著者

武田 知己 小熊 宏之 石濱 史子 竹中 明夫

出版者

養賢堂

雑誌

農業氣象 (ISSN:00218588)

巻号頁・発行日

vol.66, no.4, pp.237-244, 2010-12 (Released:2012-12-03)

著者

武田 知己 小熊 宏之 石濱 史子 竹中 明夫

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.66, no.4, pp.237-244, 2010-03-10 (Released:2011-04-04)

参考文献数

5

被引用文献数

2 1

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Information on the ground surface can now be acquired easily and highly accurately using digital aerial photographs. A digital canopy model (DCM), which is calculated by subtracting a digital terrain model (DTM) from a digital surface model (DSM) of the vegetation, provides useful information for studies of wild animal habitats and plant species distributions. However, DCMs have been used mainly for forests, and their validity for herbaceous plants requires further verification. In this study, we used the ADS40 airborne digital sensor to clarify the relationship between a DCM and the height of herbaceous species. Our study area was the Watarase wetland in the northern Kanto Plain, central Japan. Suitable habitats for the many rare plants found in this wetland are maintained by controlled burning in early spring. We acquired three DSMs: just after the controlled burn in April 2006; in August 2006, when the vegetation height peaked; and in April 2007, also just after the controlled burn. We calculated the DCM based on the difference between the August DSM and a DTM developed by using the minimum height values from the two April DSMs. We also performed a field survey during the August DSM acquisition, during which we measured the height of the uppermost leaves with a measuring pole at 16 measurement points and estimated the vegetation structure from photosynthetic photon flux density (PPFD) profiles measured with quantum sensors at each point. The calculated DCM height correlated very well to the height of the uppermost leaves (r2 = 0.96), although it was about 100 cm lower. In contrast, the DCM and the height of maximum intercepted PPFD were highly correlated (r2 = 0.97) and showed a 1:1 relationship.

著者

杉浦 俊彦 阪本 大輔 朝倉 利員 杉浦 裕義

出版者

養賢堂

雑誌

農業氣象 (ISSN:00218588)

巻号頁・発行日

vol.66, no.3, pp.173-179, 2010-09 (Released:2011-07-26)

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モモにおける自発休眠覚醒期推定技術の開発に向けて、自発休眠覚醒効果の温度間差を‘白鳳’の生態実験により検討した。その結果、次のことが示された。1.自発休眠覚醒に対して最も有効な温度は6℃であった。6℃よりも温度が低下するに従って自発休眠覚醒効果は低下し、6℃の効果を1とすると、3℃では約0.9、0℃では約0.7であった。また、-3℃でも一定の効果が認められたが、-6℃では効果は認められなかった。2.6℃よりも高くなっても効果が低下し、9℃では約0.9、12℃では約0.6、15℃では効果は認められなかった。3.この自発休眠覚醒効果の温度間差について、変温条件下における妥当性を検討するため、これらの結果からチルユニットの係数を策定し、露地での自発休眠覚醒状況に適用したところ、よく適合した。

著者

岩田 拓記 浅沼 順 大谷 義一 溝口 康子 安田 幸生

出版者

養賢堂

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.65, no.1, pp.1-9, 2009-03-10

参考文献数

39

被引用文献数

2

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サーフェスリニューアル法を顕熱輸送モデルとして用いて,日中の平坦なマツ林上における複数高度での乱流観測から算出した鉛直長さスケールと乱流輸送の関連性を調べた。鉛直方向の積分長さスケールは大気不安定が強くなるに従い大きくなる傾向を示したが,Raupach <i>et al.</i> (1996, Boundary-Layer Meteorol., 78, 351-382) のシア長さスケールは大気安定度に比較的依存しなかった。これらの長さスケールを輸送渦の高さとして用い,サーフェスリニューアル法によって顕熱フラックスを算出した。渦相関法で算出したフラックスと比較した結果,異なる長さスケールを用いたサーフェスリニューアル法のパフォーマンスは不安定条件下で大きく異なり,積分スケールを用いた場合のフラックスの精度が最も良かった。これらの相違は長さスケールの安定度依存に関係していると考えられる。この結果は,渦のスケールを直接測定した積分スールをサーフェスリニューアル法において用いることが妥当であることを示している。また,乱流生成において浮力の影響が大きいときには,シア長さスケールは粗度層の渦スケールを表すのに制限がある可能性が示唆された。

著者

菅野 洋光 小沢 聖

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.55, no.4, pp.337-344, 1999-12-10 (Released:2010-02-25)

参考文献数

1

著者

福井 英一郎

出版者

The Society of Agricultural Meteorology of Japan

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.1, no.2, pp.145-152, 1944

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(1) 半旬期別平均値で調べると最寒期は日本の大部分の地方で第5期 (1月21日~25日) が之に相當し, 一部の地方 (裏日本西半部, 琉球, 臺灣) では稍々晩れて現はれるが之は此の前後に於ける雲量及降水量の最多期と一致する。最も高温なのは第45期 (8月9日~13日) に現はれる場合が最多く, 臺灣, 琉珠, 南九州, 甲信地方では之より早いが之も此前後を通じて雲量と降水量が最も少くなる時に當つてゐる。<br>(2) 寒の戻りは日本では第27半旬 (5月11日~15昭) に出現し, 此の場合は殆ど其時期が一致して場所によつての遲速が認められない。其原因として考へられるのは前線帯の通過で此時期に通過するものが最定時性を有つてゐる爲と考へられる。秋の殘暑は第58半旬 (10月13日~17日) に出現することが最も多いが氣温の上昇量は前の場合の低下量に比して可なり小さい。<br>(3) 氣温の昇降度を6半旬頃に區切つて求めて見ると春及秋に最大きな値を示す。之は前線や低氣壓の通過に基くものと考へられる。又其地理的分布は緯度及水陸配布の影響が最大きい。

著者

鈴木 義則 山本 薫

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.41, no.1, pp.9-15, 1985-06-10 (Released:2010-02-25)

参考文献数

7

被引用文献数

1

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In the western parts of Japan, there are frequent risks of frost damage on several crops such as tea plants, vine and others in the late spring. Experimental studies on protection of plants from the cold by sprinkling method utilizing latent heat of solidification were carried out to make establish practical application methods for the sake of saving water consumption.The main purpose of the experiments is to find the lowest value of effective sprinkling intensity under several air temperature conditions. Through discussions on the fitness of spray catching ratio, the experimental results were examined with the theoretical values by Niemann's and by the author's.Some results found in the experiments at cold night with radiative cooling are summarized as follows:1) Temperature of iced leaf under sprinkling could not increase up to 0°C under both conditions of lower air temperatures and smaller sprinkling intensity. There were clearly critical point of sprinkling intensity, which could maintain leaf temperature around 0°C. These points which are defined as the lowest value of effective sprinkling intensity were also changed with surrounding air temperatures. They became larger as air temperatures became lower. The relations between them was a linear one (Fig. 3.). Having compared the measured values with the theoretical values in their tendencies in the graph, it was found that the Niemann's one differed from the actual one especially in the lower temperature range but the author's one agree well throughout the giving range of temperature.2) The spray catching ratio measured using grouped branches with leaves of cranberry tree (Viburnum awabuki K. Koch) showed almost constant values in the range from 0.1 to 4.6mm·hr-1 of sprinkling intensity and was about 0.29 on average (Fig. 4.). The theoretical values by Niemann's method changed from 0.27 (at O°C) to 0.36 (at -4°C). On the other hand, the author's one was 0.27 (0--4°C), which was more close value to the experimental one.3) The fall-off of leaf temperature after 20 minutes of sprinkling-off changed proportionally to the initial leaf temperature, when air temperatures were -3.0--5.8°C. They became larger as initial leaf temperature became higher (nearly equal to 0°C). These relations were also changed parallely with air temperatures, that is, the fall-off of leaves temperatures became large as lowering of air temperatures.4) After re-sprinkling, the iced leaf temperature which was lowered to around air temperature began to increase showing the shape of saturation curve. The larger the sprinkling intensity was, the shorter the required time to make plant body temperature 0°C was. But in the case of smaller intensity of sprinkling, the required time became longer exponentially.

著者

Keiko Kai Mikiko Kainuma Naomi Murakoshi Kenji Omasa

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.48, no.5, pp.771-774, 1993 (Released:2010-03-16)

参考文献数

11

被引用文献数

4 8

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Strong correlations were found between blooming dates and meteorological factors. Based on these correlations, predictive maps of blooming dates in the Japanese Islands were proposed for each case of 1, 2 and 3°C of warming. The correlation was tested for the blooming dates of Prunus yedoensis, Prunus mume, Camellia japonica, Taraxacum, Rhododendron kaempferi, Wistaria floribunda, Lespedeza bicolor, Hydrangea macrophylla, Lagerstroemia indica, Miscanthus sinensis, etc., using the data of monthly mean temperatures, warming indices and cold indices from 102 meteorological stations in Japan between 1953-1990. Simple and multiple regression analyses were used for the correlation.Among meteorological factors, the strongest correlation was shown for monthly mean temperatures. Notably, the strongest was obtained for the case of Prunus yedoensis. The cold index and mean temperature of the previous December also showed the best correlation for species such as Prunus mume and Camellia japonica. Strong correlations between the leaf color-changing dates of Ginkgo biloba and Acer palmatum and the monthly mean temperature were found in one month of autumn. In these species, there was a delay of 2-7 days with a 1 degree increase in mean temperature.The 30-year 1km2 temperature-climate mesh-file developed by the Japan Meteorological Agency was used for the phenological estimation and predictive maps of blooming dates. Each observatory station was classified according to its annual mean temperature. Blooming for each mesh was estimated through monthly mean temperatures and regression equations of corresponding stations. Then, distribution maps of predictive blooming dates distinguished by 5-day divisions were made.

著者

庄野 浩資 天羽 弘一 高倉 直

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.45, no.2, pp.87-92, 1989-09-10 (Released:2010-02-25)

参考文献数

7

被引用文献数

1 2

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A method to detect cucumber fruits in the canopy using image processing technique has been studied, with the aim of robotic harvesting. This method distinguishes a fruit from the other parts of the plant, not by the difference in their colors, but by the difference in shapes.The brightness in the digitized image was differentiated in horizontal direction, and clipped into three values (+, 0, -) by two thresholds. Then ridge-lines were drawn between (+) value area and (-) value area.The ridge-line images ordinarily contain some noise from the other parts of the plant. Accordingly, two images for the same scene were taken, one was illuminated from the left and the other was illuminated from the right. The center line image was obtained by comparing the two ridgeline images in consideration of the shift of the fruit's ridge-line which was calculated by a model. After the noise was reduced in the center line image, the center line of the fruit remained.This method contains four unknown parameters, and it was found that these parameters have the optimum value. But there were some deviations in the optimum values obtained from different images. The deviations were not so severe as to make the detection impossible in our experiment, but in general it is necessary to determine the optimum values applicable to many other scenes.This method was applied to some images taken in the field, and showed that it was able to detect the fruit when it was fully illuminated from both sides. The detection, however, became difficult when the light was intercepted by leaves and the illumination for the fruit was not enough.

著者

林 真紀夫

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.40, no.3, pp.289-292, 1984-12-10 (Released:2010-02-25)

参考文献数

9

著者

ショウ ロバートエッチ

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.38, no.3, pp.339-342, 1982-12-10 (Released:2010-02-25)

著者

Shin NAGAI Shinpei YOSHITAKE Tomoharu INOUE Rikie SUZUKI Hiroyuki MURAOKA Kenlo Nishida NASAHARA Taku M SAITOH

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.70, no.3, pp.163-170, 2014 (Released:2014-09-10)

参考文献数

26

被引用文献数

6 10

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Long-term continuous phenological observation of cherry tree blooming is an important and challenging task in the evaluation of year-to-year weather and climate changes in spring in Japan. Here, (1) we performed daily field observations with a time-lapse digital camera in a deciduous broad-leaved forest in Japan from January 2004 to December 2013; and (2) we detected year-to-year variations in the blooming phenology of Prunus sargentii by visual inspection of the images and by image analysis. We found that (1) the red digital numbers (i.e., the digital intensity values of the red pixels; DNR) extracted from the time-lapse digital camera images tended to peak in full bloom; and (2) the green excess index (GEI) (based on the red, green, and blue digital numbers) tended to be lowest in full bloom. These results indicate that DNR and GEI are useful for detecting the timing of full bloom in P. sargentii.

著者

永田 修 矢崎 友嗣 柳井 洋介

出版者

養賢堂

雑誌

農業氣象 (ISSN:00218588)

巻号頁・発行日

vol.66, no.1, pp.23-30, 2010-03

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北海道石狩泥炭地に位置する、排水のみ行われた圃場(Dサイト)および、排水とさらに客土が行われた圃場(D-SDサイト)において亜酸化窒素フラックスの測定を2003年から2005年にかけて行った。D-SDサイトにおける亜酸化窒素フラックスは、-0.01から1.15mgN/m2/hrの範囲にあり、6月、10月に突発的に高くなる傾向がみられた。Dサイトの亜酸化窒素フラックスは、-0.01から1.15mgN/m2/hrの範囲にあり、2004年7月から10月にかけて顕著に高く推移した。この間のフラックスは、0.40から4.47mgN/m2/hrの範囲にあり、他の測定期間の最高値0.30mgN/m2/hrを上回っていた。フラックスが高くなった期間、土壌空気中の亜酸化窒素濃度も同様、顕著に高くなっていた。亜酸化窒素の年間発生量は、3.8から41.7kgN/ha/yrの範囲にあり、近傍の現存する湿原での測定値(0.3kgN/ha/yr)に比べ顕著に高い値であった。本研究から、泥炭土の排水、客土といった農地化は、亜酸化窒素発生量を顕著に増大させることが示された。土壌ガス中の亜酸化窒素濃度は、D-SDサイトに比べ、Dサイトで高く、その傾向は、特に、亜酸化窒素フラックスが高く推移した2004年で顕著であった。2004年は、他の2ヶ年に比べ5月〜8月の余剰降水量が顕著に多く、土壌がより乾かなかった測定年であった。本研究から、泥炭地を排水することによる農地化は、自然湿地に比べ、亜酸化窒素フラックスを顕著に増大させること、さらに、その亜酸化窒素発生量には、気象条件に伴う年次変動があることが示された。

著者

中川 行夫

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.29, no.2, pp.121-122, 1973-09-30 (Released:2010-02-25)

著者

斎藤 隆幸

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.23, no.2, pp.65-74, 1967-09-30 (Released:2010-02-25)

参考文献数

9

被引用文献数

1 4

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In order to study the nocturnal cooling of plant communities, the fall of temperature of a wheat field during night was calculated for various values of net radiation and of wind speed above the surface of the wheat field, 60cm height and with 4.4 of L A I. The results of the calulation were compared with the fall of temperature of the bare soil surface during night.As it is observed that the thermal condition of the plant layer is approximately in equilibrium for the time just before sunrise, the vertical distribution of leaf temperatue, air temperature and water vapour density within the plant layer at the time of sunrise are calculated with various values of net radiation and of wind speed at the height 40cm above the surface of the wheat field on the assumption of equilibrium condition.The calculated profiles of leaf temperature and air temperature for 0.10cal·cm-2·min-1 of net radiation are shown in Fig. 4 for the values of 0.5m·sec-1 and 3.0m·sec-1 of wind speed. It is seen from Fig. 4 that difference between the temperatues of the upper part of plant layer and of soil surface under the plant layer is about 9.0°C for 0.5m·sec-1 of wind speed and about 0.5°C for 3.0m·sec-1.The fall of temperature during night was obtained from the difference between the calculated value of temperature and the temperature at the time of sunset. The temperature at the time of sunset was assumed to be equal to that at the top of the inversion layers. The fall of leaf temperature of the upper part of the wheat field, shown in Fig. 3, is in very close agreement with observational values. As seen in Fig. 3, the temperature fall increases rapidly with decreasing the wind speed below 1m/sec.The fall of temperature of the bare soil surface was also calculated for the radiation values and the wind speed at the height 50cm above the soil surface. The calculated results of the fall are in good agreement with those of BERLYAND (1956). The variation in the fall of temperature of the bare soil surface with wind speed is not so apparent as in the case of the wheat field.By use of both calculated results of the wheat field and of the bare soil surface, comparison was made of the fall of temperature of the upper part of the wheat field and of the bare soil surface under the same meteorological conditions. From the results it can be inferred that the night minimum temperature of the upper part of the wheat field is lower than that of the bare soil surface for the condition of calm wind, but that for windy condition the reverse is the case.

著者

林 陽生

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.48, no.1, pp.57-64, 1992-06-10 (Released:2010-02-25)

参考文献数

15

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To investigate dependencies in the magnitudes of a waving ear on mean wind speed, field observations were carried out over a barley filed in the ripe stage. Fluctuating displacements derived from HONAMI were measured using a newly designed 2-dimension strain sensor. The velocity fields were measured by a sonic anemometer-thermometer.A coherently waving phenomena of HONAMI appeared and was evaluated by the fluctuating displacements of a single ear of the stand. Dividing a time series of the fluctuating displacement into five typical bands of frequency by use of an analog filter, it was shown that there are two dominants of 0.5-Hz and below 0.1-Hz in the original. The bands were from a natural frequency and a gustness of wind respectively. Comparing the amplitudes, the natural frequency contributed remakably to the original fluctuation of HONAMI.Magnitudes of an instantaneous ear-displacement, which represents 0.5-0.6-Hz of frequency, varied with increments of the mean wind speed within a range of 2.6-4.4-m/s. Except for this range, the dependency between the amplitude and the wind speed was not clear.Instantaneous changes in lateral displacements and velocity fluctuations were quite similar except for the component of higher frequencies. Under such circumstances, an ear-displacement will appear to infulence strongly the aero-dynamical properties of the canopy boundary layer.The force per unit length acts on a waving ear generates by a relative velocity of u-dx/dt. Here, u is the mean wind speed, and dx is the displacement of an ear from its mean position during dt. Using this concept, drug force was evaluated under two criteria for leeward ear-moving and ear-standing. Under the windy conditions, the force loaded on an waving ear reduced by 10% against the standing criterion with dx=0. On the other hand, the reduction rate became small down to 4% of the standing criterion under the condition of weak wind.

著者

高山 成 木村 玲二 神近 牧男 松岡 延浩 張 興昌

出版者

養賢堂

雑誌

農業氣象 (ISSN:00218588)

巻号頁・発行日

vol.60, no.3, pp.173-189, 2004-09-10

被引用文献数

5 8

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黄土高原における砂漠化対処に必要な環境モニタリングを目的として、降水の特性について検討した。まず黄土高原における年降水量について、空間分布、安定性(ばらつき)、トレンドを調べた。次に降水の季節パターンに着目し、夏季を中心とした雨季において、降水がどの程度安定して出現するかについて検討した。はじめに1980年から2000年までの53地点の日降水量データを基に、Boosrap法より年平均降水量の区間推定を行った。さらにこの区間推定値を基準として年降水の時系列トレンドを調べた。次に1年を5日間単位の期間に分け、各期間の期間降水比{PRP(、j)}と降水安定度{PSI(、j)}との関係より、各地点における降水の季節パターンについて検討した。年降水量の平均はengeri(騰格里)砂漠、Wulanbu(ウランブ)砂漠の周辺(N38-41°、E104-107°)で最も少なく、低緯度になるほど降水量は増加した。しかし、2つの砂漠の西側に位置するQuilian(チーリエン)山脈周辺の地域(N37°30'、E101°20')は多降水な地域であった。また、Maowusu(毛烏素)砂漠北部とWulanbu砂漠北東の地域、Wugong(武功)周辺の地域は、年降水量の変動が最も大きいが、Quilian山脈周辺の多降水地域やその南方の山岳地域などは年降水の変動が小さかった。年降水量のトレンドについては黄土高原全域を平均した場合、有意なトレンドは見出せなかった。しかし、個別の観測点について見た場合には、数箇所の観測点で増加または減少のトレンドを有する可能性が示唆された。本研究では期間降水比{PRP(、j)}と降水安定度{PSI(、j)}との関係から雨季安定度{RSS(j)}を提示し、夏季を中心とした雨季における降水の安定度(変動度)を評価した。その結果、黄土高原においては同程度の年降水量の地域であっても、東側地域が西側地域よりも雨季に出現する降水が不安定であることが明らかとなった。

著者

Toshichika Iizumi Gen Sakurai Masayuki Yokozawa

出版者

日本農業気象学会

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

pp.D-13-00023, (Released:2014-04-03)

参考文献数

42

被引用文献数

3 10

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The consequences of observed changes in climate and management on yield trends in major crop-producing regions have implications for future food availability and access. We presents an assessment of the impacts of historical changes in sowing date and climate to the maize yield trend in the United States (U.S.) Corn Belt from 1980 to 2006, using large-area crop modeling and data assimilation technique (the model optimization based on the Markov Chain Monte Carlo method). The model calibrated at a regional scale successfully captured the major characteristics of the reported changes in yield and the timing and length of maize growth periods over the Corn Belt. The simulation results using the calibrated model indicate that while the climate change observed for that period likely contributed to decrease the yield trend, the positive contribution from the reported earlier shift of sowing date offset the negative impacts. With given spread in the assessment results across previous studies and this study, the credence of the conclusion that the negative impacts of the climate change on the U.S. maize yield trend are more likely attributed to the decreasing growing-season precipitation trend than to the temperature trend increased. This study addressed an emerging use of large-area crop modeling and data assimilation to attribute observed change in crop yield trend to climate and management.

著者

OKADA Maki KUSAKA Hiroyuki

出版者

Society of Agricultural Meteorology of Japan

雑誌

Journal of agricultural meteorology (ISSN:00218588)

巻号頁・発行日

vol.69, no.1, pp.23-32, 2013-04

被引用文献数

24

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Globe temperature is one element of the heat stress index, the Wet Bulb Globe Temperature, which is used to evaluate how radiation adds to thermal discomfort in the workplace. As the measurement of globe temperature is not standardized, empirical equations were introduced to estimate the globe temperature from weather factors, including air temperature, solar radiation and wind speed. As it was not known whether these equations were applicable in an urban park environment with vegetation, we observed the globe temperature using a set of instruments in three parks. The observation along with the heat balance analysis of the globe revealed that the globe temperature depended curvilinearly on solar radiation and that wind speed influenced this dependence. We compared two previously proposed empirical equations to the observed globe temperature and found both equations had systematic estimation errors. Although the errors were reduced by fitting the equations to the observed data and reevaluating their numerical constants, the equations still had shortcomings, as one did not consider wind speed and the other included a discontinuity. We therefore derived a new equation based on the heat balance equations of the globe with its numerical constants experimentally determined. This equation was able to predict the curvilinear dependence of the globe temperature on global solar radiation without any discontinuity, and it also showed the globe temperature response to wind speed.

著者

丸岡 知浩 伊藤 久徳

出版者

養賢堂

雑誌

農業気象 (ISSN:00218588)

巻号頁・発行日

vol.65, no.3, pp.283-296, 2009-09-10

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植物の開花や落葉などの時期は、気温に密接に関連している。従ってこれらは地球温暖化の影響を受けやすいと言える。実際、Walther et al.は近年の気温上昇の影響を受けて、植物の開花や落葉などの時期が変化していることを報告した。一般的には温暖化とともに、開花は早くなり、落葉は遅くなる。しかし暖地では冬季に十分な寒さを経なくなるので、休眠打破が遅れ、開花が遅くなることも指摘されている。日本のサクラも例外ではない。近年の気温上昇傾向を受けて、サクラの開花の時期は早くなっている。しかし冬季に暖かいと休眠打破が遅れ、開花が遅くなることも知られている。その典型が2007年であった。この年は暖冬で、全体的には開花日が早まったが、南九州や八丈島などの暖地で極端に開花が遅くなる現象が見られた。特に八丈島では観測史上初めて満開には至らなかった。本研究では、DTS(温度変換日数)法に基づきながらも、全国一律のパラメータを用い、予測したい期間の気温のみで休眠打破の時期、開花日までを予測できるように開花モデルを作成する。また、さらに現在気候において開花しない名瀬と開花の南限である種子島のデータを使用することによって、開花そのものの有無の判定基準を作成する。そしてその開花モデルを将来の予測気温に適用し、将来の開花を予測する。