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cossatot

3,074 karma · joined August 31, 2013

earthquakes and stuff.

rocksandwater.net

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cossatot··on Geothermal heat map of US hot springs
Well, the ones on the summits of Hood and Rainier are just so readily accessible that it'd be a shame not to dip your toesies in.
cossatot··on DeepMind's WeatherNext model achieves breakthrough forecasting cyclones
Forecasting earthquakes via ML should be possible but is very strongly limited by data. We have ~50 years of reasonably good seismological catalogs for most of the world. The seismic cycle (the sequence of major earthquake, reloading, major earthquake on a single section of fault) is generally thousands of years except at the fastest-slipping faults. There are very few sections of faults where we have seismological observations of multiple events, and for >90% of faults, we don't even know when the last earthquake was. There are geologic methods to help with this, but they are labor intensive and often yield error bars of hundreds to thousands of years, because the earthquakes don't produce radiocarbon signatures directly; the geologists use e.g. charcoal older and younger layers as available to bracket the timing, and many faults do not have suitable geologic sites to preserve the earthquake deformation and bracket the timing.

I do think it's possible that thorough exploration of the data that do exist can yield broader patterns that apply to many regions, but earthquake behavior has a lot of complexities and different fault systems may behave differently.

A lot of the hope is for coupling physical simulators to ML and the existing datasets to better understand the physics and then work from there, but this is typically cutting-edge HPC work, which limits the pace of research and the number of researchers.

cossatot··on Shanay-Timpishka, a boiling hot river 700km from the nearest active volcano
>The system is what geologists call a fault-controlled non-volcanic geothermal feature.

These are quite common. Hot Springs National Park in Arkansas is a notable example. Most of the hot springs in Idaho are on fault lines, as are the hot springs along Highway 395 on the east side of the Sierras (though there is Quaternary volcanism in the region, it's not the source of heat), and through much of the rest of the Intermountain West.

This site seems to be unique for both the volume and the temperature of water, though. I'd be curious to know how far away the water originated, and how deep it goes before being heated. The crust in the area is not known to be particularly hot, as far as I know, unlike the Basin and Range of the western US where tectonic stretching and thinning of the crust has brought the hot mantle much closer to the surface and increased the geothermal gradient.

cossatot··on The founder of Craigslist has given away half a billion dollars
We're a century into it at least, even in nominal dollar terms, starting with Rockefeller as the first billionaire.

I don't know whether John Arnold is spread too thin or not, but he's certainly top caliber and does a lot to measure progress before/during investment in various causes (including education). He also seems to be more agnostic on what the most appropriate solution may be at the beginning of the process.

cossatot··on Show HN: TUI-use: Let AI agents control interactive terminal programs
Maybe, just maybe, this is of obvious utility to the many people who have needs that are not yours?

I very regularly need to interact with my work through a python interpreter. My work is scientific programming. So the variables might be arrays with millions of elements. In order to debug, optimize, verify, or improve in any way my work, I cannot rely on any other methods than interacting with the code as it's being run, or while everything is still in memory. So if I want to really leverage LLMs, especially to allow them to work semi-autonomously, they must be able to do the same.

I'm not going to dump tens of GB of stuff to a log file or send it around via pipes or whatever. Why is there a nan in an array that is the product of many earlier steps in a code that took an hour to run? Why are certain data in a 200k-variable system of equations much harder to fit than others, and which equations are in tension with each other to prevent better convergence?

Are interpreters and pdb not great, previously-existing tools for this kind of work? Does a new tool that lets LLMs/agents use them actually represent some sort of hack job because better solutions have existed for years?

cossatot··on EVi, a Hard-Fork of Vim
I use both gvim on linux and macvim on mac for a lot of things--not 'real' coding, typically, but opening and editing scripts and config files, writing in markdown, etc; I'm usually opening these from dolphin or finder. In the terminal, working on real code bases and not scripts, I use neovim. My configs for these have diverged a bit over the years but since the use cases are different, it doesn't bother me.
cossatot··on Ask HN: How to exhaustively search the scientific literature?
Thanks. I've got an OpenAI subscription and tried this in the past, and got a handful of results, but nothing comprehensive. Perhaps it is better now, or I could change the way I ask.
cossatot··on The mountain that weighed the Earth
Interesting...

A few years later, the gravitational deflection of the Himalayas on a plumb line by Airy proved less than expected, which suggested that mountains have 'roots' that extend below them, displacing more dense rock--like icebergs more or less.

I used the gravitational force of the Longmenshan range to calculate the perturbations in the elastic stress field of the Earth's crust in Sichuan province, China, to estimate the tectonic forces in the region, which caused the 2008 Wenchuan earthquake: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/201...

cossatot··on LaTeX Coffee Stains (2021) [pdf]
And wine glass stains are the only way to know your paper has been graded.
cossatot··on Gnome and Mozilla Discuss Proposal to Disable Middle Mouse Paste on Linux
It does on my fedora KDE machine at least. It is probably in the top 5 usability improvements of linux over mac in my world.
cossatot··on CO2 batteries that store grid energy take off globally
Do you think desalinating 10% of the world's ocean water is feasible? What are the energy resources necessary to do that?
cossatot··on Skeena Indigenous Typeface
There were no alphabets in the Americas before European contact. Mayan had written mathematics and hieroglyphics, and some Quechuan speaking peoples had string that had symbolic knots that had some mathematical representation (I don't know if it allowed arithmetic or was just record keeping).

Sequoia developed the Cherokee syllabary (where symbols represent syllables instead of vowels/consonants) in the 1800s after seeing white men reading, and figuring out what they were doing (he spoke little English and could not read it). This is the first real written indigenous language in the Americas.

The Skeena characters shown here are obviously derived from European characters, as was the Cherokee syllabary. I think most written forms of native languages in the Americas are similar.

The Cree have a script which is far from European characters but was nonetheless developed for the Cree by a missionary in the 1800s. The Inuit have modified it for their language.

I don't know much about indigenous languages in the rest of the world.

cossatot··on Ask HN: Why does the US Visa application website do a port-scan of my network?
They are so frequently intertwined
cossatot··on Pre-Sputnik Earth-Orbit Glints
Rocks could be potential sources. Crystals that large are by no means rare, with feldspars being the most common on Earth and perhaps on most rocky planets (quartz is well known of course but I think would be rare without the magmatic fractionation that happens due to plate tectonics, which is perhaps unique to Earth in the solar system.)

Volcanic glass (eg obsidian) is also shiny and by no means rare in the solar system.

Many asteroids are also metallic, and perhaps metal crystals or fracture planes could produce reflectors of the right size.

But maybe it’s just aliens.

cossatot··on Precision mapping tracks woody plant spread across Great Plains grasslands
Don't quote me on this but I think a lot of the change has to do with fire and flood suppression. Certainly on the Konza prairie and similar areas, small trees (post oaks and eastern red cedar) grew in natural fire breaks like bluffs, and individual trees would live for several hundred years. Floodplains would have large cottonwoods which can withstand seasonal inundation but wouldn't necessarily be thick forest otherwise. And the prodigious lightning storms and (throughout the Holocene) burning by native tribes for hunting kept trees off of the uplands.
cossatot··on Ratfactor's illustrated guide to folding fitted sheets
Because it's for your kid's bed. At 3 AM the previous night, they peed the bed, so you got the other one out and put it on, throwing this one in the laundry room. Then, today you washed it but the one on the bed already is still in good shape.

Or, you have sheets of a few different colors, each paired to a comforter with a different weight that is changed seasonally, or biweekly, depending on the preferences of you and your bedmate.

cossatot··on End of an Era
This is evident in his description of programming in his later years:

Time and time again I would send my friend Dave Walker an email declaring that Javascript (or something else) was utterly broken, incapable of executing the simplest program without errors. Dave would ask to see the source code and I would present it to him with detailed notes proving that my code was perfect and Javascript was broken. He’d call me, we’d discuss it, and eventually he’d say something like, “Where did you terminate the loop beginning at line 563?” There would be a long silence, followed by the tiniest “Oh” from me. I’d thank him for his help and hang up. A week later, I’d be fuming again about another fundamental flaw in Javascript.

Many of us are stubborn and will work hard and long, without much positive external feedback, under the assumption that our vision is correct and the audience, if one even exists, is wrong. Much fundamental progress has been made this way: Faraday, Einstein, Jobs, etc. But of course many times one simply is wrong and refusing to see it means throwing years away, and whatever else with it (money, relationships, etc.). It's a hard balance, especially for the monomaniacal without much interest in balance. Finding out how to make solid (public, peer-reviewed, evidence-based, whatever) incremental progress towards the paradigm shift seems to be the way if one can manage.

cossatot··on Satellites Spotting Depth
Similar to the flood analysis others have mentioned, this can be used to create databases of buildings with the number of stories for each, which is important for understanding how each building will respond to various catastrophes (earthquakes, strong winds, etc.) in addition to various non-catastrophe administrative tasks. The other post about finding the depth of oil in oil tanks is actually super interesting to me because the amount of oil in the tank is a huge determinant of how it will respond to seismic ground motions. I had no idea the top sinks with the oil level and am skeptical that it does on all of the tanks but it's cool nonetheless.
cossatot··on Rickover's Lessons
Having read Eric Berger's Reentry about SpaceX and having a few friends who work at Tesla, my impression is that those organizations are not too dissimilar. They are also populated largely by millenial and gen Z people because older workers can't/won't deal with the hours and other working conditions.

Furthermore I think most blue collar American workers, and many white collar workers, are used to the concept of sudden and arbitrary termination.

cossatot··on Instagram 'Error' Turned Reels into Scroll of Murder, Gore, and Violence
This seems to have happened on 26 Feb 2023 as well: https://www.washingtonpost.com/technology/2023/02/26/instage...
cossatot··on By the end of today, NASA's workforce will be about 10 percent smaller
The cuts aren't performance based. They're based on the ease of dismissal.

The voluntary resignations are what they are--I can't fault anyone for taking a good deal, and from what I have heard (married to someone in the government, with many friends as well) no one is being pressured inappropriately.

However, the other cuts are dominantly people who are 'probationary' which means that they are new to their positions, either by being recently hired or in some cases promoted. These people are, actually, on the whole harder workers than those who have been in their jobs for a long time, because they're still being competitive in order to move forward. The non-probationary employees have stronger civil service protections which means that they are harder to fire. This is the major discriminant used to decide who leaves and who goes.

cossatot··on Radiation belts detected around Earth after solar storm
I wonder how much the Van Allen radiation belts are a contributor to the Fermi paradox, i.e. how much they contributed to providing a suitable place for life to originate and flourish, and how rare they are.

The belts themselves are an effect of Earth's magnetic field, which I believe is particularly strong because of flow within the Earth's liquid iron-nickel outer core. (I had long believed that the spinning of the inner core was the primary contributor but given a surface-level skim of the literature that doesn't seem to be the case; convection seems to be more of a driver.)

I think perhaps many otherwise similar planets don't have a liquid iron core, so they may not have the strong radiation belts that shield life from the solar wind. Of course I am not sure what fraction of otherwise-similar planets have liquid iron cores, but Mars for example does not seem to. It is probably a function of the size of a planet (governing the pressure distribution in the interior), the ratio of iron to other elements, the temperature field (a function of the amount of radiogenic elements in the planet and its age), and perhaps other factors. Other planets may not be hot enough to have a liquid iron core at the right pressures, or be too massive (too much pressure) at the right temperatures, etc.

cossatot··on Allstate used GasBuddy and other apps to track driving behavior: lawsuit
No, because the amount of money you have in a bank account accumulates linearly, so you can only pay up to what you have put in. With insurance, you can get a payout more than what you have contributed up to that point, which is necessary for covering catastrophic damages.
cossatot··on Amid cuts to basic research, New Zealand scraps all support for social sciences
I've tought myself a lot of things over the course of my life and am a huge proponent of self-education, but a lot of the 'learning how to learn' had to happen in graduate school. There are few environments that provide the right combination of time, close involvement of experts and peers, the latitude to direct your research in a way that you find interesting and useful within the larger constraints of a project, the positive and negative feedback systems, the financial resources from grant funding, etc.

The negative feedback loops are particularly hard to set up by yourself. At some point if you're going to be at the researcher level (construed broadly), you need help from others in developing sufficient dept, rigor and self-criticality. Others can poke holes in your thoughts with an ease that you probably can't muster on your own initially; after you've been through this a number of times you learn your weaknesses and can go through the process more easily. Similarly, the process of preparing for comprehensive exams in a PhD (or medical boards or whatever) is extremely helpful, but not something most people would do by themselves--the motivation to know a field very broadly and deeply, so you can explain all of this on the spot in front of 5 inquisitors, is given a big boost by the consequences of failure, which are not present in the local library.

The time is also a hard part. There are relatively few people with the resources to devote most of their time for learning outside of the classroom. I spent approximately 12,000 hours on my PhD (yes some fraction of that was looking at failblog while hungover etc. but not much). You could string that along at 10 hours a week, 50 weeks a year, which is a 'serious hobby', but it would take you 24 years. How much of the first year are you going to remember 24 years later? How will the field have changed?

cossatot··on Tsunami Warning for Northern California
Yes, it's a big one in my formative years as a kayaker. I've used the handle in a lot of places and I think you're the first person that's recognized it.
cossatot··on Tsunami Warning for Northern California
I'm a Random Internet Guy who is a professional in the field (earthquake hazards, not tsunamis in particular).
cossatot··on Tsunami Warning for Northern California
Yes, the probability of tsunamogenic landslides do increase during earthquakes, but it's still quite unlikely for an event of this magnitude tens of km from the continental slope; this is why a properly-calibrated tiered system would be better.

The reason that the Palu event is so notable is precisely because it's uncommon. It's also a very different system: the causative fault is running along the axis of a shallow bay that is only a few km across, so even if the landslide did occur, rapid movement of the steep, shallow coastlines would surely have generated a smaller tsunami. It's a geographical and tectonic situation in which at least a minor tsunami is expected a priori conditional upon an earthquake, so a warning system would account for that in principle. (In practice there isn't time enough to mobilize because the tsunami hits while the ground is still shaking). The bay at Palu is like a somewhat larger Tomales bay--an earthquake right there is going to make some waves. Very different situation than one far off shore.

cossatot··on Tsunami Warning for Northern California
Based on the location and focal mechanism of the earthquake (https://earthquake.usgs.gov/earthquakes/eventpage/nc75095651...), this is a strike-slip earthquake on the plate boundary between the Pacific and Gorda/Juan de Fuca plates. Strike-slip earthquakes occur when two plates slide beside each other during an earthquake, usually along a steeply-dipping if not vertical fault. These kinds of earthquakes almost never produce damaging (or even really noticeable) tsunamis because there is no real displacement of sea water by seafloor movement, unlike a thrust or subduction zone earthquake.

The USGS's automated systems calculate the location and focal mechanism/moment tensor pretty much instantly from the seismic network. The system should know that a significant tsunami is unlikely based on the parameters of the earthquake. On the one hand, it's good to be cautious, but on the other hand, a system designed to cry wolf is also self-undermining. Maybe they should have a tiered warning system?

cossatot··on Student rocket group shatters amateur space record
It's space in the SV context, i.e. the competitive arena or market. Americans dominate the space space.
cossatot··on Why did people rub snow on frozen feet? (2017)
What, the Vietnam war?
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