This study presents and discusses the results of soil radon monitoring at three different volcano sites and one reference site, from December 2007 to January 2009. This relates to the activity of the Popocatepetl Volcano and a radon survey and gamma-ray spectrometry in the area between Paso de...

Modulation of magnetic components of ULF Alfve´n wave (f=0.02–2 Hz), which is incident from the magnetosphere to the Earth’s surface, is considered. This modulation is due to variations of electron and ion concentrations within the ionosphere F-layer caused by acoustic-gravity waves or...