Earthquake Precursors in the Atmosphere and Ionosphere: New Concepts

Preface
Introduction: The Basics of the Lithosphere‒Atmosphere‒Ionosphere Coupling (LAIC) Model
	What Does the Coupling Mean?
	LAIC Model Schematic Presentation
	References
Contents
1 Near-Ground Processes as a Result of Air Ionization
	1.1 Radon as a Main Source of Air Ionization in Seismically Active Areas
		1.1.1 Radon Production, Transport and Gas Migration
		1.1.2 Radon Spatial Distribution Within Earthquake Preparation Zone
		1.1.3 Is It Possible to Identify Precursory Radon Variations?
	1.2 Ionization and Near-Ground Plasmachemistry
		1.2.1 Peculiarities of Ionization of Atmospheric Air: Track Structure
		1.2.2 Low Degree of Ionization: The Model of Stable Ions Formation in the Low Layers of the Atmosphere
		1.2.3 Analysis of Processes of the Main Negative Ions Formation in the Lower Atmosphere
		1.2.4 Analysis of Main Positive Ions Formation Processes in the Lower Atmosphere
		1.2.5 The Concept of Neutral Ion Clusters in Air
		1.2.6 Condensation Versus Ion Hydration
	1.3 Latent Heat as a Result of Ion Hydration, and the Main Source of Thermal Anomalies and Air Humidity Variations
		1.3.1 Atmospheric Chemical Potential as Indicator of Radon Activity and Thermodynamic Instability in the Atmosphere
	References
2 Earthquake Precursory Phenomena in the Atmosphere
	2.1 Thermal Balance of Ionization and Meteorological Phenomena
		2.1.1 Energetics of Radon Emanation
		2.1.2 Energetics of Ionization and IIN in the Boundary Layer
	2.2 Thermal Convection and Formation of Linear Cloud Anomalies or EQ Clouds
		2.2.1 Possible Physical Mechanism of LCA Formation
	2.3 Latent Heat (LH) in the Atmosphere Associated with Earthquake Processes
		2.3.1 Experimental Estimation of LH Associated with M9.3 on December 26th, 2004 and M8.5 on March 28th, 2005 Near the Sumatra Earthquakes
		2.3.2 Pre-earthquake LH Anomalies Associated with the 2011 M9.0 Tohoku Earthquake in Japan
		2.3.3 LH Energies Associated with the 2011 M9.0 Tohoku Earthquake in Japan
	2.4 Outgoing Long-Wave Radiation (OLR) as a Powerful Indicator of an Approaching Earthquake
		2.4.1 Main Techniques for Measurement and Identification of ETA
		2.4.2 Physical Nature of ETA
		2.4.3 ETA Assessment Based on OLR Data
		2.4.4 Revealing Pre-earthquake ETA in the Atmosphere Associated with 2015 M7.8 and M7.3 Events in Nepal
	2.5 Jet-Stream Change as an Indicator of Earthquake Processes
	2.6 Reversed Cascade Process as a Possible Mechanism of Anomalous OLR Spots Formation
	References
3 Earthquake Precursors in the Ionosphere
	3.1 Ionization, Atmospheric Electricity, and Possible Mechanisms of Anomalous Electric Field Generation
		3.1.1 Electrode Effect
		3.1.2 Electric Field Reversals
		3.1.3 Anomalous Fluctuations of Electric Field
		3.1.4 Active Experiments
		3.1.5 Cloud-Like Charge Separation and Possibility of Pulsed Emission from Aerosol Layers
	3.2 The Global Electric Circuit
	3.3 Planetary Boundary Layer and Atmospheric Electricity
		3.3.1 Local Time Dependence of Ionospheric Precursors
		3.3.2 Possible Thermal Instability in the Boundary Layer
		3.3.3 Conductivity Changes in the Boundary Layer and the Lower Troposphere Under the Action of Ionization
	3.4 Electric Field Penetration into the Ionosphere
		3.4.1 Penetration of an Electric Field of Seismic Origin into the Ionosphere
		3.4.2 Calculation of the Electric Field in the Ionosphere (Cylindrical Source)
		3.4.3 Effects of the Anomalous Electric Field in the E-Region
		3.4.4 Formation of Sporadic Layers in the E-Region
		3.4.5 Electric Field Effects in the F-Region
		3.4.6 Calculation of the Electric Field for Elongated Sources
	3.5 Ionospheric Potential and its Effects in Equatorial Anomaly
		3.5.1 Ion Mobility and Air Conductivity
		3.5.2 Positive and Negative Conductivity Changes in the Troposphere and the Global Electric Circuit
		3.5.3 Mechanism of Ionospheric Anomaly Formation in Low-Latitude Ionosphere Due to Changes of Air Conductivity in the Boundary Layer
	3.6 Magnetospheric Effects
		3.6.1 Seismically Induced Particle Precipitation From the Magnetosphere
		3.6.2 From the Magnetosphere to D-Region
	3.7 The Physical Mechanism of  Seismo-ionospheric Coupling: A Never-Ending Road
	References
4 Multiparameter Approach and LAIC Validation
	4.1 Synergy of Atmospheric and Ionospheric Effects Before Earthquakes
		4.1.1 The LAIC Model as a Complex System
		4.1.2 Trying to Catch the “Arrow of Time”: Integrated Parameters
	4.2 Some Major Seismic Events and Registered Pre-earthquake Atmospheric Signatures
		4.2.1 M6.8, 16 July 2007, Niigata Chuetsu-Oki, Japan
		4.2.2 M7.6, 8 October 2005, Near the Coast of Central Peru
		4.2.3 M7.9, 12 May 2008, Eastern Sichuan, China
		4.2.4 M6.3, 6 April 2009, L’Aquila, Italy
		4.2.5 M7.1, 12 January 2010, Haiti
		4.2.6 M6, 21 February 2011, Christchurch, NZ
		4.2.7 M9, 11 March 2011, Near the East Coast of Honshu, Japan
		4.2.8 M7.7, 24 September 2013, Balochistan, Pakistan
		4.2.9 M8.2, 1 April 2014, Iquique, Chile
		4.2.10 M7.8, 25 April 2015, Nepal, M7.3 of 12 May 2015, Nepal
	4.3 Identification Technique for Short-Term Precursors
		4.3.1 Methods for Detection of Atmospheric/ionospheric Anomalies
		4.3.2 The Machine-Learning Approach to Precursor Identification
		4.3.3 The Integrated Approach to Precursor Identification
	4.4 Statistical Studies of Pre-earthquake Atmospheric and Ionospheric Anomalies
		4.4.1 Thermal Radiation Anomalies (TRA)
		4.4.2 Seismo-Ionospheric Anomalies
		4.4.3 Verification of Ionospheric Precursory Phenomena with DEMETER
	References
5 Future Developments
	5.1 Naturally Stimulated Seismic Activity
		5.1.1 Mechanical Triggers
		5.1.2 Electromagnetic Triggers
		5.1.3 Gravitational Triggering
		5.1.4 Solar and Geomagnetic Activity: Magnetic Storms and Earthquakes
		5.1.5 Induced and Anthropogenic Earthquakes
	5.2 Nuclear Tests and Seismicity
	5.3 General Concluding Remarks
	References