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During the 2012 IGERT Field Seminar in Greenland, the all-female cohort 3 was introduced to this promotional video, put out by the European Commission as a part of a campaign to inspire more young women to get involved in science.

The controversial video has since been taken off the European Commission campaign website, but not before sparking some lively debate.  The discussion in Greenland amongst cohort 3 about the video and the role of women in science inspired us to make our own version of Science: It’s a girl thing!.

And so we proudly present:  Science in Greenland: It’s a Girl Thing

What do you think about the European Commission video and our take on women in science?  Despite the controversy surrounding the video, the European Commission has a really cool website for their Science: It’s a girl thing!  campaign.  Check it out: http://science-girl-thing.eu/en.

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Kangerlussuaq is peppered with lakes and ponds, extending all the way up to the ice margin. There are many interesting questions to be answered with regard to these lakes – for example, what are the nutrient inputs? How does the water chemistry vary between each? What is the community composition of aquatic plant and animal life? And how might all of the above parameters be influenced by the surrounding vegetation and geology?

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Setting up to take water, sediment, and plankton samples. Photo courtesy C. Vario.

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The crew finds sea tomatoes settled all over the lake sediment. Photo courtesy C. Vario.

To get at some of these questions, Ali, Chelsea, Stephanie and I headed into the field one last time before leaving Greenland. Together, we sampled four lakes between the town of Kangerlussuaq and the ice margin. These lakes are especially interesting because of the orange, spherical balls inhabiting them, known locally as sea tomatoes. These fascinating organisms are a species of colonial cyanobacteria belonging to the genus Nostoc. Lakes here are highly variable in their abundances of sea tomatoes, with some having no visible colonies, and others supporting hundreds to thousands of colonies.

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High density sea tomato lake.

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Sea tomatoes vary in size, with large colonies reaching the size of a softball.

To capture this density gradient, we sampled lakes at four different sea tomato densities, ranging from no visible colonies, to high abundance (estimated to be thousands of colonies). At each lake, we took samples of (1) whole lake water, (2) lake sediment, (3) zooplankton and phytoplankton, and (4) the sea tomatoes.

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Steph tosses the plankton net into the lake to capture zooplankton. Photo courtesy C. Vario.

Back in the lab, I hope to use these samples to better understand the occurrence and distribution of sea tomatoes, including: what are some of the limits to sea tomato dispersal? Lakes with few to no visible sea tomatoes are often situated next to lakes teeming with them; what limits their movement and establishment to certain lakes, but not others? Do high versus low sea tomato lakes show differences in water and sediment nutrient levels? Many species of cyanobacteria, including other species of Nostoc, produce toxins, but we don’t yet know whether or to what extent sea tomatoes in these lakes are releasing toxins into the system. Further, examining the zooplankton will allow us to ask additional questions about the movement of the toxins through the food web and more generally, about the composition of these arctic lake communities.

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Steph and Jess inspect the fresh plankton net catch. Photo courtesy C. Vario.

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Lively zooplankton dart around the sample jar after being caught in the plankton net. Photo courtesy C. Vario.

*Look for updates soon on what we are now learning from these samples!*

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*written by Ross Virginia*

Today was the First Annual Running of the Muskus (Musk ox) in Kangerlussuaq. Conceived by Audrey Jo Mills and her friends at Polar Services and the community members, this 5K and half marathon run raised about $3,000 for the local school. My role as a volunteer was to help set up the BBQ that followed the race and to cheer for the finishers, who ranged from IGERTs in panda and unicorn attire to a woman pushing a baby buggy with a beaming passenger. The runners were transported on the road leading to the ice edge with a staggered start to allow everyone to finish at about the same time. The weather was perfect and all runners were accounted for.

Team IGERT claimed first in the women’s divisions for the half marathon and the 5K! (I need to brag here, they are both members of my lab group- way to go Pandas). I’ve witnessed many polar races at McMurdo Station, Antarctica. It’s wonderful to see a new tradition born at Kangerlussuaq. The event brought together scientists, the Air National Guard, and the community for fun and a good cause.

Another great day in Greenland.

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Team IGERT comes together at the finish line!

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An interesting part of the field course for me has been learning about topics that are not part of my primary discipline.  While Jess and Chelsea are well versed in the area of ecology Ali, Lee and I are newcomers to the field.  Throughout our week camping we learned a few principles of ecology including the brown and green food webs and biodiversity.  Learning new material while immersed in Greenlandic tundra was an amazing hands-on experience that I’m sure I will never forget.  In the following, I will go into greater detail about the ecology we learned.

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Exploring the tundra around camp

The Brown and Green Food Webs

The green food web is the food web that I automatically think of when I hear the term.  It consists of plants and the animals that eat them and makes up about 10% of the total biomass.  Two of the keystone species in Western Greenland are dwarf birch (Betula nana) and the willow (Salix glouca).

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Photo of Betula nana

Some of the other species that one frequently sees in the Greenlandic tundra are the blueberry, musk ox, caribou, arctic fox, arctic hairs, and various grasses and sedges.  Another fun species that Matt showed us is the Dryas integrafolia a close relative to the species whose pollen is found in lake cores from the cold Younger, Older, and Oldest Dryas periods.

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Photo of Dryas integrafolia

The brown or decomposer food web consists of dead plants and animals and the various organsims that decompose them.  The brown food web makes up the other 90% of total biomass.  The brown food web recycles nutrients and makes them available for the organisms of the green food web to utilize.

Biodiversity of the Arctic

To develop a better understanding of the term biodiversity we set out from camp and hiked up a hill relatively close to the edge of the ice.  Once there, we all spread out and found a one meter by one meter patch of land to exam.  The purpose of our close examination of such a small area was to count as many different types of plants that we could see.  I saw 12 different types of plants in my plot including but not limited to blueberries (Vaccinium uligonosum), dwarf birch (Betula nana), pussy willow (Salix glouca), one mushroom, three flowering plants, two types of lichen and some moss.

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Two flowers from my plot

Once everyone had totaled up all the plant life they saw in their plot we gathered back together to compare notes.  The average number of species identified by each person in the group was 11.2.  At this point Matt Ayres told us that he has conducted this same experiment multiple times in the high altitude regions of Costa Rica and the average number of species seen by that group was only 9.4.  What was going on?

Isn’t it true that the tropics have the highest diversity on the planet?  Could the tundra really have more diversity?  The answers to these questions come in learning about alpha and beta diversity.  Alpha diversity is a measure of the average number of species in a given area from multiple plots while beta diversity is a measure of total species found in all of the plots examined.  So while the Greenlandic tundra was higher than the Costa Rican highlands in alpha diversity it is significantly lower in beta diversity; ie. the total number of species present in the Arctic tundra is significantly lower than the  total number of species found in the highlands of Costa Rica.

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Jess and Ross examining the species present on the hillside with an awesome view of the ice sheet.

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(Note: This was written on Wednesday 8/8.  We haven’t had a fast internet connection since then!)

Hello from the city of brightly colored buildings, ice bergs, deep fjords, and the seat of the Greenlandic government!  The remainder of cohort III (Lee left us for Thule) safely arrived in Nuuk on Monday morning, after a 1-hr flight on a ~20 passenger prop plane, Dash-7.  The views were so stunning that I don’t think anyone would have objected to a slightly longer flight, except perhaps the man in the window seat next to me who had to deal with my snapping pictures every three minutes or so.

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(Photo: A.Giese)

On Monday, we kept busy by familiarizing ourselves with the central part of the city, the waterfront (rather, one of many), and some internet cafes.  Internet is surprisingly hard to come by here, but the fact that it’s available only at the distant university or in cafes provides a good excuse to indulge in delicious pastries and cappuccinos.  On Monday night, Courtney, Julia, and cohort III were invited for a “girls’ night” at the home of Upaluk Poppel, a Greenlandic woman who studied at Dartmouth two years ago with the Dickey Center’s Greenland exchange program.  It was a rare treat to spend time in a home after so many weeks of traveling, and our frank but light conversations served as a perfect introduction to the culture of our new location.

On Tuesday, we elected to familiarize ourselves with the history of Greenland and its people at the National Museum, which houses an impressive collection of clothing; household and hunting materials telling the story of Greenlanders from the expansion of the Thule Culture more than 1,000 years ago to the present; and the Mummies of Qilakitsoq, made internationally famous by a National Geographic feature in 1985.  Following the museum and a brief lunch, we attended a talk on the proposed Isua Iron Ore Project, which would create an open pit mine roughly 150 km northeast of Nuuk.  The mine is controversial for a number of reasons (environmental effects, influx of foreign workers), though the talk centered around the engineering design of the mine rather than the social issues, which will be the focus of a meeting in late August after we leave.  We heard from a London Mining representative as well as an engineer from the engineering company SNC, and the talk was translated into Kalaallisut, as well.  Not only was the project itself fascinating to hear about (especially because they have to “mine” part of the glacier to access ore), but the dynamics between speakers with different interests were also thought-provoking.  We observed how the project chose to present complicated science and engineering to a general audience.

Following the mining talk, we received our first official Kalaallisut (Greenlandic language) lesson with two students from UChicago working with Lenore Grenoble, renowned linguist and our other professor for the Nuuk segment of the seminar.  TJ and Perry taught us basic phrases like hello, good day, how are you, thank you, yes, and no, which are, respectively: “aluu,” “kutaa,” “qanoq ippit,” “qujanaq,” “aap,” and “naamik.”  We practiced some of our new skills when in town last night with noted documentary filmmaker, Patrick Morrell, and when meeting with the Inuit Circumpolar Council (ICC) this morning.

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View of Nuuk from the University. (Photo: A.Giese)

The roundtable gathering at ICC this morning was the highlight of our time here so far.  After meeting ICC International president Aqqaluk Lynge at Dartmouth last winter and again at IPY, we were all familiar with the basic aim and structure of the ICC: an organization that acts as a “permanent participant” in the Arctic Council and advocates for Inuit self-determination, human rights, health, education, language, political participation, and other Inuit interests.  The ICC bears the responsibility of implementing the UN Declaration of Indigenous Rights locally and firmly believes indigenous involvement essential to its efficacy.  The Inuit have reasserted their identity and human rights in recent decades as Greenland transitioned from colonial status to home rule and then to self-rule status in 2009.  Now, Greenland has autonomy in all areas except foreign affairs, defense, and financial policy.  (Note: this means that Greenland has complete ownership/control over its natural resources.)

ICC Greenland President, Carl Christian Olsen (Puju) spoke of the inception of the ICC, its integration into the Greenlandic government and UN, and its role around the circumpolar region in general.  Its range of interests is instantly apparent within the first 10 feet of the office, where I walked by the Arctic Pollution 2011 Report and the Inuit Diabetes Calendar.  Much of our conversation with Puju centered around the International Labor Organization (ILO) convention of 169, ratified by Denmark and Greenland in 1996, which required that nation states recognize indigenous identities, removed any mandatory assimilation practices, and permitted self identification.  A particularly illustrative example of the types of issues resolved by the UN ILO convention number 169 was that of individual land ownership (imposed during colonization) vs. common land use (Inuit practice); now, all of Greenland is public land.  Land use is a concern that extends beyond Greenland, too; because migratory patterns don’t conform to international boundaries, hunters often have to navigate different policies and regulations.

Another part of our conversation focused on the future, and Puju identified the navigability of the Arctic Ocean as a concern.  He also spoke of knowledge and resource sharing between the various geographical divisions of ICC.  Chukotka has been in need of aid following the collapse of the Soviet Union, and the ICC provided dentists, doctors, clothing, and housing.  Alaska can share its experience with resource (especial oil) development, Canada its progressive reputation for environmental management, and Greenland its political and social integration of Inuit peoples as well as its focus on human rights.  Despite the obvious and enormous challenges the ICC faces, it was reassuring and encouraging to hear optimism about the future.

It’s been an exciting, educational, and fun stay so far in Nuuk!  We have more exciting engagements coming up, like our public talks at Katuaq on Monday (see below), so stay tuned!

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One of my favorite parts of being in Greenland is seeing the fingerprint of glacial ice virtually everywhere. During the Last Glacial Period (~110,000 through 11,000 years ago), the Greenland Ice Sheet expanded to cover the entire landmass. Now, in the present Interglacial Period, the ice sheet has shrunk and exposed large areas of land that were formerly covered by ice. Accordingly, abundant glacial landforms are visible around the coastal areas of Greenland, and the IGERT students spent a day last week exploring them.

Glaciers are powerful agents of erosion. They can remove huge masses of material from the landscape through both scraping/scratching the underlying rock surfaces (a process called abrasion) and freezing to rock surfaces and pulling off large pieces (a process called plucking). Glacial erosion leads to distinctively-shaped bedrock forms that are often sculpted and smoothed.

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Glacially-sculpted bedrock forms above the harbor west of Kangerlussuaq, photo courtesy of Steph Gregory.

The material eroded by glaciers is carried through the ice as if on a conveyor belt, and is then deposited in a location in the down-ice direction from the material’s source. Most sediment deposited by glaciers is called glacial till; this material contains a mix of grain sizes (everything from clay to large boulders), is not sorted or layered, and often contains a mix of rock types that do not match the local bedrock. Glacial till is sometimes deposited in narrow ridges at the end and along the sides of a glacier. These ridges are called moraines and are useful for marking past positions of the glacier’s end, or terminus. Generally, younger moraines in Greenland, especially those deposited during a recent cold period called the Little Ice Age (~1450-1850 AD), are unvegetated and fresh. Conversely, older moraines in Greenland deposited during the ice recession after the Last Glacial Period are more weathered.

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The Little Ice Age moraine, composed of glacial till, rises high above the IGERT students at the ice margin near Kangerlussuaq.

To complete our study of glacial landforms and processes, we ventured up on the edge of the ice sheet at the end of the dirt road from Kangerlussuaq. Alas, this small area of the ice appears to be stagnant and is no longer flowing (although, fortunately, this also means that it is not crevassed and is therefore safe to walk on). The IGERT group spent a beautiful, sunny afternoon walking on the ice, examining the complex system of meltwater streams flowing on top of the ice sheet’s edge, and seeing sediment embedded in the ice that has been transported from Greenland’s interior.

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Glacial meltwater flows across the ice surface during summer months when temperatures are above freezing.

An important point to remember is that glacial features are visible in most northern areas of the United States too, including around Dartmouth! Next time you find yourself going for a walk in the woods or driving along the road in an area covered by ice during the Last Glacial Period, don’t forget to look for these fingerprints of lost ice. That piece of bedrock you’re standing on could preserve scratches, or striations, formed as an ice sheet several miles thick flowed over the exact area you’re currently standing!

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As someone who studies glaciers, I associate the Polar Regions with blue glacier ice and incomprehensibly large, flat, white expanses.  The “Arctic” does not conjure images of anything living, with the exception of the people who live on the rare spots of ice-free land, the mosquitoes that I’m always grateful to escape once on the ice itself, and the polar bears which, in my experience so far, have been only an abstract threat.  (Last year when Lee Corbett, Erich Osterberg, Eric Lutz, and I were in Thule, three bears wandered onto the Air Force Base, but operations quickly called a lockdown.  No one was allowed outside until the threat was “removed.”)

The Arctic, I learned last week, is teeming with wildlife, much of it barely visible (if that) to the human eye or covertly thriving in dense vegetation.  We spent two separate modules on organismal biology, the first in aquatic ecology under the tutelage of expert IGERT fellow Jess and the second in population ecology and herbivory with Matt Ayres.

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Jess teaching the cohort about Arctic aquatic ecology. (Photo: Giese)

Jess’ classroom was a lake adjacent to the ice sheet margin, and her zeal about both the location and the organisms we found engendered excitement among the biologists and non-biologists alike.  She talked to us about the aquatic food web and thermal lake stratification, describing that lakes typically have three layers: the epilimnion (surface layer), metalimnion (middle layer, AKA thermocline), and hypolimnion (bottom layer) that vary by density.  She then had us see what we could catch in nets along the lake edge.  We put on comically large waders; scooped up water, slime, and small plants; and dumped our findings into plastic buckets to see what was moving.

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Students examine their findings from the edge of the lake. (Photo: Ayres)

One of the most ubiquitous organisms we found was the diving beetle, Colymbetes dolabratus, the mosquito’s greatest enemy (I liked this thing instantly when I heard that).  We found it both in adult form and in larva stage, which I was surprised to learn was even larger.  Other notable findings were Chironomids, midges whose eyes and internal features we could see with a hand lens or macroscope once pipetted onto slides.  Some of them were even red because their blood was oxygenated.  We could see their guts filled with food, which they frequently passed.  Their circus-like, rapid flipping movement impressed those of us who had never seen such a thing before!  Apparently, these creatures, which looked a lot like worms to me, will turn into flies someday.

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Chironomid larvae. (Photo: Giese)

Other organisms we collected included ubiquitous mites, zooplankton-like Daphnia, fairy shrimp, and cyanobacteria (one of which closely resembled Gloeotrichia, a species Jess and lab her labmates study back in the Upper Valley!).  Watch for upcoming posts on the shrimp and cyanobacteria from Chelsea and Jess, respectively.

Our specimen collection didn’t end with the near-shore ecology; an inflatable boat took us out into the center of the lake to collect profiles of temperature, conductivity, pH, and dissolved oxygen.  Unfortunately, the high winds precluded us from keeping the boat in a single spot, and they led to so much mixing that the multiprobe readings reflected zero stratification.  Nevertheless, the boat trip was instructive for the non-aquatic ecologists in terms of providing a sense of typical measurements.  A net we dragged behind the boat did yield some interesting finds; Jess bottled up the zooplankton from the lake center to take back to Hanover and examine in more detail.

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Ali, Steph, and Jess lowering the plankton net from the Zodiak boat. (Photo: Ayres)

Water isn’t the only home of Arctic animals, and we spent part of the next day searching for organisms that live on land.  We had already established that our environment supported only 5 mammals—musk ox, caribou, Arctic fox, Arctic hare, and humans—most of which are vegetarians.  But it turns out that they’re not the only herbivores in the tundra!

Matt brought us out into a vegetated field and showed us to how to find the smaller herbivores, which make up in cumulative biomass what they lack in individual size.  We were looking specifically for caterpillars, which had a huge population boom last year.  We heard stories from IGERT cohort II about how these creatures were all over their tents and how it was difficult to walk without stepping on them!  We hadn’t seen any caterpillars yet, but the abundance of overgrazed (i.e. dead) Betula nana was evidence that cohort II hadn’t been exaggerating.

We marched through the vegetation, swinging wildly at the leaves with our nets.


Lee catching bugs in the tundra. (Photo: Corbett)

We then examined our collection…and here began the fun part.  Before the bugs scampered or flew away, we had to catch them by sucking them into a sample bottle (a process called aspiration).  Because there’s a screen between the mouth tube and the sample bottle, it is impossible to have a critter end up in your mouth, but it still took some of us a little while to get used to.


Matt demonstrating the aspiration technique. (Photo: Giese)

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Lee, Steph, and Chelsea collected these insects.  Note the caterpillars in the lower left, stuck together with spider web. (Photo: Corbett)

We found surprisingly few caterpillars; Jess and I found a rough total of five in eight net sweeps.  Instead of caterpillars, spiders appeared to comprise the majority of small creatures in the tundra vegetation.  But this begged a question: since spiders are not eating the plants, what are they eating?  We came up with a few hypotheses, the most promising of which seemed to be that they were eating each other (I didn’t know spiders could be cannibals).  Isotope analysis back in Hanover would tell us for sure; because organisms preferentially excrete the lighter form of nitrogen (N-14), heavier nitrogen (N-15) builds up in tissues.  This means that the primary producers (plant-eaters) have relatively low levels of heavy nitrogen while animals farther up the food chain have increasing concentrations of it.  We’d expect all organisms at the same “trophic level” to have about the same concentrations, but if the spiders are eating each other, there will be greater variation than normally expected (since they’re eating each other as well as below their trophic level).  Little did I know that isotopes could tell us about spider diets as well as past climates and glacial extents!

After the insect and spider lesson, we ventured over to the ice sheet to explore two different parts of its margin.  But I returned to the ice with a much greater appreciation of the myriad of dynamic systems at work on the world’s largest island.

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