Thinking Big in the Tundra

For the past few years, my time in Kangerlussuaq has been very busy and well organized. Last year, in order to measure over 11,000 lichen diameters and collect over 300 soil samples, I maintained a strict schedule, spending full days in the field and taking only one day off per week (in order to shower, download photos, write blogs, and do laundry). After all, when your field sites are so far from home, and your field season is so short, you better make the most of it.

This year, however, since my soil erosion project is wrapping up, I have had minimal field goals. My focus, instead, has been working with the JSEP students, a group of awesome high schoolers from Denmark, Greenland, and the US.

JSEP students roast marshmallows during their camping trip. Working with these high school students has been a highlight of my field season.

With my mind not consumed by the frenzy of data collection, I’ve had time to think big. I’ve had time to wonder, ponder, question, plan, dream, devise. Time to imagine the science questions I’d ask if resources were unlimited. I’ve been pondering the difference between north- and south-facing slopes, wondering about the hydrology of such an arid landscape, devising systems to monitor the permafrost. I’ve been dreaming of returning here in the winter to look at snow cover, planning experiments to test how well shrubs can colonize eroded patches.

Big thinking is best done with colleagues. Here Rebecca investigates the soils around Kangerlussuaq, getting to know the dry soils so different from other Arctic systems.

Big thinking is very different from the detail-oriented thinking of fieldwork, but it’s just as critical to good science. The creativity required to ask new and interesting questions is a skill often overlooked, rarely taught or discussed. During our fast-paced field seasons, stopping to ponder may seem like a waste of time. Yet how will we devise our next project unless we do? Returning home now, full of new questions and ideas, I’m pledging to always push myself to think big.

I’ve also had more time to sketch during this field season — an activity that helps me to think big by forcing me to look at the landscape from new perspectives.

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Final Field Post!

By the time this blog is posted, we’ll be somewhere over the Southern Ocean, heading toward Christchurch, New Zealand. We’ve had an incredible month here in Antarctica, and it’s been wonderful to share our experiences with you all. Here’s one final blog answering more questions from the students in Windsor, VT. Many thanks to the students who asked such great questions – you have made us think about our experiences from new perspectives. We can’t wait to meet you sometime this spring!

1. How are Antarctica’s Dry Valleys desert similar and different to warm climate deserts here in the US?

It can be surprising to learn that Antarctica is a huge desert, since warm deserts (like in the Southwest US) tend to come first to people’s minds. Although the two landscapes may look very different, there are actually a lot of similarities. For instance, think about the organisms that survive in these harsh environments. Desert organisms need to be able to cope with long periods of time with no liquid water, and they need to immediately take advantage of the water when it returns. In both warm and cold climates, organisms deal with this challenge in similar ways by entering a state called cryptobiosis, which allows them to live indefinitely when conditions are unfavorable. Cryptobiosis is an adaptation that allows organisms in both cold and warm deserts to survive.

Tardigrades, or water bears, seen here through a microscope, are experts at entering cryptobiosis.

Of course, there are many differences between the Dry Valleys and the Southwestern US. One big difference has to do with where liquid water comes from. In the Dry Valleys, the majority of the liquid water running through streams comes from glacier melt during the warm summer months, which is not the case in the Southwest. What do you think might happen to the Dry Valley landscape as the climate warms?

The majority of the liquid water in the Dry Valleys comes from melting glaciers. Here, Taylor Glacier drips in the beaming sun.

2. Is the Commonwealth Glacier, or any glacier different from an ice sheet? What is the thinnest depth of the 1+ mile thick ice sheet?

Yes, glaciers are different from ice sheets! Mostly, it’s a matter of scale. Ice sheets are enormous. There is so much ice that at the top of an ice sheet, all you can see in any direction is a flat white expanse. At the center of an ice sheet, the underlying land surface – the mountains and valleys that would be exposed if there were no ice – doesn’t influence the direction of ice flow. Ice flows out in all directions from the thickest point of the ice sheet, regardless of what’s beneath it. At the edges of an ice sheet, however, there can be areas that are very thin, and mountains can even poke up through the ice.

Although the Taylor Glaciers flows out of a huge ice sheet, it is a valley glacier, since it is confined to the valley between towering mountains.

Valley glaciers, like the Commonwealth Glacier, are much smaller than ice sheets. Valley glaciers, as the name implies, are confined to the space between two mountains, so the local topography is very important in determining where the ice flows. The Commonwealth Glacier is a beautiful example of a valley glacier – it’s narrow between two mountains, and then expands as it reaches the floor of Taylor Valley.

3. In the photo with your tent, how far away is your tent from the Commonwealth Glacier? Also, how far are you from the mountain in the background?

Our tents at F6 Camp are about 1.5 miles away from the Commonwealth Glacier, if we were to take the shortest route. The camp is about 7 to 8 miles away from the tallest mountains you can see in the photo. In order to answer your questions, I had to measure the distances on a map. Scale is really hard to judge in Antarctica. With no trees or buildings, it’s almost impossible to tell how far away something is.

Distances and elevations can be very deceiving in Antarctica. Mount Erebus, the southernmost active volcano, seems so close to McMurdo. In reality, it’s almost 30 miles away and is 12,500 feet tall! I would never guess that by looking at this photo!

4. Do you take water samples along with soil samples? Do you take soil samples under water?

Great questions! Although I’m focused on collecting soil samples, Jess and many other scientists working in the Dry Valleys collect water samples from streams, ponds, and lakes. They analyze these samples to see what organisms live in the water and to determine the nutrients and other chemicals in the water. So yes, we definitely collect water samples.

Jess collects water samples from one of the many ponds in Taylor Valley.

We also collect samples of soils from within the streams. The majority of the soils in the Dry Valleys are very dry, located far away from any body of water. The wet soils near the streams, however, can be very different from the dry soils elsewhere. For instance, we find one particular species of nematode (microscopic worms) that really likes the wet soil, while another species prefers the drier habitats. Finally, other scientists have also collected sediment from beneath the lakes of the Dry Valleys. These lake sediments are really cool because they can be really old, allowing us to determine what the lake was like hundreds and thousands of years ago.

5. Do you need tools to get across wide streams or do you have a plan B?

Having a plan B is always a good idea in Antarctica, where things never go quite according to plan. However, we have easily been able to cross the streams this season in just our hiking boots, since most of the streams are very shallow. A more difficult water crossing is getting onto the lake ice from the shore, across the moat that develops every summer. To get across the moat, people use ladders, planks of wood, and sometimes boats. Just in case, we always carry lots of extra layers, so that we can quickly get dry if we do get wet.

During the summer months, a moat forms between the shore and the lake ice. Scientists crossing the moat to get out onto the lake ice will definitely want to have a Plan B!

6. Do you get to access a helicopter whenever you need it & what type of helicopter is it?

Flying in helicopters is one of our favorite aspects of working in the Dry Valleys. It’s absolutely spectacular to see the mountains and glaciers from the air. We’re incredibly lucky to have access to helicopter support – without it we wouldn’t be able to do our work. We share access to the helicopters with a lot of other people, so there are a lot of steps we have to go through before the helicopter can take us to where we want to go. Three days before we want to travel, we have to fill out a helicopter request form, saying where we want to go, and how long we want to be there. If all goes well, the night before we travel, we’ll get the helicopter schedule, telling us when we’ll be flying and which helicopter we’ll be on. Of course, as with everything in Antarctica, the schedule can quickly change due to weather, mechanical issues, or something else unexpected.

An AStar approaches F6 Camp after a few days of snowy weather prevented all helicopter travel in the valley.

There are two types of helicopters down here, and we’ve flown in both. The bigger helicopter is a Bell-212, which can seat the pilot, the helicopter tech, and 8 passengers in the back. The Bell-212 can carry a lot of weight compared to the smaller helicopter, the AStar. The AStar can fit the pilot and usually just three to four passengers. Both are fun to fly in, but it’s definitely exciting to be in the front seat of the AStar because the windows go down around your feet and the views are incredible.

A Bell-212 is refueled before taking off to take us back to McMurdo.

Many thanks again to all the students for asking such interesting and thoughtful questions!

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**Special Edition** Middle School Antarctic Q & A: Part 2!

Welcome to Part 2 of our Special Edition Q & A

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Thanks to the inquisitive minds of Windsor VT middle school students, we’ve received a whole new supply of Antarctic questions!

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1. What does “avoiding skuas training” look like?

Well, unfortunately it probably sounds way more exciting than it actually was! We didn’t get to practice dodging flying objects, nor did we take turns role-playing an angry Skua (although someone should probably suggest these things for next year). Instead, Skua-avoidance was just discussed as part of our “general safety training”, where they basically told us that these birds will attack if they get the sense you are carrying food. So to avoid giving them that sense, we have to make sure we don’t waltz out of the cafeteria so preoccupied with stuffing cookies in our mouths that we’re oblivious to the giant hungry gull soaring towards our heads. (Yes, we’ve actually witnessed this). Skuas seem to really enjoy taking people by surprise, so our best defense is keeping food hidden and one eye to the sky.

Slightly disappointed that he couldn’t steal our food, this Skua flies off to scrounge elsewhere.

2. Do certain colors mean different things about the plants, such as dying or living?

Great question. Even though it’s a cold dry desert, we see lots of colorful life out here…but most of it is pretty small in size and close to the ground or water. There are no shrubs, trees, leafy or flowering plants, but there are lots of species of mosses, lichens, algae, and bacteria that thrive in these harsh conditions. And these are the types of organisms creating the colorful patches we see near ponds and stream-beds. It’s pretty tricky to tell which are alive or dead because each type has a different set of pigments that give it that unique color. Sometimes these colors can be a little counter-intuitive – where we live in the Northeastern US, we usually see brown, black or orange leaves that die and fall off the tree each fall. But out here there are species that regularly grow with those colors! We see bright orange microbial mats that line the bottom of streams and ponds like a thick carpet. There are dark black leafy mats that look like crusty dead matter, but are actually alive. Some of these organisms grow in very shallow water which makes them extra exposed to sunlight and UV-radiation. This can damaging to them, just like it is to us. So to combat this they make special pigments that act as sunscreen, protecting them from the constant bright light of summer months. And sometimes even the dried and shriveled-up material at the side of streams are actually specially adapted to survive total dryness, so they may come back to life in the presence of water!

Black, red and orange mats lie in a tiny bit of water on the margin of a stream-bed

3. Do different color plants (besides green) have chlorophyll?

This is actually one of the reasons microbial mats are so unique and interesting! The mats we mentioned earlier are built like a sandwich with multiple layers, and each layer contains different kinds of bacteria and pigments. These allow them to maximize their growth even when conditions in the environment change – for example, mats often have protective sunscreen pigments on the top layer (where they’re more exposed to solar radiation), and chlorophyll or other pigments tucked away in the lower layers (more protected from harmful UV radiation). So often when you flip over a bright orange mat, you may actually see bits of green underneath. In fact, some bacteria will actually move up and down within the mat, which may be a way for them to escape intense solar radiation during certain times of year.

A large microbial mat shows off different shades of orange on the side of a small pond

4. How is it able to get sunlight through the ice? And do plants in Antarctica have special adaptations to help them grow?

Yes, ice can definitely reduce the amount of light entering the water. If the ice is thin and clear and the water is shallow enough, organisms with specialized light gathering pigments can still absorb enough to perform photosynthesis. But anything living underwater in Antarctica has to deal with drastic extremes in light (from total darkness in winter and under ice, to ultra high light in shallow ponds in summer). Plus, many water bodies are frozen all the way to the bottom in the winter, freezing these complex underwater structures in place. So to deal with these challenges they have lots of special strategies, such as producing cold-shock and anti-freeze proteins that protect them when the water around them freezes, or using specialized pigments that work extra-efficiently under low-light conditions.

Here at the end of the glacier sits Lake Bonney, which is frozen even on this bright summer day.

5. What is the reason why microbes have certain colors?

The color of microbes is due to the different colored substances inside the cells. Each substance absorbs and reflects different wavelengths of light, and we see the colors reflected. Chlorophyll reflects green light and absorbs the other colors, giving plants their green color. Cyanobacteria are unique because they perform photosynthesis much like plants. These bacteria got their name because they have special pigment called “phycocyanin”, and this gives them that blueish-green color. But bacteria also use pigments for functions other than photosynthesis, like protection against UV or antioxidant activity.

6. Do micro organisms affect the color of the streams? 

Good question –actually any bits of material in the water can affect the stream color as they absorb and reflect light. Often when large amounts of bacteria are healthy and growing they can cause water to look brown or green, although this happens a little less in streams where the water is constantly moving. But in lakes and ponds during the summer this can be dramatic – have you ever seen the water turn green in lakes near you? Because the water is very cold and often nutrient-poor, streams and lakes in Antarctica tend to be pretty clear water. But if you look at the bottoms of water bodies down it’s a different story – that’s where all the colorful mats and microbes hang out.

Long filaments wave like green strands of hair in the shallow water of this Antarctic stream.

7. Why do the microbial leaf mats look like rocks?

Mats come in a wide range of shapes, colors, and sizes. I think some resemble leaves, others definitely look like rocks, there are flat mats that cover the sediment like a big shag carpet, and there are strange tubes that grow vertically like underwater towers. It’s not clear exactly why each of these has such a unique shape and growth pattern, but most likely they all position themselves in a way that maximizes their ability to do things like absorb nutrients and light in their environment. The result is pretty elaborate!

A view of one of many small melt-water ponds in the Miers Valley (can you spot all the orange mats?)

Then, just under the surface of that same pond you get a new perspective – thick mats completely take over, covering the sediments, growing in all dimensions, and creating an underwater microbial city.

8. Do you need a special camera to take underwater pictures?

Yes! I use a GoPro with a waterproof case to take underwater footage. And since the water is very cold, I try to mount the camera onto a long rod so that my whole arm doesn’t go numb in the process!

The GoPro allows me to snap some shots of the underwater life in ponds and streams.

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Thanks again to all the excellent questions & stay tuned for Part 3!

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