Statistical analysis and assessment of ionopheric anomalies before large earthquakes observed by ionosonde during 1958-2017,over Japan

Katsumi Hattori1, Sanaka Saito1, Chie Yoshino2 and Peng Han3, (1)Chiba University, Chiba, Japan, (2)Graduate School of Science, Chiba University, Chiba, Japan, (3)Southern University of Science and Technology, Department of Earth and Space Sciences, Shenzhen, China