Off‐great‐circle paths in transequatorial propagation: 2. Nonmagnetic‐field‐aligned reflections
Abstract
There is considerable evidence that plasma structure in nighttime equatorial F layer develops from large‐scale wave structure (LSWS) in bottomside F layer. However, crucial details of how this process proceeds, from LSWS to equatorial plasma bubbles (EPBs), remain to be sorted out. A major obstacle to success is the paucity of measurements that provide a space‐time description of the bottomside F layer over a broad geographical region. The transequatorial propagation (TEP) experiment is one of few methods that can do so. New findings using a TEP experiment, between Shepparton (SHP), Australia, and Oarai (ORI), Japan, are presented in two companion papers. In Paper 1 (P1), (1) off‐great‐circle (OGC) paths are described in terms of discrete and diffuse types, (2) descriptions of OGC paths are generalized from a single‐reflection to a multiple‐reflection process, and (3) discrete type is shown to be associated with an unstructured but distorted upwelling, whereas the diffuse type is shown to be associated with EPBs. In Paper 2 (P2), attention is placed on differences in east‐west (EW) asymmetry, found between OGC paths from the SHP‐ORI experiment and those from another near‐identical TEP experiment. Differences are reconciled by allowing three distinct sources for the EW asymmetries: (1) reflection properties within an upwelling (see P1), (2) OGC paths that depend on magnetic declination of geomagnetic field (B), and (3) OGC paths supported by non‐B‐aligned reflectors at latitudes where inclination of B is finite.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2016
- Source ID
- 10.1002/2016ja022404
Entities
People
- Mamoru Ishii
- Michi Nishioka
- Roland T. Tsunoda
- Tadahiko Ogawa
- Takashi Maruyama
- Takuya Tsugawa
- Tatsuhiro Yokoyama
- Trang Nguyen
Organizations
- Air Force Office of Scientific Research
- National Institute of Information and Communications Technology
- National Science Foundation
- SRI International