Precursor effect of March 11, 2011 off the coast of Tohoku earthquake on high and low latitude ionospheres and its possible disturbing mechanism

Oyama, K.-I.; Chen, C. H.; Bankov, L.; Minakshi, D.; Ryu, Kwang‐Sun; Liu, J. Y.; Liu, Huixin

doi:10.1016/j.asr.2018.12.042

Cited by 12 publications

(16 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the present study, we have confirmed the existence of the precursory AGW activity in the middle atmosphere before the EQ. Our finding not only evidence the AGW assumption by [ 85 ], but also complements one lacking piece in the LAIC studies of the 2011 Tohoku EQ.…”

Section: Discussionsupporting

confidence: 87%

“…In agreement with our promising AGW hypothesis of LAIC ( Section 1 ), Ref. [ 85 ] have reported the two-day oscillations in nighttime NmF2 (maximum electron density of the ionospheric F2 layer) during 6–11 March observed at several ionosonde stations of Khabarovsk, Beijing, Wakkanai, and Kokubunji. They have further explained the mechanism of the two-day oscillations by modifications of the ionospheric dynamo electric field, which are caused by the influences of AGW breaking on the middle atmospheric wind fields, and the acting waves originate from ground motions before the EQ.…”

Section: Discussionsupporting

confidence: 84%

See 1 more Smart Citation

Gravity Wave Activity in the Stratosphere before the 2011 Tohoku Earthquake as the Mechanism of Lithosphere-atmosphere-ionosphere Coupling

Yang

Hayakawa

2020

Entropy

View full text Add to dashboard Cite

The precursory atmospheric gravity wave (AGW) activity in the stratosphere has been investigated in our previous paper by studying an inland Kumamoto earthquake (EQ). We are interested in whether the same phenomenon occurs or not before another major EQ, especially an oceanic EQ. In this study, we have examined the stratospheric AGW activity before the oceanic 2011 Tohoku EQ (Mw 9.0), while using the temperature profiles that were retrieved from ERA5. The potential energy (EP) of AGW has enhanced from 3 to 7 March, 4–8 days before the EQ. The active region of the precursory AGW first appeared around the EQ epicenter, and then expanded omnidirectionally, but mainly toward the east, covering a wide area of 2500 km (in longitude) by 1500 km (in latitude). We also found the influence of the present AGW activity on some stratospheric parameters. The stratopause was heated and descended; the ozone concentration was also reduced and the zonal wind was reversed at the stratopause altitude before the EQ. These abnormalities of the stratospheric AGW and physical/chemical parameters are most significant on 5–6 March, which are found to be consistent in time and spatial distribution with the lower ionospheric perturbation, as detected by our VLF network observations. We have excluded the other probabilities by the processes of elimination and finally concluded that the abnormal phenomena observed in the present study are EQ precursors, although several potential sources can generate AGW activities and chemical variations in the stratosphere. The present paper shows that the abnormal stratospheric AGW activity has also been detected even before an oceanic EQ, and the AGW activity has obliquely propagated upward and further disturbed the lower ionosphere. This case study has provided further support to the AGW hypothesis of the lithosphere-atmosphere-ionosphere coupling process.

show abstract

Section: Discussionsupporting

confidence: 87%

Section: Discussionsupporting

confidence: 84%

Gravity Wave Activity in the Stratosphere before the 2011 Tohoku Earthquake as the Mechanism of Lithosphere-atmosphere-ionosphere Coupling

Yang

Hayakawa

2020

Entropy

View full text Add to dashboard Cite

show abstract

“…The interactions between tectonic plates could induce variations in electric and magnetic fields [11][12][13][14]. A strong location preference of the long-duration persistence of TEC anomalies may satisfy the persistence of regional electric field and/or an atmospheric gravity wave in the ionospheric dynamo region that induce TEC anomalies over a certain location through the dynamo process [15,16].…”

Section: Discussionmentioning

confidence: 99%

Global Distribution of Persistence of Total Electron Content Anomaly

Sun

Liu

et al. 2019

Atmosphere

View full text Add to dashboard Cite

To better understand the ionospheric morphology response to lithospheric activities, we study the global location preference of the positive and negative total electron content (TEC) anomalies persisting continuously for longer than 24 h at middle and low latitudes (within ±60° N geomagnetic latitudes). The TEC is obtained from the global ionospheric map (GIM) of Center for Orbit Determination in Europe (CODE) under the geomagnetic quiet condition of Kp ≤ 3o during the period of 2005 to 2018. There are a few (less than 4%) TEC anomalies that can persist over 24 h. The conjugate phenomenon is most significant in the eastern Asia to Australia longitudinal sector. The result shows the persistence of the positive TEC anomaly along the ring of fire on the western edge of the Pacific Ocean. The high persistence of the TEC anomalies at midlatitudes suggests that thermospheric neutral wind contributes to the anomaly formation.

show abstract

“…It is found that the Root-Mean-Square error (RMSE) of foF2 between COSMIC and ionosondes is around 0.5 MHz [29], the bias and std of NmF2 differences between COSMIC and ionosondes are 0.72% and 8.42%, respectively, and the bias and std of hmF2 are 2.80 and 11.46 km [30], respectively, which shows the great precision of COMSIC IRO data. Thanks to the large amount of timely and high-quality IRO products provided by COSMIC, the operationalization of occultation observation has been greatly promoted [20,31], and the IRO products of COSMIC have been widely used in ionospheric research, such as lower atmosphere-ionosphere coupling [32,33], ionospheric climatology study [1,[34][35][36][37], model assimilation [26,33,38,39], scintillation research [4,40,41], earthquake precursor study [42][43][44], and so on. It is worth mentioning that the globally distributed high-precision electron density profiles (EDPs) given by COSMIC provide unprecedented details for global ionospheric climatology study.…”

Section: Introductionmentioning

confidence: 99%

Comparison and Validation of the Ionospheric Climatological Morphology of FY3C/GNOS with COSMIC during the Recent Low Solar Activity Period

et al. 2019

View full text Add to dashboard Cite

With the accumulation of the ionospheric radio occultation (IRO) data observed by Global Navigation Satellite System (GNSS) occultation sounder (GNOS) onboard FengYun-3C (FY3C) satellite, it is possible to use GNOS IRO data for ionospheric climatology research. Therefore, this work aims to validate the feasibility of FY3C/GNOS IRO products in climatology research by comparison with that of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC), laying the foundation for its application in climatology study. Since previous verification works of FY3C/GNOS were done by comparison with ionosondes, this work matched NmF2/hmF2 of FY3C/GNOS and COSMIC into data pairs to verify the profile-level accuracy of FY3C/GNOS IRO data. The statistical results show that the overall correlation coefficients of both NmF2 and hmF2 are above 0.9, the overall bias and std of NmF2 differences between FY3C/GNOS and COSMIC are −2.19% and 17.48%, respectively, and the bias and std of hmF2 differences are −3.29 and 18.01 km, respectively, indicating a high profile-level precision consistency between FY3C/GNOS and COSMIC. In ionospheric climatology comparison, we divided NmF2/hmF2 of FY3C/GNOS into four seasons, then presented the season median NmF2/hmF2 in 5° × 10° grids and compared them with that of COSMIC. The results show that the ionospheric climatological characteristics of FY3C/GNOS and COSMIC are highly matched, both showing the typical climatological features such as equatorial ionosphere anomaly (EIA), winter anomaly, semiannual anomaly, Weddell Sea anomaly (WSA) and so on, though minor discrepancies do exist like the differences in magnitude of longitude peak structures and WSA, which verifies the reliability of FY3C/GNOS IRO products in ionospheric climatology research.

show abstract

Precursor effect of March 11, 2011 off the coast of Tohoku earthquake on high and low latitude ionospheres and its possible disturbing mechanism

Cited by 12 publications

References 29 publications

Gravity Wave Activity in the Stratosphere before the 2011 Tohoku Earthquake as the Mechanism of Lithosphere-atmosphere-ionosphere Coupling

Gravity Wave Activity in the Stratosphere before the 2011 Tohoku Earthquake as the Mechanism of Lithosphere-atmosphere-ionosphere Coupling

Global Distribution of Persistence of Total Electron Content Anomaly

Comparison and Validation of the Ionospheric Climatological Morphology of FY3C/GNOS with COSMIC during the Recent Low Solar Activity Period

Contact Info

Product

Resources

About