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

Abstract

During a solar eclipse the Moon's shadow moves at supersonic speed through the Earth's atmosphere. Chimonas and Hines^1,2 suggested 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 disturbance^5,6. 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.