Archive for the ‘Fieldwork’ Category

A good week for defense

January 19, 2015

I successfully defended my dissertation last Thursday! Defense title: “Measured and modeled albedos of sea-ice surfaces on the oceans of Snowball Earth.”

Here’s how I summed up my talk:

A planet orbits round a yellow sun
Light years away or megayears ago
Its seas are dark, its continent is dun
But brilliant sea ice sets its pole aglow

Its CO2 drops dangerously low
Tendrils of ice reach from the polar caps
That sparks a feedback: oceans turn to snow,
Glaciers push in to close off any gaps

The oceans roiled with countless living cells
Who learned to take their energy from light
Now locked beneath the cold of Dante’s hells
They starve; how long must they endure this night?

Why has this happened, and by what device?
To know, we must investigate the ice.

As sea ice freezes, tiny drops of brine
Are trapped between the quickly forming plates
When cold enough, their molecules align
Into sodium chloride dihydrates

The solid crystals catch and scatter light
Reflect it back, refuse its energy
And I myself have quantified how bright
The surface of the sub-eutectic sea

And in our lab we’ve watched salt ice sublime
With instruments ingeniously designed
The secrets of another space and time
Unfold beneath my models and my mind

This is my work; I hope you will agree
That it is worthy of a Ph.D.

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The Story of Glacier Joe

November 28, 2012

Written at the request of the President of the International Glaciological Society, for the 2012 IGS meeting in Fairbanks. In the style of the classic The Cremation of Sam McGee by the great Robert W. Service.

The Story of Glacier Joe

There are strange things done ‘neath the midnight sun
   By the folks who study ice
They’ll spend hours of time on a glacier climb
   Just to check on some strange device.
With their crampons donned they ascend beyond
   The realms where sane folk go
Yes, they’re all bizarre, but the oddest by far
   Was the one called Glacier Joe.

The letters I.D. marked his sole degree–
   “That’s ‘Doctor of Ice’,” he’d say
From a glacial perch he’d perform research
   In his own peculiar way.

He’d carefully take his ablation stake
   Back home at the start of spring
For the sunny glare might cause wear and tear
   If snowmelt exposed the thing.
He hated to dig, so his snowpit rig
   Was a big overclocked hair dryer
He never would change, though his numbers were strange
   And his notebook often caught fire.

I answered an ad for a glacier grad
   That’s how I joined Joe’s lab
He’d heard some stories ’bout inventories
   And wanted to take a stab.
Our first sortie was altimetry
   With a stopwatch and big flashlight
But so blindingly fast those light pulses went past
   That our glaciers had negative height.

So next Joe raves about seismic waves
   And runs out to buy T.N.T.
But it came to pass that each change in mass
   Was just what we’d blown to debris.
He thought he’d shoot for the theory route
   With area-volume scales;
So Joe would divide feet-long by leagues-wide
   And end up with volume in bales.

Said Joe, “I guess the I.G.S.
   Are a bunch of clever sots,
They’re hosting some sym-pos-i-um
   So I’ll go expound my thoughts.”
He showed fifty-six slides dense as bricks
   With text in Comic Sans
And spoke with such flair that the Session Chair
   Dragged him offstage with both hands.

We went for beers with our glacial peers
   And they told us of what they did
And all this news made Joe enthuse
   Like a sweet-shop-dwelling kid.
So back we went to our field tent
   To add to our data stores
Energized anew, we both set to
   The task of drilling cores.

We drilled and cored and dug and bored
   ‘Til our hands were sore and tired
And I strained my eyes to analyze
   The samples we acquired.
Well, day by day went on this way
   And the data rose like the tide
But nary a bit of that data would fit
   No matter how hard Joe tried.

“I’ll never know how the glaciers flow,”
   Joe cried out in despair
“From the top to the bed, it’s all over my head–
   I tell you, it just ain’t fair.”
“I know some folks can use full Stokes
   But my models ain’t even one-D.
From densification to surface ablation
   These glaciers befuddle me.”

And after this spiel, Joe turned on his heel–
   And threw himself down a moulin!
With a rope from the sledge I raced to the edge
   But by then he was long gone.
Unhappy and damp I returned to the camp
   And pondered poor Joe’s fate;
Down the hole he’d been flushed to be frozen or crushed
   It was awful to contemplate.

But later that night in the fading light
   I awoke to a bellow grand
Like a trumpet brass from a deep crevasse
   Saying “NOW I understand!”
“It’s all so clear from way down here!”
   Exclaimed the voice with glee.
“Every wax and wane of stress and strain
   Is an open book to me!”

“I can see each kernel of snow and firn’ll
   Become a crystal grain
And each drop of melt makes its presence felt
   In the branched subglacial drain.”
The ice folks say that to this day
   A student or a seeker
Can strain an ear, and faintly hear
   From beneath the ice: “Eureka!”

There are strange things done ‘neath the midnight sun
   By those studying ice and snow
Yes, they’re all bizarre, but the oddest by far
   Was the one called Glacier Joe.

Ice roads and igloos

July 11, 2011

Ice melt to close off Arctic’s interior riches: study

One of the things I find interesting about ice is its use in engineering. Ice and snow are actually fantastic building materials for certain purposes–mostly due to their cheapness and ubiquity, but sometimes also because they have useful physical properties. You may have heard of Pykrete, the mixture of ice and wood pulp that was proposed as a potential material for aircraft carriers. The wood pulp increased the strength of the brittle ice; it also reduced its thermal conductivity, slowing down melt. But apparently the fact that ice flows under its own weight, combined with the fact that such a carrier could only be used in cold weather or with massive refrigerating apparatus, doomed the project.

In cold climates, however, ice is a natural material for all kinds of things. For instance, the ice roads made famous by the show Ice Road Truckers and whose impending loss is bemoaned in the article at the top of this post. Or the ice pier at McMurdo, mentioned in this post and shown below being trimmed to size by several explosive charges:

BOOM

Ice structures needn’t be solely functional. For one thing, it’s a popular sculptural medium. You’ve also probably heard of ice hotels like this one in Sweden or this one in Qu├ębec. Despite its beauty, though, ice isn’t the most functional material for living quarters; it conducts heat too well. For dwellings, you want something with good insulative properties: snow!

The most famous snow dwellings are those made by the Inuit people of the high Arctic: igloos. (“Iglu” can actually refer to any type of dwelling, but for my current purposes I’m most interested in the temporary, dome-shaped, snow-and-ice structures.) This webpage discusses igloo technique, including the use of lamps to melt the interior so that it will refreeze as structurally stronger ice. (It is worth noting that traditional cut-block igloos work best with a certain type of wind-packed dry snow that is, I think, much easier to find in the Arctic and Antarctic than in temperate regions.)

But snow shelters are useful for anyone camping in snowy conditions. This chapter of the US Antarctic Program Field Manual (PDF link) describes the basics of several different types of snow shelter. The quinzhee, for instance, used to be a major feature of McMurdo Happy Camper school. The US Antarctic Program approach is to build up the quinzhee by shoveling snow on top of a pile of equipment which is then removed to create a cavity; more traditional quinzhees may involve creating a pile of snow and later hollowing it out.

When I did Happy Camper they emphasized the snow trench as a shelter that could more easily be built by one person, if necessary:

Snug and warm(ish.)

The one disadvantage of a snow dwelling this small is that one is forever knocking snow off the walls and down the back of one’s neck. Igloos and quinzhees are far preferable if you have the time and manpower, not to mention being more visually impressive.

The Voyage of the Endurance

June 11, 2011

Hey guys! I wrote you a song! It’s about the epic tale of survival that resulted from Shackleton’s attempted Trans-Antarctic Expedition; I used this website as a reference for some of the events, or you could read Shackleton’s own book on the experience, South. Be sure to check out the pictures, which are widely and deservedly regarded as the best part of the book.

Sung to the tune of (The Bonnie Ship) The Diamond.

The Voyage of the Endurance

‘Twas early in the century
The world prepared for war
But Shackleton intended the Antarctic to explore.
Some men sail for profit
Some sail for renown
But this one sailed for Science and the glory of the Crown.

Through the icebergs that clash, through the great waves that roll,
The mighty ship Endurance went a-sailing for the Pole.

The whalermen had warned them
That the ice would be severe
They were still above the Circle when the first floes did appear
Still bravely they sailed southward
But soon they were beset
Imprisoned in the heaving ice, but not defeated yet

Through the icebergs…

They whiled away the winter
Drifting ‘cross the Weddell Sea
When finally the sun arose, they thought they’d soon be free
But the mounting pressure of the ice
Was more than she could bear
In just days the stout Endurance was crushed beyond repair

Through the icebergs…

They loaded up the lifeboats
With provisions piled high
They watched her sink beneath the ice as, helpless, they stood by
The men camped on an icefloe
Let it take them where it would
It brought them near an island before breaking up for good.

Through the icebergs…

The isle was cold and barren
Inhospitable to man
So Shackleton devised another daring rescue plan.
He’d sail eight hundred miles
‘Cross the world’s most stormy sea
To the whalers on South Georgia he would make his earnest plea.

Through the icebergs…

A thousand times the pounding waves
Near sank the tiny boat
They lost most of their gear and food, yet somehow stayed afloat
When the party reached South Georgia
Thirst-tormented and sore
They realized the whaler-camp was on the further shore.

Through the icebergs…

They scaled the craggy mountains
And crossed crevasses deep
They stumbled into whaler-camp half-crazed from lack of sleep
The whalers were astonished
When these strange men came in view
Soon Shackleton secured a ship to rescue all his crew

Through the icebergs…

Let Shackleton’s Antarctic fame
For centuries survive
For with all their trials and troubles, every man came back alive!

Ice Sectional Preview

May 2, 2011

Not much time–heading to the airport soon to wing my way home to Seattle–but here are some nice pictures of ice sections, the things I spent long long hours in the cold lab working on. I’ll talk more about the process, and their scientific importance, soon.

Vertical section, from around 10 cm below the surface.


Same section between crossed polarizers to show some of the crystal structure.



Larger, more clearly defined crystals in a horizontal cross section of the core.

Also, because everyone likes charismatic megafauna, here is a Svalbardian reindeer! (“Reindeer” in English means a domesticated caribou, but the Svalbard ones are wild.)

This reindeer is foraging just a short ways from our lodgings.

A Compendium of Measurements

May 1, 2011

So what does a typical day of fieldwork look like, for this trip?

The first order of business is to actually get to the field site, Tempelfjorden. It’s around fifty or sixty kilometers (thirty to thirty-five miles) away from Longyearbyen by snowmobile, which is the conveyance of choice. Snowmobiles have numerous benefits: they’re fast, they can pull good-sized sleds full of equipment, they can deal with a wide range of snow and ice conditions, and they’re loud enough to repel polar bears.

The trip out takes one-and-a-half to two hours, depending on the light and snow conditions; for instance, it’s more difficult to drive fast on days with cloudy, diffuse light because snow features become very hard to see. It’s quite the scenic commute, although snowmobiling is more physically draining than you might expect if you’re not used to it. We arrive around 11 AM, if we’ve planned things right.



Time for a photo break.


Once we get to Tempelfjorden, Bonnie and SvalSteve select a good site for taking measurements–mainly they want something that’s not too close to well-traveled snowmobile routes, since Tempelfjorden is actually a reasonably popular tourist destination. (I discovered yesterday that there are actually daily snowmobile tours out there; it’s kind of cheering to find out that your field site is someplace people pay to go to. And the tourists only spend about eight hours on the roundtrip, but we get to be out doing science for THIRTEEN hours!) Once it’s selected, we get to work putting together the equipment.

Not scientific equipment, but nevertheless important, given that it's difficult to take sea ice measurements from inside a polar bear.

This has been an ambitious trip in terms of the number of measurements we’re trying to take on each day out. We measure snow and ice albedos, using a piece of equipment somewhat similar to the one I’ve used in Antarctica, only smaller and more portable (currently set up so it can be mounted in the Backpack of Science, of which I have a picture around here somewhere.)

Bonnie and Naomi take albedos of the bare ice.

We measure the transmission of light through the ice using several instruments mounted on two different arms, Bonnie’s and SvalSteve’s.

Bonnie's arm. When it's underwater, the foam makes the lower part float upwards so that the instruments are right under the ice, some distance from the hole.

SvalSteve and colleague Mats carrying their arm. It has two different instruments, one for general transmitted light and one for transmitted UV radiation.

We drill a hole through the ice to make a detailed profile of the light at each level within it.

Naomi calibrating the profiler.

We make ice cores to be melted and filtered a few different ways and additional cores to slice thin and put under the microscope.

SvalSteve drills a core the fast way, with a motor.

We dig snow pits (to measure profiles of snow characteristics such as density) and take snow samples so we can melt and filter those too.

SvalSteve and Naomi work on a snow pit.

Phew. By the time we’re done with all of that and have packed away all the equipment, it’s late in the day, and we generally get back to Longyearbyen just in time to rush to a local restaurant before they stop serving food at 11 P.M.

Next: more about how all that equipment actually works, and what we get up to in the lab!

The many qualities of light

April 28, 2011

Yesterday’s fieldwork was bright and hot; it got up to 37 degrees Fahrenheit at one point. Here Bonnie and Naomi prepare to put the under-ice arm (which carries sensors below the sea ice to measure the transmission of light) through a hole we’ve drilled in the ice.

Svalbusiness

April 26, 2011

I really must remember that there are times and places for short sweet blog posts, and that one of those times is during very busy fieldwork days. It’s a bit of a catch-22, actually; there’s so much going on that the number of things I want to write about increases in inverse proportion to the time available to write about them. Our lodgings don’t have Internet, so my usual tactic of forgoing a little sleep to write blogs at the end of the day doesn’t work as well.

So far we’ve been out to the field twice and spent the rest of our time mostly in the lab. Our field site is a fjord about forty or fifty kilometers from town, called Tempelfjorden; we commute there on snowmobiles (“scooters” in the local parlance) which makes for a lengthy but scenic trip. Out on the ice, we make a plethora of measurements and take numerous samples–mostly of ice, but also of the snow on top of the ice. It’s been remarkably warm, near freezing most of the time; I get much colder working in the cold lab to process the samples than I ever do out on the ice making them.

We’re headed out again tomorrow; in the meantime, here are some pictures from our fieldwork.

Svalblog!

April 21, 2011

Hello! I’m writing from Longyearbyen, in Svalbard. I actually got here yesterday afternoon, but was a bit too jet-lagged and befuddled by my ~24 hours of travel (Seattle to Newark to Oslo to Tromso to Longyearbyen) to do much.

I am surprised at how much this place reminds me of Antarctica, with its stark black-and-white scenery. One notable difference is the open water that comes right up to the land. We’ll be visiting some landfast (frozen to the shore) sea ice when we go to the field, but near the town the water is unfrozen. Our host/guide, Steve (not to be confused with my advisor Steve; maybe I will start calling him SvalSteve to avoid confusion), says this is due to warm Atlantic currents. Longyearbyen is slightly further North than McMurdo station is South, but due to its weather patterns and currents it’s notably warmer. Of course, it’s also warm because it’s Spring; the last sunset of the season was the day before we arrived, and a lot of residents will soon be leaving for the Easter holiday.

From Journey to Svalbard

Some Svalbard scenery.

There’s a surprising amount of tourism in this small city. People come to ski and hike and snowmobile and see polar bears; there are several sporting-goods stores near the short pedestrian corridor that serves as a sort of downtown. Snowmobiling appears to be a popular form of transport, with snowmobiles outnumbering cars two or three to one. Rifles are commonplace, since anytime you leave the city you’re apt to run into polar bears. (It’s rare that anyone actually shoots a bear, mind you; it’s very illegal to do it for any reason except desperate self-defense, and even self-defense cases are rigorously investigated.)



Snowmobile + rifle = typical Svalbard.

I’m here helping my colleague Bonnie do a project with the Norwegian Polar Institute–more on that later, as it sounds like tomorrow will be a long fieldwork day (we spent all of today sorting and prepping gear for it.) In the meantime, check out the blog of the other student accompanying us, Naomi to the North.

157 degrees of latitude in 63 days

April 18, 2011

So I’m about to leave again for another session of fieldwork and I haven’t even finished posting the updates from the last one. Embarrassing.

Anyway, on Monday I’ll be leaving for Longyearbyen, in Svalbard, an archipelago and territory of Norway at around 78 degrees North. I’m assisting my colleague Bonnie with some measurements of the optical properties of sea ice in the fjords near there–somewhat similar stuff to what I was doing in Antarctica, although not for the same project (the sea ice we’ll be dealing with there is much warmer and more full of algae than anything we’d expect to find on Snowball Earth, at least based on current models.)

I’m pretty excited about this! The Arctic is very different to the Antarctic, in a lot of ways, and despite growing up in Alaska this will be the first time I’ve been north of the Arctic Circle. While the Antarctic is ice-covered land surrounded by water, the Arctic is ice-covered water surrounded by land, so it’s much less isolated. Land ice and sea ice are very different physically, as well, with land-based glacier ice being quite stiff and slow and clean and orderly compared to chaotic, ridged, constantly-shifting, salty, life-harboring sea ice.
The Antarctic has no land-based predators larger than a tiny worm, whereas in the Arctic we’ll have to keep an eye out for polar bears, a species that has few compunctions about eating humans if given the chance. (I’m told that if we’re on our guard and prepared, we’ve little to worry about.)

I’ll post again when I get there.