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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Wilting of kidney bean leaves was examined after rainfall and after artificial rainfall (mist) in a growth chamber (20°C, 6 klux).
On rainy days, kidney bean leaves exposed to rainfall for 20 hours were wilted during the subsequent several hours.
Exposure to mist in the growth chamber caused wilting in kidney bean and sweet potato leaves. The degree of wilting was weak after 1-2 days of exposure to mist, but that after exposure to mist for 3 days or more was strong. The degree of wilting in all the plants reached their maxima one hour after the end of mist exposure irrespective of duration of exposure, and decreased gradually after that. The plants misted for 1-2 days recovered from leaf wilting after 3-4 hours, but those exposed to mist for 3 days or more still showed some weak wilting or waving of leaves even after 24 hours. The degree of wilting was greater in young leaves than in older ones.
Wetting of only the shoot by the exposure to mist had a similar effect on wilting as that when the vermiculite in the pot as well as the shoot was allowed to be wetted by the mist. The use of deionized water also had a similar effect. Therefore, the effect of mist is probably caused by wetting of the shoot (mainly, leaf), and not by the high moisture in the rhizosphere or by any substances contained in the tap water.
Transpiration of leaves after mist treatment increased markedly. Notingly, the greatest transpiration occurred during the first hour (without mist) after the end of mist treatment, and the transpiration rate in light was about 3 times higher than that of the non-misted leaves. The rate in darkness also had a similar tendency, but was somewhat lower.
Leaves of kidney bean and sweet potato detached from the misted plants had a higher drying rate than that of the non-misted leaves. After 24 hours at 20°C and 65-70% in relative humidity, the weight of the leaves detached from misted plants decreased to 10% of the initial weight, but 50% in the non-misted leaves. The following hypothesis may explain the wilting phenomenon occurring after rainfall.
The structure on the leaf surface is injured by wetting of rain water, and the permeability of water in the leaf is increased, so that transpiration is increased greatly. This increase of transpiration destroys the water balance between uptake by root and loss from leaf, and a water deficit occurs in leaf, resulting in the wilting of the leaves.

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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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