High Trace Velocity (HTV) infrasonic signals Possible origin Swedish-Finnish Infrasound Network Locally Observed Meteor Events HTV signal signature HTV signal scalogram Atmospheric vortices Stenflo, L.: Acoustic solitary vortices. Phys. Fluids, 30 (10), 3297, 1987. Satellite weather images Occurrence of HTV signals in Kiruna and Sodankyl a sample from Kiruna a sample from Sodankyl Sodankyl-motion pictures Intensity pattern on the ground Intensity ellipse Shape of the intensity ellipse for both samples 230x690 m 190x380 m Some properties Carry a lot of acoustic energy (up to 40 W/m2*sec) Are visible on the meteorological radar Kiruna infrasound and ESRANGE radar ESRANGE radar Similar phenomena? Certain forms of atmospheric turbulence Cold air vortex Some boundary layer phenomena? Martian dust-devils Cold air vortex Martian dust-devil