Meteorological Fluctuations Research Articles

Studies on Meteorological Fluctuation in the Growth of Rice Plants : IV. Factors Affecting Duration from Sowing to Heading under Different Temperature Levels ad Sowing Times.

Heading tirne of rice varieties are known to be controlled by three factors, thermo-sensitivity(X1)' photo-sensitivity(X2) and basic vegetative growth(X3)' Degree of contribution of the three Lactors to the determination of growth duration from sowing to' heading was investigated. In the first experiment, 44 rice varieties were grown in a growth cabinet, the temper-ature of which was controlled so as to give a constant difference from the temperature of the open air. The measure of the three factors was obtained by growing plants in a growth cabinet with short(S:10h) or long(L:14h) daylength and low(L:20'C) or high(H:30'C) temperature. X1, X2 and X3 are expressed by nSL-nSH, nLL-nSL and nSH, respectively, where nSL Stands for the number of days from sowing to heading in case of 10h and 20'C, and so on. Multiple correlation between growth duration(Y) and a set of X1, X2 and X3 was. highly significant in all temperature levels, showing that the most part of varietal diffe-rences in growth duration can be explained by the three factors in combination. The standard partial regression coeffcient of Y on X1, X2 and X3 revealed that photo-sensiti-vity(X2) is most important in determining growth duration, followed by basic vegetative growth(X3), thermo-sensitivity(X1) showing no influence.

Variability of local demands as the framework for future energy planning

Long term planning of energy demands may be impossible without in-depth consideration of factors found at present to be of little importance. We have undertaken a pilot survey of energy demand fluctuations in North West England in an attempt to identify factors which at present cause slight perturbations in the demand patterns but which may, in the future, become more relevant. Our results suggest that, as well as the known factors (ie industrial to domestic consumer ratio and regional temperature) other parameters, particularly socio-economic status, population and building density and possibly even secondary meteorological fluctuations affect the energy demand curves. National policies which will alter energy demand (ie encouragement of alternative technologies, pricing policies, industrial and population resiting) must take into consideration the increasing influence of the factors identified here.

Observations Of Glacier Seismicity On Unteraargletscher

Abstract Almost continuous recordings of glacier seismicity were obtained on Unteraar-gletscher (Berner Oberland, Switzerland) over a period of two weeks at the end of May 1977. The seismograph array consisted of micro-earthquake recorders, some recording directly onto smoked paper (three Sprengnether model MEQ-800) and others recording onto magnetic tape (one MARS-72 apparatus and two seismic-event recorders). The frequency range covered by the instruments lies between 1 and 85 Hz. The array spanned a relatively crevasse-free area of about 500 m by 700 m. At the beginning of the period of observation only a few events were recorded per hour. Probably as a consequence of increased run-off of melt and rain, which acted as a lubricant or as an agent of hydraulic fracturing within or beneath the glacier, the activity rose in two days to a maximum of 120 events in one hour, and then with minor fluctuations it gradually decreased again to its initial level. The variations in activity showed signs of correlating with the velocity measurements, which however were only started after the main maximum, but did not seem to be influenced by the uplift of the glacier surface or by the diurnal meteorological fluctuations. Most of the recorded signals could be classified according to their frequency content into three groups: 40, 20, and 5 Hz. The 40 Hz events, whose duration was less than 1 s, are located near the glacier surface and probably correspond to those attributed by Neave and Savage (1970) to the formation of crevasses. The majority of the events were of the 20 Hz type, each of about 1 s duration. Due to inadequacies in the seismometer array, only three of them could be located with sufficient accuracy: they originated in different areas of the glacier at a depth of about 150 m, which is strong evidence that icequakes are not, as previously thought, limited to the upper 40 m. The signals of the 5 Hz type, lasting several seconds, are thought to be 20 Hz events whose higher frequencies have been attenuated by a longer travel path. The lower-frequency signals from the glacier bed, reported by Bindschadler (unpublished) and by Weaver and Malone (1979), were not observed. This could indicate that a variety of mechanisms are operative at different times of year. In particular, the subglacial conduits were only poorly developed in Unteraargletscher at the time of these recordings.

Une synthèse provisoire : les vendanges du XVe au XIXe siècle

Les fluctuations météorologiques du XVIe siècle ont déjà fait l'objet de divers travaux. Pour une élucidation systématique de celles-ci, les méthodes fondées sur la phenologie et notamment sur l'étude des dates de vendanges demeurent d'un intérêt capital. Nous nous bornons à rappeler brièvement, à ce propos, des faits bien connus : toutes choses égales d'ailleurs, les dates de vendanges tardives sont révélatrices d'une période de végétation de la vigne (mars-avril à septembre-octobre) au cours de laquelle les températures, en moyenne, ont été plutôt froides. Les vendanges précoces, au contraire, indiquent, pendant le même intervalle saisonnier (printemps-été), des moyennes thermiques relativement hautes. Les fluctuations thermométriques se lisent donc de façon grossièrement approximative, mais indubitable sur la courbe des dates de récolte du raisin.

Effects of atmospheric turbulence on the interference of sound waves near a hard boundary

The mean sound levels resulting from the interference between direct waves and those reflected from the ground are strongly influenced, especially at frequencies near interference minima, by fluctuations in phase and amplitude of the sound waves induced by propagation through atmospheric turbulence. Since it was found experimentally that the correlation length (∠1.1 m) of the meteorological fluctuations is comparable to the separation between the interfering sound paths, previous theoretical work by Ingard and Maling [J. Acoust. Soc. Am. 35, 1056–1058 (1963)] has been extended to allow for partial covariance between the two waves. The theory has been further extended to use the calculations of fluctuations in phase and amplitude of spherical waves, and to include the explicit calculation of the fluctuating acoustical index of refraction from the fluctuating values of temperature and wind velocity. Measurements (1–6 kHz) have been made of the interference spectrum at 15, 30, and 45 m from a point source 1.2 m above a large asphalt surface. Simultaneously, the fluctuating values of temperature and horizontal wind velocity (atmospheric turbulence) were measured at two related points close to the sound path. There is satisfactory quantitative agreement between the sound levels calculated from the measured fluctuating meteorological variables (with one adjustable parameter) and those measured experimentally.

Studies on Meteorological Fluctuation of the Growth of Paddy Rice Plants : II. Difference of the thermo-response in heading of varieties between in rice culture using young seedling and in rice culture using mature seedling (Japonica)

Difference of the thermo-response of heading date, number of main culm leaves and leaf emergence intervals between the culture using mature seedling (5th leaf stage) and the culture using young seedling (2nd leaf stage) have been investigated with 36 paddy rice cultivers of various maturities under five different levels of temperature in semi-open air controlling cabinets. Air temperature in the rice community in the cabinets were kept at 3°C, 1.5°C and 0°C warmer, and 1.5°C and 3°C cooler than that of the open air as an average during rice cultivated period in Morioka (Iwate) in 1974 (Fig. 5). The heading response in varieties to the temperature in culture using mature seedling and that using young seedling were explained in terms of number of main culm leaves and leaf emergence intervals in the following way. 1. The difference of leaf age in varieties among each thermo-condition was larger in culture using young seedling than in culture using mature seedling (Fig. 4), and the response of total leaf number on main culm of varieties to temperatures was a little higher in culture using young seedling than in culture using mature seedling (Table 3). In consequence, the fluctuation in heading of varieties by temperature was larger in culture using young seedling than in culture using mature seedling (Fig. 1). 2. The difference of total leaf number between two cultural methods was larger in late varieties than in early varieties, and was larger under high temperature than low temperature (Table 3). The difference of leaf age of varieties between two culture methods was a little larger under low temperature than under high temperature (Fig. 4). From these results, the difference of heading date between two culture methods was larger in early varieties than in late varieties, and was larger low temperature than under high temperature (Table 1, Fig. 5). From these facts, it can be said that the risk of cool weather damage increase futher in rice culture using young seedling.

Studies on meteorological fluctuation on the growth of rice plants.: I.Varietal differences of the heading response to temperature in paddy rice plants

Varietal responses of heading date, number of main culm leaves and leaf emergence interval have been investigated with 48 paddy rice cultivars differing date of maturity under five different levels of temperature using semi-open air controlling cabinets. Early maturing varieties tend to be more sensitive to temperature in heading and late ones show less sensitivety. But the relative order of heading date among varieties is rather stable and little disturbed by temperature treatments. Varietal responses to temperature in heading are explained in terms of number of main culm leaves and leaf emergence intervals in the following way. 1) When early maturing varieties are grown urLder warm condition, the leaf extension is accelerated and leaf emergcrence intervals are remarkably shortened. Also number of main culm leaves decreases under high temperature. They have large variability in heading: date under different air temperatures. 2) The situation is different in late maturing varieties. When they are grown under warm environment, the leaf emergence intervals are shortened on one hand, but numberof main culm leaves increases on the other hand. On the contrary late maturing varieties, grown under cool enviromrrent are slow in extending leaves but develop smaller number of leaves. In consequence late maturing varietis are less variable in heading date under various temperature conditions.

A Study in Meteorological and Trade Cycle History: The Economic Crisis Following the Napoleonic Wars

The factors regulating the production and distribution of material wealth cannot be reduced exclusively to market relationships. This being the case, the economic historian cannot limit his borrowings to economics alone. The present article uses meteorology both in its theoretical and historical dimensions to show the interaction between economic and meteorological fluctuations. The attempt of W. S. Jevons to find a theoretical connection between solar cycles and trade cycles is well known. Economic historians of preindustrial Europe have identified weather patterns as a primary independent variable determining prosperity or depression. The impact of meteorological fluctuation on economic activity has also been noticed for the nineteenth century, acknowledged by theorist and historian alike as one of the major variables inducing trade cycles. But in these accounts weather patterns are introduced as a run of good or bad luck, affecting essentially regional or national economies.

Insensitivity of subtropical mode water characteristics to meteorological fluctuations

A striking feature of subtropical mode water (‘18° water’ in the North Atlantic) is the lack of change in its temperature and salinity despite exposure to the atmosphere under varying winter conditions. A local, one-dimensional model is developed for the determination of mode water characteristics, which agrees well with observations for mean conditions, in both the North Atlantic and the North Pacific. The model is then used to estimate effects of reasonable weather fluctuations, and it is found that the expected temperature and salinity changes lie within their small observed ranges of variation. Because of the great thickness of the mode water layer, and the brief time actually available in any one winter to modify it, winters would have to be very much more severe than really occur to make any great change in its characteristics.

The Nature of the Meteorological Fluctuations in Clouds

Abstract As in-cloud measurements have accumulated it has become increasingly apparent that clouds are markedly non-uniform in structure. This is demonstrated by sizable and rapid variations in the horizontal for almost all meteorological variables. A systematic study was made of the fluctuations in measurements obtained in hurricane clouds to establish whether they could be ascribed to a random process or whether they exhibited some spatial order. Variance spectrum analysis of continuous measurements of temperature, liquid-water content and air-speed for 49 cloud areas indicated that, in most cases, the variations were not random and that, in addition to the cloud scale, there were non-random components of smaller size. With considerable consistency, particularly in turbulent convection, the spectra indicated the existence of two frequency “domains” within which one or more dominant modes of activity occurred. These domains extended a) from 1.8–4 cycle mile−1 with peaks most frequent around 2.5 cycle mil...

Radioisotopes P32, Be7, and S35in the atmosphere

We have made simultaneous determinations of the concentrations of the radioisotopes P32, Be7, and S35 in several rains collected at Bombay during the monsoon period of 1958. The observed annual deposition rates of P32 and Be7 are found to agree within the expected meteorological fluctuations with those measured in the preceding two years at Bombay and other stations in India. S35 deposition, however, has varied significantly outside normal fluctuations. From the observed variations in the annual fallout of these isotopes during 1956–1958 and relative isotope concentrations in individual rains, it has been concluded that nuclear weapons have not resulted in any appreciable contributions to the observed Be7 and P32 activities. However, S35 was contributed in appreciable quantities. During 1958, S35 concentrations were very large, amounting to as much as 35 per cent of the observed Sr89 concentrations in some rains. The relative concentrations of the isotopes Be7 and P32 in rains vary in a manner that would be expected for their production in the troposphere by cosmic rays, and their removal by wet precipitation with an average removal period of about 40 days. None of the rain samples analyzed so far could have resulted in precipitation occurring from an air mass which descended in the troposphere after an irradiation in the stratosphere for time periods that are long compared with the half-lives of the isotopes.