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During last decade, due to fast progress of thermal infrared (TIR) technology, all weather, high-resolution and highdynamic
range of new developed sensors, a large time-series data base is available for seismic anomalies monitoring. As
received satellite infrared information is influenced by many types of factors, the main problem for seismic anomalies
recognition is to extract useful information associated with tectonic activities and to eliminate the effects of non-tectonic
factors. Pre-earthquake spatio-temporal thermal anomalies are controlled by various factors like as earthquake moment
magnitude and its focal depth, geological setting, topography and land covers. In this paper, changes before and after the
Vrancea earthquakes in the atmospheric parameters have been investigated on the basis of time-series geospatial and
field data analysis. The detected changes show a complementary behavior in terms of the various atmospheric
parameters, further showing strong evidence of coupling between lithosphere-land surface-atmosphere associated with
the Vrancea’s earthquakes. Have been selected the atmospheric earthquake presignals detectable from space: surface
latent heat flux (SLHF), and air (AT) surface temperature anomalies, provided by time-series satellite NOAA AVHRR
and in-situ monitoring data. For some analyzed earthquakes, starting with ten days up to one week prior to a moderate or
strong earthquake a transient thermal infrared rise appeared in SLHF (tens of W/m2) and AT (2-10°) values higher than
the normal, function of the magnitude and focal depth, which disappeared after the main shock. The joint analysis of
geospatial, geophysical, and geological information is revealing new insights for Vrancea zone seismicity understanding
in Romania.
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