All posts by robertmcgrath

Under the Antarctic Ice

Under the Antarctic Ice

The Thwaites Glacier in West Antarctica is changing rapidly.  If there is any doubt in your mind, NASA has a nice before and after pair of images, from 2001 and 2019 [3].  These images look like winter versus spring on a frozen pond.  But they are the same time of the year (summer), less than 20 years apart.  The glacier is breaking up over the water, and this is happening fast.

These changes could mean that the glacier will flow even more rapidly to the sea, moving more ice from the interior into the sea, where it will melt.  This is a big deal, if that happens.  So there is a major research campaign to measure the bejesus out of Thwaites.

One of the areas of interest is what is happening at the grounding line, where the glacier touches bedrock.  This is a major brake on the ice, halting or slowing the flow out onto the water.  There is evidence that the ocean water offshore is warming, and if that warmer water reaches the grounding line it could lubricate or otherwise change things, releasing the ice to rush on into the (warm) ocean.  Boom!

(The BBC tags this “the Doomsday Glacier” [4], which I think is a bit over the top.  But it’s certainly important.)

In addition to visiting, sensing, and drilling into the ice [4], the research mission included the first robot submarine visit to the actual grounding line [1]. <<link>>  This was a pretty heroic mission, drilling through 590 meters of ice, and remote operating the sub for 15 km round trips.  Wow!

 

The mission captured the first images of the important grounding line.  (The full results will be published soon I’m sure.)

This same team is contributing to the development of missions to explore under the ice on Europa (should we last that long.)


  1. Michelle Babcock, First look under Thwaites Glacier and Kamb Ice Stream, in Life Under the Ice – Blog, January 28, 2020. https://schmidt.eas.gatech.edu/2019-field/firstlookunderthwaitesglacier/
  2. Ben Brumfield, Robotic Submarine Snaps First-Ever Images at Foundation of Notorious Antarctic Glacier, in Georgia Tech News, January 29, 2020. https://cos.gatech.edu/news/robotic-submarine-snaps-first-ever-images-foundation-notorious-antarctic-glacier
  3. Kathryn Hansen, Thwaites Glacier Transformed, in NASA Earth Observatory, February 6, 2020. https://earthobservatory.nasa.gov/images/146247/thwaites-glacier-transformed
  4. Justin Rowlatt, Antarctica melting: Climate change and the journey to the ‘doomsday glacier’, in BBC News – Science & Environment, January 28, 2020. https://www.bbc.com/news/science-environment-51097309

 

Robot Wednesday

More On Deep Carbon

These days we worry quite a bit about the global Carbon cycle, which we clever primates have been blithely monkeying with for a couple of centuries—with impressive results.

But, of course, we mostly worry about the tiny fraction of the planet that we can see because we live here.  Human activities are mostly confined to the surface of land and sea, and the atmosphere.  As we are learning, it is quite within our power to alter the distribution of Carbon and other materials, and thereby significantly change the global climate and life.  Climate and life at the surface

In recent decades, it has become clear that there is a lot more to our planet than the part where puny Carbon-based primates can live.  There appears to be life deep down in the rocks, and also vast amounts of Carbon (living or not) in the Earth’s mantle.  This matters, because all of the human disturbance at the surface are potentially dwarfed by changes rising up from (or sinking down into) the depths.  A slight increase in the transport of Carbon could totally change the surface, overwhelming anything we’ve done recently, or ever could do.

Some of this “deep carbon” is in soils, some of it is ocean sediments, and some of it is in the rocky mantle.  The latter is under intense heat and pressure, but that’s about as much as we really know.

How does chemistry work down there?  This is a hard problem because we cannot visit or sample with instruments.  In fact, we can’t even simulate the conditions with current technology.

This winter researchers at the University of Chicago report new computational simulations of how ions and other molecules work in water at these high pressures [2].  This heroic work is based on “first principles”, i.e., quantum theory.  We can’t actually experiment with these molecules, but we do have solid theory.

The basic idea of the initial work is to characterize the spectroscopy of these molecules in solution, which can be used to interpret and extrapolate measurements we can make.  I.e., we can measure spectra from nature, but interpreting them requires understanding of the physics of the source.

[Caveat: I do not understand the theory or methods discussed in this paper.  I’m taking it all as read.]

The study finds that there probably is more Carbon than earlier geophysical models computed. I.e., there is even more Carbon underground that estimated, which presumably can move out to the surface and in from the surface.

“The results obtained here for the γ ratio imply a higher concentration of bicarbonate ions than previously considered”  ([2], p.5)


I love these first principle computations, because they use technology I helped develop in small ways.

I don’t understand the physics, but I do understand the computation. This computation used a cluster of linux systems (640 processors, 1TB memory), which runs open source science code in parallel.  Between Moore’s law and the parallel software we developed in the 80’s and 90’s, it is now possible to actually compute the theoretical behavior of several dozen atoms.  Wow!

“There are 62 water molecules and one Na2CO3 or NaDCO3 molecule in the cubic simulation box with periodic boundary conditions. “ ([2], p. 5)


  1. Emily Ayshford, Simulations identify missing link to determine carbon in deep Earth reservoirs in Pritzker School of Molecular Engineering – News, February 10, 2020. https://pme.uchicago.edu/news/simulations-identify-carbon-earths-mantle
  2. Ding Pan and Giulia Galli, A first principles method to determine speciation of carbonates in supercritical water. Nature Communications, 11 (1):421, 2020/01/21 2020. https://doi.org/10.1038/s41467-019-14248-1

 

Extinction is an Opportunity

One of the problems with the history of mass extinctions is the definition of the very concept itself.  It’s easy enough to define something like the extinction of the Dodo, where we have a distinctive animal, and we know the population went down to zero.  On the other hand, Homo neaderthalis is “extinct”—except some of the genes persist in the genome of Home sapiens.  So, the phenotypes aren’t seen, but the genome still exists, at least in part.

And then there is the episodes of “mass” extinction, when a lot of species die out at the same time.  We have evidence of five such catastrophes in the history of the Earth, and we are working hard to implement a sixth extinction. The problem is, these events are known from the fossil record, which is hardly complete.

So, yeah, a lot of big dinosaurs died out after the Chicxulub impact.  So did other species, including plants and other animals.  There is evidence that a lot of the coral and plankton died out, too.  Of course, other species survived, including the ancestors of mammals and avian dinosaurs.

But we really don’t have much information about things that don’t leave fossils.  How did fungus fair?  Insects?  Microbes in general?  What about cave dwellers?  Extremophiles that live deep underground?  Tubeworms living at ocean vents?  These species wouldn’t necessarily be as vulnerable to the impact and ensuing nuclear winter.

When we read about “most life being wiped out”, is this really accurate?  Or do we mean, “life that is similar to us”?  And if many species are wiped out, others may be advantaged.  A “mass extinction” is certainly a big event, but to some extent it is may be a “decapitation”, wiping out dominant species, and paving the way for others.

This month researchers report further examination of the drill cores collected by the IODP from the Chicxulub crater [2].  The new study focused on what happened after impact, as the surviving life recovered.  The focus of this study are traces of organic molecules, which are markers for bacteria, including cyanobacteria.

And the results are…interesting.

First of all, not everything died. Second, life came roaring back, right away!

There is a clear layer of debris that was likely left by tsunamis and by water returning into the really big hole.  But above that level, there is evidence of cyanobacteria, blue green algae which characteristic live in low oxygen conditions.  So, in this reeking still hot crater, under soot blotted skies, highly acidic water leaked in—and the cyanobacteria were on it!

At first, there was only a little pond scum, struggling in the dark.  But within a couple of hundred thousand years it looks like there were a lot of algae mats, growing great guns.  And there were layers of oxygenated water, too.  With other species thriving on the abundant nutrients washed down from the devastated continents.

“The nascent Chicxulub crater basin was accompanied by major transitions in nutrient and oxygen supplies (periods of euxinia) that shaped the recovery of microbial life.”   ([2], p.4)

OK, the cool dinosaurs were gone, and the lovely exotic plant scape was charcoal.  And the reefs and fishes were dead, too.

But there was plenty of life.  And, by gum, with all those showboat dinosaurs out of the way, there was space to grow!

Which goes to show that it takes more than a mere planet-cracking impact to wipe out “all life” on Earth.

On the other hand, the top species were definitely bumped off, drowned, burnt, smothered and starved.  It took hundreds of thousands, and millions of years for things to recover to a similar state (i.e., lots of big, cool looking animals and fish).

So, yeah, the Anthropocene extinction probably won’t wipe out all life.  But it will surely do us to death, and it may take hundreds of thousands of years to recover from the massive impact of the human explosion.


  1. Shannon Hall, Asteroid That Killed the Dinosaurs Was Great for Bacteria, in New York Times. 2020: New York. https://www.nytimes.com/2020/02/01/science/asteroid-dinosaurs-crater-bacteria.html
  2. Bettina Schaefer, Kliti Grice, Marco J. L. Coolen, Roger E. Summons, Xingqian Cui, Thorsten Bauersachs, Lorenz Schwark, Michael E. Böttcher, Timothy J. Bralower, Shelby L. Lyons, Katherine H. Freeman, Charles S. Cockell, Sean P. S. Gulick, Joanna V. Morgan, Michael T. Whalen, Christopher M. Lowery, and Vivi Vajda, Microbial life in the nascent Chicxulub crater. Geology, 2020. https://doi.org/10.1130/G46799.1

 

Book Review: “Interior Chinatown” by Charles Yu

Interior Chinatown by Charles Yu

I read How to Live Safely in a Science Fictional Universe (2011) when it came out.  It was OK, but frankly, I don’t remember it very well.

Interior Chinatown is a totally different animal.  Formatted like a screenplay, Yu reifies the social roles he sees in America as literal roles in a movie.  The movie may be in our heads, or in everybody’s heads (thus, the “Interior” in the title.), but the effects of living out fictions about ourselves and others are very real.

In particular, Yu wants to critique the American experience and ideas about Americans with Chinese and other Asian heritage.  As with anything to do with race in America, it’s an ugly mess, and has been for a long time.

As a real life screenwriter, Yu frames a lot of the ideas in terms of how Asians appear in popular film and TV.  “Asian Man”.  “Pretty Asian Woman”.  “Dead Asian Guy”.  And the pinnacle, “Kung Fu Guy”.  No matter who you are, where you were born in America, how smart you are, how good your grades; you are cast in one of these parts, and that’s it.  And you must speak in a stupid Hollywood accent, or else it’s “weird”.

And all these characters only live, can only live, is the weird, twisted scene that is set CHINATOWN, INTERIOR, GOLDEN DRAGON, etc.  This place is only a few blocks long, but there is no exit.

The point—and he does seem to have one—is to strive for “something more”. He addresses this to himself, as he strives to graduate from the pointless distinction of “Kung Fu Guy” role, to the vastly more meaningful role of “dad”. But, of course, we all should strive for something more, more and better to each other (and ourselves).

For history buffs, Yu includes a bit of splainin’ about the weirdness that is “Chinatown”, as well as the preposterously outrageous anti-Chinese laws our great country actually enforced until recently.  Racism mostly makes no logical sense except as pure exploitation, but the laws about “Chinese” people are doozies, even for America.

He also shows us the sick, twisted theme park that is “Chinatown” in America.  I’ve never been especially fond of “Chinatown”, and now I see that there was really good reason.


For an anti-racism tract, this is remarkably readable.  I don’t think you even have to accept all of Yu’s diagnosis to get his point.  And you certainly don’t have to care about popular culture as deeply as Yu does to get his point.


  1. Charles Yu, Interior Chinatown, New York, Pantheon Books, 2020.

 

Sunday Book Reviews

Book Review: “Highfire” by Eoin Colfer

Highfire by Eoin Colfer

Prolific author Eoin Colfer has written a lot of imaginative fiction, a lot of it for young adults (of which I have read little).  I gather that this is the first novel in a while from him, and aimed for “adults”.

The titular Highfire is Lord Highfire, an ancient Wyvern, possibly the last living dragon.  The secret to survival is staying away from people, so Vern (as he styles himself) has been living in the Louisiana bayous outside of New Orleans.  As you might expect, it’s getting harder and harder to stay hidden, even in the swamps.

Whether he wants it or not, people are going to find him.  Good people and bad people.

Young Everett “Squib” Moreau accidently crosses paths with Vern, who generally eliminates such loose ends. But Squib gets a chance to serve Vern, and when the dragon attracts the attention of a really nasty bastard, everyone is soon tangled in some bad stuff.

Dragons are dangerous but not indestructible. And knowing a dragon may be cool, but it also attracts danger.   So things get a lot more interesting than anyone really wants.

As we would expect from Colfer, it’s a great story, the characters are charming, and the dialog is witty.  I really enjoyed it.


  1. Eoin Colfer, Highfire, New York, Harper Perennial, 2020.

 

Sunday Book Reviews

Drones For Solar Farms

OK, let’s combine some of my favorite things, UAVs and Solar Power installations, to get…Percepto.

Over the past few years, I have had a few ideas about drones and PV, most notably some cunning ideas about using drones to sweep snow and other debris from roof tops.  (Shh!  Don’t tell anyone.  I’m still working on it.  : – ))

But I really didn’t know what autonomous drones would do for solar farms, per se.  So I was interested to read about Percepto’s offerings [2].

Percepto aircraft come in a box, and have visual and IR cameras.  The software manages the camera data, steers the UAV, and can use AI to analyze the data.

The main point of the solar power farm version, of course, is to continuously monitor large arrays out in the field.  In the case of solar arrays, the drone system can identify malfunctioning panels and infrastructure, as well as intruders and other anomalies.   PV arrays would seem to be particularly juicy targets for aerial monitoring, since they are exposed, static, and generally very regular.  Learning to recognized a solar panel should be easy for AI!  (Hint:  look for arrays of rectangles, absorbing a lot of light.)

I can see that this kind of autonomous inspection could be both cost effective and very thorough.  The drone won’t get tired or bored, and can fly 24/7 (weather permitting).

All of this is important for operators who want to build really big solar farms.   I guess you know if you need it.

I’ll note that Prcepto’s technology is also sold for other industrial uses, to monitor infrastructure of many kinds.  The solar farm isn’t a particularly unique application except it’s probably easier to implement that other types of infrastructure.  (Basically there are no moving parts, the processes are really simple, the geometry is pretty much a 2D layout.)

So, yeah.  Autonomous Drones!  Solar Panels!   Can we work in Blockchain, too? : – )

Actually, the main thing is found here is that it is all so boring, because it all makes so much sense.  Of course, you want to continuously monitor your huge PV array.  Of course, aerial monitoring is a good way to go.  Of course, you don’t need a large or occupied aircraft to survey it.

So, obviously, you want something like this Sparrow system from Percepto.

And there it is.

If you need it, you know you need it.


PS.  It would be cool to have a stripped down open source version of this kind of thing, suitable for periodic inspection of home and other rooftops.   The requirements are way simpler, but I doubt the economic payback is enough for a business.  But it could be a great PR thing.  “Monitor your home PV with the same technology as leading utilities use.”


  1. Ariel Avitan, Autonomous drones make solar projects more productive, cost-effective and secure, in Solar Power World Online, January 30, 2020. https://www.solarpowerworldonline.com/2020/01/autonomous-drones-make-solar-projects-more-productive-cost-effective-and-secure/
  2. Percepto, Autonomous Drones for Solar Farms. Percepto BR-7-01 01/2020, 2020. https://percepto.co/solar-energy-industry/

Iceberg A68 cruising out to sea!

A68 calved in 2017, and edged very slowly up the coast.  In the last year, she has really picked up the pace, covering roughly 500 km in the last 13 months, which is about 50 meters / hr,  something like 1 / 3 mph.  Not bad for an island!

From [1]. Image credit: S.BEVAN/Swansea University

She is about to enter the open ocean, which will mean a lot more stress from wind and wave, and will probably lead to a big breakup.  Soon there will be a whole flock of smaller, but still very dangerous, bergs.

The BBC reports that there are two more large bergs splitting from Antarctic glaciers, part of what may be a speed up of the ice flows into the ocean.  If the big glaciers begin to move to the sea faster, shedding more bergs, this probably indicates a loss of ice mass on the continent, and eventually to rise in the sea level.

Glub!


  1. Jonathan Amos, World’s biggest iceberg makes a run for it, in BBC News – Science & Environment, February 5, 2020. https://www.bbc.com/news/science-environment-51389690