TY - JOUR
T1 - The ROC Curve Examination on Traveling Ionospheric Disturbances in FORMOSAT-7/COSMIC-2 IVM Ion Density Triggered by the 15 January 2022 Tonga Volcanic Eruption
AU - Liu, Jann Yenq
AU - Cheng, Ching Chung
AU - Lee, Po Han
AU - Liu, Tien Chi
AU - Lin, Chi Yen
AU - Lin, Charles Chien Hung
AU - Kan, Kevin
N1 - Publisher Copyright:
© 2024. American Geophysical Union. All Rights Reserved.
PY - 2024/10
Y1 - 2024/10
N2 - The receiver operating characteristic (ROC) and the area under the curve (AUC), initially developed for signal processing and psychology, are a test for assessing the performance of a binary classification problem at varying threshold values. The ion density (Ni) observed by FORMOSAT-7/COSMIC-2 is used to study traveling ionospheric disturbances (TIDs) triggered by the 15 January 2022 Tonga volcanic eruption. We examine parameters of Ni, differential Ni, and standard deviation Ni (STD_Ni) in January 2022, simulate TID wavefronts traveling with various speeds from 10 to 1,000 m/s, and apply the ROC curve to globally identify the significance of TIDs in STD_Ni triggered by the volcanic eruption. ROC and AUC results show that in addition to TIDs related to tsunami/tropospheric Lamb waves and a series of fast-moving waves with propagation speeds of 180–350 and 450–600 m/s, respectively, those long-lasting low-speeds less than 70 m/s and high-speeds about 690, 860, and 990 m/s meet 95% statistical significance, which confirms TIDs being detected. These show that the FORMOSAT-7/COSMIC-2 ion density can be used to globally detect various TIDs triggered by the Tonga volcanic eruption. The ROC test results also show a potential use case for detecting other geophysical signals in future applications.
AB - The receiver operating characteristic (ROC) and the area under the curve (AUC), initially developed for signal processing and psychology, are a test for assessing the performance of a binary classification problem at varying threshold values. The ion density (Ni) observed by FORMOSAT-7/COSMIC-2 is used to study traveling ionospheric disturbances (TIDs) triggered by the 15 January 2022 Tonga volcanic eruption. We examine parameters of Ni, differential Ni, and standard deviation Ni (STD_Ni) in January 2022, simulate TID wavefronts traveling with various speeds from 10 to 1,000 m/s, and apply the ROC curve to globally identify the significance of TIDs in STD_Ni triggered by the volcanic eruption. ROC and AUC results show that in addition to TIDs related to tsunami/tropospheric Lamb waves and a series of fast-moving waves with propagation speeds of 180–350 and 450–600 m/s, respectively, those long-lasting low-speeds less than 70 m/s and high-speeds about 690, 860, and 990 m/s meet 95% statistical significance, which confirms TIDs being detected. These show that the FORMOSAT-7/COSMIC-2 ion density can be used to globally detect various TIDs triggered by the Tonga volcanic eruption. The ROC test results also show a potential use case for detecting other geophysical signals in future applications.
KW - FORMOSAT-7/COSMIC-2
KW - ion density
KW - receiver operating characteristic curve
KW - thermospheric lamb wave
KW - Tonga volcano
KW - tropospheric lamb wave
UR - http://www.scopus.com/inward/record.url?scp=85205990459&partnerID=8YFLogxK
U2 - 10.1029/2024JA033198
DO - 10.1029/2024JA033198
M3 - 期刊論文
AN - SCOPUS:85205990459
SN - 2169-9380
VL - 129
JO - Journal of Geophysical Research: Space Physics
JF - Journal of Geophysical Research: Space Physics
IS - 10
M1 - e2024JA033198
ER -