Possible Formation Mechanisms of Earthquake Ionospheric Precursors
Possible Formation Mechanisms of Earthquake Ionospheric Precursors Klimenko M.V. 1,2 ,Klimenko V.V. 1 , Bryukhanov V.V. 2 , Pulinets S.A. 3,4 1 N.V. Pushkov IZMIRAN Western Department, Kaliningrad, Russia, [email_address] 2 Kaliningrad State Technical University, Kaliningrad, Russia, [email_address] 3 Fedorov Institute of Applied Geophysics, Moscow Russia 4 Institute of Space Research, Moscow Russia IDRC Davos 2010 INTERNATIONAL DISASTER AND RISK CONFERENCE
Ionospheric Δ f 0 F 2 anomalies with combination of ground-based data and satellite data ( Pulinets et al, 2004 ) Alaska earthquake M8.5, on 27 March, 1964. Alouette-1 Satellite and ionosondes (quake in high latitude) Irpinia , M6.9, on 23 November, 1980. Intercosmos-19 Satellite (quake in middle latitude) New Guinea M7.3, at 1956UT,on 16 July 1980. Intercosmos-19 Satellite (quake in low latitude/ equator) 29 hours before the event 18 hours after the event Conjugated modified area 24 hours before the event 24 hours after the event 48 hours before the event Review of the typical earthquakes
Ionospheric precursors <ul><li>Good Alaska Earthquake in 1964 (M W = 9.2) </li></ul><ul><li>Davies and Baker , 1965; Leonard and Barnes, 1965 </li></ul><ul><li>Intensive searches </li></ul><ul><li>Liperovsky et al. , 1992; Hayakawa , 1999; Pulinets and Boyarchuk , 2004; Liperovsky , 2008 </li></ul><ul><li>GPS TEC before mid-latitude earthquake </li></ul><ul><li>Oraevsky, 2000; Liu et al., 2004; Zakharenkova et al., 2006a,b </li></ul><ul><li>Vertical transport of F2 -region ionosphere plasma under action of the zonal electric field is probable mechanism of formation of TEC disturbed areas observable prior strong earthquakes </li></ul><ul><li>Namgaladze , 2007; Namgaladze et al ., 2007 b . </li></ul>
<ul><li>Strong arguments in favor of this hypothesis: </li></ul><ul><li>The geomagnetic conjugacy of the ionospheric precursors Pulinets et al., 2003 </li></ul><ul><li>Effects in equatorial anomaly Depueva and Ruzhin, 1995; Zakharenkova et al., 2006a </li></ul><ul><li>Model calculation results Namgaladze et al ., 2007; Zolotov et al ., 2008; Klimenko and Klimenko , 2008; Namgaladze et al ., 2009 </li></ul> = 10 kV (high- and mid-latitude earthquake) = 5 kV (near-equatorial earthquake) Additional Electric Field
Left panel: Zonal electric field (top) and TEC (middle) deviations simulated for the additional eastward electric field at Rome and GPS TEC deviations one day prior to earthquake in Japan on September 25, 2003 (bottom). Right panel: The same as in the left panel for the additional westward electric field (top and middle) and for earthquake in Turkey on August 17, 1999 (bottom). Mid-Latitude Earthquakes Electric Field Effects
Near-Equatorial Earthquakes Vanimo Earthquake on 16.07.1980 Peru Earthquake
Question: How such electric fields can arise in the ionosphere prior earthquakes? <ul><li>Answer: </li></ul><ul><li>Penetration from below. </li></ul><ul><li>Generation by Internal Gravity Waves (IGW) </li></ul><ul><li>Klimenko et al., 2009 </li></ul>The polarizing electric fields generated by IGW Yokoyama et al., 2004 Physical models of lithosphere-atmosphere-ionosphere coupling prior earthquakes are reviewed Liperovsky et al., 1992; Pulinets and Boyarchuk, 2004; Liperovsky, 2008
Some basic hypotheses of lithosphere-atmosphere-ionosphere coupling 1. The IGW with the period ~1-3 hours Pertsev and Shalimov , 1996 2. The IGW with the period from several minutes up to tens minutes Mareev et al., 2002; Molchanov, 2004 3. Seismogenic electric field with amplitude from units up to tens mV/m Chmyrev et al ., 1989 ; Sorokin and Chmyrev, 1999; Grimalsky et al ., 2003 ; Pulinets and Boyarchuk, 2004 4. The abnormal electro-magnetic fields and emissions Hayakawa and Fujinawa, 1994; Hayakawa and Molchanov, 2002
Geographical position of an epicentre (triangle) and the GPS stations nearest to epicentre. Geomagnetic conditions 1-10 January 2006. Daily ТЕС variations for stations ORID, TUBI, MATE and NOT1 for the period on 3–9 January 2006 (1 TECU = 10 16 el m –2 ). A thin line is current variation of ТЕС , and a thick line is a median. The arrow notes the moment of earthquake. Greece Earthquake on 08.01.2006
The model GSM TIP was described in details in Namgaladze et al., 1988 . In this model the numerical decision of the hydrodynamics equations for multicomponent gas mixture, consisting of neutral (O 2 , N 2 , O, H), and charged (the molecular ions O 2 + , NO + , atomic ions O + , H + , and electrons) particles is realized. In the model GSM TIP by the self-consistent manner the thermospheric winds from the equations of movement of neutral gas and the electric fields of dynamo and magnetospheric origin are calculated. All model equations are solved by finite-difference method. The model is added by the new block of calculation of electric fields Klimenko et al., 2006, 2007 . M odel GSM TIP B rief D escription In this study the calculations were carried out with use of the G lobal S elf-consistent M odel of the T hermosphere, I onosphere and P rotonosphere ( GSM TIP ), developed in WD IZMIRAN
The IGWs were set on the bottom boundary of the thermosphere at height of 80 km under following formulas: Internal Gravity Waves (IGWs) n (O 2 ) = n (O 2 ) 0 A 10 –2 sin (2 t / ), m –3 n (N 2 ) = n (N 2 ) 0 A 10 –2 sin (2 t / ), m –3 n (O) = n (O) 0 A 10 –2 sin (2 t / ), m –3 T n = T n 0 A 4 10 –3 sin (2 t / ), K V nΘ = A sin (2 t / ), m s –1 V nΛ = A sin (2 t / ), m s –1 , where A = 10 m s –1 – amplitude of IGW (t his kind of amplitude are also obtained Sumatra tsunami ( Occhipinti et al., 2006, 2008 , Alam Kherani et al., 2009 ) ), = 600 s – period of IGW, t – Universal Time in s, n (O 2 ) 0 = 7.4 10 19 m –3 , n (N 2 ) 0 = 3.0 10 20 m –3 , n (O) 0 = 2.4 10 16 m –3 , T n 0 = 188 K – background values of concentration of molecular oxygen, molecular nitrogen, atomic oxygen and temperatures of neutral gas, accordingly. The effects of IGW created by solar terminator Karpov and Bessarab, 2008
Daily variations of zonal (top left) and meridional (top right) component of the electric field, critical frequency of the F2 -layer (bottom left) and the total electron content (bottom right), calculated above earthquake epicentre with ( dotted lines ) and without (solid lines) taking into account IGW.
Left (middle) panel – zonal electric field deviation ( TEC deviation) at the different UT moments modelled with IGWs. Right panel – experimental maps of GPS TEC deviations IGW effects and GPS TEC
The Penetration of Vertical Electric Field from the Atmosphere into the Ionosphere, Appearance of Zonal Electric Field and it’s Superposition with IGWs Daily variations of zonal (top left) and meridional (top right) component of the electric field, critical frequency of the F2 -layer (bottom left) and the total electron content (bottom right), calculated above earthquake epicentre: black circles – quiet conditions, dark blue circles – with additional electric field (E), red circles – with taking into account IGW and E.
Calculated deviations zonal electric field in geographic Cartesian coordinate system for the different time moments obtained with taking into account of additional IGWs, electric field generated in epicentre region and they superposition. E E&IGW IGW
SUMMARY (1) T he analysis of our model calculation results testifies in favour of hypothesis about seismogenic zonal electric field in the ionosphere appearing in the near-epicentral area and caused observable changes in ionospheric electron concentration prior to strong earthquakes. Due to local character of large-scale ionospheric precursors, as it formation mechanisms can consider: 1) the small-scale IGWs and/or 2) the seismogenic electric field in the ionosphere. We used the numerical experiments for reproduction of observed changes in the ionosphere prior to strong mid-latitude earthquake in Greece. We consider the three variants of seismogenic sources input: a) the small-scale IGWs near to epicenter area b) the penetration of vertical electric field from the atmosphere into the ionosphere in the epicentral area c) the superposition of the a) and b). It is possible to note a good agreement of calculation results and experiment. This report is presented owing to financial support from LOC IDRC 2010.
SUMMARY (2) This report is presented owing to financial support from LOC IDRC 2010. Varying, switching on and off the seismogenic IGWs and vertical electric field, it is possible to achieve similarity of calculation results and the given observation before strong earthquakes. The given research can be considered as the next step to understanding the formation mechanisms of ionosphere precursors of strong earthquakes. However, the existence of ionospheric earthquake precursors demands the experimental acknowledgement. This is possible only by means of increase in volume of appropriate experimental data and their statistical importance.
Geomagnetic conditions 1-13 May 2008 . WENCHUAN Earthquake on 12.05.2008 Maps based on model calculation results for 08:00 UT. Top – 1 and 2 day calculation results with E vertical. Bottom – 3 and 4 day calculation results with E vertical and IGWs. IONEX data at 08:00 UT Map based on the GPS TEC measurements.
Two-dimensional maps for differential TEC ( DTEC ) on 9 May 2008. Left – Chinese GPS data from 0430 to 0930 UT. Middle – GPS TEC measurements from 0200 to 1000 UT. Right – TEC deviations from 0200 to 1000 UT modelled with E vertical. The star represents the epicenter.