Evidence of atmospheric gravity waves produced during the 11 June 1983 total solar eclipse

During a solar eclipse the Moon's shadow moves at supersonic speed through the Earth's atmosphere. Chimonas and Hines1,2suggested that the resultant cooling of the atmosphere would generate a bow wave of atmospheric gravity waves, which may be detectable as a travelling ionospheric disturbance or as a ground-level atmospheric pressure variation. Although the evidence for gravity waves in the ionosphere from a solar eclipse is still weak, they may have been detected3. Ground-level pressure changes during solar eclipses occur near the region of totality4, but the measured wave velocity and period do not agree with that of the predicted disturbance5,6. We now report the detection of a ground-level pressure wave detected at three stations in India and one station in Java, Indonesia. These data may provide the first direct observation of eclipse generated gravity waves over a very long range. The most distant station in India was 6,600 km from the eclipse centre line. The microbarometer recordings indicate that a wave disturbance was recorded at each station with a quasi-period of ∼4 h and a wave velocity of ∼320 m s−1.