Analysis of close conjunctions between dayside polar cap airglow patches and flow channels by all-sky imager and DMSP ...

• Main Authors: Wang, Boyi, Nishimura, Yukitoshi, Lyons, Larry, Zou, Ying, Carlson, Herbert, Frey, Harald, Mende, Stephen
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: figshare 2016
• Subjects: Biophysics; Space Science; Medicine; Cell Biology; Molecular Biology; Neuroscience; Physiology; FOS Biological sciences; Pharmacology; Evolutionary Biology; Environmental Sciences not elsewhere classified; Chemical Sciences not elsewhere classified; Astronomical and Space Sciences not elsewhere classified; Cancer; Infectious Diseases; FOS Health sciences; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.3629051.v1; https://springernature.figshare.com/collections/Analysis_of_close_conjunctions_between_dayside_polar_cap_airglow_patches_and_flow_channels_by_all-sky_imager_and_DMSP/3629051/1

Abstract Recent imager and radar observations in the nightside polar cap have shown evidence that polar cap patches are associated with localized flow channels. To understand how flow channels propagate from the dayside auroral oval into the polar cap, we use an all-sky imager in Antarctica and DMSP (F13, F15, F16, F17 and F18) to determine properties of density and flows associated with dayside polar cap patches. We identified 50 conjunction events during the southern winter seasons of 2007–2011. In a majority (45) of events, longitudinally narrow flow enhancements directed anti-sunward are found to be collocated with the patches, have velocities (up to a few km/s) substantially larger than the large-scale background flows (~500 m/s) and have widths comparable to patch widths (~400 km). While the patches start with poleward moving auroral forms (PMAFs) as expected, many PMAFs propagate azimuthally away from the noon over a few hours of MLT, resulting in formation of polar cap patches quite far away from the ...