Observations of midlatitude ionospheric instabilities generating meter-scale waves at the magnetic equator

摘要: [1] We present data from a spectacular low-latitude ionospheric event obtained using two imaging systems located on the Haleakala Volcano Maui, Hawaii (geographic: 20.7°N, 203.8°E; geomagnetic: 21.0°N, 271.9°E), and 50-MHz coherent scatter radar Christmas Island 2.0°N, 202.6°E; 3.1°N, 273.6°E). During event, structure is seen to develop in data, extending out of northern edge systems' fields view. Using dual-frequency Global Positioning System receivers throughout Hawaii, structures are evolve against an enhanced background total electron content caused by ongoing geomagnetic storm suggesting that pertinent features density enhancements, rather than depletions typify postsunset these instruments. Early evening, 3-m backscatter, as measured Island, occurs at magnetic equator field lines connected edges both sides this images. We discuss how multiple irregularity processes must be responsible for unusual facet individual can only explain development irregularities gradients one direction. conclude occur local, off-equator ionosphere. The larger-scale electric associated with map where they generate instabilities observed radar.