THE RELATIONSHIPS BETWEEN THE SECULAR CHANGE AND THE NON-DIPOLE FIELDS

1958 ◽  
Vol 36 (10) ◽  
pp. 1372-1396 ◽  
Author(s):  
Kenneth Whitham
Keyword(s):  
Secular Variation ◽  
World Wide ◽  
Dipole Field ◽  
Secular Change ◽  
Average Value ◽  
Local Fluctuations ◽  
The World ◽  
Minimum Residual ◽  
Harmonic Analyses ◽  
Westward Drift

Using airborne, ground, and repeat magnetic observations in Canada compiled in the isomagnetic and isoporic charts for epoch 1955.0, the drift and decay contributions of the non-dipole field to the observed secular variation have been estimated. The drift rates which produce the minimum residual secular variation were found to be unusually small. It is then confirmed, using the longitude displacement method and isomagnetic data only, that the westward drift of the non-dipole field in recent years in Canada is significantly smaller than the world-wide average. These results clearly demonstrate the large local fluctuations which occur in westward drift.The two different methods were applied to obtain relationships between the Gaussian coefficients in the spherical harmonic analyses of the earth's main field and the secular variation. Calculations show that both methods give the accepted world-wide average value of westward drift, that one half of the world-wide secular variation is produced by westward drift, and in general decay terms are unimportant.

The westward drift of the Earth's magnetic field

1950 ◽  
Vol 243 (859) ◽  
pp. 67-92 ◽  
Keyword(s):  
Magnetic Field ◽  
Secular Variation ◽  
Outer Part ◽  
Earth’S Magnetic Field ◽  
Dynamo Theory ◽  
The Core ◽  
The Earth ◽  
Earth's Magnetic Field ◽  
Harmonic Analyses ◽  
Westward Drift

The westward drift of the non-dipole part of the earth’s magnetic field and of its secular variation is investigated for the period 1907-45 and the uncertainty of the results discussed. It is found that a real drift exists having an angular velocity which is independent of latitude. For the non-dipole field the rate of drift is 0.18 ± 0-015°/year, that for the secular variation is 0.32 ±0-067°/year. The results are confirmed by a study of harmonic analyses made between 1829 and 1945. The drift is explained as a consequence of the dynamo theory of the origin of the earth’s field. This theory required the outer part of the core to rotate less rapidly than the inner part. As a result of electromagnetic forces the solid mantle of the earth is coupled to the core as a whole, and the outer part of the core therefore travels westward relative to the mantle, carrying the minor features of the field with it.

COMPARISON OF WORLD WIDE LIGHTNING LOCATION NETWORK (WWLLN) DATA AND STANDARD OBSERVATIONS AT WEATHER STATIONS IN THE SOUTHERN RUSSIAN FAR EAST

2021 ◽  
pp. 89-98
Author(s):  
T. I. Kleshcheva ◽  
◽  
E. Yu. Potalova ◽  
M. S. Permyakov ◽  
◽  
...  
Keyword(s):  
World Wide ◽  
Russian Far East ◽  
Far East ◽  
Annual Number ◽  
Weather Station ◽  
Average Value ◽  
The World ◽  
Weather Stations ◽  
Average Annual Number ◽  
The Russian Far East

Standard observations at 20 weather stations were compared with data of the World Wide Lightning Location Network (WWLLN) in the south of the Russian Far East for the period of 2009-2018. Using two statistical methods, the estimates are obtained of the radii of the circular region of the WWLLN data sample, at which the best consistency of the WWLLN data with the number of days with thunderstorms according to weather station data is observed. It is shown that these radii are in the range from 12 to 36 km for all stations, with an average value of 23 km. Daytime radii are smaller than nighttime ones, the average values for all stations are equal to 21 and 26 km, respectively. It is demonstrated that an increase/decrease in the radius of the WWLLN data sample by 1 km leads to an increase/decrease in the average annual number of days with WWLLN lightnings relative to weather reports by ~1 day.

Rotational Characteristics of the Green Solar Corona: 1947-1991

1994 ◽  
Vol 144 ◽  
pp. 139-141 ◽  
Author(s):  
J. Rybák ◽  
V. Rušin ◽  
M. Rybanský
Keyword(s):  
Solar Corona ◽  
World Wide ◽  
Rotation Period ◽  
Original Data ◽  
Coronal Emission ◽  
Time Intervals ◽  
Data Set ◽  
The World ◽  
Coronal Emission Line ◽  
Homogeneous Data

AbstractFe XIV 530.3 nm coronal emission line observations have been used for the estimation of the green solar corona rotation. A homogeneous data set, created from measurements of the world-wide coronagraphic network, has been examined with a help of correlation analysis to reveal the averaged synodic rotation period as a function of latitude and time over the epoch from 1947 to 1991.The values of the synodic rotation period obtained for this epoch for the whole range of latitudes and a latitude band ±30° are 27.52±0.12 days and 26.95±0.21 days, resp. A differential rotation of green solar corona, with local period maxima around ±60° and minimum of the rotation period at the equator, was confirmed. No clear cyclic variation of the rotation has been found for examinated epoch but some monotonic trends for some time intervals are presented.A detailed investigation of the original data and their correlation functions has shown that an existence of sufficiently reliable tracers is not evident for the whole set of examinated data. This should be taken into account in future more precise estimations of the green corona rotation period.

Dancing Across the World Wide Web: Advocacy in the 21st Century

2009 ◽  
Author(s):  
Blair Williams Cronin ◽  
Ty Tedmon-Jones ◽  
Lora Wilson Mau
Keyword(s):  
World Wide Web ◽  
21St Century ◽  
World Wide ◽  
The World

Biodiesel production from non-edible oils: A review

2020 ◽  
pp. 149-159
Author(s):  
Jatinder Kataria ◽  
Saroj Kumar Mohapatra ◽  
Amit Pal
Keyword(s):  
Environmental Impact ◽  
Energy Demand ◽  
Fossil Fuels ◽  
World Wide ◽  
Edible Oils ◽  
Control Measure ◽  
Biodiesel Production ◽  
Pollution Level ◽  
Animal Fats ◽  
The World

The limited fossil reserves, spiraling price and environmental impact due to usage of fossil fuels leads the world wide researchers’ interest in using alternative renewable and environment safe fuels that can meet the energy demand. Biodiesel is an emerging renewable alternative fuel to conventional diesel which can be produced from both edible and non-edible oils, animal fats, algae etc. The society is in dire need of using renewable fuels as an immediate control measure to mitigate the pollution level. In this work an attempt is made to review the requisite and access the capability of the biodiesel in improving the environmental degradation.

THE EUROPEAN UNION FORUM ON KIDS' SAFETY IN INTERNET SIF 2019

2019 ◽  
pp. 3-6
Author(s):  
D. A. Bogdanova
Keyword(s):  
European Union ◽  
World Wide Web ◽  
World Wide ◽  
The European Union ◽  
Internet Forum ◽  
The World

The article provides an overview of the activities of the European Union Forum on kids' safety in Internet — Safer Internet Forum (SIF) 2019, which was held in Brussels, Belgium, in November 2019. The current Internet risks addressed by the World Wide Web users, especially children, are described.

Profilometry. Using Corneo-scleral topography for scleral lens fitting

The Eye ◽  
2019 ◽  
Vol 21 (128) ◽  
pp. 19-22
Author(s):  
Gregory DeNaeyer
Keyword(s):  
Ocular Surface ◽  
World Wide ◽  
Contact Lenses ◽  
The Past ◽  
The World ◽  
The Future ◽  
The Way

The world-wide use of scleral contact lenses has dramatically increased over the past 10 year and has changed the way that we manage patients with corneal irregularity. Successfully fitting them can be challenging especially for eyes that have significant asymmetries of the cornea or sclera. The future of scleral lens fitting is utilizing corneo-scleral topography to accurately measure the anterior ocular surface and then using software to design lenses that identically match the scleral surface and evenly vault the cornea. This process allows the practitioner to efficiently fit a customized scleral lens that successfully provides the patient with comfortable wear and improved vision.

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