福岡では1980年以降平均風速の減少が報告されている．本研究では、この平均風速の減少に着目し，過去26年にわたる風系の変化を季節ごとに詳細に調べ，福岡市域に流入する風の変化とヒートアイランド効果の関係について検討した．その結果，では，夏季において風速と気温との間に良い相関が見られ，熱対流によって引き起こされる局地風が卓越することが示された．また，冬季にはヒートアイランドに伴う対流ドームが強固となり，外部流である季節風の侵入が阻害され，風速が減少する傾向にあることが示唆された．この効果が，の平均風速の減少に寄与しているようである．

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局地降雨は周辺地域の地形の影響を強く受けるため, 地域によって局地降雨の形成過程は多種多様である. 九州北部の鳥栖・基山地域は東西に山系が迫り, 山系間の狭い平野地帯が南北の筑紫・をつなぐ地形となっており, 頻繁に局地降雨が発生する. 本研究では, この地域の風系と局地降雨の関係について検討し, また数値計算により実際に局地降雨が発生した日を再現させ局地降雨の発生機構について検討する, アメダスデータによると, 局地降雨の発生日にはでは玄界灘方向, 筑紫平野では有明海方向からの風が卓越することが明らかとなった. さらに, 局地降雨の発生時には40%以上の割合で両方向からの風90%の割合で少なくとも一方からの風が吹く. 玄界灘からの風に含まれる水蒸気量が20g/m³を越えると, 局地降雨の発生可能性が高くなる. 再現計算の結果では, 玄海灘からと有明海方向からの海風の発生が確認された.内陸では, 2つの海風の収束ラインが形成され, ライン上では強い上昇風の形成と比湿の増加が見られた.

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The vertical structures of nocturnal drainage winds that blow onto the Fukuoka Plains from mountains behind were examined on the basis of echo intensity and wind velocity obtained by using a Doppler sodar. Air and soil surface temperatures, wind velocity and net radiation near the ground surface were also measured to estimate the heat budget between the air and the ground. Though the nocturnal drainage winds have the depth of 250 m to 300 m, the shape of the fronts varies with the sea breeze and the surrounding flow. Twice in the nighttime, the occurrence of the horizontal wind with the maximum speed of 4 to 6 ms^-1 was observed at the height about 150 m above the ground surface. Though the ascending currents with the speed of 0.2 to 0.4 ms^-1 were also seen twice with the occurrence, the second current ascended higher than the first one. These phenomena may be due to the intermitted supply of cold air mass from a basin being in the upstream side. After the first occurrence, the air temperature near the ground surface reaches to the air temperature at a height of 30m. This reason is that the cold air near the ground surface formed by the radiational cooling is replaced with the upper warm air by the advection of the drainage winds. After then, the decreasing rate of the air temperature becomes smaller because the heat fluxes from the air toward the ground suppress the radiational cooling.

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The numerical experiment using a three-dimensional non-hydrostatic model (ARPS) was performed to examine the basic characteristics of the local wind on the Fukuoka Plains in Japan. The result shows a clear local wind circulation. The nocturnal local wind consisting of land breeze and mountain wind blows on the coastal area, t from 23:00 to 7:00. The diurnal local wind consisting of sea breeze and valley wind is induced from 8:30 to past 21:00. The horizontal air temperature distribution shows that the advection of mountain wind reduces inland temperatureat night and the advection of cold sea breeze in the daytime causes a temperature difference of 2°C between the coastal and inland areas. The heat budget ofthe atmospheric boundary layer was estimated using the calculation results. The local heat advection due to the nocturnal wind is about -60 W m^-2 over the plain. On the other hand, the local heat advection due to the diurnal windis -250 W m^-2 on the coastal area. This value is more than the half of the surface sensible heat flux. This shows that the cold air advection due to the sea breeze suppresses considerably the heating of the atmospheric boundary layer.

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福岡都市圏ではヒートアイランド現象が深刻な問題となっており, ヒートアイランド現象の実態を解明するため, 2003年夏から長期広域多点観測をおこなってきた. 本論文では, 人間の生活空間をとりまく熱環境の季節変化について検討するため, 得られた観測データをもとに, 夏季および冬季のヒートアイランド構造について解析する. ヒートアイランド強度は, 夏季・冬季ともに日中に小さくなる. 最も大きくなるのは冬季夜間で2.0℃以上になる. 夏季日中の福岡都市圏の気温分布は全体に高温域が点在する. 夏季夜間の気温分布は, 高温域が都心部に集中し, 郊外に向かうにつれて気温が低下するという典型的なヒートアイランド構造をもつ. 冬季日中は夏季日中と同様に全体に高温域が点在する. 冬季夜間は等温線が海岸線とほぼ平行に並び, 海岸に近い地域ほど気温が高く, 内陸に向かうにつれて低温になる.

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A numerical simulation was carried out to investigate the characteristics of sea breeze intrusion on the Fukuoka Metropolitan area by using ARPS and the results were compared with the field data of sea breeze obtained in August 2, 2003. The sea breeze front runs parallel to the costal line at the beginning of the sea breeze intrusion, but as it goes into the inland, the two-dimensional front becomes wavy and breaks. The sea breeze consists of the tail of about 600 m thickness and the head 1000 m and above high. The head is accompanied with a pair of upward and downward currents that reach to about 2000 m height.

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風向・風速出現確率分布図を用いて，1977_から_1980年と1999_から_2002年のそれぞれ4年間について，の風系を考察する．この表記方法を用いれば，風系を定量的に把握することができる．福岡の風系は20年前と現在では変化していることがわかった．特に，秋の風系が大きく変化している．これは，福岡の都市化による影響が大きいと考えられる．

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In order to examine the structure of urban heat island in the summer season, thermometers havebeen put in 71 instrument shelters of elementary schools in Fukuoka metropolitan area. A typical heat island pattern is seen by using the day-averaging air temperature in this area. The highest temperature of 26.4°C is observedaround Hakata JR Station. The heat island in the summer season appears more clearly in the nighttime, and the temperature inthe urban area falls at the rate of about 0.2°C/km toward the rural area. In the daytime, high temperature region of 28.0°C spreads over the whole area of the metropolitan. The heat island intensities in the nighttime and the daytime are 1.3°C and 1.5°C, respectively. Though the difference between daily maximum temperature and daily minimum temperature is 3.2°C at the region adjacent to Hakata Bay and reaches 5.1°C at an inner areaof Fukuoka plains.

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The so called location of settlements in Yayoi Age in the Fukuoka Plain, commonly known as well developed region in Yayoi Age, depended on the cultivation of rice plants. In this article, I examined their location by considerations of geographical conditions and by classifications of it into 7 types as follows:
A: On a upland-A-a: facing shallow valley A-b: facing valley bottom land A-c: the rest
B: On a lower terrace-B-a: near a flood plain B-b: the rest
C: On a flood plain-C-a: micro relief such as natural levee C-b: the rest
As a result of the examinations, I reached the conclusions as follows:
1) Some settlements of the latest period of Jomon(_??__??_)Age continued to Yayoi Age, while some did not. Their continuation depended upon whether or not they had shallow valleys where the soil was suited to the cultivation of paddy rice plants.
2) The A-a type and C-a type settlements prevailed in the early period of Yayoi Age and continued their existence for a long time. Both types had the shallow valleys or flood plains where the soil was suited to the rice plants cultivation. Some of C-a type settlenents ceased to exist. Considerating their relatively lower height in altitude, it could be assumed that they were destroyed by inundations of rivers.
3) The location of settlements in the middle period of Yayoi Age was of various types, due to the technical progress of the rice cultivation. Half of them were of A-a type. The fact showed that it was easy for Yayoi people to develop the shallow valleys. Therefore they developed them first and proceeded the settlements.
4) Among the newly located settlements in the middle period of Yayoi Age, the A-a type settlements existed for a long time and the A-c type and the C-a type settlements existed for a short time.
5) 65% of the location types of settlements in the later period of Yayoi Age were A-a type, the other types existed by just a few. The location types were still varied.
6) Through out Yayoi Age, the duration of the A-a type settlements were long, while that of the B-a type and the B-b type settlements were short. That of the C-a type settlements lay between them.
7) The long duration of the A-a type settlements was due to the fact that they suffered no flood damages situated on high elevations.

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The Kego fault runs through the central part of Fukuoka-city, extending southward to Kasuga, and Oonojo cities.
In order to estimate the fault activity during the Quaternary time and to clarify the fault's buried Quaternary topography, the author gathered drilling data in the area from Aratsu to Takamiya in Fukuoka-city, and examined the distribution of depth down to the base of the Quaternary strata lying on the Paleogene bedrocks.
The results obtained are as follows.
1. The basement on which the Quaternary strata lie changes in depth remarkably on the line connecting Aratsu and Hirao in Fukuoka-city. The basement on the southwest side of the line is shallower than 10 meters in depth, but on the northeast side, the basement is deeper than 60 meters in depth.
2. The largest difference in depth of the basement between two closely situated study points is as much as 53.0 meters at location b. Moreover, the largest gradient of the averaged slope between two study points is about 77°in the vicinity of location f.
3. It is difficult to assume the steep slope mentioned above has been formed by erosion. Thus, the slope is due to faulting along the Kego fault during the Quaternary time.
4. The Kego fault in Fukuoka-city consists of two echelon-arrange d strands a few meters apart: one is from location a to the west of location b, and the other is from location d to location f. These strands are situated 100 meters southwest to the fault line previously shown in“Fukuoka Jibanzu”.

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ブランチ型グリセロール・ジアルキル・グリセロール・テトラエーテル(ブランチGDGT )の組成に基づくMBT/CBT指標は、近年過去の気温を復元する手法として提唱された。 本研究では、このブランチGDGTを用いて、大分県大野川の河口で採取したボーリングコアと大野川上流の久住山山腹の露頭土壌から、過去10000年間の古気温復元を行った。

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弥生時代の開始期には,朝鮮半島南部からの文化の伝播によって,土器や石器などの道具だけでなく,生業や葬制にいたるまでの,広範な変革がみられる。そして,その時期には,遠賀川式土器という斉一性の高い土器様式が西日本に広がる。近年,この斉一性の再検討が進み,地域性のあることが指摘されるようになってきた。これは九州北部から東に行くほど,地理的勾配によって,無文土器を起源とする文化が薄れていくという状況のみではなく,在地的な影響力の重要性を指摘している。しかし,この時期の葬制をみた場合,その展開は極めて多様である。地理的勾配と在地的な影響もあるが,それのみでは,葬制の多様性と変化の大きさを説明することは難しい。
そこで本稿では,弥生時代開始期になって現れる副葬品である,朝鮮半島南部の文化に由来する磨製石剣,磨製石鏃,丹塗磨研壷,碧玉管玉に着目した。そして,(1)副葬習俗の展開における地域差,(2)土器様式と葬制の広がりの対応状況の有無を明らかとすることを目的とし,西日本各地におけるそれらの副葬品として扱い方,品目ごとの受容の様相を検討した。同時に,各副葬品の展開が,朝鮮半島との直接的な交流を示す部分がある可能性を考慮し,朝鮮半島での副葬品の在り方や地域性についても注意を払った。
そして,これらの検討を行った結果,弥生時代開始期の西日本では,九州北部を経由した文化を一様に受容するだけではなく,それぞれ地域性をもって受容することがわかった。そして,その様相は重層的であり,遠賀川式土器に代表される土器の影響は確かに九州北部から西日本に伝播するが,水稲農耕を中心とした農耕社会が形成され始めたのちは,九州北部を介さず,朝鮮半島南部の文化を各地域が選択して受容すると考えられた。一方,弥生時代前期を境に,九州北部では,石剣・石鏃などの武器副葬こそあまり受容しなかったものの,副葬習俗が一般化し始める。山陰地方では副葬品として管玉を主体的に受容するのみでなく,玉作りも展開させ,原材などの交易がみられるようになる。これらの様相から,弥生時代開始期に形成された地域性は,前期末の青銅器の伝播に伴う変化も加えつつ,弥生社会の副葬品による東西の不均衡や,地域的展開の基盤となると結論づけた。

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To understand the heat island structures of Fukuoka metropolitan area, 71 thermometers were set in the meteorological instrument shelters of elementary schools. In the present study, the data of air temperature obtained at the 71 sites in the summer seasons of 2003 and 2004 were analyzed to reveal the effect of sea breeze on the heat island structures. The classification of the occurrence of sea breeze and the non-occurrence were made based on the data of wind speed and wind direction at Fukuoka District Meteorological Observatory. In the case when the sea breeze was generated, the air temperature of the downtown area fell by about 4 °C at the maximum value. The wind speed of sea breeze and the fall of temperature are dependent on the amount of solar radiation for 1 hour after the intrusion of the sea breeze.

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