bluuebunny/crossref_metadata_2025_split huggingface dataset:
Report on the phenological observations in the british isles from december, 1930, to november, 1931. no. 41
Authors: Clark J. Edmund , Margary Ivan D. , Marshall Richard , Cave C. J. P. 
Published: July 2010

Abstract1931 was officially described as “wet and dull,” the emphasis is on the latter; yet it was the tenth successive year with excess of rain, the total being that of eleven average years. A new table gives for each of the thirteen districts the number of weeks showing “decided” and “excessive” divergences from the averages for temperature, rainfall and sunshine. Out of the 572 events thus possible for sunshine during the spring and summer months there were only five decidedly bright against 72 dull. December, 1930, and November, 1931 alone were much on the warm side; March and September were cold. There were no records of “excessive” warmth in spring and summer, but 12 of “cold.” Such short cold spells in spring threw the flower records back half a week, and although migrants reached our coasts to date, their progress inland was belated. Fig. 4, with its areas of earliness and lateness in flowering, shows only small and scattered cases of the former— covering but one‐tenth of our islands. Nearly half lay in northwest Ireland, with four days early, whilst Dartmoor fell 20 days behind its natural lateness. Slugs and weeds, as might be expected, caused exceptional trouble. Fig. 6a, showing the average advance of migrant arrivals for 16 years, adds to the value of the associated tables.Thanks to a second broadcast in March, 1931, the corps of observers slightly exceeded 600. More would be specially welcome in west Ireland and north Scotland. The tables are based on more than 17,000 records.
The apparent colour of lights at night; with an observation of “blue fog”
Authors: Middleton W. E. Knowles , Patterson J. 
Published: July 2010

AbstractOn the basis of the CLE. (1931) colour metric an expression is developed for the colour co‐ordinates and luminosity of a given light source seen at night through an atmosphere of known optical properties. This is applied to an observation on a mercury vapour lamp in a highly selective haze of the type sometimes called “blue fog”.
The dynamics of large hailstones
Authors: Bilham E. G. , Relf E. F. 
Published: July 2010

AbstractThe form of the relation between terminal velocity and diameter is deduced from values of the drag coefficient obtained from observations on spheres towed by aeroplanes. Values of the terminal velocity are calculated for various mean specific gravities and it is concluded that an upper limit, about 1.5 lb., is set to the mass attainable by a spherical hailstone by aerodynamical considerations.
Photometric study o f atmospheric pollution
Authors: Digby W. P. 
Published: July 2010

AbstractA photometric method of comparing the loss of reflecting value through tarnishing of polished metal plates is described and shows the wide daiiy and seasonal effects of changes in the polluting media in the atmosphere for different metals simultaneously exposed in the same place.The different rates of tarnishing of the same metal plates exposed during the same week in rural, London and industrial areas are very marked.Extreme cases in Westminster for polished copper are losses of 38 and 50 per cent in five hours in December fogs, whereas on four successive days in February, 1936, the loss in five hours varied between 5 and 11 per cent. For a summer day in 1935 a 10 per cent loss in 24 hours seems normal.For short periods of say, one to two days in the winter and a week in the summer, copper is a good indicator. For longer periods “fine” silver is better. Aluminium responds slowly while the useful range of nickel appears t o be between those of copper and of silver.In two appendices, the loss of reflection value is correlated with independent measurements of sulphur in the atmosphere.Further lines of research are indicated.
The correlation of the amount of ozone with other characteristics of the atmosphere
Authors: Meetham A. R. , Dobson G. M. B. 
Published: July 2010

AbstractDay to day variations in the total amount of atmospheric ozone are shown to be more closely correlated with those of potential temperatures in the stratosphere than with those of any other function of temperature and pressure, or with those of any other geophysical phenomenon yet investigated. A method of correlating with a certain variable associated with surface pressure distribution is exploited, and of three upper air phenomena considered the height of the tropopause is found to have the closest correlation with this variable. A speculative explanation of the close connection of the amount of ozone with other characteristics of the atmosphere is offered.
A method of predicting night minimum temperatures
Authors: Boyden C. J. 
Published: July 2010

AbstractA simple general relationship, which appears to be applicable in any climate, is found connecting monthly mean values of maximum and minimum dry‐bulb temperatures with mean wet‐bulb temperatures. The formula is extended for predicting individual minimum temperatures on nights when there is no appreciable change of air‐mass between the times of maximum and minimum temperature, allowance being made for wind speed, cloudiness and fog formation.
Haboobs and instability in the sudan
Authors: Farquharson J. S. 
Published: July 2010

AbstractThe dust‐storms of the Sudan, called haboobs, are shown to be associated with thunder squalls. Several haboobs are discussed with particular reference to upper winds and upper air temperatures, an indication of the speeds of the vertical currents associated with a haboob being obtained on one occasion by means of a series of pilot balloon observations in close sequence. A value of 108for the coefficient of eddy diffusivity in a haboob is derived. Conditions associated with instability in the Sudan are investigated and it is suggested that they may be referred to a discontinuity between southwest monsoon and northeast trade, the slope of which is given by the expression:the symbols having the usual‐significance. A series of photographs taken with the co‐operation of the R.A.F. illustrates the conditions in some of the haboobs.
The theory of hailstone formation
Authors: Schuma T. E. W. 
Published: July 2010

AbstractA fairly detailed mathematical analysis is presented of the generally accepted theory that the formation of large hailstones is due to the capture of under‐cooled water drops which lie in their path. It is shown that the principal factors which determine the ultimate size of a hailstone are its average density, the height at which its nucleus is formed, the average upward velocity of the air and the concentration of condensed water in the region of the atmosphere where the temperature is below 0°C. The interrelation between these various factors is shown by means of a number of curves.It is further demonstrated that the values of water content of the clouds and of upward air velocities, measured or deduced independently, are sufficient to account for the formation of hailstones at least 8 cm. in diameter.The matter of the disposal of the latent heat of the water which solidifies on the surface of the hailstone is also examined in some detail, and it is shown that this heat is disposed of quite effectively, partly by conduction to the surrounding atmosphere and partly by evaporation from the surface of the hailstone. Only in the case where the surface temperature of the hailstone approaches 0°C. does its incapability to get rid of its surplus heat act as a factor retarding its rate of growth, and consequently its ultimate size.
Modern views on atmospheric electricity
Authors: Whipple F. J. W. 
Published: July 2010

AbstractThe central theme of the address is the circulation of electricity through the atmosphere.Clouds from which precipitation is falling act as generators of electricity. Recent worli by Sir George Simpson and Mr. F. J. Scrase supports the view that the separation of positive and negative electricity is mainly due to the impact of snow particles in the upper parts of the clouds. The snow particles carry negative electricity downwards and a current of positive electricity flows upwards to the “Heaviside layer” to come down again in distant places where fine weather happens to prevail.
Local temperature variations in the nottingham district
Authors: Tinn Arnold B. 
Published: July 2010

AbstractThe unusual temperature readings at Garforth and Wokingham, and later those of Mr. E. L. Hawke at Rickmansworth, suggested an examination of local records near Nottingham. The author has found that considerable variations occur in the Nottingham district, though the topography offers no unusual features. An area of relatively high land, with irregular spurs, stretches north‐north‐east from Nottingham Castle. The monthly values of three stations for the nine years 1928‐1936, and those of five other stations for other periods, are analysed. It is found that local differences of 10°F. in the minima may occur, and the mean monthly minima may differ by over 4°F. Average differences are tabulated. A detailed daily analysis of four stations is made for the two years April, 1935, to March, 1937. It shows that variations tend to be greatest with winds from north‐west through north to east, and least with south to west winds. Although fine weather, a rising barometer and a low humidity favour large variations, it appears that conditions producing low minima do not always give appreciable differences. Rainy, windy conditions bring the differences to a minimum. Differences of 6°F. in the maxima may occur on certain warm sunny days in summer, and variations of 8°F. in foggy conditions. Topographical features give Attenborough the most “continental” temperatures. The importance of uniformity in the hours of setting the thermometers is demonstrated, and positions are indicated where additional screens might give useful data.
The application of wet‐bulb potential temperature to air mass analysis. IV
Authors: Hewson E. W. 
Published: July 2010

AbstractThis paper describes:‐
The moisture content of subsiding polar continental air over North America, under conditions when there was no likelihood of an increase in the moisture content due to precipitation from overrunning air. Two situations of this type are discussed, and no evidence is found of any appreciable increase above 850 mb.
The degree of homogeneity in polar continental air masses. The vertical distributions of wet‐bulb potential temperature Θ1 as observed nearly simultaneously at adjacent stations within an air mass are discussed in relation to their effect on the accuracy of computations of subsidence.
The vertical velocity of air in the warm sector of a depression. It is shown that in the warm sector considered, the ascent of the air near the surface was nearly twice as rapid as that at about 600 mb. The vertical velocity of the surface air was of the order of 4 cm./sec., and that of the air at about 600 mb. was of the order of 2 cm./sec.
The effect of turbulence in the air near the surface. The changes of temperature and moisture content in the surface layers of a moving air mass are discussed in the light of the theory of turbulence, as developed by Richardson and Taylor.
Evaporation over catchment areas
Authors: Lloyd David 
Published: July 2010

AbstractSome of the most authentic data of the general rainfall over British drainage areas and the run‐off in annual periods are marshalled. The difference between these observed quantities of water—i.e., the losses in annual periods from all causes—is fundamentally accepted from other research to be principally the effect of evaporation including evapo‐transpiration.The paper examines the variation in the annual total loss over eight drainage areas by a statistical method. It is postulated that loss is a joint function of meteorological elements and the geological formation penetrated by any rain water; further, that in the present stage the joint functional causation can be simplified to one of separate functions. Thus, it is assumed that the variations in loss can be associated with the rainfall providing the opportunity for evaporation, with the temperature, with the sunshine, and (as following the primary loss in the zone of aeration, influent seepage may provide a flow in the zone of saturation which later may provide a deferred opportunity for evaporation from the capillary fringe and effluent seepage from ground water) with the geological formation. Regressions of loss on the available postulated controls have been inferred. By inductive reasoning, an equation is found approximately representing the observations over the eight areas, by which the annual loss expected on account of various influences can be estimated.
The intensity of ultra‐violet radiation from the sky in Iraq
Authors: Kennedy Walter P. , Wright H. L. 
Published: July 2010

AbstractHæmotological investigations in Baghdad suggested that the climate altered the blood of normal persons as compared with Britain, and as part of the analysis of the climatic factors, day‐today measurements were made of the ultra‐violet component of northern sky shine, using Owens's instrument. In this a Chance No. 14 filter is separated from a sheet of photographic paper by a graded series of tubes, giving a scale of 13 arbitrary values from 1 to 204. 'The upper end of the scale is much more open than the lower, and this must be considered a disadvantage in very bright conditions such as the Iraq summer. The instrument is exposed for 24 hours at 45° to the zenith pointing north.The daily measurements from August, 1936, to August, 1937, are given in graphic form, and also as monthly means. With the latter, various other meteorological data are tabulated to show the trend and range of climatic variation, and to indicate some of the major causes of fluctuation in the ultra‐violet values. The direction of influence of these variables is discussed briefly, but integration of the factors is not attempted. The paper is preliminary; further studies are in progress.
On the occurrence of snow‐cover in Great Britain
Authors: Manley G. 
Published: July 2010

AbstractHitherto practically no information has been forthcoming with regard to the frequency with which a snow‐cover may be expected on the uplands and mountains of Great Britain. Variations with altitude are very great; variations from year to year are also very great; few highland stations are available, while their records are often brief and interrupted. Further, the interpretation, analysis and criticism of the existing data with regard to snow‐lying are difficult, and are only to be undertaken after a close survey of the environment and other features of the reporting stations, of which the majority are on low ground.A relationship has now been derived between the mean temperature of the winter months and the average frequency of occurrence of snow‐lying, which after test appears to be generally applicable to any given place over a period of years. It is necessary, however, to allow for several additional factors, notably quantity of snowfall, which influence the duration if snow‐cover. It appears that, making these allowances, a reasonable estimate can be made of the frequency of snow‐cover a t the majority of places in Great Britain; also, of the extent to which the expectation of snow‐cover varies with small fluctuations in mean winter temperature, over a period.The deductions, with regard to uplands and mountains, should be of general interest to many beside those concerned with questions of transport.In the course of the work upwards of ninety observing stations have been investigated, and the tables of frequency of snow‐lying for eighty‐six of these may also be of value until more rigorous analysis can be undertaken.
A note on theories of the electric fields below clouds
Authors: Chalmers J. Alan 
Published: July 2010

AbstractAttention is drawn to the discrepancy between the electric fields actually existing below thunder clouds, as measured by the alti‐electrograph, and those expected on a theory due to Wilson. An attempt to remove the discrepancy by the consideration of the presence of negative ions as well as the positive ions produced by point discharge decreases, but does not remove it, and there remains an unsolved problem.
Direction‐finding of sources of atmospherics and South African Meteorology
Authors: Schonland B. F. J. , Hodges D. B. 
Published: July 2010

AbstractAn account is given of investigations on the location of sources of atmospherics in South Africa with visually‐operated cathode‐ray direction‐finders, extending over a period of fifteen months and employing stations in Johannesburg, Durban and Bulawayo.The accuracy with which a thunderstorm source can be located by this method was found to be ±50 km. for storms at distances less than 750 km. At greater distances the accuracy decreases but is usually less than ±100 km. at 1,500 km.Of the land sources 76 per cent. were identified with thunder‐clouds and 18 per cent. with nimbus cloud.Sources over the oceans were found t o be closely associated with areas of low pressure, 89 per cent of such lows having associated sources. The progress of the lows could be followed by this method for several days. Their associated sources in the majority of cases lay in the warm sector from NNE. to ESE. of the centre of the low.The monthly and seasonal distributions of sources over the land agree with the distributions found by Brooks from thunderstorm data, except that over the Indian Ocean the number of atmospherics sources reaches a maximum in the winter.A discussion is given of the possibilities of the device in meteorology in Southern Africa and of difficulties encountered in the practical day‐by‐day use of the system. A commentary follows by three officers of the Rhodesia Meteorological Service.
Local distribution of thunder rains round Nottingham
Authors: Tinn Arnold B. 
Published: July 2010

AbstractA belief exists in Nottingham that there is some relation between the paths of thunderstorms and the valley of the River Trent. This investigation was made with a view to testing this speculation and to discovering whether any tendency did exist in the local distribution of thunder rains round Nottingham. Information was obtained from 34 rain gauges for thunder days over a period of ten years, and the data charted and analysed.It is found that there are areas which appear to be more subject to heavy thunder rains, and also areas having a comparative immunity. There seems to be some basis for the belief that these rains do tend to be heavier near the River Trent, but this tendency is more marked for the stretch of valley between the confluences of the rivers Erewash and Leen with the Trent. Eastwards of the Leen the river valley appears to be less subject to the heaviest falls.
Atmospheric opacity at Valentia
Authors: Wright H. L. 
Published: July 2010

AbstractTo confirm the variation of atmospheric opacity with relative humidity, inferred in a previous paper from theoretical considerations, observations of visibility at Valentia are utilised to deduce values of atmospheric opacity. These values are grouped according to the relative humidity and the direction of the wind. Examination of the results shows beyond doubt that, in air free from smoke, opacity varies with relative humidity in a manner which corresponds very closely with that indicated by the theoretical equations, provided that in these equations suitable values are inserted for the number of nuclei and for a quantity depending on the mass of salt in each nucleus and its hygroscopic properties.
Evaportation‐loss per month from two drainage areas
Authors: Lloyd David 
Published: July 2010

AbstractMonthly data of the apparent loss by evaporation, etc., of moisture from Vyrnwy and Rivington drainage areas are examined in relation to the rainfall and the temperature.After discussing the subject matter, the association and the degree of association are determined on the hypothesis that variations in evaporation‐loss can be associated with the variations in rainfall and temperature in a joint functional manner. The regressions have been computed together with the formal evaluation of the significance of the statistics.The results show that, when the temperature is constant, the evaporation‐loss is proportional to the rainfall; when the rainfall has a given value, the loss increases in relation to the temperature; while the loss is reduced according to the previous rainfall. There is similarity in the relations at Vyrnwy and Rivington.
Theoretical aspects of the size distribution of fog particles
Authors: Schumann T. E. W. 
Published: July 2010

AbstractFollowing some very interesting work by Houghton and Radford on the determination of size distribution of drops in fogs and clouds, a theory is here presented to account for the experimental results obtained.The basis of the theory is that due to Brownian movement, to turbulence, and to the influence of gravity, collisions between the drops take place and thet upon collision coalescence results. There will thus be a gradual increase in the average size of the drops consutling the fog due to these collisions, and the problem with which one is confornted is to detemine what the resultant size distribution of the drops will be.In a simple case, where it is assumed that the frequency of distribution curve. The result thus obtained shows very satisfactory agreement with the experimental values given by Houghton and Radford.It has also been found possible to obtain an approximate theoretical value for the rate of growth of the “most preferred” drop sizes, but it would appear that in nature the rate of growth is several times more rapid than the theoretical value.The theory might prove useful in showing how research should be directed in order to arrive at a full understanding of the mechanism by which fogs and clouds are formed.
A new approach to the study of the seasonal incidence of british rainfall
Authors: Crowe P. R. 
Published: July 2010

AbstractThe rainfall records for the period 1881‐1930 of seventy British stations are analysed by a method of direct comparison of monthly values which does not involve the calculation of means. The tendency towards a regular annual régime of rainfall being rather weak over most of these islands, the object is to try and single out significant facts from the mass of detail which is purely fortuitous in character. The results are expressed in maps and tables.Taking the country as a whole the periods of most rapid change in precipitation conditions are shown to have been from June to August and from December to February. There is, however, a considerable amount of regional contrast, particularly in the comparison, of August with October values, whilst the distribution of anomalous conditions in September is also of interest.The analysis is then carried back to the period 1831‐1880 for twelve stations. The general verdict seems to be that rapid rainfall transitions during that period fell between April and June, October and December. The rainy period was thus the same length as in the later half century but occurred earlier in the year. At the same time the September anomaly disappeared.If the test of significance employed is not seriously at fault—and it would seem to err if anything on the side of severity—we must face the conclusion that the hypothesis of an ultimate normal of rainfall may have to be reconsidered.