Seasonal Effects on Ground-Wave propagation in Cold Regions
Abstract The ground-wave is the most important mode of propagation of radio waves in Connection with glaciology. In cold regions, special conditions are often prevalent, involving propagation over non-homogeneous earth, presence of stratified media, and low values of conductivity and dielectric cons...
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Cambridge University Press (CUP)
1975
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Online Access: | http://dx.doi.org/10.1017/s0022143000034444 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000034444 |
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crcambridgeupr:10.1017/s0022143000034444 2024-03-03T08:42:18+00:00 Seasonal Effects on Ground-Wave propagation in Cold Regions Blomquist, Ake 1975 http://dx.doi.org/10.1017/s0022143000034444 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000034444 en eng Cambridge University Press (CUP) Journal of Glaciology volume 15, issue 73, page 285-303 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1975 crcambridgeupr https://doi.org/10.1017/s0022143000034444 2024-02-08T08:47:47Z Abstract The ground-wave is the most important mode of propagation of radio waves in Connection with glaciology. In cold regions, special conditions are often prevalent, involving propagation over non-homogeneous earth, presence of stratified media, and low values of conductivity and dielectric constant in the upper strata. A radio wave which propagates along the Earth's surface is, however, also influenced by atmospheric refraction. As the frequency is increased, the roughness of the Earth's surface must also be taken into account. Thus seasonal variations are to be expected due to changes in the electrical and topographical properties of the ground as well as the propagation conditions in the atmosphere. It is, however, difficult to separate these various effects, a fact which reduces the possibility of using ground-wave propagation as a loot for obtaining information on the properties of the ground. Though the propagation of the ground-wave has been dealt with both theoretically and experimentally for almost a century, some of the most valuable information of major importance in cold regions has been obtained during the last ten years. New theoretical papers on propagation over stratified media offer an explanation of the amplitude and phase variations of the ground-wave field, which have been measured, as well as suggesting new methods to be tested as possible aids in solving glaciological problems. In many practical eases of ground-wave propagation in arctic regions, the formula for the ground-wave field strength can be written in a very simple way. Such a propagation model for frequencies above 30 MHz is presented in which account is taken of the Earth's curvature, the terrain irregularities, and the effect of the tropospheric refraction. This model also includes the recovery effect which occurs in propagation over mixed paths. At the higher frequencies the effect of depolarization becomes very important and sometimes overshadows field-strength variations due to the influence of the electrical properties. ... Article in Journal/Newspaper Arctic Journal of Glaciology Cambridge University Press Arctic Journal of Glaciology 15 73 285 303 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Blomquist, Ake Seasonal Effects on Ground-Wave propagation in Cold Regions |
topic_facet |
Earth-Surface Processes |
description |
Abstract The ground-wave is the most important mode of propagation of radio waves in Connection with glaciology. In cold regions, special conditions are often prevalent, involving propagation over non-homogeneous earth, presence of stratified media, and low values of conductivity and dielectric constant in the upper strata. A radio wave which propagates along the Earth's surface is, however, also influenced by atmospheric refraction. As the frequency is increased, the roughness of the Earth's surface must also be taken into account. Thus seasonal variations are to be expected due to changes in the electrical and topographical properties of the ground as well as the propagation conditions in the atmosphere. It is, however, difficult to separate these various effects, a fact which reduces the possibility of using ground-wave propagation as a loot for obtaining information on the properties of the ground. Though the propagation of the ground-wave has been dealt with both theoretically and experimentally for almost a century, some of the most valuable information of major importance in cold regions has been obtained during the last ten years. New theoretical papers on propagation over stratified media offer an explanation of the amplitude and phase variations of the ground-wave field, which have been measured, as well as suggesting new methods to be tested as possible aids in solving glaciological problems. In many practical eases of ground-wave propagation in arctic regions, the formula for the ground-wave field strength can be written in a very simple way. Such a propagation model for frequencies above 30 MHz is presented in which account is taken of the Earth's curvature, the terrain irregularities, and the effect of the tropospheric refraction. This model also includes the recovery effect which occurs in propagation over mixed paths. At the higher frequencies the effect of depolarization becomes very important and sometimes overshadows field-strength variations due to the influence of the electrical properties. ... |
format |
Article in Journal/Newspaper |
author |
Blomquist, Ake |
author_facet |
Blomquist, Ake |
author_sort |
Blomquist, Ake |
title |
Seasonal Effects on Ground-Wave propagation in Cold Regions |
title_short |
Seasonal Effects on Ground-Wave propagation in Cold Regions |
title_full |
Seasonal Effects on Ground-Wave propagation in Cold Regions |
title_fullStr |
Seasonal Effects on Ground-Wave propagation in Cold Regions |
title_full_unstemmed |
Seasonal Effects on Ground-Wave propagation in Cold Regions |
title_sort |
seasonal effects on ground-wave propagation in cold regions |
publisher |
Cambridge University Press (CUP) |
publishDate |
1975 |
url |
http://dx.doi.org/10.1017/s0022143000034444 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000034444 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Journal of Glaciology |
genre_facet |
Arctic Journal of Glaciology |
op_source |
Journal of Glaciology volume 15, issue 73, page 285-303 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000034444 |
container_title |
Journal of Glaciology |
container_volume |
15 |
container_issue |
73 |
container_start_page |
285 |
op_container_end_page |
303 |
_version_ |
1792497721722011648 |