Periodic Reporting for period 1 - MICAWA (Magnetosphere-Ionosphere Coupling and Associated Wave Activity)
Okres sprawozdawczy: 2019-05-01 do 2021-04-30
The project aims to contribute to the understanding of auroral AGWs/TIDs, by providing a better description of their characteristics and variability, as well as investigating the possible link to geomagnetic activity.
The project is expected to make a strong impact in the areas of space and atmospheric science: physics of AGWs and TIDs, magnetosphere-ionosphere coupling, data processing and analysis techniques and numerical modelling of the thermosphere-ionosphere.
The project has three major objectives:
O1: Determine the spectral characteristics of the AGW / TID activity, including their temporal and altitude variations, using plasma frequency and ionospheric tilt measurements.
O2: Determine the statistical distribution of propagation parameters (vertical and horizontal wavelength, phase speed, propagation direction), while also studying their temporal and altitude variation.
O3: Investigate possible correlations between parameters describing AGW / TID activity and indices describing the level of geomagnetic activity (Kp and Ap index), both during periods of increased geomagnetic activity.
All three objectives have been successfully achieved, the project having produced a repository of data and a catalogue describing TID activity at Tromso for a 7-year period between 2012-2018, available on the project website.
Additionally, a significant geophysical result was achieved in demonstrating in a statistical sense the correlation between geomagnetic activity and the level of ionospheric variability over a large time interval under mostly quiet geomagnetic conditions.
The project is expected to make a strong impact in the areas of space and atmospheric science: physics of AGWs and TIDs, magnetosphere-ionosphere coupling, data processing and analysis techniques and numerical modelling of the thermosphere-ionosphere.
The project has three major objectives:
O1: Determine the spectral characteristics of the AGW / TID activity, including their temporal and altitude variations, using plasma frequency and ionospheric tilt measurements.
O2: Determine the statistical distribution of propagation parameters (vertical and horizontal wavelength, phase speed, propagation direction), while also studying their temporal and altitude variation.
O3: Investigate possible correlations between parameters describing AGW / TID activity and indices describing the level of geomagnetic activity (Kp and Ap index), both during periods of increased geomagnetic activity.
All three objectives have been successfully achieved, the project having produced a repository of data and a catalogue describing TID activity at Tromso for a 7-year period between 2012-2018, available on the project website.
Additionally, a significant geophysical result was achieved in demonstrating in a statistical sense the correlation between geomagnetic activity and the level of ionospheric variability over a large time interval under mostly quiet geomagnetic conditions.
The planned work was grouped into 5 work packages with 15 tasks, all of which were achieved.
Work Package 1 encompassed four tasks related to creating a local repository of data and most of the time-domain processing and analysis. The initial work-plan required the use of datasets covering a total of three years (2014-2016) from the Tromso Dynasonde. Throughout the implementation of the project, a significantly higher amount of data was used, namely electron density and ionospheric tilts from January 2012 to December 2018.
WP 2 encompassed three tasks related to performing the spectral analysis of dynasonde data. This work required two separate directions, one involving the determination of long-term Power Spectral Densities (PSDs), and another the instantaneous spectral characteristics of the data. For both of these efforts, the Lomb-Scargle method was used, due to the need for equivalent results obtained from data characterized by non-uniform sampling, that also varies strongly with altitude and time.
WP 3 encompassed two tasks related to determining the propagation parameters associated with AGW induced TIDs, and determining the statistical distribution of these parameters.
WP 4 encompassed three tasks related to investigating possible correlations between ionospheric disturbances and geomagnetic activity. Two approaches were found to be successful in this: First, using the integral of the PSDs determined as part of WP 2 and the Kp index, the correlation between the dominant spectrum of ionospheric disturbances and geomagnetic activity was investigated for the entire 7-year period at Tromso. Second, by using additional data from the NOAA-NCEI ionosonde database, the ionospheric response to a series of geomagnetic events was investigated.
WP 5 encompassed three tasks associated with dissemination and communication activities. As part of this, one paper was published in the Journal of Geophysical Research: Space Physics, one manuscript is in review at the journal Surveys in Geophysics and an additional manuscript is in development. Additionally, three conference presentations were given, with several more planned as soon as travel restrictions and other pandemic related problems will no longer be an issue. Finally, a number of public presentations and demonstrations were performed involving the broader public, and more have been planned to take place as soon as public gatherings can safely resume.
Work Package 1 encompassed four tasks related to creating a local repository of data and most of the time-domain processing and analysis. The initial work-plan required the use of datasets covering a total of three years (2014-2016) from the Tromso Dynasonde. Throughout the implementation of the project, a significantly higher amount of data was used, namely electron density and ionospheric tilts from January 2012 to December 2018.
WP 2 encompassed three tasks related to performing the spectral analysis of dynasonde data. This work required two separate directions, one involving the determination of long-term Power Spectral Densities (PSDs), and another the instantaneous spectral characteristics of the data. For both of these efforts, the Lomb-Scargle method was used, due to the need for equivalent results obtained from data characterized by non-uniform sampling, that also varies strongly with altitude and time.
WP 3 encompassed two tasks related to determining the propagation parameters associated with AGW induced TIDs, and determining the statistical distribution of these parameters.
WP 4 encompassed three tasks related to investigating possible correlations between ionospheric disturbances and geomagnetic activity. Two approaches were found to be successful in this: First, using the integral of the PSDs determined as part of WP 2 and the Kp index, the correlation between the dominant spectrum of ionospheric disturbances and geomagnetic activity was investigated for the entire 7-year period at Tromso. Second, by using additional data from the NOAA-NCEI ionosonde database, the ionospheric response to a series of geomagnetic events was investigated.
WP 5 encompassed three tasks associated with dissemination and communication activities. As part of this, one paper was published in the Journal of Geophysical Research: Space Physics, one manuscript is in review at the journal Surveys in Geophysics and an additional manuscript is in development. Additionally, three conference presentations were given, with several more planned as soon as travel restrictions and other pandemic related problems will no longer be an issue. Finally, a number of public presentations and demonstrations were performed involving the broader public, and more have been planned to take place as soon as public gatherings can safely resume.
Throughout the implementation of the project, extensive experience was gained in analyzing and processing Dynasonde data for TID studies, as well as in the complementary techniques that were employed and implemented, such as spectral analysis methods and statistical analysis techniques. The results obtained are at the forefront of the field, in particular those showing the correlation between geomagnetic activity and ionospheric variability in a statistical sense, for long periods of time characterized by only a small number of geomagnetic storms.
One of the unexpected products of this project was the large database of results describing TIDs detected using the Tromsø Dynasonde. This is intended as a resource for use in the study of AGW and TID activity by other scientists and interested parties. More than 200000 files were generated, containing different data types in .mat format. These will be available upon request, while sample files are hosted on the project website. These include the dynasonde data on a constant height grid, the results of the detrending procedure ((N_e ) ̅ and N_e^'), the results of the spectral analysis, and the wavevector components. Additionally, the catalogues of figures describing the characteristics of the dominant wave activity are available, with one figure per month for the time-domain data, the height stratified PSD and the distribution of the TID propagation parameters.
The work revealed that the solar-wind – magnetosphere – ionosphere coupling has a complex impact on the high-latitude thermosphere-ionosphere, influencing not just the background structure, composition and circulation, but also the small-scale structure through the generation of AGWs. This likely acts as an added source of energy and momentum, with a potential global impact as high-latitude AGWs propagate towards the middle and low-latitude sectors.
Regarding the broader impact for the general public, several public demonstrations and presentations were made in the past 2 years, involving interested scientists, young students or simply general audiences interested in science. Despite a great start in 2019, restrictions on public gatherings have made such events impossible in 2020 and very difficult in 2021. Nevertheless, the public interest has surpassed all expectations, particularly due to the availability of a in-house built Planeterrella experimental setup that functions as an invaluable illustrator of the solar wind-magnetosphere-ionosphere coupling. As soon as the pandemic situation sufficiently improves in Romania, a number of public demonstrations are already planned, involving several schools that would otherwise have difficulties participating in such events.
One of the unexpected products of this project was the large database of results describing TIDs detected using the Tromsø Dynasonde. This is intended as a resource for use in the study of AGW and TID activity by other scientists and interested parties. More than 200000 files were generated, containing different data types in .mat format. These will be available upon request, while sample files are hosted on the project website. These include the dynasonde data on a constant height grid, the results of the detrending procedure ((N_e ) ̅ and N_e^'), the results of the spectral analysis, and the wavevector components. Additionally, the catalogues of figures describing the characteristics of the dominant wave activity are available, with one figure per month for the time-domain data, the height stratified PSD and the distribution of the TID propagation parameters.
The work revealed that the solar-wind – magnetosphere – ionosphere coupling has a complex impact on the high-latitude thermosphere-ionosphere, influencing not just the background structure, composition and circulation, but also the small-scale structure through the generation of AGWs. This likely acts as an added source of energy and momentum, with a potential global impact as high-latitude AGWs propagate towards the middle and low-latitude sectors.
Regarding the broader impact for the general public, several public demonstrations and presentations were made in the past 2 years, involving interested scientists, young students or simply general audiences interested in science. Despite a great start in 2019, restrictions on public gatherings have made such events impossible in 2020 and very difficult in 2021. Nevertheless, the public interest has surpassed all expectations, particularly due to the availability of a in-house built Planeterrella experimental setup that functions as an invaluable illustrator of the solar wind-magnetosphere-ionosphere coupling. As soon as the pandemic situation sufficiently improves in Romania, a number of public demonstrations are already planned, involving several schools that would otherwise have difficulties participating in such events.