SpaceMika

You’ve probably heard of Katla, Eyjafjoell’s more-pronounceable Big Sister. If you’ve seen any of the popnews in response to a press release about a report I haven’t gotten my paws on yet, you’ve probably heard of their history of Eyjafjoell erupting, then Katla erupting even more violently shortly later.

Weirdly, although the press release barely mentions Katla, and even points out that current observations do not point to an imminent eruption, you will get an entirely different story from most media.

Yes, I totally agree with the report that governments should think about the consequences of ongoing eruptions, and figure out a plan in case of Katla erupting well in advance of it being an actual problem. And yes, although vulcanologists can’t pinpoint exact to-the-minute eruption times (and frequently die trying to get the data to figure that out), they’re good at determining that a volcano will soon erupt at least a week, usually more several weeks or months, in advance of the eruption. And no, despite the popnews reports, Katla is not at risk of erupting today, tomorrow, or the next day.

So, how can you tell when Katla, or any other volcano, is going to erupt? Look for changes such as:
- earthquakes (increased frequency or intensity) or volcanic tremors
- ground swelling or cracking (from a full magma chamber)
- more or different gases venting
- changes to local springs (new ones, changes in acidity or chemicals…)
- melting of snow or ice (…which is really easy to see for a glacier-covered volcano!)

And as far as statistics goes: A 3-for-3 eruption pairing history is a good start to a pattern, but it’s a very short history to make solid claims from.

I haven’t said any more about Iceland’s eruptions since everyone else is already explaining everything you need to know.

If you want to hear about the Worst Case Scenario, that’s covered (and I still peg Yellowstone as a more likely candidate for a flood basalt eruption, and that as “not very likely”). If you want to get a more reasoned approach, that’s covered, too. I even like the writeup on how this isn’t a big-league eruption.

The only I feel a need to emphatically restate is about the claims by commercial airlines that a few successful cargo flights count as “empirical evidence” that flying is safe showing a fundamental (and I suspect willful) ignorance of risk. You can’t dodge what you can’t see, you can’t mark a corridor clear when the winds are constantly shifting even a little bit, and you can’t tell me that gobules of glass in a jet engine are an acceptable risk. Ask any aeronautical engineer, ask any airplane mechanic, ask anyone who knows how the mechanics work, and they will agree that this counts as a Very Bad Idea. But allowing flights after wind disperses ash? I’m completely fine with that!

If flights do go out through the ash, I hope their passengers won’t need to remove their shoes for terrorist-screening.

I love orbital dynamics. The math & physics is beautiful, complex, and precise.

I loved orbital dynamics when I first studied it as a wee physicist, but research into surficial cracks on Europa caught my heart and never let go.

Cassini’s mission is extended, and her dance to pull of another 7 years of orbits with less than a quarter tank of fuel is gorgeous.

One of my favourite stops on the first-year disasters field trip is near Whistler, where columnar basalts curve to a central point. Since columnar basalts crack into pentagons perpendicular to the lava’s cooling surface, the standing theory is that this particular chunk of geology cooled under a glacier.

In BC, we’re along a subduction zone. As the oceanic plate subducts (if it’s pulled or pushed is a big debate!) under the continental plate, the oceanic plate melts and the magma fuels volcanism. The basaltic magmas increase in silica content as it passes through (and partly melts and mixes with) the continental plate (andesitic magmas) before feeding volcanism along the coast. Mount Saint Helens and Mount Baker are part of our volcanic chain, with characteristically large, explosive eruptions capable of sending ash into the upper atmosphere (and thus impacting global climate).

Iceland is both above a hotspot and straddling the mid-Atlantic rift zone, a double-source for basaltic low-silica magmas, but in some locations as the melt passes through the tiny bit of continental plate, the silica content rises, and with it, the explosivity of the lava. Iceland was on watch this weekend, fearing a sub-glacial eruption and the resulting explosion of steam, melt, flooding, and mudslides. Instead, a small eruption took place… but in a volcano that has been a precursor to eruptions in a larger nearby volcano each of its past three eruptions (spanning 1,000 years).

This week Melbourne, Australia had an intense, sudden storm, with huge hailstones (up to 10cm diameter observed) and enough rain to flood the downtown core. Although rare, this is not a unique event for Melbourne.

The cold southern oceans have what is called “infinite fetch” — because the ocean surrounding Antarctica is clear of any protruding landmasses, wind can drive waves higher and higher and higher without interrupting coastlines. This means you can get some nasty storms in the few places where land does start peeking into the flow — New Zealand, Tasmania and southern Australia, Cape Horn… — you can get some very nasty storms.

Melbourne is partly sheltered by Tasmania, by the shallow waters of the intervening continental shelf, and by the warm, large Port Philip Bay, but when a strong cold front comes in from the ocean and tangles with the hot, dry air from the interior, severe storms are born. (See pages 45-69 of The Cloudspotter’s Guide for more details on how cumulonimbus form — he writes such an elegant, beautiful description, I can’t hope to improve on it.) This means that sudden severe storms are not uncommon, with particularly severe events occurring approximately once a generation (the last flash flood in Melbourne was in 1972).

If you sliced open a hailstone, you’d see layers of ice, like coloured candy layers of a jawbreaker. A hailstone forms by being tossed up and down in the updrafts and downdrafts of convection within a storm, each trip adding a layer of ice and growing the hailstone. The larger a hailstone is, the more times it’s made the journey — the lemon-sized stones in Melbourne were tossed around quite a bit before pelting the city.

All the recent high-profile earthquakes has mixed with my disaster-training to the point where I need write my quasi-annual “Are you prepared?” post.

Out-of-Area Contact Number
In case of a major regional natural disaster, the local phone network will be overwhelmed. Instead of trying to make a dozen calls to each other all checking in to tell your entire family you’re alright, make one call to an out-of-region contact. This is especially important if your family mostly lives in the same region and can all be affected by the same disaster. Pick someone who would certainly not be impacted (no earthquake in the PNW will knock out phone lines in Alberta; no storm in Florida will swamp the network in Ohio), and if a disaster strikes call in to give your status (are you alright, where you are, etc), and they’ll tell you who else has called in.

If you cannot get through using your cellphone, try text message, then try using the internet (both use different networks and might not be overloaded). If you use a landline, pick up the receiver. If you do not get a dial tone, STAY ON THE PHONE. You’ve been placed in a queue, and you WILL eventually get a dial tone (designated emergency responders jump the queue, so you might be bumped back if it’s immediately after the disaster). Corded phones will work even if the power is out.

If you’re the out-of-area contact for your family, do not make any outgoing calls during the disaster: you do not want your line busy if someone is trying to call in, and you don’t want to tie up their local network with more calls.

Household Plans
Inside your household, you should make a plan of where you’d meet up if a disaster made your home uninhabitable (exe: an earthquake makes the building unsafe to enter, so we’d meet at the local park).

Survival Kits
You can make two levels of emergency preparedness packs — a “Grab’n'Go” bag for 12-hour disasters, and a “Stay’n'Survive” bag for more major catastrophes (72-hour survival). In the Grab’n'Go you should have all the basics you’d want if the house caught on fire — the out-of-area phone number, photocopies of ID, a flashlight, maybe some water & snacks, required medications (spare glasses), something warm (socks, blanket…), very basic first-aid gear (bandages, painkillers…), a bit of cash (at least payphone change) and optionally sturdy shoes (for nocturnal evacuations), a radio, and an external hard drive of photos, thesis-data or other digital-irreplaceables. Communal residents, this is the bag you grab every time the fire alarm goes off and everyone needs to evacuate; it should be near the door, lightweight, and easy to carry (mine’s in a spare backpack).

The Stay’n'Survive bag is more intense, but it’s more things to have around the house than an actual bag. Most municipal emergency plans assume that everyone can independently survive for 72 hours while the official response gets sorted out, so keep a few days of food & water, and for-certain some form of radio.
For more suggestions, check out the Canadian government preparedness site.

Tailor the supplies to the local conditions — staying warm isn’t nearly as important in California as it would be in eastern Canada in the winter. If you don’t know what your local hazards are, here are some resources to get you started:
Canadian natural hazards map & more info
The US doesn’t have a single nice map; instead I offer a maps produced as part of disaster-planning advertising and an interactive map run by the US government, and the link to
more info from the USGS.

If you’re in a major earthquake or are warned of an impending disaster (tornado warning), try to fill your bathtub with water as the system might shut down later. Toilet-tank water is a potable supply of last resort if the water’s already shut done. If you live somewhere with frequent rain (like the PNW), keep a tarp in your Stay’n'Survive gear to collect your own water.

To keep the supplies fresh, rotate food, batteries (if the flashlight/radio need them), and medications out of the bags at daylight savings time each year (it’s also a good time to check batteries on smoke detectors).

Personal Preparedness
In case something happens that leaves you unconscious (even a traffic accident), program into your cellphone an ICE number (“In Case of Emergency”). It’s also a very good idea to have a notecard in your wallet with your name, any life-threatening info (allergies, medications), and that same ICE number (in case your phone is busted). If you’re traveling, it’s a good idea to have both an ICE Home and an ICE local number. ICE is an internationally-agreed acronym that paramedics will check for before continuing on to other common names (like “dad”).

Spin in an office chair with your arms & legs sticking out, then pull your limbs in tight to spin faster. If you watched Vancouver’s Spring Olympics, you saw figure skaters slow down a spin by extending a leg, then speed up by simply withdrawing the leg. This has to do with the moment of inertia — the mass distribution impacts how an object will rotate. When more mass is farther out, things spin slower than when the same mass is closer to the axis of rotation.

When really big subduction earthquakes happen, a thick, heavy chunk of the ocean crust pulls in closer to the center of the planet. This redistribution of mass makes the Earth turn a little faster. After the Chile quake, our days are about 1.26 microseconds shorter than they used to be. This is a permanent change to our global moment of inertia.

But megaquakes aren’t the only impact on the length of a day — the moon provides a gravitational yank to slow us down. Over time, the moon is slowing the Earth through tidal friction, while simultaneously the moon is getting sped up by the Earth (conservation of momentum!), thus moving to a slightly higher orbit. Given billions of years, eventually days and months will be the same length, with the same side of the Earth always facing the same side of the moon. More details on this by the Bad Astronomer.

The earthquake rather overshadowed Polar Bear Day, so I’m going to extend my celebration with a very nice article analyzing the genetic similarities of polar bears and grizzlies, and suggesting that polar bears have rapidly adapted to a changing environment before so might be able to survive the current slow-motion catastrophe.

As promised, this is a look at the chemistry and geology presented in the pilot episode of Stargate: Universe, “Air” (part 1, 2, 3). Our heroes are on a spaceship with a life support system with a non-functional filtration system, and need to come up with a way to sequester the carbon dioxide. They head down to a sandy planet in search of calcium carbonate.

“How come our heroes couldn’t just hold the Stargate open to a planet with a nice, tasty atmosphere?”
That would violate the defined functionality of the Stargate established earlier in Stargate: SG-1 and Stargate: Atlantis. The Stargates prevent the transport of individual molecules, which is handy when the teams connect to space-gates (vacuum on the far side) or submerged gates (water, water everywhere!).

“Wait, if the problem is too much carbon dioxide, how come they’re looking for calcium carbonate? Won’t that just mean they have even more carbon to deal with?!”
Yes, but no.

As carbon dioxide dissolves into water, the water becomes more acidic. Calcium carbonate dissolves in pretty much any acid, and slews of carbonate ions running rampant will form bicarbonate. So, if you chuck a bunch of calcium carbonate into water and add carbon dioxide, the calcium carbonate will dissolve in the acidic water, and all the ionized carbonate will form bicarbonate instead.

This is a well-known phenomena (see here for instructions on how to demonstrate it), and it’s an acceptable hypothesis that shell sediments in the ocean help buffer the acidity from increased carbon dioxide in the atmosphere (see here for an older summary of a Science paper on the topic), so it’s within the realm of plausible science to use the chemical reaction for science fiction.

“…if lime reacts with carbon dioxide to make calcium carbonate, and then calcium carbonate reacts with more carbon dioxide to make bicarbonates, why not start with lime?”
Our heroes didn’t manage to bring the medical-grade lime with them; very unfortunate. Yes, the system would be more efficient if our heroes made lime-enriched water and let that react happily away with the carbon dioxide because then it would sequester carbon twice over, but lime isn’t as easy for novices to identify via field test as calcium carbonate. Calcium carbonate comes as three minerals: aragonite, calcite, and vaterite. They are polymorphs — identical chemicals but different structure — so all of them dissolve in acid. The standard test is to add a drop of 10% HCl, and if it bubbles merrily away, you found calcium carbonate (or drop the rock in the acid for more bubbles!).

“I saw no bubbles. I saw red.”
Eh, red is prettier, or the geologist had prissier field gear because she’s used to alien atmospheres and walking around with acid could be dangerous, or maybe they used something that reacts to changes in pH by going red (cabbage juice turns red in acids (pH below 7), purple when neutral (pH = 7) and blue (pH above 7) or green (pH above 9) with bases), or in the rush to evacuate the base they left behind the hydrochloric acid and had to improvise from the material they had on hand.

“But wait! The chemical reaction is reversible with heat, so why did they hunt for rocks instead of just boiling their old life support goo on the planet?”
Eh, they couldn’t find a cauldron to hold it that didn’t dissolve into muck when handling the goo, or the goo had other chemical reactions going on (you need more than just “less carbon dioxide” to keep a human happy and the montage did include some prep of a white foam) and would do Very Bad Things when heated, or the Ancient goo wasn’t even using this particular chemical reaction to scrub carbon dioxide, or… ie, the chemistry is good and the concepts are good, and the details fall within plausible exceptions for science fiction.

“Why’d they go hunting for calcium carbonate in dried-up lakes or oceans?”
Limestone, chalk, and sea shells on Earth are all high in calcium carbonate; when faced with an alien planet and limited time, the hope that alien sea shells are chemically similar is both plausible, and gives some sort of constraint to guide our luckless heroes.

My first response during disasters is to immediately begin teaching those around me, providing context for interpreting the news stories of far-away horror.

I am nervous of over-representing myself as an expert. I am in training as a Master of Disaster, specializing in catastrophic landslides (anything over a million cubic meters of material), and frequently assistant-teach the UBC first-year natural disasters course. I think about natural disasters a lot more than the average person, but trained seismologists know a lot more about the Chilean quake than I do. Trust them. But if you’re looking for layman’s context, here’s the downlow on Chile’s earthquake.

Geologic Context
South America is prone to subduction-zone earthquakes (one plate diving under another), the deepest meanest earthquakes out there. But there is a tiny blessing — the bigger the earthquake, the deeper it is. With deeper earthquakes, the energy is spread out over a larger ground-surface area, so more places feel shaking but the shaking is less intense than for shallower earthquakes. It’s counter-intuitive, but in subduction zones, smaller magnitude earthquakes are more devastating than larger magnitude earthquakes (Discussion of deeper earthquake over larger area vs. Haiti’s shallower, more focused quake). In Vancouver, we’d have more structural damage from a a shallow magnitude 7 than by a deep magnitude 8 or 9 (and yes, we’re inside the 300-500 year return period on those, so odds are not insignificant that we’ll experience this inside our lifespan).

Building Codes
The most stringent earthquake-safe building codes in the world are in Japan, California, and BC, but Chile’s are very good. The news stories always talk about the absorbing springs in the foundations, but it’s a lot more to earthquake-safe building than that — it’s banning soft stories (ie, parking garages on the first floor) that are prone to collapse, designing windows to break inwards so glass doesn’t rain down in the city core, or grouping buildings by similar natural frequencies so highrises don’t smash together when swaying. Good building codes don’t eliminate damage; they ensure the buildings fail in a way that minimizing injury. Buildings may go lopsided on their foundations, or windows shatter, but the inhabitants will not be crushed. This is why we teach hiding under desks to school children in these regions — we expect the building to survive, and by hiding under a desk you are protected from falling books, lamps, or those fibrous sound-absorbing tiles in classroom ceilings. In places with less stringent building codes, it’s common to teach people to lay down on the ground during an earthquake on the assumption that the roof will collapse, and the farther down you are the better your chances of having something prop the roof and protect you. It’s a technique of last-resort.

In rural areas, it is more frequent for buildings to pop up without legally existing, avoiding the building codes entirely. In Chile, earthquakes happen fairly regularly, so the folk-traditions guiding construction are relatively earthquake-friendly — lightweight materials that collapse easily, but generally don’t cause much damage. (In contrast to places that put on heavy slate roofs that collapse and squish the inhabitants.) In Chile, it won’t be the buildings that kill people. (A brand-new apartment building collapsed, sharply increasing the estimated fatality count.)

Tsunami
The automated tsunami warning network functioned correctly, and the Pacific Ring has a very good monitoring and notification system that should prevent the catastrophe of the 2004 Sumatra tsunami. With tsunamis, we can very accurately predict the locations and times of the wave arrival, but it is extremely difficult to judge the height of the tsunami while it is in open ocean. This is because while only a few centimeters tall in deep water (on a boat in open ocean is the safest place to be in a tsunami), the wave can build to many meters in height as the water shallows. This means it is not infrequent for a tsunami to arrive and be only inches tall, indistinguishable from the regular waves (update: An SFU prof gives a first-hand account of Hawaii’s mild tsunami). The general population gets frustrated for having been evacuated for something so trivial, considering the warning a “false” alarm and are less likely to obey evacuation commands in the future. It’s a really hard job to decide when to issue tsunami alerts. Some media coverage is calling the warnings unnecessary, as the tsunami was very mild, but a former colleague of mine who was observing in Hawaii at the time says the local mood was grateful both for the warning, and for the mildness of the event.

A tsunami is a set of really big waves, so it has that sideways-S shape with a high (crest) and a low (trough). Sometimes the trough hits before the crest, sucking the ocean out and leaving the seafloor exposed, which very few people recognize as a warning of an incoming crest that will inundate the area, so they decide it was a false alarm and go wandering out to poke at the newly-exposed seafloor. If you take away one lesson from this, if you’re ever at a beach and the sea retreats, get to high ground as fast as you can. The biggest wave doesn’t always come first (it’s a bit more likely to be 2nd or 3rd), so don’t go down to the coast after the first wave passes.

For this tsunami warning, the places at biggest risk from tsunamis are the tiny islands that have been developed for tourism, and towns at the ends of narrow inlets. Tourist islands usually have their mangroves removed (the less-developed islands will probably still have their tsunami-absorbing mangroves) and lack the infrastructure and plan for organized evacuations. It’s even harder than usual to judge the eventual tsunami-height in narrow inlets, where the wave gets channeled and can even form a seche (wave oscillating back and forth) repeatedly inundating the coast — this is what happened in Port Alberni, a town at the end of a fjord, during the 1964 Alaska quake.

Landslides
In natural disaster statistics, it’s hard to decide if deaths from earthquake-triggered landslides are included in as landslide or earthquake fatalities. One of the very serious longer-term (months-from-now) risks facing Chile comes from the Andes. The Andes are big, pointy, young mountains with a lot of active volcanism blanketing the hills in loosely-consolidated, slick volcanic ash. The case studies I’ve worked on for Chile all involve (hot or cold) lahars — all that volcanic ash loaded with water traveling 10s-100s of km down valleys, wiping out whole villages. Earthquakes both trigger landslides, and loosen up material so that everything fails in the first rainfall. Everyone’s going to focus on earthquake-recovery right now, and the increased landslide risk will be ignored; with a bit of luck it won’t start raining until after the chaos dies down.

Volcanic Activity
Chaiten (a volcano in southern Chile) has been under red alert since the 17th after increased seismic activity indicated a strong probability of eruption. It could be the big earthquake relieved the pressure, or it could still blow, adding even more ash to the hillsides. As a subduction-zone volcano, it’s of intermediate lava consistency (melting oceanic plate producing basaltic magma, passing through continental plate and becoming more andesitic). This is the same style as Mt. St. Helens — technically less explosive than pipsqueak andesitic cones which are intensely explosive (because the high silica content traps all the gases until they violently explode), but larger volumes of ejecta make that a firmly academic point (since you’d get more ash, more lava, and a larger impact area). The volcano is coastal (meaning no risk of hot lahars devastating downstream towns), and the nearby town is highly practiced at its evacuation drills (although probably overly-comfortable with their nearby monster, so unlikely to actually treat an evacuation seriously), but even just a few years ago when Chaiten started ejecting huge quantities of ash all over southern Chile, it was devastating (both for the cold lahars, and for the ash smothering the crops).

Aftershocks
The aftershock count is currently more than 90 quakes over magnitude 5, which is strong enough to feel like your big brother snuck up behind you and energetically shook your chair. The reason aftershocks happen is that when a fault ruptures (in this case, the subducting plate slipping deeper), the stress builds up at the ends of the fault that didn’t move. Think about yanking on a chunk of fabric (pull on your shirt!) — if you have a solid chunk of anything, and part of it moves and part doesn’t, the part that stayed still will be under a lot of stress to move and stay even with the bit that moved.

In earthquakes, this increased stress can push the built-up stress to the point where that part of the fault ruptures, too, as another earthquake. This will keep happening, with each new event dispersing the stress to farther along the fault until finally the added stress is just under the rupture limit, and the fault holds without slipping. This does mean that over time, places that have had earthquakes are less likely to experience them again (because the stress has been released during the slip), while places that are nearby but not had an earthquake are more likely to have one in the near future (because they’ll have added stress from staying still while everything else moved). The NYT has a nice writeup of how the most recent quake was storing stress build up from the 1960 megaquake.

Additional reading
Telescopes & earthquakes – how the mirrors are kept safe during earthquakes.
Shorter days! as a result of the earthquake.
Crisis Kitchen – updates from the disaster policy experts.
USGS site – all the geo details for this event in one place, including lots of maps
Hackers target tsunami info sites – so careful where you’re clicking in your quest for news