Abstract
This is a further study of the use of natural infrasound in the atmosphere to monitor tidal circulation in the lower thermosphere. The height of this circulation is determined with the use of a reference atmospheric model, which is then used to calibrate infrasound/microseism ratios in terms of height. Also, we show from continuous observation over six years at 41°N, 74°W that the winter semidiurnal tide is present at least 62% of the time and the diurnal, at least 42% of the time.