Climatic features of air temperature are generally described in terms of the average and extremes for a finite time interval. But the modeling of the time distribution of air temperature has not been paid much attention. We proposed some local climatic indices which were defined on the basis of the air temperature frequency distribution for a 5-day period (a pentad) and set up a pentad distribution model (CND model) in the first paper of this series of studies. In the present paper the accuracy of reconstructing the time distribution of air temperature from the local climatic indices by the use of the CND model is discussed. An example of the application of the reconstructed distribution to a local climatic temperature analysis is also given.
The accuracy of the reconstruction was examined by comparing the quartiles of monthly air temperature distribution derived from the reconstructed distribution with those from hourly temperatures. The result is that the reconstructed distribution is not biased but its wings are truncated to some extent, the interquartile range being on the average about 0.4°C too short. The numbers of hours within various temperature limits computed from the reconstructed distribution were also compared with the observed ones. The numbers of hours with temperatures, for example, below 5°C, above 15°C and 25°C in a year have been estimated with the accuracy of -0.6%, 0.7% and -1.3%, respectively.
The reconstructed air temperature distribution was applied to evaluate the difference in the surface water temperature of the northwest waters (1, 689ha), which will be drained near future, of Lake Nakaumi between before and after the construction of closing dikes. The local difference in the reconstructed monthly air temperature distribution in and around the shore area was found to reflect the change in the surface water temperature. The interannual changes in the local difference show that the completion of the closing dikes intercepting the inflow of fresh water at a relatively low temperature could raised the surface water temperature of this area by 1 to 2°C.

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The north-west district (Heilungjiang-sheng, Kirin-sheng and Liaoning-sheng) of China covers a wide region, approximately 3.3 times of the total area of Japan, and comprise various types of geographical features. As a result the difference in climatic conditions are considerable.
Thus, a multidimensional time series analysis is useful for the clarification of the distribution patterns of climatic elements and their fluctuations.
In this paper, the monthly data of air temperature and air pressure at 35 sites from 1961 through to 1978, were used for the principal component analysis. The principle patterns of air temperature distribution were obtained from the scattering diagram of eigenvector of each component.
The changeability and periodicity of principle pattern were clarified from the time series of scores of each principal component and its spectral analysis.
The results of principal component analysis of air pressure were used to trace the principle patterns of air temperature to its origin.
The results obtained are summarized as follows:
(i) The first three components can explain more than 80% of the cumulative variance. The spacial eigenvector patterns are shown in Fig. 2. The first component (73.0% of total variance) represents “over the entire area” or “cool over the entire area” patterns of monthly air temperature distribution. The second component (11.4% of total variance), consists of the “east hot—west cool”or“east cool—west hot” patterns.
(ii) The prevailing patterns of air temperature distribution change from year to year and the aspects of the change are different for each month as shown in Fig. 5. For example, the prevailing patterns in summer (July) are “cool over the entire area” pattern in 1961-1966, “north hot—south cool” in 1967-1970, and “hot over the entire area and north hot—south cool” patterns in 1971-1978.
The spectrum analysis of the first and second components for July showed that these two components have the periodicity of 5-6 years and 4-5 years, respectively. From the same analysis for monthly data of the first and second components, it was clarified that these components have a periodicity of 36 months.
(iii) Using the values of the first component, the five patterns of monthly air temperature distribution in the north-east district in China were classified as very hot month (A), slightly hot month (A_B), normal month (C), slightly cool month (B_A) and very cool month (B). The frequency of the hot months (A+A_B), normal months (C) and cool months (B+B_A) were 32%, 40% and 28%, respectively.

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降雨後, インゲンマメ葉が萎凋する現象がみられた。降雨後の萎凋現象について解明するため, 人工降雨実験装置を使って, その萎凋現象の実態と原因について実験的に検討を行った。
1) 雨の日, 鉢植したインゲンマメを屋外におき, 降雨を21時間受けた後に葉が萎する現象がみられた。萎凋の状態は, 葉縁が上方に曲り, 葉全体がいくらか杯状を呈し, 極端な場合は葉縁付近の裏面が表面から見える程度にまき上る状態になった。
2) 雨の日を想定した人工降雨装置を使って, 降雨処理後の萎凋現象の実態を詳細に検討した。降雨処理した植物の葉は, 処理終了後15分位から萎れ始め, 1時間目に最高の萎凋程度に達し, その後数時間かけて回復した。萎凋程度は処理期間が長い程強く現われ, またその回復も遅くなる傾向がみられた。またサツマイモ葉でもほぼ類似の萎凋現象がみられた。インゲンマメ葉の場合, 1～2日間の降雨処理では, 程度の弱い萎凋がみられ, 3～4時間後にはほとんど回復したが, 3日以上の処理では強い萎凋現象がみられ, 処理後24時間目でも葉縁に多少の異常が残った。また若令葉ほど, 老令葉と比して, 萎凋の程度が大きい傾向がみられた。
3) 降雨処理後の萎凋現象は, 地下部への雨の浸入が遮断された場合, 逆に地下部を浸水状態にして降雨処理した場合でも, あるいはイオン交換水で降雨処理した場合でも, 同じ程度に起こることから, 地下部の状態や水道水中の諸成分に関係なく, 雨水が地上部 (葉) を濡らすことによって起こると考えられた。
4) 降雨処理後における葉の蒸散量は急激に増大した。処理後1時間目の蒸散量は11.5mg/cm²であり, 無処理区の4mg/cm²の約3倍の値を示した。この1時間における降雨区の根による吸水量は5.2mg/cm²であり, 蒸散による水の排出は根による水の吸収の約2倍の値であった。
5) 降雨処理された植物から切離された葉の乾燥速度は無処理区のものよりも著しく大きい値を示した。無処理区の植物からの切葉は1日後, 切断時の生鮮重の約50%まで減少した程度であったが, 降雨処理した場合は約10%まで減少した。
6) 上述のような結果から, 降雨後の萎凋現象の原因は, 地上部の雨水接触によって, 葉の表面構造に障害をうけ, 水の透水性を増し, その結果, 蒸散作用が急激に増大したことによると推察された。

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Thermal stress on dairy cattle is induced not only by high ambient air temperature but also by radiant heat gain. In an open-type barn, the inside air temperature can be decreased as low as the outside air temperature by improving air change rate through openings. The radiant heat inside a barn, however, results from a high temperature of surrounding roofs and walls, therefore be controlled only by changing roof or wall thermal characteristics.
Thermal environment in two types of dairy barns (A) and (B) was experimentally investigated. The thermal resistance evaluated between the inside and the outside roof surfaces was 0.8m2h°C/kcal for (A) barn and 0.005m2h°C/kcal for (B). In the clear summer daytime the inside roof surface temperature of (B) barn was dominantly high, and this caused the amount of longwave radiant heat from the inside roof surface 7 times as large as that in (A) barn. Heat transmission through the roof in (B) was also 5-8 times as large as in (A). As being predicted from largeness of the openings, the inside air temperature was within 2°C higher than the outside in both barns.
Two simple methods to reduce inside radiant heat were examined in (B) barn. They are 1) extending thermal-radiation-reflective aluminized film under the roof and 2) evaporative cooling of the roof due to watering on the outside surface. The aluminized film method did not decrease the inside roof surface temperature, but produced a nearly null value of the net radiation exchange inside. The watering method decreased both the inside roof surface temperature and the radiant heat down to the same level as observed in (A) barn.
The effect of reducing radiant heat load on the thermal regime of cattle was evaluated by measuring hair temperature. During cyclic watering on the roof of (B) barn, the change of the hair temperature was closely related to the change of the inside roof surface temperature. As the roof temperature dropped by 15°C according to watering, the hair temperature decreased by 2-3°C.
Equations based on energy flow through a roof were computed to predict the relationship between the degree of radiant heat load and roof thermal characteristics. In the computation the temperature difference between the inside roof surface and the inside air was used as a measure of radiant heat load instead of the actual amount of radiation exchange. The temperature difference increased almost linearly as the absorbed solar radiation of the roof increased, but decreased rather hyperbolically as the roof thermal resistance became large. The temperature difference changed to a considerable extent in the range of the thermal resistance from 0.01 to 1m²h°C/kcal. Out of this range the change of the temperature difference was not significant. Without watering on the roof, thermal resistance of 1m²h°C/kcal was obtained as a design value for reducing radiant heat load when the outside roof surface had the absorptivity to solar radiation as large as 0.8. Half the value of absorptivity reduced the design value of the thermal resistance by one-tenth. Watering on the roof reduced these design values significantly. The water requirement for evaporative cooling was not more than the amount of evaporation equivalent to solar heat gain.

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Albedo is an important factor which is related to the radiant and thermal environments. There are many works on the observation of albedo on various crop surfaces, and some literatures indicate that the albedo is affected by soil moisture, leaf area and so on. However, these results have not been determined quantitatively. It is the purpose of this paper to present the relationships among albedo and soil moisture, leaf area and weather condition on a potato field quantitatively.
The albedo on the potato field was related with the ratio of green canopy area (i.e. percentage of the area covered with green canopy to the total field area), the weather condition and the wetness of soil surface. In this paper, the dry spell days was used to describe the moisture condition on the soil surface, and the weather condition was represented by the extraterrestrial radiation ratio (i.e, ratio of solar radiation on the field to extraterrestrial solar radiation). The dry spell days is the number of days after the rainy day which has more than 15mm of rainfall. In case of less than 15mm of rainfall, the dry spell days was decided by using the relation between the wetness of soil surface and the dry spell days which was obtained in case of more than 15mm of rainfall in advance.
Calculation of albedo from daily totals of imcoming and reflected solar radiation indicated a range of 9% over wet soil to 12% over dry soil, and up to 21% over crop surface. At early growing season, the albedo was affected considerably by both the ratio of green canopy area and the dry spell days. However, the albedo at latter growing season which was more than 60 percent of the ratio of green canopy area, was not almost affected by the dry spell days. The effect of extraterrestrial radiation ratio on albedo was not significant all over the experimental period.
The equations to estimate albedo were drived by using both statistical method and another method. These equations need the values of ratio of green canopy area, dry spell days and extraterrestrial radiation ratio. The statistical equation, Eq. (2), brought about reasonable results on the estimation of albedo, but the behavior of expected albedo from Eq. (2) did not correspond with the real behavior when the ratio of green canopy area became larger. On the contrary, another equation, Eq. (8), suggested that it will bring about close agreement between both estimated and measured albedos under the condition of all ratio of green canopy area.

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In order to study turbulence characteristics related to sensible heat transports within and above plant canopies, the observations were made within and above wheat crops. The mean height of canopy was about 100cm. The results obtained at two heights (110cm and 35cm) during 1200-1700 JST on June 1, 1982 are summarized as follows:
1) Vertical fluxes of sensible heat at 100cm and 35cm were upward. They showed remarkably large variations, reflecting variabilities of solar radiation. Sensible heat fluxes at 35cm were smaller than one fifth of those at 110cm.
2) The standard deviations (σ_T) of air temperature at 110cm and 35cm were almost same and varied in the range of 0.5 and 2.0°C, corresponding to variations of solar radiation.
3) The skewness factors (S_T) of air temperature at 110cm were all positive but 4/5 of those at 35cm were negative. The flatness factors (F_T) at 110cm and 35cm fluctuated around the value 3 expected in the normal distribution.
4) The standard deviations (σ_w) of vertical wind velocity at 35cm were about 1/4 of those at 110cm. The skewness factors (S_w) were negative at both the heights, with remarkably large negative values at 35cm. The flatness factors (F_w) at 110cm were 3-5 but those at 35cm had greater values of 5-13. These results illustrate as shown in a previous paper (Maitani and Seo, 1983) that downdrafts penetrate intermittently in the lowest parts of wheat field.
5) The correlation coefficients r_wT at 35cm were about 0.2 and halves of those at 110cm. The correlation coefficients r_w110⋅w35 were almost constant (=0.4) but the correlation coefficients r_T110⋅T35 varied in the range of 0.2 and 0.7.
6) Joint probability densities (w-T or w-wT) at both heights had similar distributions. Downdrafts were more efficient for upward heat flux than updrafts at the heights of 110cm and 35cm.
7) The vertical fluxes wT² of temperature variance at 35cm were downward and the fluxes were divegent from the air layer between 110cm and 35cm.
8) The vertical fluxes wwT of covariance wT at both heights were downward and the fluxes were convergent into the air layer between 110cm and 35cm.
9) The peak frequency of the cospectrum nCo_wT (n) between w and T within plant canopies was lower than that above plant canopy. This trend was also seen in the power spectra of w and T.

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