Anomalies of total column CO and O&amp;lt;sub&amp;gt;3&amp;lt;/sub&amp;gt; associated with great earthquakes in recent years

Y Cui,J Du,Y Sun,D Zhang

doi:10.5194/nhess-13-2513-2013

Abstract

Abstract. Variations of total column CO and O3 in the atmosphere over the epicenter areas of 35 great earthquakes that occurred throughout the world in recent years were studied based on the hyper-spectrum data from Atmospheric Infrared Sounder (AIRS). It was found that anomalous increases of CO and/or O3 concentrations occurred over the epicenter areas of 12 earthquakes among the 35 studied ones. However, increases in both CO and O3 concentrations were found for 6 earthquakes. The O3 anomalies appeared in the month when the earthquake occurred and lasted for a few months, whereas CO anomalies occurred irregularly. The duration of CO and O3 anomalies related to the earthquakes ranged from 1 to 6 months. The anomalies of CO concentration related to the earthquake can be mainly attributed to gas emission from the lithosphere and photochemical reaction, while the anomalous increases in O3 concentration can be mainly due to the transport of O3-enriched air and photochemical reaction. However, more work needs to be done in order to understand the mechanism of the CO and O3 anomalies further.

Highlights

Emissions of Rn, He and greenhouse gases (CO, CO2, CH4, etc) from the fault zones to the atmosphere, especially from the structurally weak zones such as intersections or bends of faults, can be enhanced by the action of tectonic stress
The anomaly intensities of GCO and GO3 for one pixel related to 12 earthquakes ranged from 1.48 × 1017 to 2.79 × 1017 molecules cm−2 and from 28 to 68 Dobson units (DUs), respectively
The beginnings and durations of CO and O3 anomalies were different from case to case (Table 2) because the photochemical reactions producing CO and O3 and the dynamical disturbances took place asynchronously

Summary

Introduction

Emissions of Rn, He and greenhouse gases (CO, CO2, CH4, etc) from the fault zones to the atmosphere, especially from the structurally weak zones such as intersections or bends of faults, can be enhanced by the action of tectonic stress. The correlation between 8 yr measurements of radon flux in gravel and hundreds of earthquakes (4.6 ≥ ML ≥ 0) indicated that earthquakes preferentially occurred in three pull-apart grabens of the Dead Sea rift valley within the time interval of the first 3 days after the start time of 110 Rn anomalies (Steinitz et al, 2003), indicating gas emission from solid earth to the atmosphere during seismic activity. It was summarized that terrestrial gas anomalies, such as Rn, He, H2, Hg and CO2, for the duration of a few hours to dozens of months related to the large earthquakes were found in the areas where the epicentral distances of hundreds of kilometers (larger for larger earthquakes, up to 1000 km or more for magnitude 8), and the amplitude of the anomalies did not show consistent correlation with either earthquake magnitude or epicentral distance (King, 1986; King et al, 2006). Numbers of pre-earthquake anomalies of the thermal, surface latent heat flux and outgoing long-wave radiation apparently resulted from the earthquake-related gas emission from the lithosphere (Tronin, 2000, 2002; Dey and Singh, 2003; Tronin et al, 2006; Ouzounov et al, 2007)

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