Author: Raymond J. Cormier
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 28
Book Description
Qualitative descriptions of the morphology of Polar Cap Absorption (PCA) events are given, using data from the following riometer stations: Thule and Godhavn, Greenland; Churchill Range, Manitoba, Canada; and Reykjavik (Leirvogur), Iceland. The dependence of commencement time on solar zenith angle and subsequent daily variations in absorption following the initial day are described. The morphology of PCA events is very important for forecasting the behavior of ionospheric absorption during a PCA event. It is shown that besides information concerning the energy spectrum of the proton flux, the season and time of day must also be considered for forecasting the expected absorption. (Author).
Polar Riometer Observations
Author: Raymond J. Cormier
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 28
Book Description
Qualitative descriptions of the morphology of Polar Cap Absorption (PCA) events are given, using data from the following riometer stations: Thule and Godhavn, Greenland; Churchill Range, Manitoba, Canada; and Reykjavik (Leirvogur), Iceland. The dependence of commencement time on solar zenith angle and subsequent daily variations in absorption following the initial day are described. The morphology of PCA events is very important for forecasting the behavior of ionospheric absorption during a PCA event. It is shown that besides information concerning the energy spectrum of the proton flux, the season and time of day must also be considered for forecasting the expected absorption. (Author).
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 28
Book Description
Qualitative descriptions of the morphology of Polar Cap Absorption (PCA) events are given, using data from the following riometer stations: Thule and Godhavn, Greenland; Churchill Range, Manitoba, Canada; and Reykjavik (Leirvogur), Iceland. The dependence of commencement time on solar zenith angle and subsequent daily variations in absorption following the initial day are described. The morphology of PCA events is very important for forecasting the behavior of ionospheric absorption during a PCA event. It is shown that besides information concerning the energy spectrum of the proton flux, the season and time of day must also be considered for forecasting the expected absorption. (Author).
Goose Bay Riometer Observations
Author: Raymond J. Cormier
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 32
Book Description
At Goose Bay, Labrador, 30-MHz riometers using a four-corner reflector antenna have been in operation since November 1971. An 18-MHz riometer using a zenith-pointing antenna has been operational since June 1972. A quiet day curve of 30 MHz has been constructed for the Goose Bay 30 MHz, and useful hours of operation for an 18-MHz riometer at this particular site are discussed. The usefulness of the four-corner reflector antenna over a single zenith-pointing antenna is discussed, in particular, in an auroral environment. Examples of data illustrating the performance of the antenna system are presented. The data selected are for the geomagnetically active period of mid-April to early May 1973. (Author).
Publisher:
ISBN:
Category : Ionosphere
Languages : en
Pages : 32
Book Description
At Goose Bay, Labrador, 30-MHz riometers using a four-corner reflector antenna have been in operation since November 1971. An 18-MHz riometer using a zenith-pointing antenna has been operational since June 1972. A quiet day curve of 30 MHz has been constructed for the Goose Bay 30 MHz, and useful hours of operation for an 18-MHz riometer at this particular site are discussed. The usefulness of the four-corner reflector antenna over a single zenith-pointing antenna is discussed, in particular, in an auroral environment. Examples of data illustrating the performance of the antenna system are presented. The data selected are for the geomagnetically active period of mid-April to early May 1973. (Author).
Correlated Interplanetary and Magnetospheric Observations
Author: D.E. Page
Publisher: Springer Science & Business Media
ISBN: 9401021724
Category : Science
Languages : en
Pages : 639
Book Description
The 1969 ESLAB symposium 'Intercorrelated Satellite Observations Related to Solar Events' was held at a time when the importance of bringing together measure ments made simultaneously in different regions of space was beginning to be appreciated. To-day it is universally accepted that the major experimental steps forward in understanding the physics of the Sun-Earth relationships are likely to be made through pre-planned correlated satellite studies. Such considerations have led to the organisation of the International Magnetospheric Study and the joint ESROj NASA International Magnetospheric Explorer, (Mother-Daughter-Heliocentric) mission. The seventh ESLAB symposium was planned as a follow up to that of 1969 with the aim of deriving maximum benefit from those spacecraft which through good fortune found themselves simultaneously operating in different regions of the magnetosphere and interplanetary space. ESRO had launched in early 1972 its HEOS-2 satellite to investigate fields and particles in the unexplored region far above the North pole of the Earth and it became clear that the interesting new results arriving from that mission could profitably be linked with those from various American and the U.S.S.R. PROGNOZ satellites. The book follows the order of the symposium (unfortunately the PROGNOZ contribution did not materialise) concentrating, through both review lectures and of new experimental results, on the nature of the boundaries between the presentation the interplanetary medium and the magnetosphere and the interaction of each region on the other.
Publisher: Springer Science & Business Media
ISBN: 9401021724
Category : Science
Languages : en
Pages : 639
Book Description
The 1969 ESLAB symposium 'Intercorrelated Satellite Observations Related to Solar Events' was held at a time when the importance of bringing together measure ments made simultaneously in different regions of space was beginning to be appreciated. To-day it is universally accepted that the major experimental steps forward in understanding the physics of the Sun-Earth relationships are likely to be made through pre-planned correlated satellite studies. Such considerations have led to the organisation of the International Magnetospheric Study and the joint ESROj NASA International Magnetospheric Explorer, (Mother-Daughter-Heliocentric) mission. The seventh ESLAB symposium was planned as a follow up to that of 1969 with the aim of deriving maximum benefit from those spacecraft which through good fortune found themselves simultaneously operating in different regions of the magnetosphere and interplanetary space. ESRO had launched in early 1972 its HEOS-2 satellite to investigate fields and particles in the unexplored region far above the North pole of the Earth and it became clear that the interesting new results arriving from that mission could profitably be linked with those from various American and the U.S.S.R. PROGNOZ satellites. The book follows the order of the symposium (unfortunately the PROGNOZ contribution did not materialise) concentrating, through both review lectures and of new experimental results, on the nature of the boundaries between the presentation the interplanetary medium and the magnetosphere and the interaction of each region on the other.
Polar Cap Boundary Phenomena
Author: Jøran Moen
Publisher: Springer Science & Business Media
ISBN: 9401152144
Category : Science
Languages : en
Pages : 446
Book Description
These proceedings are based on the invited talks and selected research reports presented at the NATO Advanced Study Institute (ASI) on "POLAR CAP BOUNDARY PHENOMENA" held at Longyearbyen, Svalbard, June 4 - 13, 1997. The role of the polar cap and its boundary is very substantial in solar-terrestrial physics. At this NATO AS! a major change in thinking on the "cusp" precipitation region in the high-latitude days ide upper atmosphere was reflected, at least for intervals when the interplanetary magnetic field (IMF) is directed southward. It is likely that this has implications for northward IMF as well. The change comes from the now almost complete acceptance of the concept of magnetosheath particle entry along open magnetic field lines and the evolution of the precipitation into the upper atmosphere with time elapsed since magnetic reconnection which opened the field line. A key prediction of this view is that the low-latitude boundary layer (LLBL) is on open field lines.
Publisher: Springer Science & Business Media
ISBN: 9401152144
Category : Science
Languages : en
Pages : 446
Book Description
These proceedings are based on the invited talks and selected research reports presented at the NATO Advanced Study Institute (ASI) on "POLAR CAP BOUNDARY PHENOMENA" held at Longyearbyen, Svalbard, June 4 - 13, 1997. The role of the polar cap and its boundary is very substantial in solar-terrestrial physics. At this NATO AS! a major change in thinking on the "cusp" precipitation region in the high-latitude days ide upper atmosphere was reflected, at least for intervals when the interplanetary magnetic field (IMF) is directed southward. It is likely that this has implications for northward IMF as well. The change comes from the now almost complete acceptance of the concept of magnetosheath particle entry along open magnetic field lines and the evolution of the precipitation into the upper atmosphere with time elapsed since magnetic reconnection which opened the field line. A key prediction of this view is that the low-latitude boundary layer (LLBL) is on open field lines.
Antarctic Journal of the United States
Environmental Research Papers
Author:
Publisher:
ISBN:
Category : Environmental geology
Languages : en
Pages : 232
Book Description
Publisher:
ISBN:
Category : Environmental geology
Languages : en
Pages : 232
Book Description
Riometry as an Aid to Ionospheric Forecasting
Author: Raymond J. Cormier
Publisher:
ISBN:
Category : Atmospheric physics
Languages : en
Pages : 46
Book Description
The report deals with the use of riometers as an aid in ionospheric forecasting during both disturbed and undisturbed conditions at various geographical regions of the earth. Both the physical and technical aspects of riometry are discussed. Riometer observations during special solar geophysical events such as polar cap absorptions, auroral absorptions, and solar flare effects are presented and discussed. Suggestions for the improvement of riometer output and a description of experiments to be performed using riometers as an integral part of forecasting systems are presented. (Author).
Publisher:
ISBN:
Category : Atmospheric physics
Languages : en
Pages : 46
Book Description
The report deals with the use of riometers as an aid in ionospheric forecasting during both disturbed and undisturbed conditions at various geographical regions of the earth. Both the physical and technical aspects of riometry are discussed. Riometer observations during special solar geophysical events such as polar cap absorptions, auroral absorptions, and solar flare effects are presented and discussed. Suggestions for the improvement of riometer output and a description of experiments to be performed using riometers as an integral part of forecasting systems are presented. (Author).
A Catalog of Proton Events, 1966-1976, Having Non-classical Solar Radio Burst Spectra
Author: John P. Castelli
Publisher:
ISBN:
Category : Protons
Languages : en
Pages : 50
Book Description
A catalog of about 118 proton events, 1966-1976, not included in an earlier catalog of 81 events (AFGL TR-77-0081) for the same period is presented. These 118 events combined with the earlier 81 provide the basis for summarizing solar radio burst/high-energy proton correlation and prediction signature work. In the earlier effort, hereafter called Catalog I, the starting point was the identification of all solar radio bursts having the classical U-shape spectrum, and then establishing proton event association for the purpose of devising a reliable 'false-alarm' free predictor of the major proton events (equivalent PCA 2-2. 5dB). In the present effort, the starting point is the identification of all other proton events not included in Catalog I (misses by the U-shape spectrum criteria), and then searching for the establishing solar radio correlations and possible predictions of weaker proton events. There are very few real misses of principal proton events.
Publisher:
ISBN:
Category : Protons
Languages : en
Pages : 50
Book Description
A catalog of about 118 proton events, 1966-1976, not included in an earlier catalog of 81 events (AFGL TR-77-0081) for the same period is presented. These 118 events combined with the earlier 81 provide the basis for summarizing solar radio burst/high-energy proton correlation and prediction signature work. In the earlier effort, hereafter called Catalog I, the starting point was the identification of all solar radio bursts having the classical U-shape spectrum, and then establishing proton event association for the purpose of devising a reliable 'false-alarm' free predictor of the major proton events (equivalent PCA 2-2. 5dB). In the present effort, the starting point is the identification of all other proton events not included in Catalog I (misses by the U-shape spectrum criteria), and then searching for the establishing solar radio correlations and possible predictions of weaker proton events. There are very few real misses of principal proton events.
Geophysics and Space Data Bulletin
Technical Publications Announcements with Indexes
Author: United States. National Aeronautics and Space Administration
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1318
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1318
Book Description