Using Principal Component Analysis to Characterize the Variability of VLF Wave Intensities Measured by a Low-Altitude Spacecraft and Caused by Interplanetary Shocks

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F21%3A00543236" target="_blank" >RIV/68378289:_____/21:00543236 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11320/21:10431313

Výsledek na webu

<a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021JA029158" target="_blank" >https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021JA029158</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2021JA029158" target="_blank" >10.1029/2021JA029158</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Using Principal Component Analysis to Characterize the Variability of VLF Wave Intensities Measured by a Low-Altitude Spacecraft and Caused by Interplanetary Shocks

Popis výsledku v původním jazyce

Very low frequency wave intensity measurements provided by the French low-altitude DEMETER spacecraft are studied using the principal component analysis (PCA). We focus on both the physical interpretation of the first two principal components and their application to real physical problems. Variations of the first principal component (PC1) coefficients due to the geomagnetic activity and seasonal/longitudinal changes are studied. It is shown that their distribution corresponds to the wave intensity dependences obtained in previous studies. Moreover, the variations of PC1 coefficients around interplanetary shock arrivals are analyzed. The study is performed for fast forward (FF), fast reverse, slow forward, and slow reverse shocks separately. It shows that the most significant effect on the wave intensity is displayed in the FF case. Furthermore, it turns out that the wave intensity variations depend on the wave intensity detected before the shock arrival. Finally, the shock strength and interplanetary magnetic field orientation are also important. The performed analysis shows that PCA can be successfully applied to characterize large data sets of spacecraft measurements by limited sets of numbers-principal component coefficients (typically first one or two are enough), which still maintain a sufficient amount of information.

Název v anglickém jazyce

Using Principal Component Analysis to Characterize the Variability of VLF Wave Intensities Measured by a Low-Altitude Spacecraft and Caused by Interplanetary Shocks

Popis výsledku anglicky

Very low frequency wave intensity measurements provided by the French low-altitude DEMETER spacecraft are studied using the principal component analysis (PCA). We focus on both the physical interpretation of the first two principal components and their application to real physical problems. Variations of the first principal component (PC1) coefficients due to the geomagnetic activity and seasonal/longitudinal changes are studied. It is shown that their distribution corresponds to the wave intensity dependences obtained in previous studies. Moreover, the variations of PC1 coefficients around interplanetary shock arrivals are analyzed. The study is performed for fast forward (FF), fast reverse, slow forward, and slow reverse shocks separately. It shows that the most significant effect on the wave intensity is displayed in the FF case. Furthermore, it turns out that the wave intensity variations depend on the wave intensity detected before the shock arrival. Finally, the shock strength and interplanetary magnetic field orientation are also important. The performed analysis shows that PCA can be successfully applied to characterize large data sets of spacecraft measurements by limited sets of numbers-principal component coefficients (typically first one or two are enough), which still maintain a sufficient amount of information.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Geophysical Research-Space Physics

ISSN

2169-9380

e-ISSN

2169-9402

Svazek periodika

126

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

14

Strana od-do

e2021JA029158

Kód UT WoS článku

000657463000062

EID výsledku v databázi Scopus

2-s2.0-85107073084