The Earth is not round, it is wider at the equator, the atmosphere is moving, the atmosphere has different thicknesses at High and low pressures and at the poles compared to the equator, waves travel different speeds in different thicknesses and densities. The wave travelling West to East compared to East to West has a slightly different shape. There is some variability to offset an exact meeting on the opposite side. I wish the one minute data was available longer but I captured many reference locations. Oh also I roughly calculated the 2 waves in each direction and found one direction 23hr 10min for a full lap and the other 23hr 08 min. But I had to use the opposite wave speed from the eruption to the nearest station with opposite waves in each direction to get the total. But the waves were travelling the same speed past those stations that I used which were in Kenya and Trinidad and I used adjacent stations to calculate the speed and direction of the two waves.
well not exactly in a singular point, but kind of. Still interesting, I think.
I hope weatherflow makes a snapshot of this high res data and keeps it for research purposes.
I see two waves here near Seattle. Times are in PST.
The offset is due to altitude compensation in one reading due to how that station works. The math checks out.
Pressure trace spike around 9:30am EDT from my Tempest weather station from Tonga volcano eruption.
And another wave arrived back at Newcastle Australia after doing a full lap. Using the 5min resolution then zooming into the one minute resolution allows accurate time of arrival and shape. Doing the same on other Tempest stations in each direction allows me to determine its speed and direction as it passes over. We loose the one minute data after 24hours.
Cheers Ian
Air pressure perturbation measured ar Sumne Christchurch. This was followed by a series of lesser disturbances at intervals.
All rather interesting.
In the last day another smaller perturbation, but the cause is unknown.
Might it be the wave after it did a lap of the Earth? This is what I suspect was the wave returning after a full lap and moving past Invercargill 2 days later:
The initial I believe that is the reverberation as the wave as a reflection due to the shorter timing.
So on 15/01/22
1940 1020.9HPa - Ambient
1955 1023.5 HPa - Peak
2012 1018.9 HPa - Trough
2100 1021.7 HPa - Time to arrive back at a steady average
Reverberations about 3 hours apart
then on 17/02/22
0230 1015.1 HPa
0240 1014.5 HPa
0255 1015.2 HPa
This later one has no explanation. Enough of an aberration to be noted. It does not appear to relate to the Eruption but then it could be as the shock waves remain standing but diminishing for some time. Just an interesting point. Has anyone else seen something similar?
If you use the tempest map you can find everyones Tempests all over the World. The wave had a different pattern when it went West compared to where it went East and had also chaged by the time it returned after its first lap. But now that 24 hours has passed we can only see the 5 minute readings.
I did screen captures of the wave from many stations as I chased it around the globe.
The returning wave would have components from different directions at different times which might be your later waves. If you look at a station from Tasmania, Auckland Wellington and Invercargill you may be able to work out each waves direction. But is not as easy now the one minute data has gone.
Cheers Ian:-)
Thanks Ian, you would have been busy chasing this. Following the Laws of Physics, the wave would die down, from memory by the inverse of the square of the area it covered. We would see this reduction until it becomes unperceptable. I believe Karakatoa wave circumnavigated three times. But I guess in those days instrumentation was less sensitive than today.
but does it? in pure 2D you might be right, but the wave could concentrate again on the point on the globe right on the opposite site of the eruption (south of Algeria)
Sunny,
There will be an increase in pressure at the antipode point. However, that will be much less perturbation than nearer the site of the Eruption. Recall that energy has dissipated along the way. Hence the much smaller change at this “meeting point”.
of course it will be a lot lower than at the point of eruption. There is a lot of damping going on and there isn’t even an exact point, because the atmosphere isn’t homogeneous, wind changes the wave, but also the earth isn’t a perfect sphere.
I just wanted to make that comment because it isn’t going down purely with the square of the distance.
Sunny, the starting point in any consideration are the Laws of Physics. There after is the real world. So I fully agree with you. One thing that may also influence the reverberations are the atmospheric thermal layers. While these are less discussed, they exists, just as the thermal layers in the ocean. In the ocean these are used for submarine transmissions, to hide beneath, for whale conversations. I’m not sure how much use is, or can be made of the atmospheric layers. But it would interesting to know what impact this may have.
Your input is appreciated and stimulating. Thank you.
luckily I studied physics but I didn’t try to write out the formula of the height of the peak of a pulse wave traveling over a perfect globe (even when ignoring damping). There are too many factor to keep in mind, like dispersion
