Althouse: "The phrase cold lava is a translation of the term 'lahar' in Indonesian and Tagalog. Temperatures range between 0°C and 100°C..."

১৩ মে, ২০২৪

"The phrase cold lava is a translation of the term 'lahar' in Indonesian and Tagalog. Temperatures range between 0°C and 100°C..."

"... according to how they are formed, but are typically below 50°C [122°F], according to several academic reports on the phenomenon. A moving lahar resembles a 'roiling slurry of wet concrete' that can grow in volume as it incorporates other debris in its path, said the US Geological Survey."

From "'Cold lava' sweeps villages near volcano, killing 41" (BBC)("I heard the thunder and the sound similar to boiling water. It was the sound of big rocks falling from Mount Marapi").

২২টি মন্তব্য:

BUMBLE BEE বলেছেন...: OMG! Global Warming causes volcano eruptions, just like Vesuvius did!
Environmental change, trust the science.; ১৩/৫/২৪, ৬:৫৪ AM
Dave Begley বলেছেন...: Climate change.; ১৩/৫/২৪, ৭:১৬ AM
MadisonMan বলেছেন...: If I recall right, a chief fear with Rainier is Lahars.; ১৩/৫/২৪, ৭:৩৫ AM
Mike of Snoqualmie বলেছেন...: Mt. St. Helens sent lahars to mow down the forests around it and down the Toutle River. Harry Truman (not the president) was swept away along with his cabin on Spirit Lake. He refused to leave.; ১৩/৫/২৪, ৭:৩৯ AM
RigelDog বলেছেন...: I read this brief article carefully. It's mendacious because they weave probably true facts tied to human activity (human development can change the flow of waters such that more flooding and mudslides occur and more people are living in harm's way) with general facts such as the occurrence of heavy rains in this tropical area and volcanic eruptions. Climate change (murmur murmur) storms (murmur murmur) climate change (murmur murmur) great now the volcano is erupting after heavy rains etc. They never actually SAY that climate change has caused this flooding and the volcano to erupt, but that's what a casual reader will take away from the article.; ১৩/৫/২৪, ৭:৫০ AM
John henry বলেছেন...: "cold lava" - a mixture of volcanic material and pebbles that flow down a volcano's slopes in the rain

First time I've heard of cold lava. From the definition given and the video it looks like a common mudslide

Destructive and horrifying, absolutely.

Calling it "cold lava" instead of mud seems like fake news, trying to gin up fear to get clicks

Sounds like bullshit

John Henry; ১৩/৫/২৪, ৭:৫১ AM
The Real Andrew বলেছেন...: The first time I heard the term “lahar” was regarding the Nevado del Ruiz eruption in Colombia in the 1980s. It was lahars (as opposed to regular mudslides) that wiped out the village of Armero. More than 20,000 people died. One of them was Omayra Sánchez, the teenage girl who became famous because of her tragic photo.; ১৩/৫/২৪, ৭:৫১ AM
The Real Andrew বলেছেন...: এই মন্তব্যটি লেখক দ্বারা সরানো হয়েছে।; ১৩/৫/২৪, ৭:৫২ AM
The Real Andrew বলেছেন...: এই মন্তব্যটি লেখক দ্বারা সরানো হয়েছে।; ১৩/৫/২৪, ৭:৫৩ AM
Quaestor বলেছেন...: The comparison to wet concrete is apt because there are some subtle and counterintuitive physical properties in operation. So, what is wet concrete? Essentially it's a mix of fine mineral particles suspended in a fluid, specifically water. Suspension is not buoyancy. If buoyancy were in operation those fine particles would settle downward under the influence of gravity and the concrete wouldn't set, it would just return to its previous state. Imagine a bucket one-third full of common beach sand. Next, we add sufficient water to fill the bucket, and then we stir. By stirring we've introduced kinetic energy to the system, allowing a situation that overcomes buoyancy -- temporarily. The sand, which is denser than water, is in suspension and no longer concentrated in the bottom of the bucket. Entropy assures us us that the kinetic energy, which is heat, will achieve equilibrium with the wider system over time, the t-naught term in all thermodynamic expressions. The sand settles down and we have the expected situation again that we see in the sea -- sand on the bottom, water on the top. In the case of concrete, there's more energy involved than a simple stir. Some of the particles are hydraulic cement which undergoes an exothermic reaction with water, allowing the formation of crystalline fibers that support the chemically inert aggregates against the influence of thermodynamic equilibrium (entropy) for quite a long time from the perspective of human existence (ask the Romans) but not forever (ask the Russians).

We have something similar in the case of "cold lava" -- particles in suspension in a fluid. In this case, the particles are a mix of boulders and debris in suspension in an effervescent fluid -- water and carbon dioxide mixed to the saturation point. The fluid is just like soda pop. Under confinement in a bottle or within underground voids, the dissolved gas has a lot of potential energy that can translate into a surprising amount of kinetic energy when "uncapped".; ১৩/৫/২৪, ৭:৫৫ AM
Bill R বলেছেন...: There's a 1958 Steve McQueen film, The Blob", on this very subject. The lady front and center is attempting to flee in a knee hugging dress and high heels. She's doomed.

https://thesamlenz.medium.com/the-blob-1958-a-film-ahead-of-its-time-500a42726df7; ১৩/৫/২৪, ৭:৫৯ AM
Aggie বলেছেন...: I didn't pick up unnecessary references to Climate Hysteria when I read it. Indonesia has a history of extremely corrupt (and greedy) leadership and exploitation by foreigners when it comes to natural resources, and the 'haphazard development' label is pretty much spot-on. There are no building inspectors there.

And: Indonesia has several active volcanic systems, which means their vicinity is layered with ash and pyroclastics, laid down quickly, uncompacted, and naturally low-density. This can be a very dangerous type of sedimentation, because the introduction of water via rainfall, together with the steep relief of the accumulated sediments, can result in catastrophic flows. And Indonesia lies in the monsoon belt.

I think the characterization is accurate. In our own hemisphere we have the island of Montserrat, in the Caribbean, which lost a good part of its settled area almost 30 years ago because of eruption - almost the entire southern half of the island. The area is still a forbidden zone, and for good reasons - the unstable ground. You can see the effects clearly on Google maps. In Indonesia, it would have already been re-settled.; ১৩/৫/২৪, ৮:২১ AM
Jamie বলেছেন...: From the definition given and the video it looks like a common mudslide

Thankfully not a common mudslide.

I remember learning about lahars while studying geology. What a horrible way to die - unlike a pyroclastic flow, for instance, in which gas and heat will kill you more or less instantly, a lahar might just trap you in place like the LaBrea Tarpits. (Yes, a mudslide can do this too, but they tend to be more localized, so there are more rescue resources in a smaller area.)

Coincidentally, we just visited Volcan Poas outside San José in Costa Rica a few days ago. It's in an eruptive phase, not too exciting at the moment but still undeniably active. On the day we visited, the sound from the crater was like powerful surf on a rocky coast. Apparently it had been like a thunderstorm a few days before that. Ash coated the vegetation; the fumes immediately made me start coughing. Visitors were limited to 20 minutes at the crater's edge and no other "hikes" were permitted, because the trails didn't have shelters (Poas tends to do ash and pyroclast - boulder - eruptions, along with hydrogen sulfide gas).

My oldest's comment as we left was, "It's only about 10 miles to the capital city - that doesn't seem like a great place to have a volcano." Pause. "You know what I mean." (The funny thing is, he lives in Seattle, where not only is he staring down the barrel of some huge earthquake on the Cascadia fault but also the Big Eruption that will eventually emanate from Rainier.); ১৩/৫/২৪, ৮:৪০ AM
MadisonMan বলেছেন...: I just realized that 'fear' and 'Rainier' rhyme. Appropriate!; ১৩/৫/২৪, ৯:৫৪ AM
Joe Smith বলেছেন...: It's like living in the land of the lost...an Edgar Rice Burroughs novel in real life.; ১৩/৫/২৪, ১০:১৯ AM
Joe Smith বলেছেন...: Cold lava sounds like a great description of when your girlfriend is mad at you.

She's really steamed but won't show it so projects ice queen...; ১৩/৫/২৪, ১০:২০ AM
Owen বলেছেন...: Quaestor @ 7:55: awesome 'planation. Thanks!

It doesn't help the poor people in the way, but it's good to get the science right. BTW, if the lahar is "powered" by effervescence from CO2 outgassing as this stuff emerges from deep underground, will the CO2 (being heavier than air) sweep down the slope and suffocate the oxygen-breathers in its way? I am thinking here of those lakes in Africa with CO2 caught in a metastable state, a layer under the lake waters that if perturbed can overturn and "effuse" with fatal effect.; ১৩/৫/২৪, ১:৫৩ PM
Owen বলেছেন...: Joe Smith @ 10:20: "...steamed...ice queen." Excellent observation. Let me guess there's some real-world experience behind it.; ১৩/৫/২৪, ১:৫৫ PM
n.n বলেছেন...: When the pudding incorporates people... persons, it's called a smorgasbord as a progressive term-of-art and liberal sexual orientation.; ১৩/৫/২৪, ২:১৯ PM
Howard বলেছেন...: I love it when Q turns into a full libtard college professor dipshit. Blue collar men are aware of the concept of a slurry and typically call cement and concrete "mud" when it arrives on a job site. This of course is not different from the mud that is used in well drilling for the purpose of carrying Rock cuttings up from the depths and out of the hole and for lubrication and cooling of the bit.

I'm surprised he didn't go into a full-blown dissertation on the magic of the surface tension of water vis-a-vis the micro plates and/or spheroids of clay and silt that tightly binds the water to the solids. Cement is about 85% silt 10% clay and 5% very fine sand. Sounds like a perfect blend for making mud pies, mud flows, lahars and liquefation. And like drilling mud makes a wonderful vehicle for the transportation of clastic materials.

I have no idea where Q developed his fantasy of some sort of effervescent mud flow. Maybe he is just fondly recalling a champagne enema given to him by his dominatrix.; ১৩/৫/২৪, ২:১৯ PM
Jim at বলেছেন...: If I recall right, a chief fear with Rainier is Lahars.

It's made up of different (weaker) material than St. Helens and not as explosive. It'll simply collapse.; ১৩/৫/২৪, ৫:১৫ PM
RMc বলেছেন...: A good reason not to live near volcanos.; ১৩/৫/২৪, ৭:২৯ PM