THE ATMOSPHERIC POTENTIAL GRADIENT AT OTTAWA, CANADA

1937 ◽  
Vol 15a (8) ◽  
pp. 119-148 ◽  
Author(s):  
D. C. Rose
Keyword(s):  
Diurnal Variation ◽  
Potential Gradient ◽  
Meteorological Conditions ◽  
Fine Weather ◽  
Points Of View ◽  
Set Up ◽  
A Site

The atmospheric potential gradient was observed continuously at the National Research Laboratories at Ottawa for a year ending December 1, 1935, and at a country station about nine miles northwest of Ottawa, for four months ending November 1, 1936. The country station was set up on a site as free as possible from man-made pollution of the atmosphere. The records were studied from two points of view, the diurnal variation and disturbances in the normal fine weather value of the potential gradient. The results indicate that the diurnal variation is similar to that of other similarly situated stations. The study of disturbances in the potential gradient shows that all disturbances can be correlated with local meteorological conditions. The disturbances were for the most part associated with the stormy conditions usual at the passage of a front. The effect of city pollution on potential gradient records is clearly shown.

scholarly journals On the electricity of rain and snow

1910 ◽  
Vol 83 (564) ◽  
pp. 394-404 ◽  
Keyword(s):  
Rainy Season ◽  
Potential Gradient ◽  
Rain Gauge ◽  
Fine Weather ◽  
Electrical Capacity ◽  
Suitable Site ◽  
Second Year ◽  
Set Up ◽  
Normal Potential ◽  
Made In

In connection with a theory of the electricity of thunderstorms published in the ‘Philosophical Transactions,’ measurements of the charges of rain were made in 1908, and it appeared advisable that these should be continued for a second year. 1. The removal of the Simla Meteorological Office near the end of 1908 offered a suitable site, and the hut containing the apparatus was accordingly dismantled and set up afresh in the grounds of the new building. In all essentials the arrangement of the instruments remained as described in the previous paper, but it was found after the removal and readjustment of the instruments that the electrical capacity of the rain receiver had changed from 141 cm. to 150 cm. The rain gauge was also readjusted so that each tip of the bucket now corresponded to 0·11 mm. of rain instead of 0·14, as before the alteration. The apparatus for recording the potential gradient was modified so that it could be used during fine weather for registering the normal potential gradient. This was effected by fixing a more powerful radium collector to the insulated rod passing out into the open. The new site was found to be much less frequented by spiders than the old, so that practically no difficulty was experienced from discharging of the apparatus by their webs. All the instruments worked satisfactorily throughout the rainy season and only a very few periods of rain were not successfully investigated.

Eels Under Standing Wave Conditions

1982 ◽  
Vol 40 ◽  
pp. 492-495
Author(s):  
O.L. Krivanek ◽  
J. TaftØ
Keyword(s):  
Standing Wave ◽  
Wave Conditions ◽  
Set Up ◽  
A Site ◽  
Complex Crystal

It is well known that a standing electron wavefield can be set up in a crystal such that its intensity peaks at the atomic sites or between the sites or in the case of more complex crystal, at one or another type of a site. The effect is usually referred to as channelling but this term is not entirely appropriate; by analogy with the more established particle channelling, electrons would have to be described as channelling either through the channels or through the channel walls, depending on the diffraction conditions.

scholarly journals I.—Secular Earth-Creep

1909 ◽  
Vol 6 (4) ◽  
pp. 145-148 ◽  
Author(s):  
E. H. L. Schwarz
Keyword(s):  
South Africa ◽  
Diurnal Variation ◽  
Royal Society ◽  
The Sun ◽  
Special Design ◽  
Important Paper ◽  
Preliminary Results ◽  
Gravitational Pull ◽  
Set Up ◽  
Horizontal Pendulum

Dr. J. R. Sutton has recently read a most important paper to the Royal Society of South Africa on the diurnal variation of level at Kimberley. The paper gave the preliminary results of observations made during the course of three years upon the variation of the level of the ground as recorded by a large horizontal pendulum of a special design made for the author by the Cambridge Instrument Company. It appeared from the results that the movements in the surface of the ground, which set up corresponding movements in the pendulum, were very great. The maximum westerly elongation of the extremity of the pendulum occurred about 5.30 a.m., the maximum easterly about 4.15 p.m., the medium positions a little before 11 a.m. and 9.30 p.m. Geometrically these movements may be represented on the hypothesis that the hemisphere facing the sun bulges out, forming a sort of meniscus to the geosphere. The rise and fall of the surface of the ground which such a supposition would postulate is enormous, and the very magnitude has led Dr. Sutton to hesitate in giving the figures. There can, however, be very little doubt that some rise and fall in the earth's surface is occasioned by the sun's gravitational pull, although the present figures may have to be lessened by taking into consideration other causes which contribute to the disturbance of the pendulum.

scholarly journals Effects of Malaise trap spacing on species richness and composition of terrestrial arthropod bulk samples

2020 ◽  
Author(s):  
D Steinke ◽  
TWA Braukmann ◽  
L Manerus ◽  
A Woodhouse ◽  
V Elbrecht
Keyword(s):  
Species Richness ◽  
Field Experiments ◽  
Collection Efficiency ◽  
Malaise Trap ◽  
Number Of Factors ◽  
Large Numbers ◽  
Set Up ◽  
Taxonomic Groups ◽  
A Site ◽  
Malaise Traps

AbstractThe Malaise trap has gained popularity for assessing diverse terrestrial arthropod communities because it collects large samples with modest effort. A number of factors that influence collection efficiency, placement being one of them. For instance, when designing larger biotic surveys using arrays of Malaise traps we need to know the optimal distance between individual traps that maximises observable species richness and community composition. We examined the influence of spacing between Malaise traps by metabarcoding samples from two field experiments at a site in Waterloo, Ontario, Canada. For one experiment, we used two trap pairs deployed at weekly increasing distance (3m increments from 3 to 27 m). The second experiment involved a total of 10 traps set up in a row at 3m distance intervals for three consecutive weeks.Results show that community similarity of samples decreases over distance between traps. The amount of species shared between trap pairs shows drops considerably at about 15m trap-to-trap distance. This change can be observed across all major taxonomic groups and for two different habitat types (grassland and forest). Large numbers of OTUs found only once within samples cause rather large dissimilarity between distance pairs even at close proximity. This could be caused by a large number of transient species from adjacent habitat which arrive at the trap through passive transport, as well as capture of rare taxa, which end up in different traps by chance.

A survey of the microseisms recorded at Aberdeen in 1955, together with a review of the meteorological conditions under which they may have arisen

1958 ◽  
Vol 48 (1) ◽  
pp. 65-76
Author(s):  
A. E. M. Geddes
Keyword(s):  
Fast Moving ◽  
Rayleigh Waves ◽  
Standing Waves ◽  
Meteorological Conditions ◽  
Love Waves ◽  
Norwegian Coast ◽  
Pressure Distributions ◽  
Moving Storm ◽  
Set Up ◽  
Rocky Coast

Abstract As observations of microseisms at Aberdeen appeared to indicate that microseisms may arise from a cause or causes other than from standing waves set up by reflection from a steep rocky coast or by a mixture of waves in a fast-moving storm, a survey of Aberdeen records for 1955 has been carried out and a comparison made with the meteorological conditions prevailing at the time. A noticeable feature on the weather charts was the frequent occurrence of pressure distributions with two centres, while the occasions on which fast-moving storms occurred, or reflection from rocky coasts, were rare. Consequently there seemed to be grounds for supposing that the standing waves arose from the interference of two sets of wave systems generated by double low-pressure centres. Further, single low centres off either the Norwegian coast or that of America produced very little effect at Aberdeen. The survey suggests that the principal regions where such microseisms were produced appeared to be in the Atlantic north of 50° N and off the rocky coast of northwest Scotland. From a comparison of the displacements on the E-W and N-S records there is some support for the hypothesis that microseisms are due to a mixture of Rayleigh waves and Love waves.

Current proposals for the Thames barrier and the organization of the investigations

1972 ◽  
Vol 272 (1221) ◽  
pp. 179-185 ◽  
Keyword(s):  
Meteorological Conditions ◽  
The Third ◽  
River Thames ◽  
High Level ◽  
A Site ◽  
Very High

A considerable area of London close to the River Thames is liable to flood if the water in the river reaches an exceptionally high level. The very high waters which occur from time to time due to exceptional meteorological conditions are steadily increasing in level. After considering the possible ways of meeting this threat, by raising the existing flood defences, constructing a barrage across the mouth of the estuary, or the provision of a removeable flood barrier, to be closed only when a dangerous surge tide was liable to occur, the third course has been chosen as the best method. A site in Woolwich Reach has been chosen for a structure with four main openings of 61 m (200 ft), and the rising sectorf gate has been selected as the type of gate to be developed for the main openings.

scholarly journals Communication as a moral vocation: Safe space and freedom of speech

2019 ◽  
Vol 68 (1) ◽  
pp. 3-16
Author(s):  
David W. Hill
Keyword(s):  
Emmanuel Levinas ◽  
Cultural Theory ◽  
Max Weber ◽  
Judith Butler ◽  
Freedom Of Speech ◽  
Safe Spaces ◽  
Liberal Democratic ◽  
Set Up ◽  
A Site ◽  
The University

The use of safe spaces in universities has become increasingly controversial over the last few years. Safe spaces are set up to offer an environment in which marginalised identities and hidden experiences can be given a voice, allowing for acceptance and affirmation. Their critics charge that they are at odds with the university as a site of debate; that their use has a chilling effect on free speech; and even that safe spaces are harmful to liberal democratic society itself. This article draws on social and cultural theory in order to counter these attacks on safe spaces. Working with Max Weber, Judith Butler and Emmanuel Levinas, the first section introduces the idea of communication as a moral vocation, calling for greater recognition of the need to balance the universal (freedom of speech) with a responsibility to hear voices that are not already amplified. Building on this, and drawing additionally on Jacques Derrida and Sara Ahmed, the second section introduces the idea of debate fetishism, which serves to negate the moral function of communication, naturalise the dominance of privileged voices, and neutralise the struggles of the struggling to be heard. It is concluded that safe spaces pose no threat to freedom of speech but that the stigmatisation of their use acts to further disadvantage underrepresented identities.

scholarly journals V. Atmospheric electricity potential gradient at Kew Observatory, 1898 to 1912

1915 ◽  
Vol 215 (523-537) ◽  
pp. 133-159 ◽  
Keyword(s):  
Diurnal Variation ◽  
Atmospheric Electricity ◽  
Potential Gradient ◽  
Barometric Pressure ◽  
One Year ◽  
Meteorological Elements

In a previous paper, called E 1 for brevity, I discussed the results obtained for the diurnal variation of the potential gradient of atmospheric electricity at Kew Observatory from 1898 to 1904. The present paper deals with the same subject, but employs data from the fifteen years 1898 to 1912. The earlier period of seven years, though longer than that available at most observatories, was too short to give a satisfactorily representative presentation of some of the phenomena. To obtain results fairly characteristic of the locality many years data are required of some of the meteorological elements, especially barometric pressure and rainfall. For the latter element, in fact, a considerably longer period is desirable than that available even now for potential gradient at Kew. The same may be true of potential gradient itself, but various reasons exist for not waiting longer. Owing to building operations, the electrograph results for 1913 were exposed to special uncertainties. Also the transfer of the electrograph from the position it has occupied since 1898 is now in contemplation. Thus 1912 may be regarded as ending an epoch. Another reason requires fuller explanation. The Kew water-dropper—the earliest it is believed in regular operation—was erected in 1861 under Lord Kelvin’s personal supervision. The original electrometer and batteries as they decayed were replaced by others, but the instrument remained essentially unchanged in its original site until 1896. Of the records obtained prior to that date those of only three years had been discussed, two years, 1862 to 1864, by Prof. J. D. Everett, and one year, 1880, by Mr. G. M Whipple. In both cases the results were expressed in what were really arbitrary units. The relation between the voltage shown by the instrument and the true potential gradient in the open was altogether unknown.

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