Journal ArticleRadar Observations of Flows Leading to Longitudinal Expansion of Substorm Onset Over AlaskaLyons, Larry R.; Liu, Jiang; Nishimura, Yukitoshi; Wang, Chih‐Ping; Reimer, Ashton S.; Bristow, William A.; Hampton, Don L.; Shi, Xueling; Varney, Roger H.; Donovan, Eric F.null2021-02-0110225297Journal of Geophysical Research: Space Physics12622169-9380https://doi.org/10.1029/2020JA0281481907698; 1907483National Science Foundation