UYEDA Hiroshi: Director, Prof., Hydrospheric Atmospheric Research Center, Nagoya University
NAKAMURA Kenji: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
YASUNARI Tetsuzo: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
ISHIZAKA Joji: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
TANAKA Kentaro: Prof., Graduate School of Science, Nagoya University
TSUJIMOTO Tetsuro: Prof., Graduate School of Engineering, Nagoya University
TAKENAKA Chisato: Prof., Graduate School of Bioagricultural Sciences, Nagoya University
KANZAWA Hiroshi: Prof., Graduate School of Environmental Studies, Nagoya University
MATSUMI Yutaka: Prof., Solar-Terrestrial Environment Laboratory, Nagoya University

Advisory Boardl Members from Nagoya Unisversity

NAKAMURA Kenji: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
YASUNARI Tetsuzo: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
ISHIZAKA Joji: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
TSUBOKI Kazuhisa: Assoc. Prof., Hydrospheric Atmospheric Research Center,
Nagoya University
MASUNAGA Hirohiko: Assoc. Prof., Hydrospheric Atmospheric Research Center,
Nagoya University
MORIMOTO Akihiko:

Assoc. Prof., Hydrospheric Atmospheric Research Center,
Nagoya University

l Members outside Nagoya University

FUJIYOSHI Yasushi: Prof., Institute of Low Temperature Science, Hokkaido University
HANAWA Kimio: Prof., Graduate School of Science, Tohoku University
SUMI Akimasa: Prof., Integrated Research System for Sustainability Science,		

The University of Tokyo

FUKUSHIMA Yoshihiro: Designated Prof., Tottori University of Environmental Studies
YAMANAKA Manabu: Principal Scientist, Research Institute for Global Change, Japan
Agency for Marine-Earth Science and Technology
YAMANOUCHI Takashi: Prof., National Institute of Polar Research
TANIGUCHI Makoto: Prof., Research Institute for Humanityand Nature
OKI Riko: Senior Researcher, Earth Observation Research Center, Japan Aerospace
Exploration Agency

5
Board on Research Collaborationl Members from Nagoya University

NAKAMURA Kenji: Prof., Hydrospheric Atmospheric Research Center, Nagoya
University
ISHIZAKA Joji: Prof., Hydrospheric Atmospheric Research Center, Nagoya University
MORIMOTO Akihiko: Assoc. Prof., Hydrospheric Atmospheric Research Center,
Nagoya University
l Members outside Nagoya University

FUJIYOSHI Yasushi: Prof., Institute of Low Temperature Science, Hokkaido
University
YAMANAKA Manabu: Principal Scientist, Research Institute for Global Change,
Japan Agency for Marine-Earth Science and Technology
TANIGUCHI Makoto: Prof., Research Institute for Humanityand Nature
OKI Riko: Senior Researcher, Earth Observation Research Center, Japan Aerospace
Exploration Agency

6 Research Programme
Water circulation studies using new polarimetric radars
In 2007, new polarimetric (multiparameter) radars were installed at the Hydrospheric
Atmospheric Research Center (HyARC), Nagoya University. Since its installation, this equipment has been promoting new studies on clouds and precipitation, thus aiding in the development of new observational and analytical techniques that are essential for studies on water
circulation. Such observational and analytical techniques as well as data assimilation methods
are necessary for utilizing observational data from the new radars and for amalgamating thedata with a cloud-resolving model.
This research program aims at promoting research on water circulation using the newpolarimetric radars and existing radar sets. In particular, we examine and implement observational data of weather phenomena and physical processes of cloud and precipitation systems.
We aim at developing new parameters for multiparameter radar observations and data analysis and new display methods for radar data. We will develop software and operational routines
for the radar equipment from physical and engineering viewpoints in collaboration with researchers participating in this study project.

Diurnal processes of convection/precipitation systems in the climate
SystemDiurnal variation in convection and precipitation is a prominent meteorological feature,
particularly in the tropics/subtropics and monsoon regions. Energy, water, and momentum
exchanges through the diurnal cycle between the earth surface, atmospheric boundary layer,
and free atmosphere play a crucial role in global climate models (GCMs) and still cannot
reproduce a realistic diurnal cycle in convection/precipitation, including systematic errors in
the models.
This research plan aims to clarify the regionality and seasonality of diurnal processes
based on TRMM, other remote sensing data, and in-situ observational data from rain gauge
stations. Cloud resolving models (e.g., CReSS and WRF) and other regional models are also
used to elucidate systematic errors in the climate model due to the diurnal cycle. These studies can contribute to the ongoing international project “MAHASRI.” We aim to promote studies on the diurnal process of convection/precipitation in the climate system in Japan.
On December 19, 2007, a domestic workshop, co-hosted by MAHASRI, was held in Hakone.
Studies on the diurnal variation of cloud/precipitation systems, including the relationshipwith terrain, synoptic conditions and intraseasonal variation, were presented. These studies
covered areas from the Tibetan Plateau to the Maritime continents. In total, 14 participantspresented new scientific results and there was a lively discussion with many participants inthe workshop. Future issues on diurnal cycles were also discussed.

7
Study of atmospheric and oceanic climates over Okinawa Island and its
surroundings
The Okinawa Subtropical Environment Remote-Sensing Center, an observation facility
in Okinawa, Japan, was established by the The National Institute of Information and Communication Technology (NICT). These facilities offer the use of full polarimetric Doppler
radar (COBRA), 400 MHz wind profiler radar, Doppler sodar, disdrometers, rain gauges, andocean radars. In 2005, an interuniversity collaboration was formed between NICT, Okinawa,
and the Hydrospheric Atmospheric Research Center at Nagoya University, Japan (HyARC).
Several interesting phenomena, such as a cold water appearance in northern Taiwan aftera typhoon, have been reported. New observations, such as a dual-Ka radar system observation, have also been introduced. The direction of the next step was discussed, and two directions have been identified: (a) flexible ocean radar development and applications and (b)Ka-band radar observation with a versatile C-band Doppler radar.
The scientific objectives are not always concrete; however, the technology to remotely
observe atmospheric and oceanic phenomena is similar. NICT develops radiowaves sensors,and HyARC organizes the exploration of deeper and wider applications. The importance ofthe collaboration is well recognized.

8Progress Reports
Projects
Formation of a virtual laboratory for diagnosing the earth’s climate system (VL)
To conduct collaborative research and provide education in addressing high-stress factors
such as global warming, a virtual laboratory for diagnosing the Earth’s climate system (VL)
was formed in 2007 by four university research centers studying climate and environment.
HyARC set up the Atmospheric Research Promotion Team (VL Promotion Team) to progress
the collaborative research. We focus our studies on water budgets associated with clouds andprecipitation and develop an observation and analysis system. We analyze two polarimetric
Doppler radar data to diagnose a category of hydrometeor particles, develop a cloud-resolving
model known as Cloud Resolving Storm Simulator (CReSS), validate its results using a satellite simulator known as Satellite Data Simulation Unit (SDSU), and establish a data assimilation method for a mesoscale precipitation system.
In 2010, we performed continuous observation with a polarimetric Doppler radar locatedat Nagoya University. A heavy rainfall event occurred in the southeastern region of Gifu Prefecture on July 15, 2010. The structure of the precipitation system was clarified using thepolarimetric radar and was accurately reproduced using CReSS. In addition, the lightning
frequency was reproduced using CReSS Lightning Simulator. Moreover, we used polarimetricradar data to conduct statistical analysis of precipitation cells over the Nobi Plain.
We compared brightness temperatures (TBBs) of infrared and microwave bands obtained
from satellite observations with those calculated by SDSU applied to the daily simulation
results using CReSS. Satellite data were provided by Center for Environmental Remote Sensing (CEReS), Chiba University, under the framework of VL. Figure shows horizontal distributions of TBB for infrared band obtained by satellite observation and simulation over the Taiwan–Okinawa region. Two well-developed Mesoscale Convective Systems (MCSs) with minimum TBB less than 200 K developed over the southeast and southwest areas far from Taiwan
Island in satellite observation. The southeastern MCS can be reproduced in the simulation.
We will confirm biases and improve the accuracy of the microphysical processes of CReSS in
comparison simulation results with satellite observations statistically,.

Fig. Horizontal distributions of TBB for the infrared band obtained by satellite observation (MTSAT-CH1: left) andsimulation (CReSS-SDSU: right) at 17 UTC on May 29, 2010 over the Taiwan–Okinawa region.

9
The Innovative Program of Climate Change Projection for the 21st Century (KAKUSHIN Program)l Cloud Modeling and Typhoon Research

Cloud physics is one of the key processes for modeling climate change, especially for
global warming. Improving cloud processes is essential for accurate simulations. Cloud processes are also core processes in simulations of high-impact weather systems such as heavy
rainfalls and typhoons. The cloud modeling team has been developing a cloud-resolving model called the Cloud Resolving Storm Simulator (CReSS). The cloud microphysics and computation scheme of CReSS are improved for accurate and high-speed calculation. Convective
clouds in the tropical region and typhoons are important objects of our team. The CReSS
model is also coupled with global models to simulate convective regions. CReSS is used for
typhoon research, which aims to help verify typhoon simulations made by global models andto produce accurate and quantitative evaluations of typhoon effects on human society under
the present and future climates.
Occasionally, typhoons cause severe disasters owing to heavy rainfall and strong winds.
On the other hand, they bring a large amount of water to the East Asian countries. Changes
in typhoons with global warming, therefore, have a large impact on human society. Because
typhoons are composed of intense convective clouds and associated stratiform clouds, a cloudresolving simulation is necessary to accurately predict their intensity. In the present study, we
have developed a new technique for performing a parallel computation of the cloud-resolving
model in an arbitrary-shaped region, which is named the “Tiling Domain Technique” forCReSS. The figure shows a three-dimensional display of simulated clouds associated with thetyphoon over Taiwan in 2009. The eyewall around the eye is located over Taiwan. The cloudband to the south of the eye caused heavy rainfall in southern Taiwan. The simulation showsthat the cloud-resolving simulation enables us to quantitatively predict the typhoon intensity.
By collaborating with the other team of the KAKUSHIN program, our team performed simulation experiments of typhoons in the global warming climate and found that extremely intense
typhoons, which have never occurred in the present climate, will occur in the future climates.

Fig. Three-dimensional display of simulated typhoon No.8 in 2009 using POV-Ray. The whiteshading shows the mixing ratio of cloud water at 02 UTC August 8, 2009.

10
Study consortium for Earth-Life Interactive System (SELIS)The Study consortiumu for Earth-Life Interactive System(SELIS) was established as a
virtual institute in Nagoya University in March 2008, to follow up the research activity of the
21st century COE Program of  “the Sun-Earth-Life Interactive System”. The member instateof SELIS are HyARC, Graduate School of Environmental Sciences (GSES), Graduate Schoolof Bio-Agricultural Sciences (GSBS) and the Solar-Terrestrial Environmental Laboratory. The
SELIS project office is located at the 5th floor of the Institute for Advanced Research Hall of
this campus, and the HyARC is managing this office as a main institute of SELIS. The main
objective of the SELIS is to promote coopearative studies and relevant capacity building for
the Earth-Life Interaction studies, and to promote collaboration with relevant national andinternational programs and projects. SELIS is also expected to contribute to research projects
proposed from Nagoya University to the Research Institute for Humanity and Nature (RIHN)
in Kyoto. In the education program, SELIS contributes to some lecture course and seminars,
e.g., “Chikyu-gaku” (Study for the Earth) at the GSES.
In academic year 2010, SELIS organized seven interdisciplinary seminars. SELIS also
contributes to basic environmental studies and education under the Global COE Program“From Earth System Science to Basic and Clinical Environmental Studies (BCES)” that started in July 2009.  In November, SELIS co-sponsored an international workshop on “Impact ofsolar activity on climate variability and change”.   Two faculty members of SELIS, with a
graduate student, published one scientific paper (Zhang, Yasunari and Ohta, 2011) on the
Taiga-parmafrost coupled system in Siberia and its response to the future climate change at
the Environmental Research Letters (ERL), which is an internationally-renowned journal on
the environmental sciences.

11

12 Division of Regional – Scale Water Cycle Processes
Laboratory of Meteorology
Maintenance and enhancement mechanisms of the precipitation band formed along the Ibuki–
Suzuka Mountains on September 2–3, 2008
A heavy precipitation event occurred along the Ibuki–Suzuka Mountains located in thewest of the Nobi Plain, Japan on September 2–3, 2008. The maximum total precipitation
amount observed by rain gauges for 18 h was 425 mm. This event was caused by a stationary
precipitation band that formed along the north–south-oriented mountains and stagnated forapproximately 13 h from 12 JST on September 2 to 01 JST on September 3. The length andwidth of the band were approximately 100 km and 20 km, respectively.
A time series of horizontal winds in a verticalprofile observed by a wind profiler radar located at
Nagoya Local Meteorological Observatory shownin Fig. 1 was captured on the windward side of theband. The low-level southeasterly wind was warm
and moist with equivalent potential temperature
greater than 355 K and was induced by a synoptic
condition (not shown). It would impinge on theeastern slope of the Mountains and continuously
develop precipitation cells. These cells were propagated northward by southerly winds above a heightof 1 km (Fig. 1), corresponding to the alignment of Fig. 1 Time series of horizontal winds in a vertical profile observed from 00 JST on September 2 to 06
the band. The maintenance of the band would be
JST on September 3, 2008 by a wind profiler radar
attributed to keep the vertical wind profile for aplocated at Nagoya Local Meteorological Observaproximately 13 h through the synoptic condition.
tory. Full and half barbs depict 5 and 2.5 m s–1,
respectively.
Two significant heavy precipitation areas withhorizontal scales of approximately 10 km appeared in the band. One of the areas was includedin the range of a dual-Doppler analysis obtained by two X-band polarimetric Doppler radars.
This analysis show that a low-level southeasterly wind at a height of 1 km converged in a wedgeshaped valley opening southward between the Ibuki-Suzuka Mountains and its branch, the Yoro
Mountains, which are oriented north–northwest to south–southeast (Fig. 2). The location of thisvalley corresponds to the windward direction of warm and moist inflow. The precipitation enhancement mechanism of this area can be attributed to the continuous updrafts and development of precipitation cells formed by the low-level convergence over this valley.

Fig. 2 (a) Horizontal distribution of reflectivity at a height of 3 km (shades) and horizontal winds at 1 km (arrows) at 1730 JST
on September 2, 2008. Contour shows a height of 300 m above sea level.
(b) Vertical cross section of reflectivity (shades) and wind vectors along the A–B plane (arrows) in (a).

13Structure and formation mechanism of the rainband around the center of Typhoon 0918 at landfall
Heavy rainfall produced by landfalling typhoons
interacted with the typhoon’s atmospheric environment, underlying surface condition, and internal mesoscale structure. Although many previous studies havereported the orographic effect on the heavy rainfall
produced by landfalling typhoons, additional factors
have not been studied much. Typhoon 0918 (T0918)
brought heavy rainfall to the Kii Peninsula and Aichi
Prefecture from 00 to 07 JST on October 8, 2009. The
purpose of this study is to clarify the structure andformation mechanism of the rainband around the center of T0918 at landfall and structure alteration to an
extratropical cyclone.
The heavy rainfall area proceeded northward overthe eastern slope of the Kii Peninsula with the propagation of T0918 from 00 to 04 JST on October 8. Strong
easterly winds in the lower troposphere were observedin the northern side of the typhoon center during theperiod. Equivalent potential temperature in the lowlevel easterly wind was greater than 350 K, thus a warm
and moist airmass ascended over the eastern slope of
the Kii Peninsula and brought heavy rainfall. During
the period, the observed cloud-top height was not significantly high, and lightning was not observed throughLightning Location System (LLS) operated by Chubu
Electric Power Co., Inc. The fact that the heavy rainfall Fig. 3 Horizontal distribution of reflectivity at a heightof 2 km observed at 0442 JST on October 8,
was caused by the relatively shallow precipitation sys2009 by an X-band polarimetric radar locatedtem over the Kii Peninsula corresponds to several preat Anjyo City (upper) and vertical cross sectionof reflectivity along the A–B line at the same time
vious studies.
(lower).
As T0918 propagated northward, heavy rainfall wasobserved near Aichi Prefecture. The heavy rainfall was caused by a rainband aligned from south–
southwest to north–northeast whose echo-top height defined by 20 dBZe was higher than 12 km(Fig. 3). Frequent lightning was also observed by LLS during the passage of the rainband near
Aichi Prefecture. Figure 4 shows horizontal distributions of reflectivity at heights of 2 km and 7
km at 0350, 0410, and 0450 JST on October 8 observed by the Doppler radar located at Nagoya
Local Meteorological Observatory. The deep rainband observed at 0450 JST developed throughthe merging of a shallow precipitation region that formed near the eastern coast of
the Shima Peninsula into another shallow
precipitation region that propagated over
the Kii Peninsula. This rainband proceeded
northeastward and was maintained by convergence of a low-level warm and moist
southeasterly wind in the eastern side anda relatively low equivalent potential temperature airmass with the northwesterly
wind in the western side. Therefore, thestructure of the deep rainband differedfrom that of the shallow precipitation region that developed over the eastern slope
Fig. 4 Horizontal distributions of reflectivity at heights of 2 km (upper)of the Kii Peninsula. The deep rainband
and 7 km (lower) at 0350 (left), 0410 (center), and 0450 (right)
JST on October 8, 2009 observed by the Doppler radar located was formed abruptly by the merging of two
shallow precipitation regions.
at Nagoya Local Meteorological Observatory.

14
Relationship of polarimetric parameters with properties of solid precipitation particles observedin the Hokuriku district, Japan during the winter season in 2008–2009
To understand the characteristics of solid precipitation particles using polarimetric radars, it
is first necessary to clarify the relationship between the properties of these particles and polarimetric parameters. The purpose of this study is to examine the relationship of polarimetricparameters obtained by a radar and properties of solid precipitation particles (category, diameter,
shape, and number concentration) observed by a ground-based particle-imaging system atKanazawa University during the winter season in 2008–2009.
The polarimetric radar located at Oshimizu, Ishikawa Prefecture, Japan yielded parametersof radar reflectivity (Zh), differential reflectivity (Zdr), specific differential phase (Kdp), and correlation coefficient between horizontal and vertical polarization signals (ρhv). The ground-based
particle-imaging system at Kanazawa University located approximately 30 km from the radar
recorded photographs of each solid particle and digitized it by an image-processing technique toachieve the shape and diameter of each particle and their number concentrations. The complexity, which is the ratio of the circumference length to that of the minimum area, and number ofholes were used to determine classification of particle into snowflake or graupel. Here, particles
without holes and with complexity less than 1.21 are defined as graupel, while remaining particles
are defined as snowflakes. Moreover, particle with diameters less than 3 mm were excluded fromthe analyses because their size made examination impractical. The total volume of snowflake andgraupel particles was calculated as the sum of particle volumes achieved by rotating particle area.
Category and typical characteristics of predominant particles were determined in 1-min intervals.
To match the target area between the volumes obtained by both methods, the target volume on
the radar bin in the lowermost Plan Position Indicator (PPI) scan was prescribed through consideration of category, fall velocity, and horizontal wind direction and speed.
Our observation periods were 1900–2100 JST on Jan 13, 1255–1500 JST on Jan 15, and 2100–
2130 JST on Feb 16, 2009. Figure 5 shows a time series of polarimetric parameters, number, andvolume of each category from 1255 to 1500 JST on Jan 15. When conical or round graupel particles
with diameters from 3 to 6 mm (graupel period) were predominantly observed, Zh, Zdr, Kdp, andrhv ranged from 19.9 to 31.2 dBZe, -0.6 to -0.1 dB, −0.3 to −0.1°/km, and 0.99 to 1.00, respectively.
When snowflakes with diameters from 6 to 15 mm (snow period) were predominantly observed,
the same parameters ranged from 14.9 to 27.2 dBZe, −0.5 to −0.2 dB, −0.2 to 0.3°/km, and 0.99 to
1.00, respectively. During the
graupel period, Zh increased incorrelation with the same shift inobserved particle diameters or
number concentrations. In addition, Zdr decreased (approached 0dB) when the predominant particle shape was conical (round).
These results correspond to thoseshown in previous studies. The
lower threshold of Zh to detect
graupel should be reconsidered
because the minimum Zh was approximately 20 dBZe in this study.
It is interesting to note that during Fig. 5 Time series of polarimetric parameters (upper and middle panels), number,the snow period, Zdr and Kdp valand total volume of snow/graupel particles (lower panel) observed from1255 to 1500 JST on January 15, 2009. Zh (solid line) and Zdr (broken line)
ues were close to zero, which ilobtained by a polarimetric radar in 5-min intervals are shown in the upper
lustrates that snowflake shapes
panel. Kdp (broken line) and ρ hv (solid line) are shown in the middle panel.
Number of snow particles (orange bar graph), graupel particles (blue bar
should not be oblate; that is, thegraph), and volume of snow (broken line) and graupel (solid line) obtained
vertical and horizontal diametersby the ground-based particle-imaging system at every 1-min intervals areshown in the lower panel.
match.

15
Vertical observation of ice particle size distributions in a stratiform region of a Mesoscale Convective System during the Baiu period
Although many previous studies documented the dynamic structure of Mesoscale Convective Systems (MCSs), no research is based on microphysical in situ
observation of ice particles with diameters less than 500 µm. We conducted anin site observation of ice particles in a
stratiform region of a MCS on June 12,2008 using hydrometeor videosonde(HYVIS) at Okinawa Island. This study
analyzes the vertical distribution of ice
particle properties obtained by HYVIS
observation, including shape, number
concentration, and particle size distribuFig. 6 Vertical profiles of number concentrations of each categorytions (PSDs), and discusses the ice
divided by their shape (shaded bar graph), which was delimited by a maximum diameter of 100 µm. Maximum particle
particle growing process.
diameterless than 100 µm (left) and greater than or equal to
A MCS focused in the present study
100 µm (right) are shown. Solid and broken lines represent
developed along the Baiu front and propthe degrees of ice and water of saturation, respectively.
agated eastward over the East China Sea.
Its stratiform region covered Okinawa Island. HYVIS launched at 1426 JST on June 12 shows
the melting level at a height of 4.5 km. Using images obtained by HYVIS, ice particles wereclassified into six categories according to their shape: needle, column, plate, column and plate,aggregate, and undefined. The vertical profiles of number concentrations of each category
and PSDs were also estimated.
Figure 6 shows vertical profiles of number concentrations of each category divided bytheir shape, which was delimited by a maximum diameter of 100 µm. The largest category
was the plate type, which suggested that the ice particles were obtained in low supersaturation conditions with ice less than 10%. The orders of number concentration with diameters
smaller or larger than 100 µm were 105 m−3 or 104 m−3, respectively. Almost undefined category was the small particles with diameters ranging from 10 to 20 µm. No supercooled liquid
particles or rimed ice particles were detected by HYVIS.
PSD is defined by slope parameter (Λ) and intercept parameter (N0). PSDs at each height
were calculated by fitting on the regression curve of the Marshall–Palmer distribution. Figure
7 shows vertical profiles of Λ and N0 calculated using PSDs at each height. The growth processof ice particles is assumed by the verticalprofiles of these parameters. When theheight decreases between 10 and 12 km,
between 7 and 8 km, and less than 6 km,
both Λ and N0 decrease. The variations ofthese parameters show a decrease in thenumber concentration of ice particles andthe appearance of large particles with adecrease in height, which suggests that
aggregation growth is predominant. On
the contrary, when the height decreases
between 8 and 10 km and between 6 and
7 km, Λ is constant and N0 increases, Fig. 7 Vertical profiles of N0 (left) and Λ (right) from the melting
level at approximately 4.5 km to 12 km. These parameterswhich suggests a predominant deposiwere obtained by fitting on the regression curves of the
Marshall-Palmer distribution.
tional growth.

16
Characteristics of precipitation cells observed by R/V Mirai over the tropical western Pacific
Ocean
Precipitation cells, which are fundamental elements of precipitation systems, require
statistical analyses to clarify their general features. This study investigates statistical characteristics of precipitation cells over the tropical western Pacific Ocean using data recorded
from June 6 to June 27 by a ship-borne Doppler radar and upper-air sounding observations
obtained by R/V Mirai (MR08-02) of Japan Agency for Marine-Earth Science and Technology(JAMSTEC) at 135.0E/12.0N. The area and 30-dBZe echo-top height of each precipitation cellwere analyzed as their horizontal and vertical scales, respectively. A three-dimensional detection algorithm developed in a previous study detected 13, 654 precipitation cells during theobservation period.
Figure 8 shows an integrated probability density of 30-dBZe precipitation cell echo-top
height. The ratio of the echo-top height not exceeding the melting level (4.9 km) + 1 km was
84%. The frequency of precipitation cells with echo tops higher than 8 km was substantiallylower, which is consistent with the characteristics of oceanic cells reported in previous studies. Figure 9 shows the probability density of an area of precipitation cells at a height of 2 kmwith an average and maximum frequency of 34.8 km2 and 21 km2, respectively, which indicatesthat the largest area is smaller than the average.
Upper-air sounding observations conducted every 3 h during stationary observation on
R/V Mirai show a change in the atmospheric environment; that is, mid-level dryness with a
low-level easterly wind was characterized in the former period, and a deep, moist layer witha low-level westerly wind developed in the latter. Sensitivity of the characteristics of precipitation cells on relative humidity (RH) at heights of 3, 4, and 5 km; vertical gradient of equivalent potential temperature between 0.5 and 6.0 km; and convective available potential energy (CAPE) as indices of atmospheric environments were examined. Precipitation cells havelower (higher) 30-dBZe echo-top height and smaller (larger) area at a height of 2 km in thelower (higher) RH at a height of 3 km. In addition, those with smaller (larger) area at a heightof 2 km correspond to the atmospheric environment with lower (higher) RH at heights of 4
and 5 km and with steep (gentle) vertical gradient of equivalent potential temperature. However, less sensitivity was observed on 30-dBZe echo-top heights in RH at heights of 4 and 5
km and vertical gradients of equivalent potential temperature. Moreover, less sensitivity inprecipitation cells was observed for CAPE characteristics.

Fig. 8 Integrated probability density of 30 dBZe echo-top
height in precipitation cells obtained by a ship-borne
Doppler radar on R/V Mirai (MR08-02).

Fig. 9 Probability density of area of precipitation cells
at a height of 2 km.

17Simulation of lightning activity using CReSS Lightning Simulator
We simulated lightning activity using a Lightning Simulator based on Cloud Resolving
Storm Simulator (CReSS). This Lightning Simulator features two processes: accumulationof electric charge by hydrometeor particle charging and lightning discharge. The lightning
discharge process includes the extension of lightning channels and charge neutralization.
Although the parameter sensitivity was confirmed in previous studies of the lightning channel
extension process, uncertainties existed for parameters of the charge neutralization process.
In the charge neutralization process, three parameters are used to conduct the sensitivity
experiment: minimum threshold of charge density that determines the region of charge neutralization (rchan); minimum threshold of charge density that remains behind charge neutralization (rneut); and ratio of neutralization (fr). If the charge density at a certain grid (Qx) is
greater than rchan, the grid has a possibility to be in lightning channels and neutralize. Here,the neutralized charge density in the grid is (Qx -rneut) × fr. This study examines sensitivity
experiments on the three parameters in the charge neutralization process by comparing frequencies of cloud-to-ground lightning and its polarity using LLS.
Figure 10 shows the ratio of negative polarity cloud-to-ground lightning to all cloud-toground lightning from 2340 to 2350 JST on September 2, 2008. Here, sensitivity with varying
fr and rchan are confirmed with constant rneut. Almost simulated polarities ratio in these sensitivity experiments corresponded to the observed one obtained by LLS; that is, negative
polarity was approximately 74%. This result suggests that fr and rchan have less sensitivity on
the polarity of cloud-to-ground lightning.
An additional sensitivity experiment revealed that high fr significantly decreased the frequency of the cloud-to-ground lightning, although less sensitivity for cloud-to-ground lightning
frequency was obtained by varying rchan and rneut. Moreover, less sensitivity was observed in
the ratio of the cloud-to-ground lightning to all lightning including in-cloud lightning by varying the three parameters, which suggests that the charge neutralization process is not significantly critical for lightning simulation. Thus, we can confirm that it is crucial for theLightning Simulator to reproduce thunderstorm development and their electric charge accumulation process.

Fig. 10 Simulated ratio of negative polarity cloud-to-ground lightning to all cloudto-ground lightning from 2340 to 2350 JST on September 2, 2008.
Parameters fr (horizontal axis) and rchan (type of line) are varied with constantrneut. Observed ratio of negative polarity by LLS is approximately 74%
indicated by the bold line.

18
Laboratory for Climate System Study
Dynamics of Larch Taiga–Permafrost Coupled System in Siberia under Climate Change
Larch taiga, also known as the Siberian boreal forest, plays an important role in global
and regional water–energy–carbon (WEC) cycles and in the climate system. Recent in situ
observations have suggested that larch-dominated taiga together with permafrost behave asa coupled eco-climate system across the broad boreal zone of Siberia. However, neither fieldbased observations nor modeling experiments have clarified the synthesized dynamics of thissystem. Here, using a new dynamic vegetation model coupled with a permafrost model, we
reveal the interactive processes between taiga and permafrost. The model demonstrates that
under the present climate conditions in eastern Siberia, larch trees maintain permafrost bycontrolling its seasonal thawing, which in turn maintains the taiga by providing sufficientwater to larch trees. The experiment without permafrost processes showed that larch trees
can decrease its biomass and be replaced by a prevalence of pine and other species that are
exposed to drier hydro-climatic conditions. In the coupled system, fire, although usuallydestructive, can preserve the larch domination in the forests. Climate-warming sensitivity
experiments show that this coupled system cannot be maintained if the temperature rises
above 2°C. Under these conditions, a forest with typical deciduous and dark conifer boreal
tree species would be alternatively dominated and decoupled from the permafrost processes.
This study thus suggests that future global warming could dramatically alter the larchdominated taiga–permafrost coupled system in Siberia through associated changes in WEC
cycles and feedback to climate.

Fig. 1 Schematic diagram of soil, vegetation, and fire feedback in the Siberian taiga–permafrost system consideredin this study (right-side diagram); spatial distribution of larch taiga (bottom left) and boundary of permafrost(bottom left, dashed lines); location (bottom left star) and climate of Yakutsk (top left). In the schematic diagram, arrows show force directions between each factor. Symbols “+” and “–” indicate a positive andnegative correlation between two factors, repectively; “±” indicates an unclear correlation. The thicker arrows indicate processes that were better considered in model simulation. Dashed arrow indicates a process
not considered in this study. The words beside each arrow identify the variables that control each process.

19
Reference:
Zhang, N.-N., , T. Yasunari and T. Ohta. 2011: Dynamics of the larch taiga-permafrost coupled system
in Siberia under climate change, Environ. Res. Lett. 6, 2, doi: 10.1088/1748-9326/6/2/024003

Fig. 2 Time sequence of simulated forest succession and active layer thickness (ALT) of permafrost. Colored areas
indicate the assembled simulation of above-ground forest succession from bare ground (first 300 years of
1000-year run); dashed line represents assembled result of simulated annual maximum ALT’ “+” symbols
indicate observed biomass above ground at different forest stages; pie charts show observed (left) andsimulated (right) forest compositions.

Fig. 3 Above-ground total biomass including fractional components of major species for CNTL run (left bar) andNP run (right bar) simulated under five various climate conditions. The five bar groups, from left to right,
represent the present climate conditions; temperature conditions of 1.12°C above the present; +2.25°C,+4.5°C, and +4.5°C plus precipitation of 20% above the present. The experiment names are shown above
each bar. The two dashed lines in the upper part of the figure show changes in summer (JJA) mean soil
water for CNTL and NP runs indicated by square and diamond marks, respectively. Note the changes ofmajor species contributing to the total biomass under the various climate conditions.

20
Long-term variability of Asian summer monsoon and its seasonality
Anthropogenic climate change due to increase in greenhouse gases and aerosol has becomea major issue in recent decades. Assessment of such climate change based on observational
data and sensitivity experiments with climate models is strongly required for better understanding of its process and mechanism. In this study, we have investigated the long-term
trends of the Asian summer monsoon rainfall and the circulation field during 1979–2008 on
a monthly mean basis by using the rainfall dataset (CMAP), reanalysis wind circulation data
(NCEP/NCAR), HadISST (UK Met office), and interpolated OLR data (NOAA). The non-parametric Mann–Kendall test is applied for evaluating the trends. In particular, we focused on
the seasonal dependence of long-term climate change.
In May, a significant increasing trend of monsoon rainfall is observed over the ArabianSea, the Bay of Bengal, and the South China Sea (Fig. 4a). Trends of strong westerly windappear along 10N, which correspond to enhanced convection with rainfall. In contrast, therainfall over the abovementioned areas shows a significant decreasing trend in June (Fig. 4b).
The increasing trend over Southern China is also remarkable in June. These rainfall trends
are consistent with the monsoon circulation and water vapor flux trends in the lower troposphere. In addition, we examined the variability in monsoon onset during 1979–2008 on thebasis of the climatological pentad mean rainfall data. The monsoon onset date defined by
Wang and LinHo (2002) is followed. In recent decades, the monsoon onset dates for southeastern and eastern Asia has been shifted approximately to 10–15 days early (Fig. 5), whichreflects the rainfall trends in May and June. Interestingly, the Asian monsoon rainfall in Julyand August does not have any clear significant trend. Thus, the Asian monsoon has a significant trend only during the transient phase from boreal spring to summer.
(a)

(b)

Fig. 4 (a) Linear trend of rainfall (CMAP; Shading: mm/day) and 850 hPa wind (NCEP/NCAR Reanalysis;
vector: m/s) in May during 1979–2008. All values are multiplied by 30 (years) for the period
1979–2008. Only those that are significant at 95% level by the Mann–kendall test are plotted.
(b) Same as the Left panel, but for June.

21
It is suggested that these trends of early monsoon onset are closely related to the increasing trends of SST over the tropical Pacific and Indian Ocean as well as the increasing trendsof the land surface temperature in the Asian continent. However, these SST warming trends
last throughout the year with less significant seasonal variations. GCM simulations suggest
strong seasonality in the effect of increase in anthropogenic or natural aerosol forcing on the
Asian monsoon climate.
This study is partially supported by the research fund for global warming under the Ministryof Environment (A0902) titled “Integrated Impact of Vegetation and Aerosol Changes on Asian
Monsoon Climate.”

Fig. 5 Date of monsoon onset obtained by climatological pentad mean rainfall during 1979–1993 (Digit). The
onset pentad is determined as in Wang and Linho (2002). The Julian pentad in which the relative rainfall
rate subtracted by the January mean exceeds 5 mm/day is defined as the onset pentad. Shading denotes thedifference between the monsoon onset for 1994–2008 and 1979–1993.

22
Laboratory for Cloud and Precipitation Climatology
Equatorial Asymmetry of East Pacific inter-tropical convergence zone (ITCZ)The location of the east Pacific intertropical convergence zone (ITCZ), a bandof area covered with convective clouds,
exclusively to the north of the equator (Fig.
1) has been a long-standing mystery. While
many theories explain this north–south
ITCZ asymmetry, observational verification is still required. Therefore, theproposed hypotheses are quantitatively Fig. 1 Geographical map of annual mean deep convective
examined. To achieve this, the equatorial
cloud cover (shaded) and SST (contour).
asymmetry of the east Pacific ITCZ is
explored on the basis of an ocean surface heat budget analysis performed using various satellite
data products.
The annual mean climatology of absorbed shortwave flux exhibits a marked meridional
asymmetry because of the reduction of insolation by high clouds in the north ITCZ. Ocean
mixed-layer advection has the greatest effect of counteracting this shortwave-exerted asymmetry. Although other heat fluxes, in particular latent heat flux, predominate over the advective heat flux in magnitude, they are secondary factors with respect to equatorial asymmetry(Fig. 2). The asymmetry in the advective heat flux originates from a warm pool off the Central
American coast and, to a lesser extent, the North Equatorial Counter Current, neither of which
exists in the southern hemisphere. The irregular continental geography presumably comes
into play by generating a warm pool north of the equator, and bringing cold water to the southin the far eastern Pacific.
In addition to the annual climatology, the north–south contrast in the seasonal cycle ofthe surface heat flux is instrumental in sustaining the north ITCZ throughout the year. The
northeast Pacific is exposed to a seasonal cycle considerably weaker than that in the southeast
Pacific. This is caused by multiple phenomena including the finite eccentricity of the Earth’s
orbit and the meridional gradient in mixed layer absorptivity. Simple experiments generating
synthetic sea surface temperature (SST) illustrate that the muted seasonal cycle of heat flux
forcing moderates SST seasonal variability inthe northeast Pacific, thus allowing the north
ITCZ to sustain throughout the year.
Existing theories on the ITCZ asymmetry
are briefly examined considering the present
findings: 1) The wind-evaporative-SST (WES)
feedback is active but considerably weak to entirely cause the equatorial asymmetry; 2) thestratus-SST feedback is a localized effect near
the South American coast; and 3) the upwellingSST feedback is limited to the equatorial cold Fig. 2 North–south contrast in zonal-mean heat fluxes:
absorbed shortwave (shaded), latent heat
tongue and is unlikely to help maintain the(solid), upwelling (dotted), long wave (dashed),
and advective heat (dot-dashed).
ITCZ.

23
Satellite Study of Atmospheric Forcing and Response to Moist Convection over Tropical and
Subtropical Oceans
Tropical convective clouds are often describedas “mediators” acting against large-scale forcing thatdestabilizes the atmosphere, such as moisture convergence and surface heat flux. This neutralizing
effect of convection was formulated by Drs. Aarakawa
and Schubert into the quasi-equilibrium hypothesis,
which has been widely accepted as the basis for many
cumulus parameterization schemes. On the other
hand, some recent studies discovered observational
evidence that necessitates updating the quasiequilibrium hypothesis as originally postulated.
Satellite data are analyzed to explore the thermodynamic evolution of tropical and subtropicalatmospheres prior and subsequent to moist convection in order to offer an observational test bed forconvective adjustment, which is important to thequasi-equilibrium hypothesis. Measurements by the
Tropical Rainfall Measuring Mission (TRMM) and
Fig. 3 Schematic representation of composite
Aqua satellites are projected on a composite temanalysis. TRMM and Aqua observations aremarked by clouds and line graphs, respecporal sequence over an hourly to daily time scale.
tively.
This is done by exploiting the temporal gap between
the local satellite overpasses that changes daily (Fig. 3). The atmospheric forcing and response
to convection are investigated separately for deep convective and congestus clouds. Convective
adjustment is quick and efficient in the deep Tropics during times when deep convection is
active. Moisture transport from the atmospheric boundary layer (ABL) to the free troposphereis evident in association with deep convection. However, the evolution of convective available
potential energy (CAPE) is controlled not only by ABL moisture but also extensively by coincident ABL cooling. CAPE exhibits a rapid drop for 12 h prior to convection and a subsequent
restoring phase lasting 1–2 days as the cool anomaly recovers (Fig 4a). ABL cooling is accompanied 180° out of phase by mid- to upper-tropospheric warming together comprising a bipolar temperature anomaly. The behavior of CAPE is considerably different when moist convection is caused by congestus clouds
with no deep convection nearby.
CAPE gently increases over a period of 1–2 days until congestus
clouds appear, then slowly declines to the initial level (Fig. 4b).
Convective adjustment is not efficiently at work even in the deep
Tropics when convective clouds
are not developed so deep in orderto penetrate the entire troposphere. The subtropical atmosphere shows no sign of convective adjustment regardles of thepresence of vigorous convection. Fig. 4 Composite CAPE for deep convection (a) and congestus clouds (b).

24 Division of Global – Scale Water Cycle Variations
Loboratory of Satellite Meteorology
Dual Ka-band radar system observation for the future Global Precipitation Measurement Mission
A dual Ka-band radar system was developed by the Japan Aerospace Exploration Agency(JAXA) for developing the global precipitation measurement–dual-frequency precipitation radar(GPM–DPR) algorithm. The dual Ka-radar system, which consists of two identical Ka-bandradars, can measure specific attenuation and equivalent radar reflectivity at the Ka band; boththese parameters are important, particularly for snow measurement. Using this dual Ka-radarsystem along with other instruments such as ground-based rain measurement systems andpolarimetric precipitation and wind profiler radars, parameter uncertainties in the DPR algorithm
can be reduced. Verification of improvement in rain retrieval using the DPR algorithm is also
included as an objective.
The basic concept of the measurement is to compare the same precipitation system in two
radars placed 10–20 km apart. The beam of the first radar is directed to match that of the second
radar. In general, the precipitation echo intensity decreases with range because of rain attenuation, which appears symmetrically in both radars. Through this method, the separation of equivalent radar reflectvitivy of precipitation and rain attenuation can be attained.
The dual Ka-band radar system is installed at the Okinawa Subtropical Environment Remote
Sensing Center, the National Institute of Information and Communications Technology (NICT),
where simultaneous observation of rain with a C-band polarimetric Doppler radar and groundrain observation instruments is currently under way. This radar is a frequency modulated continuous wave (FMCW) system with a relatively low transmitting power of 100 W and two offset
parabolic antennas that enable simultaneous transmission and reception. This system is highly
digitized with flexibility to adjust system parameters with observations and is equipped withthree observation modes: (1) nominal, with a 15 km observation range and 50 m range resolution; (2) long-range, with a 30 km observation range; and (3) high-sensitivity, with 250 m range
resolution.
Figure 1 shows the observation configuration in Okinawa Island. The two radar beams are
not an exact match because of the interference caused by a small mountain that exists between
the two radars. Near the middle point, instruments are installed to measure ground rain. Figure
2 shows an example of the precipitation echoes recorded by the two Ka-band radars on January
15, 2011. The two patterns appear symmetrical because both radars observe precipitation in

Fig. 1  Configuration of dual Ka-radar system observation.

Fig. 2 Precipitation echoes obtained fromdual Ka-radar system.

25
opposite directions. Strong rain attenuation in the Ka band causes a strong echo near one radar
and a rather weak detection near the second. This figure suggests the feasibility of specific rain
attenuation estimates obtained from this dual Ka-band radar system.

Study of Kuroshio’s impact on precipitaton using satellite data
The Kuroshio is a warm curent with the sea surface temperature (SST) warmer than thatof the surrounding ocean throughout the year. Precipitation generally occurs over warm SST
areas as a result of increased water-vapor and sensible-heat fluxes from the sea surface. In
this study, the Kuroshio’s influence on precipitation is investigated using the Global Satellite
Mapping of Precipitation_MVK+ (GSMaP_MVK+) product and data obtained from precipitation radar (PR) onboard the Tropical Rainfall Measuring Mission (TRMM) satellite. The
precipitation band along the Kuroshio appears after averaging GSMaP_MVK+ for 2003–2006.
To identify the type of precipitation system most often attributed to the Kuroshio, GSMaP_
MVK+ data are divided into several types according to synoptic scale disturbances. Composite analysis reveals that rain appears to be enhanced by the Kuroshio and that this band
mainly consists of precipitation associated with atmospheric fronts. Little precipitation
appears during cold-air outbreaks despite the strong atmosphere–ocean contrast in temperatures.
PR data provide various precipitation details including convective or stratiform precipitation types, storm height, and the vertical precipitation profile, in addition to near surface rain
rate, which allow us to study precipitation characteristics in greater detail. This analysis reveals that the Kuroshio plays a more significant role in the frequency of convective precipitation than that of precipitation intensity for convective or stratiform preciptation (Figs. 3 and
4). The frequency of convection at each altitude is investigated to observe the scope of theKuroshio’s effect, which is present up to 9 km and disappears at 10 km. An intersting featureis that the storm height over the Kuroshio appears lower in the winter. The surface windvelocity is also higher over or slightly northwest of the Kuroshio, which can be explained byvertical mixing. However, the rapid surface wind area does not exactly correspond to thelower storm height region.

Fig. 3  Location of the Kuroshio.

Fig. 4 Distribution of convective rain frequency.

26
Laboratory of Satellite Biological Oceanography
Seasonal and Spring Interannual Variations of Chlorophyll-a in the Yellow Sea and East China
Sea Using a New Satellite Data Set with Reduced Influence of Suspended Sediment
Increase in red tide and massive outbreak of giant jellyfish are known problems in the Yellow
Sea and East China Sea (YECS). It is speculated that eutrophication is one of their possible
causes. The occurrences indicated that the environmental conditions in YECS may be changing.
Furthermore, the construction of Three Gorges Dam in the upper stream of Changjiang River issuspected of influencing the environment of the YECS. Ocean color remote sensing data accumulated over more than 10-years, which can measure surface chlorophyll-a (Chl) as an index of
the amount of phytoplankton, is a good tool for examining interannual variations of Chl in the
YECS. However, it is suggested that the accuracy of the standard satellite Chl (standard SCHL)
is poor because of the high concentration of suspended sediment in the YECS. In this study, a
new SCHL algorithm, with reduced influence of suspended sediment, has been developed, andthe seasonal and spring interannual variations of new SCHL was examined with comparing
satellite-estimated total suspended matter (TSM) in the YECS.
The monthly new SCHL was lower than the standard SCHL at coastal areas and aroundthe Changjiang Hillock, where the bottom topography is shallow (< 50 m), from fall to early
spring. In summer, the area of the lower new SCHL was limited along the coast. These lower
new SCHL areas corresponded to high TSM areas.
TSM was low throughout the year in the middle of Yellow Sea and south off the hillock,and maximum SCHL was observed in April (Figs. 1b and b). It is considered that spring blooms
occurred in these areas. Correlation between SCHL and TSM was high, and the ratio of SCHL
in TSM was high. This indicated that variation of TSM mostly depended on concentration ofphytoplankton and that inorganic matter in the TSM was low at these areas (Figs. 2a and b).
Fig. 1 Seasonal variation of monthly new
SCHL (black circle) and TSM (whitecircle) averaged over 10-years in eacharea. (a) middle of Yellow Sea, (b) south
off Changjiang Hillock, (c) offshore of
Changjiang River mouth, (d) Changjiang Hillock, and (e) east off Changjiang
Hillock.

Fig. 2 Scatter diagram of 10-year averaged
monthly new SCHL and TSM in eacharea. (a) middle of Yellow Sea, (b) south
off Changjiang Hillock, (c) offshore of
Changjiang River mouth, (d) Changjiang Hillock, and (e) east off Changjiang
Hillock. Lines indicate the regression
line at the middle of Yellow Sea.

27
On the other hand, on the hillock the monthly SCHL was low with high TSM in winter andincreased with decrease of TSM starting from April, and maximum of SCHL was observed in May(Fig. 1d). It is considered that spring blooms occurred following decrease of the TSM because
growth of phytoplankton may be limited by low light conditions due to the high TSM in thatarea. In summer, maximum SCHL was observed and was probably due to the influence of Changjiang Diluted Water. In addition, the ratio of SCHL in TSM was as high as that in the middle of
Yellow Sea and south off the hillock (Fig. 2d). At offshore of the mouth, the monthly SCHL was
low with high TSM in winter and it increased with decrease of TSM in spring. However, maximum
SCHL was not observed, and maximum SCHL was observed in summer and the ratio of SCHL
in TSM was as high as that in the middle of Yellow Sea and south off the hillock (Figs. 1c and 2c)
Spring SCHL significantly increased at offshore of the mouth, and the increase might
correspond to the increase in the occurrence and magnitude of red tides. In the middle of
Yellow Sea, spring maximum of SCHL gradually increased significantly, and it seems to becaused by eutrophication.
From the new SCHL and TSM data, it is clear that spring blooms occurred at the highTSM areas as well as low TSM areas as a result of favorable light conditions due to decreaseof TSM. The increasing trend of the spring SCHL as well as summer in the middle of Yellow
Sea indicates the possibility of eutrophication.

Modification of Vertically Generalized Production Model for Turbid Waters of Ariake Bay, Southwestern Japan
Remotely-sensed ocean color cannot provide adequate information about oceanic primary
productivity (PP) without the support of models and sea truth data. Several models are being
used for deriving PP in the ocean. The vertically generalized production model (VGPM) formulated by Behrenfeld and Falkowski (1997a; henceforth BF) is one of the simplest and most commonly used models for estimating PP from satellite-based chlorophyll a (Chl a), sea surface
temperature (SST) and photosynthetically active radiation (PAR) data. Despite of considerable
understanding of the photosynthetic process and knowledge of the ocean optics that determine
ocean color signals, satellite-based PP often
have limited success in reproducing theobserved variability of PP data specificallyin coastal environments. This study attempts to develop a modified version of the
VGPM for a turbid coastal water.
The VGPM, basically designed for open
ocean waters, was evaluated with in situ
measurements of PP in the turbid coastal
waters of Ariake Bay. The VGPM-based
euphotic depth (Zeu)-integrated PP (IPP)significantly overestimated (x1-3) using insitu Chl a and SST, and it explained only
52% of the observed variability (Fig. 3a).
This large error could be partly because
the estimates from the sub-models for Zeu
B
and optimal Chl a-normalized PP (Popt)
suggested by BF overestimate and showed
weak correlations with in situ data. By
B
VGPM-based IPP obtained
substituting Popt
and Zeu with in situ values; Fig. 3 Scatter plots of in situ andBB
by using (a) modeled Popt
and Zeu, (b) in situ Poptandthe modeled IPP significantly improved
B
Zeu, (c) in situ Popt
and modeled Zeu, and (d) modified
accounting 84% of variability and showed
VGPM model. The solid and dotted line represents theregression line and the 1 : 1 line, respectively.
less overestimation (Fig. 3b).

28
The Zeu was the most important parameter influencing the modeled IPP variation in Ariake
Bay. BF suggested open ocean Zeu model based on surface Chl a, largely overestimated (x2-3)(Fig. 3c). A better estimation of Zeu in this turbid water could be obtained from in situ remotesensing reflectance (Rrs) by employing a quasi-analytical algorithm (QAA). Among the paramB
eters of the PP models, Popt
is considered to be the most important. However, in this study,
B
Popt was found to be of secondary importance and was difficult to be estimated from SST. The
estimation of Chl a was improved by optimizing a coastal algorithm with in situ Rrs data.
By incorporating the QAA-based Zeu, optimizing algorithm Chl a and using constantB(median) Popt
; the performance of VGPM was significantly improved in the study area (Fig. 3d).
Thus, although VGPM is a global open ocean model, when coupled with turbid water algorithms for Zeu and Chl a, it provided realistic estimates of IPP in the turbid water ecosystem.

Photoadaptive Response of Phytoplankton to Light Variation Caused by Wind and Tide: A Case
Study of Turbid Ariake Bay
In the ocean, light is one of the most important variables controlling primary production.
To maintain high photosynthetic efficiency in a variable light environment, phytoplankton
cells are known to respond to the variations of light. This study examines the influence oftemporal light variations caused by vertical mixing on photosynthetic pigment and efficiency
in Ariake Bay, Japan. Ariake Bay is known for its high turbidity caused by the large tidal amplitude, and it could be a suitable site for examining the influence of the light variations on
phytoplankton. Changes of photosynthetic pigment and the associated photosynthetic efficiency of phytoplankton under varying light conditions were examined under at different timescales of the vertical mixing caused by wind and tide.
Observations were conducted by T/V Kakuyo Maru of Nagasaki University on November 8(Cruise 1) and 15 (Cruise 2), 2008 and November 8 (Cruise 3) and 15 (Cruise 4), 2009. The timescale of light variations for phytoplankton was evaluated by vertical mixing time covering theeuphotic zone (teu) estimated by the diffusion coefficient (Kz) and the euphotic zone depth (Zeu).
teu =

Z2eu
2×Kz×602

Effects of different time scales of lightvariations on mean chlorophyll a (Chl a)specific diadinoxanthin (DD) and diatoxanthin (DT) pool size [(DD+DT)/Chl a]and on maximum quantum yield of photosystem (PS) II (Fv/Fm) were examined.
The shortest (4 h) and longest (27 d)
teu were observed at high (8.6 ± 0.5 m s–1)
and low (2.2 ± 0.8 m s–1) wind speeds during Cruises 1 and 3, respectively. Despiteof low wind speed, the intermediate values(10 hours) of teu were also found as a results of shallower Zeu caused by the tidal
current mixing during Cruises 2 and 4.
(DD+DT)/Chl a varied with diurnal cycle
and the average was higher for long teu(> 10 h) compared with that for short teu(< 5 h)  (Fig. 4). These results indicated thatphoto-protective response could be actively occurred during the longest teu. The
Fv/Fm in upper layers was higher during
long teu (> 10 h) compared with that during

Fig. 4 Time variation of (DD+DT)/Chl a and Photosynthetically Active
Radiation (PAR) for Cruise 1 (a), Cruise 2 (b), Cruise 3 (c) andCruise 4 (d). Opened rhombus symbols represent phytoplankton at the surface. Opened cycle and closed cycle symbols
represent the incubated phytoplankton under high light condition (100% PAR) and low light condition (1% PAR), respectively. Thin lines represent 1 minute-averaged incident PAR.

29
short teu (< 5 h). These results indicated that photo-damage to the Fv/Fm under high light conditions was caused by an inactive photo-protective response during short teu (< 5 h).
Therefore, the variation in the short time scale (teu < 5 h) in the light environment due tostrong wind may inhibit the photo-protective response and the photosynthesis of phytoplankton. To understand the primary production, it is necessary to examine how photosynthesischanges with short time light variations caused by wind.

Variations of Phytoplankton Photo-physiology and Productivity in a Dynamic Eutrophic Ecosystem
In coastal waters relatively high primary production occurs as a result of the supply of nutrients fromland. Local productivity usually shows a large, complex variations in both temporal and spatial scales
in response to changes in the availability of resources (light and nutrients) due to tidal movements andthe inflow of fresh water. In particular, under anthropogenically eutrophic conditions with typicallythin optical layers due to a strong attenuation, cells
undergo pronounced, short-term changes in a lightenvironment due to vertical mixing. Therefore, astrategy to acclimatize to a given light regime is crucially important for their growth and success. In thisstudy, using a fast repetition rate fluorometer(FRRF), we investigated the photo-acclimation stateof phytoplankton assemblages and the productivity
in the upper Gulf of Thailand (UGOT) which ishighly eutrophied due to anthropogenic loading.
Two onboard observations on November 2005
and July 2006 revealed the regional differences in
the photosystem (PS) II parameters, FV/FM, σPSII andthe maximum rates of Qa reoxidation (1/τQA). In par- Fig. 5 Relationships between underwater PAR
ticular, the profiles of 1/τQA apparently reflected theand instantaneous FRRF_based PB (a) for
Stn. 1, (b) for Stn. 5 in the upper Gulf ofregional differences in water column structures,
Thailand.
which corresponded to the photoacclimation response. These PS II parameters were used to estimate normalized productivity (PB) with aphotosynthetic model, and from in situ PB profiles; in addition, the photosynthesis-irradianceB) were determined. The(P-E) curves and the instantaneous euphotic zone (EZ)-averaged PB (PEZ
derived P-E parameters showed large differences between the upper stratified waters in Stn. 1
B
and well-mixed water column of Stn. 5; a higher α was found in Stn. 5 while Pmax
and the Ek
were higher in the Stn. 1 (Fig. 5; Table 1). This indicated that relatively high light-acclimated(or adapted) cells were dominant in Stn. 1, where they were sustained under brighter conditions
due to a strong halocline. On the other hand, cells in Stn. 5 had acclimated to a lower lightlevel as a result of deeper mixing. A significant (logarithmic) relationship was found between
B
PEZ
and the surface PAR from the data for all profiles data, which suggested that the column
productivity in the UGOT was principally
Table 1 The estimated P-E parameters for Stn. 1 and 5.
controlled by light availability. In addition,
this implied that, although cells were
exposed to different light regimes underless nutrient-stress, cells at different sites
might achieve a comparable potential
productivity due to adequate photoacclimation.

30
Laboratory of Bio-Physical Oceanography
Study of the Kuroshio axis movement associated with typhoon passage by using atmosphere–
ocean coupled model
We reproduced oceanic and metrological states around Taiwan before and after Typhoon
Haitang’s passage in 2005 for investigating the mechanism of the Kuroshio axis movement, which
was observed by long-range ocean radar (LROR) developed by the National Institute of Information and Communications Technology (NICT), Japan. We used the Cloud Resolving Storm Simulator (CReSS) developed by Tsuboki and Sakakibara (2002) as a meteorological model and theNonhydrostatic Ocean model for Earth Simulator (NHOES) developed by Aiki and Yamagata(2004) as an ocean model, and coupled both the models. The horizontal grid size of both themodels was 0.04°, and the vertical layers were divided into 100 layers by the NHOES with depths
ranging from 2 m to 100 m below the surface. The calculation period was 10 days from 0: 00
UTC July 14, 2005, the day when Typhoon Haitang spawned, to 0: 00 UTC July 24, 2005; Typhoon
Haitang made landfall on July 18, 2005. The calculated path of the typhoon was consistent withthat of the observed path. The model wind at Yonaguni Island was slightly stronger than the one
observed; however, the variation tendency was nearly identical. The Kuroshio flowed northeastward along the shelf edge in the model before the typhoon approached, as observed by LROR
(Fig. 1a and b). Southerly wind associated with the typhoon’s approach dominated northeast
Taiwan for one day until the Kuroshio axis changed the wind direction to northerly. The model
current pattern at 1 : 00 UTC July 21 coincides well with that of the LROR (Fig. 1c and d).
Volume transport across the shelf edge increased by 4 Sv when the wind direction changed
from northerly to southerly and then an anti-cyclonic eddy emerged on the shelf. The generationof an anti-cyclonic eddy is considered such that the water column obtained negative vorticity asa result of conservation of potential vorticity caused by the movement of the Kuroshio watersfrom deep to shallower area. Because the volume transport across the shelf edge increased periodically after the eddy formation, negative vorticity could be supplied continuously. It is, therefore,suggested that the anti-cyclonic eddies on the shelf caused the change in Kuroshio axis direction.
Fig. 1 Surface current field before typhoon
passage: (a) calculated by the model;(b) observed by LROR. Surface current
field after typhoon passage: (c) calculated by the model; (d) observed by
LROR.

Mean field and seasonal variation of sea surface current in the East China Sea
We obtained detailed, high-resolution spatiotemporal information of the sea surface current
field in the East China Sea (ECS) by combining satellite altimeter and surface drifter data, andinvestigated its temporal mean field and seasonal variation by analyzing this data.
The Kuroshio’s northeastward current with speeds greater than 50 cm s−1 along the continental
shelf slope; the Taiwan Warm Current flowing northward with speeds of 20–30 cm s−1, extending
from Taiwan Strait with a northward intrusion (~30 cm s−1) northeast of Taiwan; and the Kuroshio

31branch’s northward current with speeds of 10–20
cm s−1 west of Kyushu were steady (Fig. 2a). On
the other hand, an annual variation caused by thedevelopment of two different disturbances, which
propagated along the isobaths on the continental
shelf from the northeast Taiwan Strait and near
the Tsushima Strait (TS) to west of Kyushu, waspredominant in the seasonal disturbance. The
spatiotemporal scale and the propagation of these
disturbances can be explained by the dispersion
relationship of barotropic topographic Rossby
waves propagating in a steady flow. These disturFig. 2 Horizontal distribution of temporal mean surface current
bances also caused differences in the annual
vectors from May 1995 to January 2010: (a) annual
variations of current speed and axial position ofvariation in northward surface currents along (b) lines S
and (c) N. Shaded areas in (b) and (c) represent current
the Kuroshio branch between its southern andspeed with values greater than 15 cm s−1. Contour innorthern (lines S and N in Fig. 2a, respectively)
tervals for northward surface current are 1 cm s−1.
parts (Fig. 2b and c).
In summary, the annual variation was predominant in the seasonal disturbance of the surface
current field. This annual variation was caused by the propagation of the disturbance, which
behaved like topographic waves in a steady flow from the vicinity of the two straits. The seasonal variation west of Kyushu was especially influenced by these propagations in the ECS.

Tsushima warm current paths in the southwestern part of the Japan Sea
The Tsushima Warm Current (TWC) paths have been previously investigated by numerous
oceanographers; however, the correct current paths were unclear. In the present study, we createdsea surface current and dynamical height field information using satellite altimeter and Argos buoy
trajectory data recorded from May 1995 to January 2009. We then compared our sea surface current
data with geostrophic current components of the Argos buoy trajectories to reproduce and evaluate
the accuracy of our dataset. We examined the TWC paths in the southwestern part of the Sea ofJapan/East Sea, where TWC paths display high variability, using the dataset.
In the mean sea surface current field, the first branch of the TWC (FBTWC) through the eastern channel of TS flows along the Japanese coast and through north of Mishima Island. The
second branch of the TWC (SBTWC) flows along the continental shelf edge, and the third branchof the TWC (TBTWC) through the western channel of TS flows northward along the Korean coast.
We examined seasonal variation in the TWC paths. It is clear that the FBTWC and TBTWC
exist throughout the year with speeds greater than 15 cm
s−1. The SBTWC appears in August, continuing throughOctober. In other months, the SBTWC flows along thecontinental shelf edge with a small current velocity. Two
current axes are present nearshore and offshore of thecontinental shelf east of 131°E throughout the year. The
offshore current path appears from April to September.
It is considered that this current axis originated fromthe SBTWC and FBTWC, which could have been bifurcated after passing north of Mishima Island. The nearshore current flows through the west side of Oki with amean current speed of 20 cm s−1, and the current witha speed greater than 15 cm s−1 appears from January to
May and from August to December.
Our schematic view of the TWC paths in the southFig. 3 Schematic view of Tsushima Warm Current
western part of the Sea of Japan/East Sea, shown in Fig.
paths in the southwestern part of the Sea of Japan
3, is the first of its type to be documented.
analyzed from May 1995 to January 2009.

32 List of Publications* : Staffs, students and research fellows in the HyARC.

01.

02.

03.

04.

05.

06.

07.

08.

09.

10.

11.

12.

13.

14.

15.

Akter, N.* and K. Tsuboki*
Characteristics of supercells in the rainband of numerically simulated Cyclone Sidr. Scientific
Online Letters on the Atmosphere (SOLA), 6A, 25-28, doi:10.2151/sola.6A-007, 2010.
Bhatt, B.C., T.-Y. Koh, M. Yamamoto and K. Nakamura*
The diurnal cycle of convective activity over South Asia as diagnosed from METEOSAT-5 andTRMM data. Terrestrial, Atmospheric and Oceanic Sciences, 21(5), 841-854, doi:10.3319/
TAO.2010.02.04.01(A), 2010.
Hossen, M.S., T. Hiyama and H. Tanaka*
Estimation of nighttime ecosystem respiration over a paddy field in China. Biogeosciences Discussions, 7(1), 1201-1232, doi:10.5194/bgd-7-1201-2010, 2010.
Hutahaean, A.A.*, J. Ishizaka*, A. Morimoto*, J. Kanda, N. Horimoto and T. Saino
Development of algorithms for estimating the seasonal nitrate profiles in the upper water columnof the Sagami Bay, Japan. La mer, 48(2), 71-86, 2010.
Islam, M.N., S. Das and H. Uyeda*
Calibration of TRMM derived rainfall over Nepal during 1998-2007. The Open Atmospheric Science Journal, 4, 12-23, doi:10.2174/1874282301004010012, 2010.
Karev, A.R., D.-I. Lee, C.-H. You and H. Uyeda*
Variations in raindrop size distributions observed in mid-latitude ocean clouds during the EastAsian summer monsoon. Atmospheric Research, 96(1), 65-78, doi:10.1016/j.atmosres. 2009.11.014,
2010.
Lee, K.-O., S. Shimizu, M. Maki, C.-H. You, H. Uyeda* and D.-I. Lee
Enhancement mechanism of the 30 June 2006 precipitation system observed over the northwestern slope of Mt. Halla, Jeju Island, Korea. Atmospheric Research, 97(3), 343-358, doi:10.1016/j.
atmosres.2010.04.008, 2010.
Li, X., W.-K. Tao, T. Matsui, C. Liu and H. Masunaga*
Improving a spectral bin microphysical scheme using TRMM satellite observations. Quarterly
Journal of the Royal Meteorological Society, 136(647), 382-399, doi:10.1002/qj.569, 2010.
Ma, X., Y. Fukushima, T. Yasunari*, M. Matsuoka, Y. Sato, F. Kimura and H. Zheng
Examination of the water budget in upstream and midstream regions of the Yellow River, China.
Hydrological Processes, 24(5), 618-630, doi:10.1002/hyp.7556, 2010.
Masunaga, H.*, T. Matsui, W.-K. Tao, A.Y. Hou, C.D. Kummerow, T. Nakajima, P. Bauer, W.S.
Olson, M. Sekiguchi and T.Y. Nakajima
Satellite Data Simulator Unit: A multisensor, multispectral satellite simulator package. Bulletinof the American Meteorological Society, 91(12), 1625-1632, doi:10.1175/2010BAMS2809. 1,
2010.
Masunaga, H.* and T.S. L’Ecuyer
The southeast Pacific warm band and double ITCZ. Journal of Climate, 23(5), 1189-1208,
doi:10.1175/2009JCLI3124.1, 2010.
Minda, H.*, F.A. Furuzawa*, S. Satoh and K. Nakamura*
Convective boundary layer above a subtropical island observed by C-band radar and interpretation using a cloud resolving model. Journal of the Meteorological Society of Japan, 88(3), 285-312,
doi:10.2151/jmsj.2010-303, 2010.
Oue, M.*, H. Uyeda* and Y. Shusse
Two types of precipitation particle distribution in convective cells accompanying a Baiu frontal
rainband around Okinawa Island, Japan. Journal of Geophysical Research, 115, D02201,
doi:10.1029/2009JD011957, 2010.
Rafi uddin, M., H. Uyeda* and M.N. Islam
Characteristics of monsoon precipitation systems in and around Bangladesh. International Journal of Climatology, 30(7), 1042-1055, doi:10.1002/joc.1949, 2010.
Saba, V.S., M.A.M. Friedrichs, D. Antoine, R.A. Armstrong, I. Asanuma, M.J. Behrenfeld, A.M.
Ciotti, M. Dowell, N. Hoepffner, K.J.W. Hyde, J. Ishizaka*, T. Kameda, J. Marra, F. Mélin, A.
Morel, J. O’Reilly, M. Scardi, W.O. Smith Jr., T.J. Smyth, S. Tang, J. Uitz, K. Waters and T.K.
Westberry
An evaluation of ocean color model estimates of marine primary productivity in coastal and

33
16.

17.

18.

19.

20.

21.

22.

23.

24.

25.

26.

27.

pelagic regions across the globe. Biogeosciences Discussions, 7(5), 6749-6788, doi:10.5194/bgd7-6749-2010, 2010.
Saba, V.S., M.A.M. Friedrichs, M.-E. Carr, D. Antoine, R.A. Armstrong, I. Asanuma, O. Aumont,
N.R. Bates, M.J. Behrenfeld, V. Bennington, L. Bopp, J. Bruggeman, E.T. Buitenhuis, M.J. Church,
A.M. Ciotti, S.C. Doney, M. Dowell, J. Dunne, S. Dutkiewicz, W. Gregg, N. Hoepffner, K.J.W. Hyde,
J. Ishizaka*, T. Kameda, D.M. Karl, I. Lima, M.W. Lomas, J. Marra, G.A. McKinley, F. Mélin, J.K.
Moore, A. Morel, J. O’Reilly, B. Salihoglu, M. Scardi, T.J. Smyth, S. Tang, J. Tjiputra, J. Uitz, M.
Vichi, K. Waters, T.K. Westberry and A. Yool
Challenges of modeling depth-integrated marine primary productivity over multiple decades: A
case study at BATS and HOT. Global Biogeochemical Cycles, 24(3), GB3020, doi:10.1029/2009GB003655,
2010.
Shibata, T.*, S.C. Tripathy* and J. Ishizaka*
Phytoplankton pigment change as a photoadaptive response to light variation caused by tidal
cycle in Ariake Bay, Japan. Journal of Oceanography, 66(6), 831-843, doi:10.1007/s10872-0100067-z, 2010.
Short, D.A. and K. Nakamura*
Effect of TRMM orbit boost on radar reflectivity distributions. Journal of Atmospheric and Oceanic Technology, 27(7), 1247-1254, doi:10.1175/2010JTECHA1426.1, 2010.
Singh, P.* and K. Nakamura*
Diurnal variation in summer monsoon precipitation during active and break periods over central
India and southern Himalayan foothills. Journal of Geophysical Research, 115, D12122,
doi:10.1029/2009JD012794, 2010.
Sojisuporn, P., A. Morimoto* and T. Yanagi
Seasonal variation of sea surface current in the Gulf of Thailand. Coastal Marine Science, 34(1),91-102, 2010.
Son, Y.B., T. Lee, D.-L. Choi, S.-T. Jang, C.-H. Kim, Y.H. Ahn, J.H. Ryu, M. Kim, S.-K. Jung and
J. Ishizaka*
Spatial and temporal variations of satellite-derived 10-year surface Particulate Organic Carbon(POC) in the East China Sea. Korean Journal of Remote Sensing, 26(4), 421-437, 2010.
Takahashi, D.*, H. Miyake, T. Nakayama, N. Kobayashi, K. Kido and Y. Nishida
Response of a summertime anticyclonic eddy to wind forcing in Funka Bay, Hokkaido, Japan.
Continental Shelf Research, 30(13), 1435-1449, doi:10.1016/j.csr.2010.05.003, 2010.
Takahashi, H.G., H. Fujinami*, T. Yasunari* and J. Matsumoto
Diurnal rainfall pattern observed by Tropical Rainfall Measuring Mission Precipitation Radar(TRMM-PR) around the Indochina peninsula. Journal of Geophysical Research, 115, D07109,
doi:10.1029/2009JD012155, 2010.
Takahashi, H.G., T. Yoshikane, M. Hara, K. Takata and T. Yasunari*High-resolution modelling of the potential impact of land surface conditions on regional climate
over Indochina associated with the diurnal precipitation cycle. International Journal of Climatology, 30(13), 2004-2020, doi:10.1002/joc.2119, 2010.
Tripathy, S.C.*, J. Ishizaka*, T. Fujiki, T. Shibata*, K. Okamura, T. Hosaka and T. Saino
Assessment of carbon-and fluorescence-based primary productivity in Ariake Bay, south­westernJapan. Estuarine, Coastal and Shelf Science, 87(1), 163-173, doi:10.1016/j.ecss.2010.­ 01.006, 2010.
You, C.-H., D.-I. Lee, S.-M. Jang, M. Jang, H. Uyeda*, T. Shinoda* and F. Kobayashi
Characteristics of rainfall systems accompanied with Changma front at Chujado in Korea. AsiaPacific Journal of Atmospheric Sciences, 46(1), 41-51, doi:10.1007/s13143-010-0005-1, 2010.
Zhao, X., Y. Liu, H. Tanaka* and T. Hiyama
A comparison of flux variance and surface renewal methods with eddy covariance. IEEE Journalof Selected Topics in Applied Earth Observations and Remote Sensing, 3(3), 345-350, doi:10.1109/
JSTARS.2010.2060473, 2010.

Hydrospheric Atmospheric Research Center (HyARC)
Nagoya University
Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
Office:Telephone: +81-52-789-3466
Facsimile: +81-52-789-3436
Home Page: http://www.hyarc.nagoya-u.ac.jp/english/index.html

The 2010 Annual Report was published March 2012 by the
Hydrospheric Atmospheric Research Center (HyARC) Nagoya
University. Copies of this report are available from the officeof the Center.

Printed by Nagoya University COOP

Annual Report

Hydrospheric Atmospheric Research Center(HyARC)
Nagoya University

2010