Distribution of winter precipitation in Japan was compared for the cases of warm and cold win-ters. In winter, the Japan Sea coast area has a great deal of precipitation brought by the NW mon-soon, whereas the Pacific coast area is dominated by dry weather because the mountains have a “rain shadow” effect against the NW monsoon. Precipitation along the Pacific coast is ordinarily brought by extratropical cyclones passing through off the coast of the Pacific Ocean. Sometimes cyclones emerge in the Japan Sea and bring some precipitation in the area of the Japan Sea coast.
In cold winters the contrast in distribution of precipitation between the Japan Sea coast and the Pacific coast becomes more marked because of the more persistent and severe NW monsoon. In warm winters, however, such contrast becomes obscure and cyclone precipitation dominates the whole country (Fig. 5).
Six winters were selected as warm and cold winters from 27 winters (1953/54-1979/80) by the following method. A winter surface temperature (three months: Dec. -Feb.) was represented by nine 10-day mean values. When the 10-day value was higher (lower) than the normal by one standard deviation, it was counted as a warm (cold) 10-day period. The numbers of warm and cold 10-day periods were counted for ten meteorological stations (see Fig. 1-c). The winters that had a large number of warm (cold) periods and a very small number of cold (warm) periods were selected as warm (cold) winters (Fig. 2).
Figure 4 shows the average precipitation rate and its ratio to normal values for the periods. In a warm winter relatively heavy precipitation (above normal) was observed over a broad area except the Japan Sea coast area, whereas in a cold winter the distribution showed the reverse pattern.
Synoptic factors bringing precipitation were classified by using daily synoptic charts (Table 1). Figure 6 shows these factors: 1) M-type, in which the pressure patterns are “West-high East-low” type and NW monsoon is strong, 2) L-type, in which extratropical cyclones are situated in the vicinity of Japan and the NW monsoon is very weak or absent, 3) ML-type, which means a transi-tional pattern from L-type to M-type, and 4) 0-type, which means “others” The occurrence fre-quency for the six winters (Table 2) shows that about 70% of total days were classified as days with M- and L-type precipitation.
Figures 7 and 8 show the precipitation amounts and percentage of total amount for each factor, respectively. M-type precipitation dominated the Japan Sea coast area, especially in the central part of Honshu Island; the percentage value exceeded 50% in cold winters, whereas it was about 20% in warm winters. L-type is the only main factor in the Pacific coast area, so this type showed about 80% in either warm or cold winters. In addition, L-type precipitation is fairly abundant in warm winters even in the Japan Sea coast area, and this became the dominant factor in warm winters almost all over Japan except in the central part of Honshu Island.
In sum, during warm winters most precipitation in the whole country was caused by extratro-pical cyclones, whereas in cold winters the NW monsoon caused a great deal of much precipitation and dominated in the Japan Sea coast area. The only area with above (below) normal precipitation in cold (warm) winters was the central part of the Japan Sea coast of Honshu, Island, because of the greater increase (decrease) in M-type precipitation than the decrease (increase) in L-type precipitation.

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大麦の凍霜害低抗性の品種間差異を明らかにしようとして，耐寒性の強いコウゲンムギと弱いみすず大麦を供試し，その生育各期に一5℃の低温定温器で6時間処理して，低温障害の差異を調査した。(1)低温による障害は著しく，生育を遅延させた。また，収量に影響甚しい時期は伸長期から穂孕期であった。(2)茎葉に及ぼす障害の程度は耐寒性の強いコウゲンムギに甚しく，弱いみすず大麦は軽微であった。(3)幼穂の凍死は幼穂長と関係し，幼穂長が6mm以上になると凍死するもの多く，5mm以下では少たかった。これはまた，桿長と密接に関係し，桿長が長く，幼穂が地表に現われやすくたるほど凍死率は高くたった。しかし，幼穂そのものの凍霜害低抗性の品種間差異は認めることができたかった。(4)凍霜害による幼穂の生死の判別にはLUYET氏溶液による染色が有効であることが明らかにされ，それによれば，幼穂の凍死には，(i)幼穂そのものが凍死する場合(ii)幼穂に続く幼桿数節が凍死し，二次的に幼穂も枯死する場合(iii)両者が凍死する場合以上の三段階のあることが判明した。

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1. この報告は昭和30年4月埼玉県所沢市附近に発生した小麦の凍害被害株に就て追跡調査したものである。
2. この凍害は従来, 北関東に発生の多かつた秋播型小麦の幼穂凍死とちがい, 春播型小麦の幼穂凍死であつて遅発茎の顕著な有効化と出穂遅延が特徴であつた。
3. 凍死を起した気温は4月5, 6両日の低温で, 本調査3圃場の枯死歩合 (推定) は「甚」68.3%,「中」48.1%,「軽」23.3%であつた。このような差を生じたのは作物の生育ステージのズレに主因すると思われる。
4. 凍害がその後の生育に及ぼした影響は, 遅発茎数, 稈長, 茎径, 出穂期などに著しくあらわれた。
5. 凍害の収量に及ぼす影響は上麦重歩合の低下, 屑麦重の増加, 千粒重の低下などである。「軽」では減収は見られず,「中」で3割,「甚」で7割の減収であつた。これは遅発茎の生産力の差異によるところが多い。
6. 春播型小麦の幼穂凍死による減収の把握を困難にするものは, 遅発茎の生産力の判定であるが, この生産力は出穂遅延日数, 稈長, 茎径と高い有意の相関がある。

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The purpose of this paper is to explain the distinctive features of the maximum snow depths in NIIGATA prefecture. The maximum snow depth data for the 'cold half' years from 1891 to 1987 were collected from the NIIGATA Local Meteorogical Observatory. The number of observatories keeping data is 60.
Concluding remarks are as follows :
(1) The deepest disturibution of maximum snow depth is determined by the difference in the height of the eastside or southside mountain chains. (Figs.1, 2, 3, 4)
(2) The shallowest disturibution of maximum snow depth is closely proportional to the height of each observatory. (Figs.1, 5)
(3) The heavy snow's patterns in NIIGATA prefecture are classified into two types : 1945 yr. and 1963yr. (Figs.6, 7, 8, 9)
(4) The upper limit of maximum snow depth which is estimated relative to an observatoty's height is shown by the following formula. (The upper limit line is designated "N-Line", Fig.10)
Hs=200 logH+75
Hs : the upper limit of maximum snow depth (cm)
H : the height of the observatory (m)
However, the maximum snow depths of two observatories, TAKADA and TOCHIOMATA, were over the N-Line.
(5) Taking into account the changes in the maximum snow depths after the latter term of the Meiji era, there seems to be two cycles of snowfalls : a cycle where there is a relatively little snowfall followed by a period of heavy snowfall and then repeating. (Fig.11)
(6) In the UONUMA area which has a heavy snowfall for NIIGATA prefecture, there are cycles of mild winters from 5-8 years. All mild winters are not the same as in El Nino years, but there is a possibility that a big El Nino brings a mild to average winter (relatively mild snowfall) to the UONUMA area. (Fig. 12)

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It seems for us to have more and more colder or warmer winters in these days. This Paper studied about the wind over sea near Japan in colder and warmer winters, respectively for Jan., Feb., of 1974 and 1977 and of 1969 and 1979. The difference and the characteristic of the wind speed between the two cases and their distributions were studied. Frictional coefficient, and unstable coefficient due to sea and air temperature difference were taken into account to calculate the wind speed, after getting gradient wind or geostrophic wind from weather charts. The observational wind speeds by ship were compared with the theoretical ones to check if they would coincide. The results are as follows. First, the maximum wind speed area is extending along 33°〜36°N of mid-latitude in colder winters. So, the other strong wind area is appeared near Japan as cyclones are apt to pass by it in warmer winters. Secondly, when Zonal Index is high, strong wind area is in the east from 160°E. When it is low, the area moves to west.

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・現象は、最寒期間の平均最低気温が、ある値(茨城県日立市では、ほぼO℃)以下にならないことを示した。・現象は1987年から始まった。・2005年までのデータによって、現象が始まると、次の5種が茨城県に侵入し2種が定着したことが確認された。種名 状況 侵入年クロコノマチョウ 定着 1993ムラサキツバメ 定着 2000ウスイロコノマチョウ 1990ツマグロヒョウモン 1地点定着1998ナガサキアゲハ 2000(幼虫)2004(成虫)・侵入した5種の分布は、暖地性植物分布境界線以南の地域である。・クロコノマチョウとムラサキツバメは、茨城県の太平洋岸北上回廊を経て、東北地方南部の太平洋岸(福島県浜通り)に侵入した。ムラサキツバメは、2001年に侵入していたことが確認された。

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近年の温暖化に伴い，九州などの暖地で，ニホンナシ露地栽培における発芽不良の発生が顕在化してきている．そこで本研究では，発芽不良の発生軽減が期待される春施肥の有効性を，‘豊水’ および ‘幸水’ において，5年間継続して検証した．両品種において，施肥時期を慣行の秋施肥から春施肥に変更することで，耐凍性が向上し，5年間安定して発芽不良の発生が軽減された．一方，9月と3月に分施する秋春施肥では，耐凍性の向上効果および発芽不良の軽減効果は見られなかった．なお，春施肥に変更したことによる果実品質への悪影響は認められなかった．以上のことから，凍害によるニホンナシの発芽不良発生の軽減策として，全量を春に施用する施肥法は，有効的かつ実用的なニホンナシ露地栽培技術であることが明らかになった．

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In order to reconstruct the winter climate in Japan in the 18th century, the authors tried to gather weather records of old diaries written in that period. The winter climate in Japan is influenced by the east high-west low pressure pattern and its severity is highly correlated with the frequency of the pressure pattern on a seasonally or monthly time scale. The weather distribution pattern under the west high-east low pressure type is characterized by the bad weather in Japan Sea Coast and fine one in Pacific Coast.
By the use of the character of the weather distribution pattern under the winter pressure, the frequencies of the typical winter days are interpreted from the weather distribution diagram made for the research period on a daily base from 1st November of the former year to the 31 st March of the year. The stations of the diaries gathered for the study are Hirosaki, Takada, Kanazawa, Sabae, Tottori and Hagi as Japan Sea Coast, Hachinohe, Morioka, Nikko, Kofu, Ise, Kyoto, Ikeda, Tsuyama and Usuki as inland or Pacific Coast.
The results obtained from the study are shown in Figure 1 as an annual number of the frequency of winter pressure days. On the same time scale, the freezing dates and the records of unusual weather in winter (cold or mild) are composed in the figure. The relationsbetween the frequency and other historical documents are investigated.
The secular changes of severity in winter were well coincided with the other weather proxies. The cold winter years can be found in the decades in the 1700s-1710s, the former 1730s, the 1750s and the former 1780s. The warmer winter years were in the decades in the 1720s, the 1740s, the 1770s, and the 1790s. Unusual severe winters recorded in the periods are not always identical to the frequency of the winter pressure days, because of its temporal or local effects.

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