When the harvest of rice in the North-Eastern Japan is very poor, the harvest in the Western Japan often seems to become also poor, and similarly for good harvest. This may be considered to be caused by some macroscopic weather. Thus the distribution of air masses in summer is investigated and following results connected with rice-physiology are obtained.
In good harvest year, the ogasawara air mass (mT) prevails almost whole July and August, but in poor harvest year the Okhotsk air mass (mP) or the Siberian air mass (cP) prevails freaquently in summer which generally produces cold, cloudy and wet weather;
Owing to this bad weather the harvest o rice becomes poor not only in the North-Eastern Japan but also in the Western Japan. Therefore, in case that the poor harvest is forecasted in the North-East we should also be anxious about it in the West.

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There have been many researches on the yield of rice-crop from the agroclimatological view-point in Japan. But the yield of rice-crop is resulted from the sum total of all the influences of environments from the time of planting to harvesting, including the quality of the seed, the condition of the soil and the social condition.
For the analysis of the influences of environments, we have applied the similar method of factor analysis as that has been adopted in the medical studies for the data on the yield of rice, for both early and middle-season crops, that resulted from the rice-experiments in 20 agricultural experiment stations of Japan covering the period of 30 years from 1911 to 1940, and obtained the coefficient of the first and second factors shown in Tables 1 and 2.

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Temperature distributions on the northeastern slope in the Konosu Experiment Farm, which is very gently sloping, were investigated during the winter of 1948-49. Results obtained on the fine day were as follows:
1. The diurnal movement of temperature stratifications along the slope is shown in Fig. 1. Outgoing radiation from the soil in the evening took place first at the slope and therefore warm air masses were recognized above it. The cold air from the heigh ground flowed into the lower places by night and accumulated on the concave field as well as in front of buildings, and this is confirmed by Fig. 3, which shows horizontal distributions above the slope 2. The minimum temperature distribution at the height of 10cm above the ground was different from that at the height of 1 or 1.5m. These distributions are represented in Fig. 2.

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The author observed the diurnal change of the local air temperature distribution by the 4 portable-thermographs which were set at the rigde of the low spur slope of the mountain. (Fig. 1.) Some results, on the March 4, 1951, is shown in Fig. 2. As is well known, the lower station has the greater range than the higher, and the difference of the range of 4°C per 100m. The air temperature of the highest station ascends earlier than the lower station after the sunrise and descends more slowly before the sunset. This figure, however, can not show the change in detail, because the air temperature generally has the small fluctuations.
(1) So he estimated the differences of the small fluctuations in short time (6 minutes) within the observed small area within 95% reliability. (Fig. 3.) We can conclude that the fluctuations reach about 0.3°C before the sunrise, 0.4-0.5°C in the daytime, and about 0.2°C after the sunset. And the stronger the winds, smaller the fluctuations become.
(2) The nocturnal downslope winds have a cycle of 1.5-2.0hours, flowing with the speed of 3-4m/s and drop the air temperature usually 0.3-0.4°C in 30-40minutes or occationally about 2°C in 2hours.
(3) The changes of the lapse rate or the inversion rate of the air temperature in 24hours are shown in Fig. 4. Temperature decreases with elevation from about 1hour before the sunset, and the maximum of their rates reaches about 3°C/100m. The maximum inversion rate is about 2°C/100m before the sunrise.

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In the 1st report, the relations between the distributions of plants in this Forest and their micro-climatic environments were related.
In this report, the comparisons between inside and outside of this Forest are taken up. i.e.
Comparisons between the Forest and Nara city on temperature, humidity, precipitation, and temperature variations (Fig 1-3, Table 1-3), and the Forest and Wakakusa-Yama in summer, winter; they seemingly represent good examples of “forest-climate”.

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The microclimate of the Gun San type silkworm rearing room in which, warming with charcoal fire from the floor and watering the floor and walls, the worms of earlier stage were reared was as following:-
1) As to the room temperature, a constant temperature stage was shown after a temperature rising stag of 1.5-4hours from the closure of the door. The temperature difference between the high temperatur place and low place was always less than about 1.5°C when the both pores, suction and removal, were closed butt it reached about 4°C when the pores were opened.
2) As to the room humidity, there also were to stages, a rising and a constant. The rising stage was 1-2 hours. The humidity difference between wet place and dry place was less than 10% when the both pores, suction and removal, were closed, but it reached about 20% when the pores were opened.
3) The evaporation rate of the water was about 60-80% of normal room, and was larger at lower place than at higher place.
4) The concentration of CO₂-gas was at least 2-4 times as much as that of normal room (in normal room CO₂ was 0.07-0.15%).
5) NH₃-gas was 1.2-1.3 times that of normal room.
6) CO₂-gas and NH₃-gas were almost homogeneously distributed in the room.

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Several meteorological factors were investigated under the shelters sloped 30°, 50°and 90°to the ground to know the microclimatic conditions under a shelter made the vegetables rapidly grow in winter.
No remarkable differences of air temperature were observed among the 3 experimented kinds of sheltered plots and the control.
The earth temperature of a plot with a 30°inclined shelter was the highest till the middle of January, but later a plot with a 50°showed the highest earth temperature. The control plot showed always lower earth temperature than the sheltered plots. The differences of the earth temperature among those plots became gradually smaller after the middle of February.
The most appropriate slope of shelter to the ground was investigated to maintain the earth temperature effectively under the shelter.

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We observed the temperature of the silkwarm-rearing room, at Fukuoka Sericul-Experiment-Station from 11th to 12th May, 1951. The stage of silkworm in the room was third casting (sleeping) period. We observed the temperature of the room with thermo-junction. Observed points are distributed respectively at every one meter east to west, south to north, and floor to ceiling. East and west side walls of the room were boarded with timber planks adjoining the neighbouring rooms, by them, and north and south sides with the paper sliding doors (shoji) adjoining the corridor. There was a fireplace in the middle of the floor and an opening is situated in the middle of the ceiling of the room. We draw the vertical and horizontal mean daily temperature distribution map and the results observed are follows.
1. Warm air heated by the fire ascends upward nearly vertically.
2. Some parts of ascended warm air escape from the opening in the ceiling, but almost all parts of warm air move along the ceiling, and descend slowly along the walls.
3. Cold air flowed in from outsides through gaps of the paper sliding doors (shoji) descends and spreads on the floor.
4. As the cold air mixed with the warm air in the space one meter high the temperature variation was the greatest in this space.
5. Temperature in the upper part of the room was stable and uniform in all the clay time.
6. Therefore we must utilize these upper warmer and more stable space of the room in order to get good result in spring when the outer air temperature is lower than the optimum rearing temperature.

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The transition of field-temperature in the warmer district of Kyushu was measured in wheat cultivating season; and the results were shown in Table 1.
The surface-soil temperature in early summer seem too high for the crop growth.
The lasting low temperature that causes cold damage does not frequently occur in this district.
The plant cover influences the vertical distribution of temperature in May. (Fig. 1)
The relations between the temperature in the meteorological observation field and that in the cultivating field are approximately linear. (Table 2)
The daily-range decreasing index (p) of soil-temperature and thermal-diffusivity (a²) are shown in Table 3.

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1. In Japan, seeding of winter leguminous plants for green manure or forage use is practiced among rice plants as their after crops. Milk vetch (Astragalus sinicus L.) and common vetch (Vicia sativa L.) are used commonly for this purpose, as they have suited morphological properties for the early growth in such a dark place.
2. Readings of a photocell type solarimeter indicated about 10 per cent of the exterior solar radiation is reached on the ground surface among rice plants, at the end of September.
3. Daily variation of ground surface temperature and relative humidity ranged narrower among the plants than on the bare land.
4. At the end of September, it is favorable to the germination of the seeds broadcasted among the rice plants through the sufficient temperature and humidity maintained in the daytime, and they result similar green yield levels comparing to the bare land culture. But in November, it turn: worse especially about the temperature and their yield is extremely less than the bare land culture.

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[in Japanese]

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The author investigated the influence of wind speed at 1 meter height upon the temperature difference between 10cm and 150cm height, and it was made clear that the temperature difference decreases as the wind speed increases. (See Fig. 1 and Table 2).
These relation hold good during the daytime with a fine weather condition.

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The compensated thermojunction to remove the radiation error due to direct solar radiation without using a shield over the measuring portion in the case of microclimatic temperature measurment, was devised as follows;
In adition to usual type of measuring element J₁ and cold element J₂, as the diagram indicates other compensating elements named J₃ and J₄ are employed. All the elements except J₁ are set at a distance from the measuring portion so that the general microclimatic state should remain undisturbed. The compensating elements, being constructed in the same form as J₁, should be placed very closely each other, J₄, one of them having small radiation cover. Then J₃ and J₄ are in the same temperature and only J₃ receives the solar radiation, the E. M. F. between J₃ and J₄ is due to the rise of temperature by solar radiation. This compensates the E. M. F. introduced by similar solar radiation between J₁ and J₂, showing now only the air temperature of measuring portion, that is, J=J₁-J₂-(J₃-J₄). Testing examples on the lawn are shown in Fig. 2. In the Fig., (a) is the record by the new type compensated junction and (b) the record by usual thermojunction without radiation shield, (c) the record of F. M. F. on a pair of same shaped thermocouples, only one of them screened, (d) the wind velocity measured by hot-wire anemometer and (e) the solar energy by Gorczinsky's solarimeter. These experiments show clearly the advantage of the new apparatus. Applying this method the temperature of leaf surface or skin temperature of human body under direct sunshine can be measured without disturbing the natural state.

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We measured the absolute humidity by a thermo-couple circuit, which converts the variation of humidity in to the variation of the reading of galvanometer in directly proportional relation.
The measured value of humidity by our method shows a fairly good agreement with the measured value by Assmann psychrometer.
The time lag of our method is much smaller than that of Assmann psychrometer.
When the difference between the standard temperature and the wet-bulb temperature reaches a large value, the measurement does not show the true value of humidity.
This method has some advantages over other methods to record, the rapidly changing humidity with precision.

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The present experiment is a part of studies as for the quantity of irrigating water for the rice field in the warmer district of Kyushu.
The results shown in Table 2 are the typical, values on a clear day at the maximum tillering stage of rice.
1) The absorption of water by the plant is vigorous in the forenoon, decreases rapiddly in the afternoon, and almost ceases in the early night. It recovers gradually in the dead of night.
2) The evaporation from water-surface in the field is about 45% of that measured with the evaporation-gauge of “Japanease Meteorological Observatory Type.”
3) The percolation is dependent on the topography, sort of soil, climate and the depth of groundwater-surface.
Much attention should be paid as for the percolation, for it is very large and variable in each locality.

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We observed the max. and min. air temperature of 38 observation-points at Aoki village, Nagano Prefecture. The results obtained are as follow.
(1) The min. temperature is higher at the high place than at the low place, but (2) the max. temperature distributes complicately and is mush influenced by inclination, duration, and etc.
(3) Then we found from the records of thermographs a fact that courses of diurnal change of air temperature at the different places were various.

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The author deals with the effect of wind shelter both theoretically and experimentally, making use of aerodynamical results according to the modern similarity theory of turbulence.
The geometrical and dynamical characteristics of the effective zone of shelter-hedge where the wind velocity is diminished are discussed theoretically by means of knowledges concerning the structure of wind near the ground, i. e., the logarithmic velocity distribution U(z), the vertical distribution of life-time of the largest vertical turbulon τ₀(z) and the roughness parameter Z₀ of the ground surface. Thus the characteristic length L of effective zone of the shelter-hedge of the height h is obtained approximately in terms of parameters mentioned above as
L-U (h) τ₀ (h)
-h log (h/Z₀)
and is further deduced to be in proportion to h8/7 provided the logarithmic law of velocity distribution might be substituted by the 1/7 power law such as U(z)-U_c (Z/c)1/7 where c and U_c means a certain characteristic height and the wind velocity at that height.
These theoretical results, indicating the influences of both hedge height and roughness parameter on the length of effective zone, are examined experimentally in the wind tunnel with good results, where the turbulent boundary layer is artificially set up with roughness of several types.

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The amount of evaporation in a large size evaporation pan is measured by reading the level of the water surface with a hook gage. In the sun, however, the water surface level varies with the change of water temperature. Then, the diurnal change of evaporation can not be measured by the leveling method with the hook gage.
The authors have designed and constructed the differential evaporation recorder with which the change in level owing to temperature variation is cancelled and that owing only to evaporation is recorded. The instrument consists of three parts: two floats, a differential mechanism with a pair of pulley and a string, and a tappering recorder. As shown in Fig. 1, one float (F₁) moves vertically in response to the changes in level of the water owing to both of evaporation and expansion, and the other (F₂) floating on the oil covered surface in the small cylinder (C) responds to the changes in level owing to the expansion and contraction of the water. The motion of two floats is each converted into the motion of the pulleys (P₁, P₂) by the levers, and the difference of two vertical motions of the pulleys is transmitted to the terminal of the pen-arm by the string (f).
The pen is kept a little apart from a recording drum and pushed against the drum once a minute by tapper-bar driven by a synchronous motor.
This instrument can record the amount of evaporation in the precision of 0.1mm. Photo. 1 shows a example of the records, from which calculated intensity of evaporation is illustrated in Fig. 3 with the diurnal variation of other weather factors.

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They say that the going up of water temperature by 1°C increases yield of rice by 15kg per 1ha in the cold part of Japan. The windbreak is said th be effective for this purpose and now partly used, but its effect is not yet clear quantatively. Author and his co-workers observed this point on Aug. 1950 and 51 on the field shown in Fig. 1. The two main results are as follows:
1) The two basins of stagnant water which are influenced by air temperature a day long in and off wind-break, have the difference of temperature in daytime as shown in Fig. 2. In the Fig. 2, the X axis is insolation, the Y axis is mean wind velocity during one hour before each observations. In this case, the temperature of water layers at 1cm and 10cm from the bottom, show little difference between them.
2) The two basins of cold water which are lower 10°C than air temperature, go up with the difference of about 1°C between the basin off windbreak and basin in windbreak in the case of little insolation or in nigh. The results are shown in Tab. 1. In this case, the water layer at 1cm from the bottom is 2°C cooler than 10cm in windbreak and 1.6°C off windbreak, i. e. the windbreak shows negative effect. The case of daytime is not yet concluded.

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In Hokkaido, the yield of rice-crop is influenced more by the natural environmental condition than by the social condition, as the place is situated in the border region of rice culture. Human efforts in rice culture over there had been often vainly consumed in the past cool summers.
When we try a factor analysis for the rice-yield in such a region, it is not so difficult problem to know what factors are more concerned with the region than with the other parts of Japan. We adopted a factor analysis for the rice-yields of 12 districts in Hokkaido covering the period of 35 years and obtained a factor load diagram as shown in Table 1.

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In the first report of this investigations the author pointed out that the normal thermal diffusibility of the paddy field increases monotonously with the increase of percolation.
In this report, the auther shows how the water temperature in a paddy field undergoes a change if the water is continuously supplied as the percolation goes on.
For this purpose, 2 different lysimeters were specially constructed, one in an open field, and the other in the laboratory where illumination and temperature are controllable.
1. The vertical distribution of temperatures of the water in the paddy field which was irrigated by warm or cold water through a watering inlet at the corner of the field was investigated, and the manner of inflow or diffusion of water was come to light.
The temperatures distributed uniformly from at the distance about a quarter of the diagonel.
2. The horizontal distribution of temperatures is much more regular than the vertical and the isothermal lines are nearly a series of ellipses with their center at the inlet of irrigation water and the eccentricity increases with increasing percolation and it gets uniform at the distance of a quarter of the diagonal.
3. From the above results, the center of the paddy field may be regarded approximately as the thermal center of the field.
The relation between the temperature θ_* of the thermal center, the amount of percolation water and the temperature of the supplying water can be expressed by
θ_*=A₀s{1-exp(-p)}^0.004+ΣA_nexp(-p)^-0.12+0.436ssin(2nπ/Tt+ε_n)
and the water temperature of the paddy field, if the water does not leak, is
θ=A₀+ΣA_nsin(2nπ/Tt+ε_n)
where s=The temp. of irrigation water—The mean temp. of the paddy field without percolation./The amplitude of temperature variation of water of the paddy field without percolation water.
p=The amount of percolation water.
The above fact shows that the water temperature of the percolating paddy field depends not only upon the amount of percolation water but on the temperature of the supplying water.

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Two theodolites were used with a base line 50m long to measure the height of hovering skylarks (Alauda arvensis japonica Temm et Schl), June 11-27, 1951 almost exclusively in the afternoon, in an open field near Tokyo.
The skylark usually remain, in the sky flying at the level of 80-100m (see fig. 2) discribing a nearly horizontal circular path of a diameter about 60m lore.
The heights are not seemingly affected by any meteorological element-temperature, wind etc, -so long as the temperature ranges from 20 to 28°C and the wind velocity is within 5m/sec (fig. 3).
However the same bird is found flying at a height scarcely exceeding 20 m high, in the Kuril Islands.
It is too low in altitude to attribute it to the different variety of Alauda arvensis and such low altitude may be owing to the intense coldness of the locality. So some climatic element seem to control the hovering height to a certain extent.

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