Archive for May, 2011

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!