Tsukuba Geoenvironmental Sciences, Vol. 2, pp. 19-24, Dec. 26, 2006

Meteorological Observation Station at the summit of Mt. Tsukuba
Yousay HAYASHI* and Research Group for Intramural Project (S), University of Tsukuba

Abstract
In regional scale, to answer a wide range ofmeteorological and hydrological subjects, University ofTsukuba decided to conduct a research project entitled“Multi Monitoring of Meteorological and Hydrological
Elements at Mt. Tsukuba and Analyses for Atmosphereand Water Cycles” in 2005. To perform this objective,
research activities by means of an automated weathersystem (AWS) have been performed at the summit of Mt.
Tsukuba, i.e. at an altitude of 871m, since January 1, 2006.
Sections of measurement of hydro-meteorologicalprocesses and data communication were designed forlong term environmental monitoring by multiple sensors
and simultaneous transportation of the real time databy internet facilities. Also scientific interests focus onsynoptic futures of the meteorological and hydrologicalstatuses influencing regional environmental changes in thelower part of the atmospheric boundary layer. The sitespecific database observed at the summit of Mt. Tsukuba
also contributes to use temporal and spatial information
not only on scientific approaches but on practical use forweather interpretation.
Currently, sixteen items of meteorological andhydrological terms are available for several integrated
data files. It is expected that the observation succeeds theacademic legacies from the past achievements provided bygreat deal of labor through this 100 years.
Key words: Mt. Tsukuba, water cycle, global warming,
multiple measurements, environment monitoring

The meteorology and hydrology research group at
the graduate school of life and environmental sciences,
University of Tsukuba, launched a meteorologicalobservation station in January 2006 in the former
Tsukuba-san AMeDAS (Automated Meteorological DataAcquisition System) facility on the top of Nantai-san(871m), the west peak of Mt. Tsukuba (Photo 1), as an
intramural research project (S) for 2005, in Universityof Tsukuba. This project is entitled “Multi Monitoringof Meteorological and Hydrological Elements at Mt.
Tsukuba and Analyses for Atmosphere and Water Cycles”,
and headed by Professor Y. Hayashi with eight researchers
listed in the last part. Currently, the following home pageaddress has been open to the public; http://mtstukuba.suiri.
tsukuba.ac.jp/.
2. Scientific function
It is expected that the observation succeeds theacademic legacies from the past achievements provided bygreat deal of labor through this 100 years at Mt. Tsukuba.
The most practical and valuable feature of the observation
at Mt. Tsukuba is that they can carefully observe the lower
part of atmospheric boundary layer lying over the Kanto
plains, which are including individual atmospheric eventsand backgrounds of water cycles characterized by anextent of the Tsukuba-Kasumigaura area.
Research subjects expected are represented by thefollowing two topics. Firstly, due to the very hightemporal and spatial variability, there is insufficient

1. Introduction
As global warming and other environmental problems
worsen, it is becoming increasingly important to obtain an
accurate apprehension of the status of our environment.
Especially, changes in meteorological and hydrologicalprocesses are matters of concern under ongoing global
warming. The first step on an approach should bepromoted is to make observations at a standard location
representing the surrounding conditions.

*Graduate School of Life and Envionmental Sciences,
University of Tsukuba, Japan

Photo 1 Distant view of Mt. Tsukuba

19Y. HAYASHI and Research Group for Intramural Project (S), University of Tsukuba

information about details of the hydrological cycle. The
lack of empirical data leads to specific problems of how toincorporate hydrological processes in regional weather andlocal climate systems. To improve our understanding andpredicting abilities of the energy and hydrological cycle,
the current observation station will work as a researchplatform. The hydrological and meteorological observed
data are basically important for this purpose. Also, isotope
tracer is very effective to investigate the hydrological andmeteorological path and flux in an area. Prior research
projects were carried out under external research fundof JSPS since 2002. To follow these academic activities
in University of Tsukuba, the present observation canprovide new scientific findings.
Secondly, partition of magnitude in recent temperaturerise into two causes of heat island effect and of globallyrising temperature regime. The past database observed
at Mt. Tsukuba through 1976 to 2004 indicates a clear
increment of monthly mean temperature in both winterand summer seasons. Here, it can be deduced that ordinary
defined temperature rise by global warming is calculatedusing available data distributed generally in urban area.
When we can compare temperature changes at Mt.
Tsukuba with such an urban station’s, subtracted values
between two stations corresponds conceptually with theheating by urbanization itself. In this manner, when it iscomparing at Mt. Tsukuba and at Tokyo in winter, thetendency of the temperature rise arose by 2.5 times fasterat Tokyo than at Mt. Tsukuba. It is expected that the newly

acquired database at Mt. Tsukuba is giving a support tothis fact.
3. History of the meteorological observation at Mt.
Tsukuba
Meteorological service in Japan was initiated in 1875
by the Tokyo Meteorological Observatory within theMinistry of the Interior. This was renamed as the Central
Meteorological Observatory (CMO) in 1887 and wastransferred to the Ministry of Education in 1956. As
modernization progresses, the Meteorological Agencyof Japan (JMA) placed under the Ministry of Land,
Infrastructure and Transport, serves as one of the mostadvanced and leading National Meteorological Services in
the world and discharges both national and international
responsibilities.
History of meteorological observation at Mt.
Tsukuba goes back to the 1900’s when the CMO wasconstructed and is listed in Table 1. In 1902, an equipped
meteorological observatory at the summit of Mt. Tsukuba,
said Yamashina-no-Miya Tukuba-san Observatory, wasdesigned and realized by a house of an imperial prince. In
those days, Mt. Tsukuba was recognized as an observation
tower sounding atmospheric boundary layer. However,automated systems were not yet being conducted. The
station was donated from Yamashina-no-Miya to the CMO
in 1906, and used for observing meteorological conditionsof strategic importance. After that, under the Ministry ofLand, Infrastructure and Transport, regular observation by

Table 1 History of meteorological observation at Mt. Tsukuba

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Meteorological Observation Station at the summit of Mt. Tsukuba

automated facilities continued till 2001.
The JMA has operated automatic meteorologicalobservation stations over whole of the Japaneseislands, which have been known as the AMeDAS. Fourmeteorological elements of air temperature, wind speed
and wind direction, sunshine duration and precipitation
had been available. A station named Tsukuba-san wasconstructed as one of the AMeDAS network in 1976, but
it was terminated in 2001. Closing of this station was due
mainly to development of measuring systems of windprofiler, although observation records at Tsukuba-san had
covered officially over last 100 years.
4. Facility of the new observation station at Mt.
Tsukuba
The newly designed meteorological observation station
was equipped at the summit of Mt. Tsukuba, where islocated approximately 20 km north of Kasumigaura,
Ibaraki Prefecture (Fig. 1). It enables to act as a role
substituting for the above mentioned historical observation
at the summit of Mt. Tsukuba. Instruments attachedwere approved their accuracy by the JMA. Mt. Tsukuba
constructs a mountainous area along fringe of the northernpart of the Kanto Plains and forms an isolated mountain.
The body of the mountain consists of two peaks of Nantaisan (871 m) and Nyotai-san (877m). In order to take over
the assets of observation records, which lasted for over
100 years, the instruments were installed at observation
filed of the former AMeDAS located at the summit ofNantai-san.
Even now, the building of the old observatory isvery solid architecture having a three-storied structure(Photo 2). Since the termination of the AMeDAS in
2001, preservation of the building is under a religious
corporation of the Tsukuba Shinto shrine. Accordingly, topromote this project, University of Tsukuba exchanged apractical contract with the religious corporation.
The plane view and vertical view of the observation
station are shown in Fig. 2 and Fig. 3 respectively. From apoint of view of continuity from the AMeDAS in quality,
the ground level observation set up at a field locating thesouthwest side of the building (Photo 3). Sensors for windand radiation were installed at housetop of the building.
Data logging and communication parts of the system
occupied a small room on the first floor of the building
nearby the ground observation field. All instruments
were installed referring to the prior condition of the field
instrumentation of the former AMeDAS as possible. Table
2 indicates observation elements and related information

Photo 2 Building of the old Tsukuba-san meteorologicalobservatory constructed by CMO in 1929

Fig. 1 Location of Mt. Tsukuba

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Y. HAYASHI and Research Group for Intramural Project (S), University of Tsukuba

Fig. 2 Plane view of the observation station

Fig. 3 Vertical view of the observation station and equipments

for installation. Principal elements are wind direction(WD), wind speed (WS), air temperature (Ta), relative
humidity (RH), soil temperature (Ts), surface temperature(Tsf), solar radiation (Rs), downward short wave radiation(Rs-down), upward short wave radiation (Rs-up), airpressure (P), precipitation (Pr), rain pH (pH), electric
conductivity of rain (EC), CO2 concentration (CO2), pollen
number suspended (KFN), and weather conditions (PDW)
including weather type and visibility.
Apart from physical aspects, the summit of Mt. Tsukuba
has been widely praised for it scenic view of the Kanto
plains. Then, in order to watch the phenological changesof the surrounding ecosystems, such as buds of Japanese22

Photo 3 Ground level observation at the summit of Mt.
TsukubaMeteorological Observation Station at the summit of Mt. Tsukuba
Table 2 Measuring elements of the new observation station at Mt. Tsukuba
ElementWind direction/Wind Speed
Air temperature
Relative humidity
Soil temperature
Ground surface temperature
Solar radiation
Downward short wave radiation
Upward shor wave radiation
Air pressure
Precipitation
Rain acidity
Rain electric conductivity
Concentration of carbon dioxide
Pollen number suspended
Present weather
Camera image

Sensor Location
Sensor/Method
3m above the loof top *RM.Young/Wind vane
1.5m above the ground
Climatec/Electorical-registance
1.5m above the ground
Vaisala/High polymar film
1cm under the ground
Climatec/Electorical-registance
2.4m above the ground
Tasco/Infrared thermosensor
1.55m above the loof top *Kip & Zonen/Termocouple
1.4m above the loof top *EKO/Photo diode1.4m above the loof top *EKO/Photo diode1.45m above the ground
Vaisala/Silicon capacitance
1.1m above the groundOgasawara/Tipping-bucket/Heater
1.1m above the groundKyoto Denshi Kogyo/Glass electrode1.1m above the groundKyoto Denshi Kogyo/Four electrodes
3.1m above the ground
Vaisala/Two single beam
1.9m above the groundYamato Seisakusho/Semiconductor laser
2.4m above the ground
Vaisala/Forward scattering
8.5m above the ground
SONY/Network* height of the loof top: 12m

beech or rice planting season, a web camera was attachedat the southwestern corner of the building. Format of theimage is JPEG and corded by time and date. Important
flames of the images are preset with 10 minutes interval.
These multi monitoring system designed by the present
project will cover almost all of phenomena representing
environmental conditions in the atmospheric boundary
layer around Mt.Tsukuba.
Observation was started officially on January 1, 2006.
Data recording categories are shown by the following typesof data; 10 minutes base data set (MtTsukuba_TBL100),hourly base data set (MTTsukuba_TBL160) and daily
base data set (MtTsukuba_TBL124) for every element.
And data sets of pollen count number and water quality
are named as MtTsukuba_KFN and MtTsukuba_RAIN
respectively, which are provided by the same time stamps
as meteorological data.
5. RemarksPhysically based descriptions of the environmental
changes are important. The newly designed observation
station provides benchmarks for meteorology andhydrology under changing environmental conditions.
The launch of the meteorological observation station atMt. Tsukuba not only revives the function of AMeDAS
eliminated in 2001, but also starts a new comprehensive
atmosphere and water circulation field research project,incorporating new meteorological instruments, image
cameras, CO 2 and acid rain observation equipments,and other systems that take monitoring of the global
environment into consideration.
In this project, University of Tsukuba takes over
100 years of valuable meteorological observation. And

the project group will clarify meso-scale atmosphericcirculation around Mt. Tsukuba, and studies water andmaterial circulation in the region ranging from Mt.
Tsukuba to the Kasumigaura watershed, and conduct
analyses to distinguish global warming from temperaturerises due to the heat island effect. The project will also
contribute to regional society through use of observationequipment and data in meteorological, hydrological,
and environmental education and quasi real-time data
disclosure.
Member of the research group
Asanuma, Jun (Hydrology):
asanuma@suiri.tsukuba.ac.jp
Hayashi, Yousay (Climatology, Head of the project):hayyou@atm.geo.tsukuba.ac.jp
Tase, Norio (Hydrology):
tase@atm.geo.tsukuba.ac.jp
Tsujimura, Maki (Hydrology):
mktsuji@atm.geo.tsukuba.ac.jp
Ueda, Hiroaki (Climatology):
hueda@sakura.cc.tsukuba.ac.jp
Ueno, Kenichi (Meteorology):
kenueno@sakura.cc.tsukuba.ac.jp
Watarai, Yasushi (Meteorology):
watarai@suiri.tsukuba.ac.jp
Yabusaki, Shiho (Hydrology):
yabusaki@suiri.tsukuba.ac.jp
Yamanaka, Tsutomu (Hydrology):
tyama@suiri.tsukuba.ac.jp
Received 22 September 2006
Accepted 28 November 2006

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