Anomalous temperature regimen in the near-surface soil layer of Tlamacas hill and its relation to activity of Popocatépetl Volcano, Mexico

Anatolyi Kotsarenko,Vladimir Grimalsky,Vsevolod Yutsis,Yuryi Kotsarenko,Svetlana Koshevaya

doi:10.1051/bsgf/2020002

Abstract

This article describes anomalous changes in the diurnal behavior of the temperature measured in the near-surface soil at the Tlamacas monitoring site, Popocatépetl. Results of the statistical analysis show two essential changes for the temperature characteristics observed during the 2007–2009 (quiet volcano) and 2013–2014 (active volcano) monitoring periods. Under normal conditions, the absolute minimum daily temperature is observed at about 7:40 Local Time (LT) during sunrise for the atmosphere and, with a time delay, at about 8:30 LT, for soil measurements. The absolute temperature maximum is observed about 15:30 LT for the atmosphere and 16:30 LT for in-soil measurements. The dispersion of the residual temperature (24-h running trend of the temperature substituted) is 5.6 times lower for the 2013–2014 period in comparison with the 2007–2009 period. In other words, in 2013–2014, the temperature variability became 5.6 times lower that it was in 2007–2009.

Highlights

Monitoring of soil gas temperature, meteorological parameters, radon concentration and certain other associated physical characteristics is an important part of volcanology
In the absence of solar radiation, the temperature continuously decreased until the time of sunrise, so that the temperature minimum is observed about 7:40 Local Time (LT)
After that the temperature monotonically increased reaching its maximum at about 15:30 LT, after which the inclination of the Sun was such that solar radiation could no longer compensate the cooling of both the Earth’s surface and its atmosphere

Summary

Introduction

Monitoring of soil gas temperature, meteorological parameters, radon concentration and certain other associated physical characteristics is an important part of volcanology. Some previous investigations focused on soil temperatures in volcanic areas such as Stromboli, to investigate complex magmatic processes (Brusca et al, 2004; De Gregorio et al, 2007; Cigolini et al, 2009; Revil et al, 2011). The variation of temperature seems unremarkable, reaching maximum values in July–August and minimum values in December– February. A more detailed analysis of these data is warranted because the maximum temperature corresponds to the minimum pressure and radon concentration. The authors explain this phenomenon as being due to hydrothermal convection (Cigolini et al, 2009). Nick Varley and co-authors describe an explosion activity at Volcán de Colima derived from the rapid release of pressure and compare this process with other volcanoes, such as Santiaguito, Guatemala (Johnson et al, 2008), Sakurajima, Japan and Semeru, Indonesia (Iguchi et al, 2008) and Popocatépetl, Mexico (Varley et al, 2010)

Results

Discussion

Conclusion