Japan Geoscience Union Meeting 2018

Presentation information

[EE] Oral

P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM10] Coupling Processes in the Atmosphere-Ionosphere System

Mon. May 21, 2018 3:30 PM - 5:00 PM 304 (3F International Conference Hall, Makuhari Messe)

convener:Huixin Liu(Earth and Planetary Science Division, Kyushu University SERC, Kyushu University), Loren Chang(Institute of Space Science, National Central University), Yuichi Otsuka(名古屋大学宇宙地球環境研究所), Chairperson:Liu Huixin(Kyushu University, Japan)

3:30 PM - 3:45 PM

[PEM10-06] Substorm Modulation of Lightning Occurrence over North America

*Omar Angelo Nava1, Bea Gallardo-Lacourt2 (1.Air Force Institute of Technology, 2.University of Calgary)

Keywords:substorm, MIT coupling, lightning, National Lightning Detection Network, SuperMAG, auroral electrojet

The response of lightning rates over North America to the occurrence of substorms is investigated using superposed epoch analysis. Composites of daily National Lightning Detection Network (NLDN) data and SuperMAG substorm events from 1990-2012 indicate a statistically significant increase in lightning strikes across North America, especially at higher latitudes. Strikingly, these results suggest a strong connection between the upper atmosphere and cloud electrification processes in the lower troposphere, most likely through an enhancement of the auroral electrojet. It is hypothesized that increased conductivities (i.e., electron densities) in the E-layer associated with the global atmospheric electrical circuit result in favorable conditions for lightning initiation. Because magnetosphere-ionosphere-thermosphere (MIT) coupling has been poorly addressed, analysis of the electrodynamic connection between the troposphere and upper atmosphere has important implications for both space physics and atmospheric science communities.