Geophysical Effects of Strong Fires in a Megalopolis Conditions: Observation Results

We present the results of synchronous observations of microbaric oscillations and variations of electric and magnetic fields during large fires of man-made origin in Moscow. The main instrumental observations were carried out at the Center for Geophysical Monitoring in Moscow at the Sadovsky Institute of Geosphere Dynamics of Russian Academy of Sciences (CGM IDG RAS). Using an analysis of the data, we show that large fires in a megalopolis are manifested in microbaric variations and variations of the electric and geomagnetic fields in the surface atmosphere. Under certain conditions (the absence of intense natural movements of air masses and sufficiently strong heating of the atmosphere in the combustion source), fires can lead to an increase in wind speed and direction in an area up to 25 km. The emergence of a dynamic region with altered thermodynamic characteristics above the fire zone causes the formation of infrasonic waves during the period of the most intense combustion. Strong fires lead to an increase in the concentration of fine particles in the surface atmosphere.