Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.
Showing posts with label glaciers. Show all posts
Showing posts with label glaciers. Show all posts

Saturday, December 19, 2020

Frozen lightning

Regular readers of Skeptophilia will recognize the name Andrew Butters, my fellow blogger over at the wonderful Potato Chip Math.  Andrew and I are so much alike that mutual friends suspect we were twins separated at birth.  Besides both being bloggers, we are both novelists, were both physics majors (degrees we completed despite the fact that, to put it bluntly, we both kind of sucked at it), both have seriously demented senses of humor, and both love weird and arcane science stuff.

It's this last commonality that has earned Andrew mention in Skeptophilia more than once, because he frequently passes along science news articles he runs across, and a good many of these have ended up here.  And today I once again give him my tip o' the hat for sending me a link to a story from Science about some recent research on the topic of fulgurites.

What's a fulgurite, you might ask?  The -ite ending might clue you in to surmise correctly that we're talking about some sort of mineral.  Fulgurite isn't just some ordinary garden-variety rock, though.  Fulgurites are formed when lightning strikes the ground, discharging into soil that has a high mineral (and low organic matter) content.  When this occurs, an electrical potential difference of as much as a hundred million volts is bridged.

This is what physicists call "a hell of a big short circuit."  Lightning releases all the energy stored in that potential in a fraction of a second.  The column of air through which the current passes superheats, generating the light flash and booming shock wave we associate with a nearby strike.

But it doesn't expend all its stored energy on its passage through the air.  As the current dissipates in the ground, it generates so much heat that it melts the minerals in the soil, when then fuse together into a twisted tube of glass that charts the pattern the lightning bolt took once it struck.

Fulgurites [Image licensed under the Creative Commons John Alan Elson, Fulgsdcrb, CC BY-SA 4.0]

The topic comes up because the article Andrew sent me a couple of days ago is about a geologist, Jonathan Castro, at the Johannes Gutenberg University of Mainz, who came up with the novel idea of using fulgurites to chart ancient climate trends.  Fulgurites are often found near mountaintops -- the peak of Mount Shasta, for example, is pitted with them, the rock blackened and scarred from the hundreds of hits the mountain has taken.  Castro found that when a fulgurite forms, it evaporates all the water in the glass chunk formed; the fulgurite then begins to take up water again at a slow and steady rate, so the water content in the pores of the glass can give you a good idea of when it formed.

Not only does this serve to date lightning strike frequency -- and thus give data about the paleoclimate -- it also can be used to time the advance and retreat of glaciers.  A strike onto a thick layer of ice would cause shock cracks and melting, but in short order there'd be no trace left of it.  Once the glacier retreats and exposes bare rock surfaces, though, any strikes would cause the formation of long-lasting fulgurites.

So, fossilized frozen lightning.

Reading about this sort of thing always makes me realize something I never thought about during the years of my abortive attempt to launch a career in scientific research.  Research depends not only on technical know-how and a solid background in your subject, it depends hugely on creativity -- the capacity for coming up with a way of tackling the question at hand in a novel way.  When I read about Castro's use of fulgurites to date the movement of glaciers, my first thought was, "I never would have thought of doing that."  It's not just that I'm not a geologist -- and actually, because of growing up around my rockhound dad, I knew about fulgurites before reading the article -- I just can't imagine being scientifically creative enough to put fulgurites together with glaciers together with water uptake rates by glass and come up with a new lens on the climate ten-thousand-odd years ago.

But I have the utmost respect for anyone whose brain does work that way.  When Andrew sent me the link, my response was, "Okay, that is just cool."  And it once more points at something I've said many times before; if you're interested in science -- even if you were kind of a washout as a physics student -- you'll never, ever be bored.

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If you, like me, never quite got over the obsession with dinosaurs we had as children, there's a new book you really need to read.

In The Rise and Fall of the Dinosaurs: A New History of a Lost World, author Stephen Brusatte describes in brilliantly vivid language the most current knowledge of these impressive animals who for almost two hundred million years were the dominant life forms on Earth.  The huge, lumbering T. rexes and stegosauruses that we usually think of are only the most obvious members of a group that had more diversity than mammals do today; there were not only terrestrial dinosaurs of pretty much every size and shape, there were aerial ones from the tiny Sordes pilosus (wingspan of only a half a meter) to the impossibly huge Quetzalcoatlus, with a ten-meter wingspan and a mass of two hundred kilograms.  There were aquatic dinosaurs, arboreal dinosaurs, carnivores and herbivores, ones with feathers and scales and something very like hair, ones with teeth as big as your hand and others with no teeth at all.

Brusatte is a rising star in the field of paleontology, and writes with the clear confidence of someone who not only is an expert but has tremendous passion and enthusiasm.  If you're looking for a book for a dinosaur-loving friend -- or maybe you're the dino aficionado -- this one is a must-read.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]





Friday, January 17, 2020

Trapped in the ice

Today in the "I've Seen This Movie, And It Didn't End Well" department, we have: scientists digging into glacial ice and finding heretofore-undiscovered species of viruses and bacteria.

Just this week, a paper called "Glacier Ice Archives Fifteen-Thousand-Year-Old Viruses" was released as a preprint on bioRxiv, detailing work by a team led by Zhi-Ping Zhong of Ohio State University.  Here's what the scientists themselves write about the research:
While glacier ice cores provide climate information over tens to hundreds of thousands of years, study of microbes is challenged by ultra-low-biomass conditions, and virtually nothing is known about co-occurring viruses.  Here we establish ultra-clean microbial and viral sampling procedures and apply them to two ice cores from the Guliya ice cap (northwestern Tibetan Plateau, China) to study these archived communities...  The microbes differed significantly across the two ice cores, presumably representing the very different climate conditions at the time of deposition that is similar to findings in other cores.  Separately, viral particle enrichment and ultra-low-input quantitative viral metagenomic sequencing from ∼520 and ∼15,000 years old ice revealed 33 viral populations (i.e., species-level designations) that represented four known genera and likely 28 novel viral genera (assessed by gene-sharing networks).  In silico host predictions linked 18 of the 33 viral populations to co-occurring abundant bacteria, including Methylobacterium, Sphingomonas, and Janthinobacterium, indicating that viruses infected several abundant microbial groups.  Depth-specific viral communities were observed, presumably reflecting differences in the environmental conditions among the ice samples at the time of deposition. 
On the face of it, it's unsurprising they're finding new viruses, because we find new viruses wherever we look in modern ecosystems.  Viruses are so small that unless you're specifically looking for them, you don't see them.

But four new genera of viruses is a little eyebrow-raising, because that means we're talking about viruses that aren't closely related to anything we've ever seen before.

This, of course, brings up the inevitable question, which was the first thing I thought of; what if one of these new viruses turns out to be pathogenic to humans?  The majority of viruses don't cause disease in humans, but it only takes one.  Science fiction is rife with people messing around with melting ice and releasing horrors -- this was the basic idea of The Thing, not to mention The X Files episode "Ice" and best of all (in my opinion) the horrifying, thrilling, and heartbreaking Doctor Who episode "The Waters of Mars," which is in my top five favorites in the entire history of the series.


So I'm hoping like hell the research team is being cautious.  Not that it ever made any difference in science fiction.  Somebody always fucks up, and large amounts of people end up getting sick, eaten, or converted to some horrifying new form that goes around killing everyone.

Lest you think I'm just being an alarmist because I've watched too many horror movies, allow me to point out that this sort of thing has already happened.  In 2016, permafrost melt in Siberia released frozen anthrax spores that sickened almost a hundred people, one fatally, and killed over two thousand reindeer -- after that region not seeing a single case of anthrax for at least seventy years.

On the other hand, it's understandable that the scientists are acting quickly, because the way things are going in the climate, glaciers will be a thing of the past in fairly short order.  Glaciers and polar ice sheets are time capsules, layer by layer preserving information about the climatic conditions when the ice was deposited, even trapping air bubbles that act as proxy records giving us information about the atmospheric composition at the time.  (This is one of the ways we've obtained carbon dioxide concentrations going back tens of thousands of years.)

However, it also preserves living things, including some that seem to retain their ability to be resuscitated nearly indefinitely.  I try not to panic over every little risk, but I have to admit this one has me spooked.  We don't have a stellar track record for caution, but our track record for saying, "Oh, yeah, this'll work!" and then unleashing a catastrophe is a good bit more consistent.

So let's be careful, okay, scientists?  I'm all for learning whatever we can learn, but I'd rather not be turned into a creepy evil being with a scaly face dripping toxic contagious water all over the place.  Call me picky, but there it is.

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This week's Skeptophilia book of the week is scarily appropriate reading material in today's political climate: Robert Bartholomew and Peter Hassall's wonderful A Colorful History of Popular Delusions.  In this brilliant and engaging book, the authors take a look at the phenomenon of crowd behavior, and how it has led to some of the most irrational behaviors humans are prone to -- fads, mobs, cults, crazes, manias, urban legends, and riots.

Sometimes amusing, sometimes shocking, this book looks at how our evolutionary background as a tribal animal has made us prone all too often to getting caught up in groupthink, where we leave behind logic and reason for the scary territory of making decisions based purely on emotion.  It's unsettling reading, but if you want to understand why humans all too often behave in ways that make the rational ones amongst us want to do repeated headdesks, this book should be on your list.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!] 




Wednesday, May 29, 2019

Reality denial

What does it take for people to look at a belief they hold and say, "Okay, I guess I was wrong?"

I ask this because there is still a sizable number of people who call themselves "climate skeptics."  The better term would be "reality deniers."  They tend to fall into two groups -- ones who agree that the Earth is warming up but deny that humans have anything to do with it, and ones who say the Earth isn't warming at all.  Lately, the evidence has been piling up so soundly against the latter claim that more of the reality deniers are ending up in the first class, but honestly, they don't have any more evidence on their side than the ones who deny anthropogenic climate change outright.

It's a little like the anti-vaxx nonsense.  How many studies, with how many thousands of test subjects, do you need before you admit that there's no connection between vaccination and autism?  Or that the risks of vaccination are far outweighed by the benefits?  The evidence is incontrovertible at this point, yet we still have people refusing to vaccinate their children -- which is why measles has been rearing its ugly head in the United States in the past few months. 

Look, on the one hand, I get it.  If you've been vocally in support of a claim, and it turns out the claim was wrong, it's kind of embarrassing to admit it.  Plus, there's the sunk-cost fallacy working against you -- if you've put a lot of energy and time supporting something (or someone), and it turns out your support was unwarranted, it can be less emotionally wrenching to put on blinders and continue your support rather than to admit you were taken in.

But honesty is more important than pride, here.  Especially since in the case of climate change, the long-term habitability of the Earth is at stake.

So at the risk of ringing the changes on a topic I've already beaten unto death:  just this week, three more studies were released showing that climate-wise, we're in big trouble.

[Image is in the Public Domain, courtesy of NASA]

First, we have a paper in the Journal of Glaciology, authored by Regine Hock, Andrew Bliss, Ben Marzeion, and Rianne Giesen, of the Geophysical Institute at the University of Alaska - Fairbanks, looking at the rate of mass loss from glaciers, and finding that just taking into account the smaller land-based ice sheets, there will be a thirty to fifty percent loss in the next eighty years, contributing 25 centimeters to the sea level.

When you consider the fact that this does not take into account the far greater contribution of the huge Greenland and Antarctica ice sheets -- which are melting at an unprecedented rate -- you'd be right to be alarmed.

You'd also be right to relocate away from the coast.

"The clear message is that there’s mass loss—substantial mass loss—all over the world," said lead author Regine Hock, in a press release from the University of Alaska - Fairbanks.  "The anticipated loss of ice varies by region, but the pattern is evident.  We have more than 200 computer simulations, and they all say the same thing...  Even though there are some differences, that’s really consistent. Our study compared 214 glacier simulations from six research groups around the world, and all of them paint the same picture."

The second study, released by the European Space Agency, takes data from the GlobPermafrost Project, using data from the Copernicus Sentinel 2 satellite program to estimate the rate of loss of permafrost from the Arctic -- and are finding that what we are seeing is the beginning of a positive feedback loop.

And don't read "positive" as "good."  Here, "positive" means something that keeps getting worse -- i.e., the "snowball effect."

The problem is, when permafrost melts, it unlocks (literally) millions of tons of carbon that had been stored in the frozen subsoil.  This not only leads to slumping (one of the factors the GlobPermafrost Project measured) but causes the release of both carbon dioxide and methane, each of which is a significant contributor to the greenhouse effect.

If you're not scared enough yet, the main finding of the project is that our estimates of the rate of permafrost melting were too small -- by an order of magnitude.

The last study is the one that should cause the deniers to admit defeat and retreat in disarray -- but probably won't.  The paper, which has already passed full peer review, will be released in the Journal of Geophysical Research in June.  What it does is look at the data from GISSTEMP, one of the main computer models used to predict temperature change, and backpedals the model over a hundred years to see whether it's in agreement with what the global average temperature actually did...

... and found that the model predicted the temperature to within an inaccuracy of 0.09 degrees Fahrenheit.

"We’ve made the uncertainty quantification more rigorous, and the conclusion to come out of the study was that we can have confidence in the accuracy of our global temperature series," said lead author Nathan Lenssen, a doctoral student at Columbia University, in a press release from NASA.  "We don’t have to restate any conclusions based on this analysis."

"The Arctic is one of the places we already detected was warming the most. The AIRS [Atmospheric Infrared Sounder] data suggests that it’s warming even faster than we thought,” said Gavin Schmidt, co-author of a study that supported the Lenssen et al. results.  "Each of [these analyses]  is a way in which you can try and provide evidence that what you’re doing is real.  We’re testing the robustness of the method itself, the robustness of the assumptions, and of the final result against a totally independent data set."

And this result -- like all of the studies that have gone before it -- is unequivocal.

At this point, there's only one question we should be asking the politicians who are still in denial about what we're doing to the Earth.  "What would it take to change your mind?"  Because if what we've already seen from the climatologists isn't convincing, it's hard to know what would be.

And if the politicians answer, "Nothing would change my opinion, my mind is made up," it's time to vote them right the hell out of office, and elect some people who actually care about reality -- and about whether the world our grandchildren inherit will still be habitable.

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In 1919, British mathematician Godfrey Hardy visited a young Indian man, Srinivasa Ramanujan, in his hospital room, and happened to remark offhand that he'd ridden in cab #1729.

"That's an interesting number," Ramanujan commented.

Hardy said, "Okay, and why is 1729 interesting?"

Ramanujan said, "Because it is the smallest number that is expressible by the sum of two integers cubed, two different ways."

After a moment of dumbfounded silence, Hardy said, "How do you know that?"

Ramanujan's response was that he just looked at the number, and it was obvious.

He was right, of course; 1729 is the sum of one cubed and twelve cubed, and also the sum of nine cubed and ten cubed.  (There are other such numbers that have been found since then, and because of this incident they were christened "taxicab numbers.")  What is most bizarre about this is that Ramanujan himself had no idea how he'd figured it out.  He wasn't simply a guy with a large repertoire of mathematical tricks; anyone can learn how to do quick mental math.  Ramanujan was something quite different.  He understood math intuitively, and on a deep level that completely defies explanation from what we know about how human brains work.

That's just one of nearly four thousand amazing discoveries he made in the field of mathematics, many of which opened hitherto-unexplored realms of knowledge.  If you want to read about one of the most amazing mathematical prodigies who's ever lived, The Man Who Knew Infinity by Thomas Kanigel is a must-read.  You'll come away with an appreciation for true genius -- and an awed awareness of how much we have yet to discover.

[Note: If you purchase this book using the image/link below, part of the proceeds will go to support Skeptophilia!]