I assume you mean by 'Same anomaly' the second shockwave (as the first is obviously directly from the volcano).RayProudfoot wrote: ↑Sun 16 Jan 2022 9:36 am Same anomaly here at the same time. What caused that? Secondary shockwave but unlike the first one pressure dropped before rising.
My interpretation would be as follows:
Hope this helps.As Tonga for us would be really almost at the opposite side of the earth (our antipodes?), the shockwave from its starting point would travel around the world and meet each other in the real antipode of the volcano. There it would start to interfere with each other and echo back (possibly reversing the amplitude depending on the interference point) the so called interference waves. (to simulate this, fill the bath at home and start dipping your index fingers 1 meter apart (once, at the same time). Observe what happens if the waves touch. Waves in air behave similar to waves in water. While interfering and travelling the wave looses energy so the amplitude is much lower.