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.
I love how the helpful engineers of hacker News come to the aid of the poor soul who's inadvertently uploaded their video of the biggest eruption in the last 30 years in the wrong format or without the proper compression. I love that...it's like, 'happy to help to make everything more efficient!'
In other news IT still takes days to get back to me about getting my BYO device onboarded...
I'm not saying it's a paradox just noticing the juxtaposition
Your video doesn't work either but the GIF worked fine. I get MIME type not found for yours.
Also the video is full of very fine scale noise. Something that won't compress by HEVC very well at all. You want a lossless compression method (or a very high perceptive index on HEVC).
Is interesting Gif size. With ShareX I get massive Gifs, but Kap on Mac I can get much smaller files (this is 14fps). Same for screentogif massive files... not sure what makes them so big.
I was wondering the same thing. One factor might be the variation in propagation speed, which is visible for example due to winds near low pressure systems.
What’s happening immediately east of the eruption? There is a point water vapor variability in the center of the shock wave start and another single point of water vapor variability of equal size without a shockwave.
Heard it go bang, 2600km away, echoing through the hills around our place at the top of the South Island of New Zealand. That's pretty staggering to think about it. Then to see other peoples Home Assistants around the world pick up the change in pressure on opposite sides of the planet. Mental, just mental...
I live on the beach on the East coast of Australia. We had a marine tsunami warning. We were a few floors up so I wasn't really worried about myself.
About 12ish hours after the initial eruption I thought that anything that was going to happened had all passed by hours ago and I was talking with friends online.
Randomly I started hearing this white noise kind of sound (it sounded like the bubbling water of a kettle without any whistling). I took my headphones off and opened my door trying to find the source of the noise, thinking that the kettle had turned on.
I looked outside and what was small surf conditions only 3 minutes before was extremely turbulent with white frothy waves moving in every direction. It looked like it was reacting to an earthquake but there was no movement in the ground. (I've felt an earthquake there before which is rare here but since our foundations are in the sands I've had the experience and could tell there was no earthquake in the ground on the morning after the eruption)
Since the waves were moving in every direction, some of them were colliding head on. When this happened and the peaks and troughs were interacting in the right way they were shooting out jets of water spray at my eye level about 15m above sea level (I could tell since they were intersecting the horizon from my perspective).
It continued for about a 30 seconds, calming down over another 30 seconds. After the surf had lowered itself to its previous levels, the whole top of the water going back about 50ish meters was covered in thick brown foam. All of the turbulent waves had dredged up the sand beneath it.
The foam slowly disappeared over about an hour with the last bits being the foam that ended up getting washed ashore and out of the water's reach.
I've heard that the Krakatoa eruption was so loud that the sound wave reverberated around the globe several times. I assume that means if you're on exactly the other end of the world, the sound is coming at you from every direction? Similarly, no matter where you are on earth, the sound is coming at you from different directions at different times? Of course, I'm assuming that the sound wave was in audible frequencies which may or may not be the case...
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.
The earth is (almost) an oblate ellipsoid so most geodesics on earth aren't closed and even if they all meet (do they? I need to to think about this or play with GeographicLib) at one point they are of different lengths (imagine a point on the equator, the latitudinal path is quite different from the longitudinal path). And then there are different propagation velocities due to pressure, terrain, etc. So probably not.
> But there would be a spot where the pressure waves would cross [simultaneously]?
There could be, but it's not immediately obvious that there has to be.
It does seem like certain points would need to be on 'cusps' of the wavefront, though, so something like getting the wave from the north and the northeast 'simultaneously'.
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)
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.
Teeny little dip and crest, and I wasn’t sure until the meteorological station in a city 30km tweeted that they’d seen it too, and the times coincided (well, I was about a minute later) very neatly.
It's always interesting that anyone who lives in a "Bay", refers to their local as THE Bay. For this phenomenon, which is documented as circling the globe, who knows where this could be!
The "Bay Area" is well known to refer (only) to the San Francisco Bay, while the "Greater Bay Area" is known to only refer to the Pearl River Delta Bay (HK, Macau, Guangdong). Other bays are typically named more specifically (e.g. Tokyo Bay, Monterey Bay, etc.).
You'd be more on point if OP had referred to San Francisco as "The City" as many in the City do; since that's something that's also used in other cities like NYC.
NB: current resident of the Greater Bay Area in China and former resident of the lesser Bay Area in California.
I was outside in my backyard when I heard a mild crashing sound around 7 or 8am in Toronto. I thought the neighbour had dropped a ladder or metal garbage can or something…but after reading the news I realized it could have been the Tonga explosion.
I noticed the same on all in Aqara Zigbee temperature/pressure/humidity sensors. They're all inside, I could still easily see it twice (many hours apart). Though I only noticed after someone in a Home Automation topic mentioned seeing the effect ;)
What did the “bang” sound like? Was it the sharp crack of thunder close by, the slower rumbling of distant thunder, the sound of fireworks exploding, or would some other description fit better?
I also heard it in the north of the South Island of NZ. To me it sounded like very distant explosions, like a cannon firing, or avalanche control explosives.
We heard multiple explosions over the span of a minute or two, presumably from the multiple paths the sound took as they all sounded the same.
Close up (next island over) it was a low loud fast boom like dynamite going off nearby. Over in an instant. From a Facebook video. Really strange that it would sound that way.
I find it difficult to believe that even a massive eruption could literally push sea levels up or down in the surrounding area (waves /= sea level). Volcanoes are massive, but the energy to move cubic miles of water, water many hundreds or thousands of miles away, is at different level. Hurricanes can move water like that, but they do so with orders of magnitude greater energy (tens of thousands of nukes).
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: "Listed wave heights are maximum amplitude in cm (above sea level)." In other words, even tsunami waves heights are not changes to sea level.
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.
They were initially responding to a comment that said sea levels were slightly elevated for a week after the eruption. I have to agree that's pretty weird even for a tsunami.
> 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.
You should be aware that tsunamis behave in the way you're calling "sea level", and not in the way you're calling "wave". It's true that a tsunami is a wave, but it's not true that they come and go over a period of minutes, or that they fail to move much water. They're very large.
Some of them, specifically those involving undersea plates moving upwards, but even those do settle out quickly. That is why the term literally means "port waves" because they bypass normal wave protections and move into ports, similar to how tidal bores move up rivers. But the comment above spoke of sea levels being impacted for many days, something beyond even thrust tunamis and more akin to hurricanes.
Think of it more like a very long period wave, much like a tide, but on a much shorter time period than the tide. Tides, waves (periods on the order of seconds), and tidal waves (or tsunamis) are all fluctuations in sea level. Water can be moved when the waves encounter enclosed bays or harbors. Think of the water level dropping 3 ft over 20 minutes in front of a harbor entrance and imagine the currents that can result.
If it has a period not tied to the rotation of the earth (ie tides) then it is not a change in sea level but a wave. And Tsunami does not translate as "tidal" wave. It means "port wave" and has nothing to do with tides whatsoever.
We also heard it while tramping on the thousand acre plateau just north of Murchison. It was very quiet, so we were lucky to be where we were with no noise pollution to drown it out.
Though at the time we had no clue what it was, we joked about being in the Tomorrow series timeline.
The Pacific Ocean is ginormous (I think that’s the technical term?) I often find myself surprised when I spin a globe (physical or virtual) and compare the expanse of the ocean to my neighborhood of the planet. The scale also makes the history of Polynesian seafaring all that more incredible.
I recently read a book about South America and learned there’s genetic evidence Polynesians made there in about AD 1200, which is amazing.
There’s also I think some mystery about some South American DNA that doesn’t support the land bridge hypothesis. I don’t know if that’s well supported or not/evidence might be poor, haven’t bothered to do any digging. I think that’s distinct from what was found linking some populations to Polynesians and suggests there might have been seafaring people that made it even earlier, but I’m not sure.
Yes, they had incredible techniques. They could detect a remote island by the way the swell is disrupted. Also recently read about Magellan's voyage and it is remarkable that they made it.
They set themselves a task that they weren't up to, and they failed at it. It doesn't make sense to say "it is remarkable that they made it", because they didn't make it.
You know this happened 500 years ago, right? If someone did this today and had that death rate, I would absolutely agree, but the challenges then were drastically different. No, not everyone made it, but those who did were the first to circumnavigate the planet - and they very much did make it.
A little off topic, but as a reminder of how different the world used to be: families used to move across the US on foot, maybe with a wagon carrying their supplies, and many died doing so. I'm quite thankful I can just get on a plane to see my family :).
Also, as someone who needs to remind themselves occasionally to be less negative, I would encourage you to be less negative about things that aren't 100% a success.
P.S. If you really want to hate on Magellan it would make sense to do so for something like him burning a village in Mactan because they didn't want to convert to Catholicism[0], not this. You may be pleased to hear that this directly led to his death.
By any metric related to exploration they were wildly successful. The amount of information that was gathered and relayed on a single voyage at that point in history was astounding, and the story was incredible.
Our previous Commanding General once quipped that PowerPoint presentations that transition between geographic focus areas should include slide after slide after slide of blue ocean, to communicate the vast distances involved in our Area of Operations. Otherwise no one appreciates the distances between the islands that are of interest. Too many people think Hawaii and Guam and the Philippines and Okinawa are all just down the street from each other.
I mean your not wrong, the article is illustrating the mushroom cloud and ash cloud after 24 hours. So the explosive eruption its self is much smaller.
"Around the time of the initial eruption, a cloud measuring 38 km (24 miles) wide is thrust into the atmosphere. Its diameter already measures almost twice the length of Manhattan, New York. One hour later, it appears to measure around 650 km wide, including shock waves around its edge."
One hour.
Sanity check: it's never dark in the animations, which it would be if the images were taken over 24 hours. In other views you can see the night approaching.
No, there is no missed rule, the comma is the only official decimal separator in these parts.
But I can relate to the the OP.
Us here in the comma world are forever converting numbers in CSV and Excel files back and forth so as to display them in a proper number format.
It’s like that darned USB port, you have to flip it 3 times to get it right.
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.
I was about to comment that feet, yards and miles are not imperial measure; but I checked, and WP says they are in fact imperial units. So i learned something today.
We also use apostrophe as the thousands separator, so: 1'234'567.89 which I personally always found much more readable that using commas and dots. Is there any other country that uses this combination?
While OP here made a mistake, some countries use mixed systems depending on what it is used for . Switzerland for example uses comma for normal numbers and dot for currency alone.
Did the the ocean influence the ease of expansion of the explosion? Or hinder it? We are comparing an underwater explosion to one on land, and I'm wondering if it's directly comparable.
From what I've read it seems that the ocean exacerbated the explosion: the hot magma caused water to vaporize and created a steam explosion. I've read about a 70x volume expansion and that the top altitude of the plume was steam.
On the other hand, the ocean might have captured some of the ash (?)
This reminds me of Jules Verne’s Mysterious Island, which was the first adult book I ever read. It featured a catastrophic underwater volcanic explosion. Great book, it’s a Robinson Crusoe-style sequel to Twenty Thousand Leagues Under the Sea.
Interestingly, Verne wrote the book nine years before the Krakatoa explosion. He must have been thinking of Tambora, though I’m not sure that eruption was well recognized at the time.
I ran a quick bit of napkin maths a few days back here on HN.
Based on 6 MT energy release, a maximum of 11 million tonnes (or 11 million m^3) of water could have been vapourised.
Liquid-to-gas expansion is on the order of 1,000 times, not 70x. This would be 11 km^3 of expansion.
If the erruption yield was higher, and I've seen values of up to 50 MT suggested, the amounts would be roughly 9x greater: 100 million tonnes and 100 km^3 of steam.
All of this is very rough and is strictly based on the quantity of energy and the heat of vapourisation of water. Actual quantity of water/steam is likely lower. There's no geology involved in the estimate, just physics.
I'm curious if this would cause a noticeable change in the pH of those waters, and if that could be a good basis for estimating how much ash was captured.
It should have also significantly reduced the temperature of the resulting ash cloud which reduced the quantity of particulate matter in the upper atmosphere. Which presumably reduces how much short term global cooling you get from the eruption.
For western US trained geoscientists, the Bishop Tuff [1] (from the ~750,000 years ago eruption of the Long Valley Caldera, near Mammoth Mtn. in California) is a "modern" comparable ashfall deposit.
This was quite a bit larger (edited to add: I meant in areal extent, not necc. volume erupted).
I was vacationing in Mammoth one time and started reading about the geology... quite a shock to find that basically everything to the east is a giant caldera [1]. Also 760,000 years ago is really quite recent on geologic time scales.
That's about the same size as the Henry's Fork Caldera [0] which is within the much larger Island Park Caldera [1], both produced by the Yellowstone hot spot. The Island Park Caldera is one of the largest in the world.
I don’t understand. Literally all of Hawaii is built on top of lava flows. Are Hawaiians dumb idiots for building roads and other infrastructure on top of lava flows?
True, but we were dumb enough to build a civilization on this planet and lava will flow everywhere the next time we have something like what caused the K-T event so I suppose it runs in the family.
Its eruption history is on the order of once every hundreds of years. By the time its next eruption comes around, it's very possible that infrastructure will be long gone for other reasons.
In most cases, infrastructure existence and placement is barely a blip on geologic time.
you could make your point without being derisive and ableist, especially considering the people involved have credentials and are trained in their fields.
I had to read it several times to get it, but I think they’re referring to “dumb” which could also refer to people who can’t speak.
The funny thing about this is that I simply read “dumb” as “stupid” and didn’t make any connection to being mute - but thanks to the earlier comment I’ve now made the association. So, well done policing the discourse, I guess?
To answer your question, adjectives related to intelligence are ableist in origin. I don't think this needs to be explained and it's not my job to educate you or anyone else on this forum.
There should be a word for the driveby condemnation (ooh we could call it that) that is "what you said is unethical but it's not my job to tell you how".
I doubt driveby condemnation will convince many people.
I mean, that's a fair point. I just feel this sort of dialogue is disrespectful to the engineers who actually build the stuff the grandparent commenter is complaining about.
moot since the comment itself is dead/flagged but if you're calling people idiots, show me your credentials.
Yeah, I agree with you on that, I've just heard the "it's not my job to educate you" point (you're right, it's not) before, and I've noticed it only tends to make the conversation worse.
I think that's because without the explanation it's more or less name-calling, since the accused doesn't know what they did wrong.
But it creates "engagement" which is rewarded these days apparently.
Also, I thought the trained people should have learned a thing or two from Pompei not to build near volcanoes. I'll cut some slack for the people who designed Pompei, they didn't know, but everyone after that should have learned.
What are the chances that the volcano erupts with a train on/near that portion of track? How often would you likely have to fix it? How much does it cost to go around? I am sure these questions are being asked and the risks being weighed. They may not be right and you might not agree with them but unless they did this without any forethought I would not call them dumb. Also you are comparing them to Pompei even though this is a train track not a city.
It would disrupt critical supply chains. That train line is part of a key freight artery between Seattle, Portland, SF, LA, and SD.
Railroads and highways also invite towns and cities to be built around them, so if you want to be responsible toward future generations of human lives, you should direct those major arteries through less geologically-active regions.
Hugging an active volcano never was a good idea in history and it still isn't.
OK, I meant more like "dangerous hot shit that wipes out everything in its path" in a general sense.
If someone gave me a contract to build something in modern-day Herculaneum I would say no. I think it's irresponsible to build there. In terms of lives lost it's tantamount to knowingly shipping a hundred 777s with loose screws that cause them to crash.
The number of downvotes on this thread is also exactly why we have disasters with volcanic eruptions. This is like the geological equivalent of a bunch of antivaxxers.
This reasoning cannot lead to a practical policy directive. Volcanoes often lay dormant for thousands of years and their eruptions can deny huge amounts of land, which is not a reasonable tradeoff compared to "just rebuilding the railroad every 5000 years", since its service life is probably shorter than that anyway.
> I mean, how fucking dumb do you need to be to look at a lava flow and cut a road or train track through it? Do they not realize that lava means "run"? Build infrastructure elsewhere.
Right, and nobody should build cities on rivers or coasts, because rivers flood[1] and coasts get hurricanes that cause floods, nobody should build anything in valleys[1], because they flood, nobody should ever build anything in mountains, because they get avalanches and mudslides[1], nobody should build anything on the Ring of Fire, because earthquakes, and the midwest should be uninhabited because tornadoes.
If someone built a two-lane road that cuts through an old lava flow, maybe those people aren't the idiots. Maybe they've done the math, and determined that the cost of going around it is going to be greater than the risk of eruption * cost of dealing with the consequences.
> Right, and nobody should build cities on rivers or coasts,
Many ancient civilizations knew not to build on coasts. Beijing, Xi'an, Cairo, Rome, Paris, Mexico City, Madrid, London, Moscow, Kyoto, most of these cities of critical governmental and strategic importance were not built on coasts for very good reasons.
And then you have some modern hipsters after the 17th century who decided not to take a history lesson and started to build NYC, Shanghai, LA, Tokyo, Shenzhen, Singapore, Washington DC, and other cities on the coasts. Note that none of these cities have much history to them, for a reason. Not a good plan. Humans are pretty dumb.
You've cherry-picked a bunch of non-coastal cities, but completely missed that nearly all of them were built on rivers.
Which have all of the same problems with flooding as coasts, but much worse. Coasts flood when you get a major storm causing a surge, or a major earthquake. Rivers flood when the seasons change, when it rains upstream, when you get a mudslide upstream, when there's a major earthquake sending a tsunami upriver...
Why do you think cities built on coasts and rivers on the whole grew, and out-competed cities that were built inland?
Ancient civilizations did build on coasts, you're cherry picking a handful of cities that weren't, but most (if not all, going off memory) of the cities you listed were built along rivers. Building on the coast gave (and gives) access to trade and fishing which are of great utility to most societies.
Besides, avoiding the coast itself doesn't do you much good. Earthquakes, volcanoes, flooding (from rivers or rain), drought, fire, tornadoes can hit in many different areas even away from the coast. Hell, hurricanes can go pretty far inland and do quite a bit of damage (more from the flooding than the winds, but also the winds, at that point). You'd be hard pressed to find a totally safe place on this planet that could support the entire human population. You'll still need the hazardous areas for agricultural and mining purposes if nothing else, and unless people can handle a 1000 mile commute, you'll end up with communities and cities growing in those places.
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?
I'm no expert but I can't think of many reasons for a boat to be there.
I remember reading about that Malaysian flight that got lost few years ago in the indian ocean and apparently this area is so uncommon that the closest ships are often more than 1 thousand kilometers away.
The only ships that could be there would be local, but there was an eruption and tsunami alert issued the day before, so I guess that would only leave ships doing work related to the volcano itself.
> 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 large scale operation?
"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. "
This looks like a tedious process that I would have totally done on my own had I thought of it. By that I mean the painstaking process of matting out each frame, then randomly placing it on places of the map, just because I could, just for the lulz. I'm not discounting it as "i could have thought of that", but appreciation for how useful it actually is.
Some people cannot grasp certain things without visuals, and this visual is one of those that definintely makes things clearer.
I like they handle the relational scaling for you as you zoom in/out. I was disappointed at not seeing an option for scaling, but nodded appreciation with "it just works" aspect
Sure, that's fun. That has been taken much further than I would have bothered by just placing a cutout on maps and saving those images. Somebody had an idea, and just didn't stop, and took it to that level. My modern day level of "cleverness" would have stopped well before thinking, "ooh, integrate into a live website". That is clever and allows others to share in the fun.
Yes, they did use transparent shadows. You can tell because the images are not GIF's, they're actually a sequence of PNG images overlayed atop other PNG images. There's the base satellite image of the area, then the frames-of-explosion-with-transparency overlayed atop them. You can confirm this by right clicking on the image and choosing "open image in new tab", which will (usually) open this final frame in a new tab.
I tried to save one of the "gifs" to share with a friend and was quite upset that I found myself with a png. Interesting technique. Do you think this was done to have better quality animated images? GIF compression isn't amazing (relative to WebM at least)
Very gratified they didn’t just post these as rendered gifs.
Imagine the social media scare you could generate in a year or so after everyone has forgotten about this eruption by sharing a graphics.reuters.com URL for one of these animations that appears to show a satellite image sequence of a massive mushroom cloud obliterating the Korean Peninsula or the Sinai with a breathless ‘LOOK WHAT REUTERS JUST REPORTED!!!’ caption.
It’s really important for reputable sources posting images to think about the fake news potential of them getting shared out of context.
Probably more along the line of they have some library that uses PNG sequences. Maybe even as simple as a slideshow with short durations. It's a newsy site. They don't have a lot of control over what their CMS/publishing platform can do. Someone probably had a clever idea on how to use something existing in a way not envisioned when created.
Yeah I agree! I knew the eruption was big (being able to clearly see it from space), but those visuals 1) make me remember how big the Pacific is, 2) how much bigger the eruption was than I originally thought, when overlaid on somewhere I know the relative size of (such as Florida).
I agree. Not exactly the same, but I live on the southern shoreline of Lake Michigan, and every year/summer, it claims the lives of many people (mainly swimmers). I've watched coast guard helicopters, drones, boats cover (what seems to be) every foot of the few square miles the person was last seen, and still be unsuccessful at finding the missing person. Unimaginable scale when compared to the Pacific!
The 6-10MT estimate is really a lower bound based on the amount of material moved from the island. A more reliable estimate is based on the overpressure, which was significantly larger than the Tsar Bomba (also exploded over an island) which was 50MT. https://text.npr.org/1074438703
That said, the amount of SO2 was fairly low, so the climate impact not likely to be large.
I heard from an Anton Petrov video it would reduce the planets average temperature by half a degree for some time, but I don't know where he got that info from.
It's possible that estimate was based on the eruption size, not the SO2 amount. It seems that the amount of SO2 emitted wasn't that much, so maybe something much less than 0.5 degF.
We have had really beautiful sunsets here in Northern California for the past week. Maybe related? (We also have a winter wildfire in Big Sur that could be contributing.)
Globally event appears unlikely to have a significant cooling effect on temperatures globally, h
>"However, to date, it injected 'only' 0.4 Tg (400,000 tonnes) of sulphur dioxide into the atmosphere, which is not enough to result in significant surface cooling for this individual eruption. "Unless further eruptive activity occurs, we should not detect significant surface cooling. At present, hazards related to ash fallout are really the number one concern."
This is amazing, and superimposing it over other land masses really helps to illustrate the point. I think it would be incredibly helpful to compare it to interstellar events from comets, especially to the (supposed) impact of the comet from Don't Look Up...
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 crop production.
> 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.
Too bad? It would be extremely cool for one summer, ruining crops and causing famines and then back to hotter summers from next year onwards. How does that help anyone?
You are describing an extreme cooling effect. If the Tonga eruption produced merely a mild cooling effect, it could contribute to the energy balance. Buying another year of frozen permafrost sounds ok to me.
Dr. Edna Casey: It means, Mrs. Carter, your husband, President Carter, has become [ camera zooms in on Dr. Edna Casey ] The amazing colossal president.
Rosalynn Carter: Well how big is he?
Dr. Edna Casey: Well Mrs. Carter, it’s difficult to comprehend just how big he is but to give you some idea, we’ve asked comedian Rodney Dangerfield to come along today to help explain it to you. Rodney?
[ Rodney Dangerfield enters ] Rodney Dangerfield: How do you do, how are you?
Ross Denton: Rodney, can you please tell us, how big is the president?
Rodney Dangerfield: Oh, he’s a big guy, I’ll tell you that, he’s a big guy. I tell you he’s so big, I saw him sitting in the George Washington bridge dangling his feet in the water! He’s a big guy!
Rosalynn Carter: Oh my God! Jimmy! Oh God!
Rodney Dangerfield: Oh, he’s big, I’ll tell you that, boy. He’s so big that when two girls make love to him at the same time, they never meet each other! He’s a big guy, I’ll tell you!
Rosalynn Carter: Oh no! Oh Jimmy! My Jimmy!
Rodney Dangerfield: I don’t want to upset you lady, he’s big, you know what I mean? Why he could have an affair with the Lincoln Tunnel! I mean, he’s really high! He’s big, I’ll tell you! He’s a big guy!
Rosalynn Carter: No! No! No!
Ross Denton: Rodney, thank you very much. You can go.
Rodney Dangerfield: It’s my pleasure. He’s way up there, lady! you know what I mean? [ goes off, leaving Rosalynn Carter very upset ]
I have been reading Termination shock by Neal Stephenson and this eruption reminded me of the main plot in tat book - injecting sulphur dioxide into the upper atmosphere to reduce heating. It will be interesting to track the effect of this eruption downwind.
Someone else estimated the Tonga explosion at 10 megatons [1] and it was heard thousands of miles away. Bear in mind, humans have detonated nuclear weapons larger than this, most famously the Tsar Bomba [2] at 50 megatons. Compare this to something not that long ago: Krakatoa, estimated at 200 megatons [3].
Then compare this to the Year Without Summer (536 AD) [4]:
> Falling in the time known as the 'Dark Ages', the year 536 AD fully embraced this moniker as Europe, the Middle East and parts of Asia were plunged into 24-hour darkness for 18 months. Summer temperatures plummeted between 1.5-2.5°C causing crops to fail and millions to starve to death.
All of this has happened in the last 10,000 years, which is regarded as a relatively stable period and a mere blink of the eye in cosmic timelines. I'm reminded of the thin blue line [5]. You begin to realize how narrow a niche we live in.
Humanity almost died out 70,000 years ago [6]. It's not really known why. There are lots of theories on the cause. It's estimated the population dropped into the tens of thousands. It's actually a big reason why there is little genetic diversity in humans (compared to other primates, for example).
Far worse has happened on Earth and will likely happen again: the Chicxulub impact, supervolcanic eruptions like Yellowstone (about every 700,000 years in recent times), the magnetic poles flipping (and what that'll do to solar radiation hitting the Earth) and so on.
And all of these pale into comparison to any space-based cataclysmic events (eg gamma-ray bursts, supernovae, magnatars, neutron star and black hole mergers).
It really makes you think how fragile our existence is.
That is huge! As someone who originally came from tropical country, volcano eruption sucks even if you live far away from it. The dust, the earthquake, tsunami warnings, etc. hopefully everyone who is affected is doing fine
I would like to see, "MEDIA COVERAGE OF Tonga eruption compared as if it had happened in various Nations". Because apparently no one knows anybody who lives in Tonga with a camera, but damn that high tide at the Berkeley marina was crazy!!
The submarine cable connecting Tonga to the world was severed. While satellite connections exist, apparently the ash cloud interfered with that as well. It has been extremely difficult/expensive to get any pictures out of Tonga.
I have a great aunt who lives in Tonga - my Grandma spoke to her a couple days ago. Apparently people on the main Island (Tongatapu) are mainly fine - her main issue is a bunch of ash on her roof, which apparently is going to cost for $500 to get removed from local tradespeople.
Yes, these images are incidentally an excellent reminder to Europeans of how big the United States is. I read a lot of criticisms of the US from people overseas that seem to rest on a lack of understanding of the scale of the country. The US is huge. A volcanic plume that covers most of Britain or Spain would only cover about half of California.
You can wrap your head around it using "Measure distance" in Google Maps and comparing some in the US to Europe. Some examples:
- ~1,200 km will take you from London to Valencia. You can fit a straight line that long just in California or Texas.
- Miami to Seattle is about as long as Gibralter to Moscow. Tronheim in the Arctic Circle is closer to Cairo than Seattle is to Miami.
- Paris is closer to Tehran than San Diego is to Bangor.
Bit similar to how everyone misunderstands the size of Africa. Here's a nice toy to play around with for a couple of hours: https://thetruesize.com
So it makes sense to compare the US to Europe as a continent. Got it. What kind of criticism have you read that is wrong due to a misunderstanding of the scale of the US?
> What kind of criticism have you read that is wrong due to a misunderstanding of the scale of the US?
The main one is just not understanding how difficult transit and logistics is here. I've heard British people complain that we should just put high speed passenger rail all across the country like they did while not realizing that their country is literally 1% of the size of the US and more than ten times the population density.
The most sadly hilarious one I see fairly often is Europeans planning vacations to the states and intending to drive across the country in a few days so they can see all the big landmarks on the east and west coasts. It takes a lot longer than they realize.
US is more dense though (going by www.worldometers.info). I think these explanations “why we can’t have good things” are too simplistic. Ignore rail and fiber for a second, and look at commuter air travel for example: European market is much more competitive and prices are much lower than for comparable flights in the US.
Have you ever looked at how big earth is relative to Jupiter to the sun? And how far each one of them truly are from each other? We're terrible at sense of scale :)
As an American who enjoys soccer, it's crazy when you then overlay the entire football pyramid onto Britain. I don't see how USA soccer (MLS, grassroots, lower leagues ect...) could ever be like the "ideal" of how things are done on the other side of the ocean.
the article does not refer to "Nations" either (the phrase used in the Reuters text is "well-known land masses"). title nitpicking is one of the worst things about HN (and there are many things wrong with this site), imo just use the original title.
Spain & UK - "Country" colloquially; might use the term "Nation" if I needed to be more inclusive/ambiguous
(Understanding that formally, State might in fact be a better term: e.g. it's "Minister of the State" or "Statesmanship" etc; but this is how I'd use them in daily life. ESL, 25 years in Canada FWIW)
State and Country are used interchangeably. The United States, before the Civil War was just that, a union of self governing entities. A nation is a group of similar peoples such as the Nation of Islam or Navajo Nation.
Country and State are synonymous terms that both apply to self-governing political entities. A nation, however, is a group of people who share the same culture but do not have sovereignty.
I interpreted the question to be about common/colloquial usage, not definition.
In colloquial usage, for me, state and country are not typically used interchangeably, and are fairly asymmetrical: i.e. I'd never call Nebraska a Country. I'd much more commonly call Netherlands a country, and only call it a state in formal political discussion.
https://cimss.ssec.wisc.edu/satellite-blog/images/2022/01/22...
(it take a few seconds to load, but I believe this is one of the most incredible things I've ever seen).