A Statistical Analysis of Multiple Characteristics of Subauroral Polarization Streams During 15 Intense Magnetic Storms
Abstract
Subauroral polarization streams (SAPS) are persistent westward plasma drift equatorward of the auroral oval in the dusk‐midnight sector during geomagnetic storms. Past research has studied the dependence of SAPS latitude on Dst and the seasonal and diurnal variations of SAPS. However, other characterizations of the SAPS structure are largely unexplored. In this study, a new method is developed for SAPS determination which does not require manual analysis. The method is then applied to 15 intense magnetic storms between 2000 and 2015 using data measured by the Defense Meteorological Satellite Program satellites, and the SAPS are characterized at every hour of the storm by (a) magnetic latitude, (b) peak velocity, (c) average velocity, and (d) the integration of velocity over the width of the SAPS, denoted Area. The following statistical analysis of these results demonstrates that all four characteristics have strong correlations with Dst and weak‐to‐moderate correlations with the interplanetary magnetic field. SAPS local time dependence and main phase dependence are derived as well. Finally, a qualitative observation is discussed wherein Area varies with IMF Bz before Dst even begins to show evidence of a magnetic storm. These relationships provide new insight into SAPS evolution and its dependence on solar wind and magnetic activity.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2022
- Source ID
- 10.1029/2022ja030589
Entities
People
- Chao-Song Huang
- Jack R. Ross
Organizations
- Air Force Research Laboratory
- Yale University