Past IEM Features tagged: volcano
Tonga wave passage #4
19 Jan 2022 05:25 AMContinuing the series of feature posts showing the passages of waves associated with the Hunga Tonga volcanic eruption. This lapse shows the second passage of the westbound wave. There are many interesting aspects shown by this plot including smaller waves out ahead of the largest amplitude wave and again, the westbound wave looks subjectively stronger than the eastbound wave did. I think we'll stop with the IEM Daily Features showing these wave passages and relegate the subsequent posts to my @akrherz Twitter page as we'll perhaps catch a third passage of each! Focus needs to turn back to the dangerous cold wind chills and return to the deep freeze with temperatures over Iowa!
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Tags: tonga volcano pressure
Tonga wave passage #3
18 Jan 2022 08:38 PMYou'll have to pardon the continued featuring of wave passages from the Hunga Tonga eruption. This featured lapse shows the second passage of the eastbound wave that happened Sunday evening. While the wave is plainly visible, it is not as strong as the first passage. There are interesting quirks with how qualitatively strong the wave appears over various parts of the country. The reason for these differences is not readily known by the author at this time! We'll have at least one more lapse to share as the second passage of the westbound wave happened Monday afternoon. It is a testament to the power of a volcanic eruption that these waves are able to make multiple trips around the globe!
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Tags: tonga volcano pressure
Tonga wave passage #2
17 Jan 2022 07:56 PMYesterday's daily feature presented a sparkline map showing the passage of waves from the Hunga Tonga volcano eruption. Today's map presents the second wave passage event over the contiguous US, this one traversed the globe in the other direction and so arriving on the east coast first. This lapse is from early Sunday morning and guess what, there are still more lapses to be shown as the waves continue to propagate around the globe. It is unclear when these waves will disappear, but given the size of the eruption and some limited literature on previous documented events, it is likely soon. So these waves are not really impacting sensible weather any, but are certainly extremely interesting! Qualitatively, it seems like this wave strength was stronger, but the reasons are not clear and maybe an artifact of time of day and/or how this particular metric is being presented here.
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Tags: tonga volcano pressure
Hunga Tonga Eruption Sonic Wave
16 Jan 2022 08:47 PMLate Friday evening (Iowa time), a massive volcanic eruption happened near Tongo, a place north and east of New Zealand. The eruption generated a shock wave / sonic waves in the air that have continued to transverse the globe up until at least the time of this writing. Like waves you see in water, these waves create vertical displacements of air causing surface air pressure fluctuations. The featured movie presents an animation of minute interval pressure data observed from NWS/FAA ASOS stations. The data is presented in the form of "sparklines". Each line represents the map location of an observation time series lasting 15 minutes. The north/south variation in the line represents a change in pressure with the color being the magnitude over the 15 minutes. As you play the movie, you can at least readily notice the propagation of the wave across the country. Others on the Internet have computed this wave to be traveling at approximately the speed of sound! There are many other nuances that can be seen in the plot, including many smaller waves coming after the first wave. So, do you know what is even crazier? There was another wave transversal earlier this Sunday morning from east to west as the initial wave from Tonga made its way east around the globe and arrived at the USA. The one minute data is not available from it yet, so check back later for another lapse from it.
Voting:
Good: 24
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Tags: tonga volcano pressure