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How big was the Tonga eruption?

graphics.reuters.com

191–200 of 269 posts

Re: How big was the Tonga eruption?

#191

I posted a visualization of the shock wave as a submission, but I"ll repost it here. This is a satellite measurement of integrated atmospheric water vapor (IIUC), so changes in the density of air change the integrated measurement, such that you can see the shock wave travel around half the globe. https://cimss.ssec.wisc.edu/satellite-blog/images/2022/01/22... (it take a few seconds to load, but I believe this is one…

Incredible! Thanks for posting this.

Re: How big was the Tonga eruption?

#192

Wondering if any ships were destroyed by the eruption the scale makes me think there had to be? Could Volcano eruptions be Earth's way of stabilizing climate change? i.e. sea water gets warmer and is no longer keeping the eruptions from occurring. Then the eruptions causes a drop in temperature due to the ash in the atmosphere?

> Then the eruptions causes a drop in temperature due to the ash in the atmosphere? Interesting, this prompted me to read[1] into how it works and made me interested in why we don't pump sulfur dioxide into the atmosphere to help cool down the planet and buy us more time to transition off of CO2/CH4 emitting processes? Is it cost prohibitive? We already cloud seed pretty often so there's infrastructure in place for a…

"But there are at least 27 reasons why stratospheric geoengineering may be a bad idea. These include disruption of the Asian and African summer monsoons, reducing precipitation to the food supply for billions of people; ozone depletion; no more blue skies; reduction of solar power; and rapid global warming if it stops, with devastating impacts on natural ecosystems. "

https://cires.colorado.edu/events/stratospheric-sulfur-geoen...

Re: How big was the Tonga eruption?

#194

Earlier quoted context omitted.

But there would be a spot where the pressure waves would cross?

I think so. I think there is necessarily a circle "eversion" (turning it inside-out) with a crease. Whatever is the point of the crease would hear sound from all directions. Even with something like a figure 8 collapsing wavefront, eventually one or more creases should form.

If the crease is a line, would it not sound like comming from two opposite directions simultaneously?

Re: How big was the Tonga eruption?

#195

Curious if this will cause a slight cooling of the earth's air temperature due to increased volcanic particles in the air. I had no idea of the size of this eruption and it looks absolutely enormous based on this article. It didn't mention how many metric tons were ejected into the atmosphere Here is an article saying that after a eruption the air temperature rapidly cools for a while. Lets hope this doesn't wreck cr…

Not this time apparently.

> Pinatubo erupted for several days, sending about 20 million tons of sulfur dioxide gas into the stratosphere, or upper atmosphere. There, the gas combined with water to create aerosol particles that reflected and scattered some of the sun’s rays, keeping them from hitting the surface. That had the effect of cooling the atmosphere by about 1 degree Fahrenheit (about half a degree Celsius) for several years. (It is also the mechanism of a controversial form of geoengineering: using planes or other means to continuously inject sulfur dioxide into the stratosphere to intentionally cool the planet.)

> But the Hunga eruption lasted only about 10 minutes, and satellite sensors in the days that followed measured about 400,000 tons of sulfur dioxide reaching the stratosphere. “The amount of SO2 released is much, much smaller than, say, Mount Pinatubo,” said Michael Manga, an earth sciences professor at the University of California, Berkeley. So unless the Hunga eruption resumes and continues at a similarly strong level, which is considered unlikely, it won’t have a global cooling effect.

- https://www.nytimes.com/2022/01/19/climate/scientists-tonga-...

Re: How big was the Tonga eruption?

#196

Earlier quoted context omitted.

US tsunami monitoring has a record. https://www.tsunami.gov/previous.events/?p=03-19-09-Tonga

A tsunami is a wave. Not sea level. Waves literally come and go over a period of seconds to minutes. They wobble back and forth without actually moving much water. Sea levels move on the order of hours and days and involve the physical movement of literally hundreds of cubic-miles of water. Raising or lowering a sea level measurement (not a temporary wave) requires far more energy than a volcano. From the link: "List…

A tsunami is an entirely different kind of wave than a normal wave.

A normal wave is transverse, and a tsunami is a pressure wave. The first bobs the water up and down and the wave moves forward, the second shoves water ahead of it, displacing it upward into the wave.

The tsunami won't break when the column gets short, but rather transfer all of the energy of moving a deep water column to a shallow one. That's what makes them dangerous.

Re: How big was the Tonga eruption?

#197
post #188

Earlier quoted context omitted.

I'll celebrate for a whole week whenever the US converts to the metric system. I hope I'll still be young enough to handle it.

Since it's a big "moat" for parts manufacturing (mainly for defense industry)... I predict the USA will give up imperial units when it's empire finally collapses. Perhaps in the next few decades as China builds its own economic sphere.

Um, it's unamerican to use "imperial" units. When you have a revolution, you have to get rid of all things imperial!

Therefore US pints are 16oz, not 20oz, and so on for most fluid measures (fluid ounces are based on dry ounces, which are avoirdupois, not imperial).

Re: How big was the Tonga eruption?

#198

I posted a visualization of the shock wave as a submission, but I"ll repost it here. This is a satellite measurement of integrated atmospheric water vapor (IIUC), so changes in the density of air change the integrated measurement, such that you can see the shock wave travel around half the globe. https://cimss.ssec.wisc.edu/satellite-blog/images/2022/01/22... (it take a few seconds to load, but I believe this is one…

139MB is utter insanity for an animated GIF. Crushing it with gifsicle can get it down to 125MB but clearly GIF is the wrong choice of format here. Here's a HEVC compressed video version which is only 25M and suffers only extremely mild softness: http://david.gloveraoki.net/f/32M.mp4 It would probably be even better if I could work with the source video and not the gif version.

idk, I had no issues loading the gif and playing it. For some reason your video doesn't want to play in Chrome. I had to download it first.

Re: How big was the Tonga eruption?

#199
post #127

Earlier quoted context omitted.

Even exactly on the other side of the world, the sound will reach you at different times from different directions due to different pressures, temperatures, mountains, etc. on the way.

But there would be a spot where the pressure waves would cross?

I think it’s highly unlikely that even half the pressure waves would simultaneously reach a single point on earth. The waves get reflected in all kinds of ways by the ground, mountain ranges, difference in air temperature, etc.

If they did, however, I wonder how strong the force would be at its focus (if that’s the proper name)

(If I did my math right, the antipodes of Tonga live in the south of Algeria, near the Niger/Mali/Algeria tripoint. I haven’t heard of weird phenomena happening there, but then, I don’t think that is the most populated and most twitter-addicted part of the world)

Re: How big was the Tonga eruption?

#200
post #188

Earlier quoted context omitted.

Since it's a big "moat" for parts manufacturing (mainly for defense industry)... I predict the USA will give up imperial units when it's empire finally collapses. Perhaps in the next few decades as China builds its own economic sphere.

Um, it's unamerican to use "imperial" units. When you have a revolution, you have to get rid of all things imperial! Therefore US pints are 16oz, not 20oz, and so on for most fluid measures (fluid ounces are based on dry ounces, which are avoirdupois, not imperial).

We kept linear measurements the same (feet, yard, miles). So it's a bit of a stretch to say we're not imperial. I'd say it's "US imperial".
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