To watch the full interview, please visit CTV News.

To listen to the full interview, please click here.

As sea ice declines and shipping and industry increases in the Arctic, University of Manitoba researchers will study whether naturally-existing bacteria in ocean ice and water can degrade petroleum as a response to potential oil spills.

The research team, GENICE II, received $6.7 million in federal funding from Innovation, Science and Economic Development. Experiments will be conducted at the new Churchill Marine Observatory.

“In that facility there are two big tanks, where we’re going to grow ice and… add oil to one and not to the other and look at the effects on the natural community when you add oil — look at what microbes might be present that are naturally degrading the oil,” said Eric Collins, who along with Gary Stern, heads the research team.

The team will use genomic tools — the study of genes — to examine the microbes…The team will partner with Inuit and other Arctic communities.

“The communities are extremely worried about (increased ship traffic and industry), because if there was ever a large scale spill it would pretty much decimate the ecosystem within and around the area,” Stern said.

Baker Lake, Arviat, Chesterfield and Rankin Inlet will be part of a monitoring program, with the team training people to collect sea ice and water samples.

Read the full Free Press story here.

More than 1,500 students attended the unique Arctic and climate science workshop with experts in physical and chemical oceanography, sea ice optics, marine mammals, remote sensing, contaminants, and oil spills.

Scientists from the Centre for Earth Observation Science (CEOS) in the Clayton H. Riddell Faculty of Environment, Earth, and Resources at the University of Manitoba gave seminars, demonstrations, and answered students’ questions live through Zoom.

This digital edition of Arctic Science Day was even more accessible than years prior, through a format that allowed more students to participate. The new virtual experience was viewed by students throughout the entire province, including Frontier School Division which hosts Manitoba’s northernmost young learners.

This year’s event didn’t include live ice auger demonstrations, but students had a mixed schedule of information seminars and hands-on learning activities. They asked insightful questions throughout each session, displaying their interest and literacy in science topics. Teachers approved as well.

“The activities provided for Arctic Science Day were great,” says Diane Nickel, French Immersion Teacher 7e année, École Communautaire Leila North. “My students were engaged and loved the connections that were made while having fun.”

Physical oceanography lessons came from faculty research professors Karen Alley and Juliana Marini Marson, as well as postdoctoral researchers Erica Rosenblum and Laura Gillard.

Students learned about sea ice and optics from postdoc Aura Diaz and PhD candidate Lisa Matthes, including lessons on instruments and technology used in the field, and principles like sunlight reflection, scattering, absorption and transmission, with functions like the albedo effect where more light is absorbed by dark colours than bright colours, resulting in rising temperatures from polar ice melt.

Aura Diaz showing how liquid enters an ice core using a colour dye

PhD candidate Tonya Burgers taught aspects of chemical oceanography like how much dissolved carbon is in the Arctic Ocean, and how much carbon in the Arctic Ocean is absorbing from the atmosphere. Burgers also taught concepts like temperature effects on air volume using household materials.

“What happens when CO2 dissolves in water, it reacts with the water and forms carbonic acid,” Burgers tells students, explaining how the process impacts water quality indicators like pH levels.

Students took a break from chemistry for whale watching as they learned about marine mammals and remote sensing methods with researchers Maddie Harasyn, Elizabeth Worden, and Emma Ausen.

Harasyn showed how she pilots drones to study sea ice properties like surface elevation, or to find areas of land slumping, or permafrost melt where indicators of climate change can be found. Harasyn also showed students the Sea ice Environmental Research Facility (SERF) on UM campus, where researchers study different ways of monitoring sea ice with satellites, and what happens to microplastics in sea ice. Students also learned how researchers like Harasyn train machine learning algorithms to identify marine mammals in drone footage.

Ausen described the processes of researching marine mammals, from data collection to analyzing key indicators like abundance and distribution. Worden told students about the impacts of climate change on communities and traditions.

Worden describes “a whole cocktail of climate change” taking place in the Arctic, including “strong storms, earlier ice break-up, changing the timing of migrations, rivers changing their paths, so access to the ocean getting harder, coastal erosion, unpredictable weather conditions,” she lists. “And then there’s also social change which is more complicated and more personalized.”

Postdoc Diana Saltymakova led a session on oil spills with PhD candidates Durell Desmond and Kasia Polcwiartek where students learned about the impacts of oil in the ocean through interactive demonstrations that students followed along with on their own.

Kasia Polcwiartek leading students through activity teaching oil spreading with household items

CEOS Technician Debbie Armstrong wrapped up the day’s programming teaching students the difference between a contaminant (a substance in greater concentration than normal in an environment) and a pollutant (a contaminant that results in adverse health effects within ecosystems). General types of water pollutants include nutrients, decomposed algal blooms, trace metals, pesticides, oil, microplastics, zebra mussels, acid rain, and more.

Students finished Arctic Science Day with the starter tool kit for Arctic science research, having learned, participated, asked questions, and received answers from scientists conducting world-leading research into important environment and climate topics.

In 1966, US Army scientists drilled down through nearly 1,390 meters of ice in northwest Greenland, and pulled up a more than three meter tube of dirt from the bottom. The frozen sediment was moved to a freezer in Copenhagen in 1994 and forgotten. In 2017, the sample was again moved to a new freezer and the frozen sediments were accidentally rediscovered.

In 2019, two samples of sediments were studied by a team of scientists from Denmark and the US, and the team couldn’t believe what they saw: twigs and leaves instead of just sand and rock. That suggested that the ice was gone in the recent geologic past—and that a vegetated landscape, perhaps a boreal forest, stood where a mile-deep ice sheet stands today.

Over the last year, an international team of scientists – led by Dorthe Dahl-Jensen at the University of Manitoba and University of Copenhagen, Andrew Christ and Paul Bierman at University of Vermont, and Jean-Louis Tison at Université Libre de Bruxelles – studied the one-of-a-kind fossil plants and sediment from the bottom of Greenland. Their results show that most, or all, of Greenland has been ice-covered the last million years and ice-free for a period before this time.

“Ice sheets freeze and preserve material in a very pristine way,” says Dorthe Dahl-Jensen, Canada Excellent Research Chair at University of Manitoba.

“But it is a miracle to directly discover delicate plant structures perfectly preserved. They’re fossils, but they look like they died yesterday. It’s a time capsule of what used to live on Greenland that we wouldn’t be able to find anywhere else.”

The discovery helps confirm a new and troubling understanding that the Greenland ice has melted off entirely during recent warm periods in Earth’s history—periods like the one we are now contributing to with human-caused climate change.

Understanding the Greenland Ice Sheet in the past is critical for predicting how it will respond to climate warming in the future and how quickly it will melt. Since some seven meters of sea-level rise is tied up in Greenland’s ice, every coastal city in the world is at risk. The new study provides the strongest evidence yet that Greenland is more fragile to climate change than previously understood—and at grave risk of irreversibly melting off.

“This is a very urgent problem,” says Dahl-Jensen. “Sea level change will impact a significant part of the global population within the next 50 years.”

The new research was published March 15 in the Proceedings of the National Academy of Sciences. (PNAS).

Beneath the Ice

The material for the new PNAS study came from Camp Century, a Cold War military base dug inside the ice sheet far above the Arctic Circle in the 1960s. The hidden purpose of the camp was a super-secret effort, called Project Iceworm, to hide 600 nuclear missiles under the ice close to the Soviet Union. As cover, the Army presented the camp as a polar science station.

The military mission failed, but the science team did complete important research, including drilling a 1,390 meter-deep ice core. The Camp Century scientists were focused on the ice itself, being the first deep ice core ever drilled. The stable water isotopes measured by professor Willi Dansgaard was the first climate record from ice cores and became an important part of the burgeoning effort at the time to understand the deep history of Earth’s ice ages. They apparently took less interest in a bit of dirt gathered from beneath the ice core. Then, in a truly cinematic set of strange plot twists, the ice core was moved from an Army freezer to the University at Buffalo in the 1970s, to another freezer in Copenhagen, Denmark, in the 1990s, where it languished for decades—until it surfaced when the cores were being moved to a new freezer.

For much of the Pleistocene—the icy period covering the last 2.6 million years—portions of the ice on Greenland persisted even during warmer spells called “interglacials.” But most of this general story has been pieced together from indirect evidence in mud and rock that washed off the island and was gathered by offshore ocean drilling. The extent of Greenland’s ice sheet and what kinds of ecosystems existed there before the last interglacial warm period—that ended about 120,000 years ago—have been hotly debated and poorly understood.

The new study makes clear that the deep ice at Camp Century—some 120 km inland from the coast and only 1300 km from the North Pole—entirely melted at some time within the last million years and was covered with vegetation, including moss and perhaps trees. The new research lines up with data from two other ice cores from the center of Greenland, collected in 1990s. Sediment from the bottom of these cores also indicate that the ice sheet was gone for some time in the recent geologic past. The combination of these cores from the center of Greenland with the new insight from Camp Century in the far northwest give researchers an unprecedented view of the shifting fate of the entire Greenland ice sheet

The team of scientists used a series of advanced analytical techniques—none of which were available to researchers fifty years ago—to probe the sediment, fossils, and the waxy coating of leaves found at the bottom of the Camp Century ice core. For example, they measured ratios of rare forms—isotopes—of both aluminum and the element beryllium that form in quartz only when the ground is exposed to the sky and can be hit by cosmic rays. These ratios gave the scientists a window onto how long rocks at the surface were exposed vs. buried under layers of ice. This analysis gives the scientists a kind of clock for measuring what was happening on Greenland in the past. Another test used rare forms of oxygen, found in the ice within the sediment, to reveal that precipitation must have fallen at much lower elevations than the height of the current ice sheet, “demonstrating ice sheet absence,” the team writes. Combining these techniques with studies of luminescence that estimate the amount of time since sediment was exposed to light, radiocarbon-dating of bits of wood in the ice, and analysis of how layers of ice and debris were arranged—allowed the team to be clear that most, if not all, of Greenland melted at least once during the past million years—making Greenland green with moss and lichen, and perhaps with spruce and fir trees.

In a 1960s movie about Camp Century created by the Army, the narrator notes that “more than ninety percent of Greenland is permanently frozen under a polar ice cap.” This new study makes clear that it’s not as permanent as we once thought. “Our study shows that Greenland is sensitive to natural climate warming, but significant warming is needed to melt the full Greenland ice sheet, a state we will reach in the future warming climate,” says Dahl-Jensen.

Media Contact:

Sam Swanson
Communications and Outreach Coordinator
Centre for Earth Observation Science
University of Manitoba
Phone: +1 (204) 590-8591
E-Mail: samuel.swanson@umanitoba.ca

What is your full name, and your position?

My full name is Juliana Marini Marson, and I am an assistant professor at CEOS.

What attracted you to the University of Manitoba?

Well, I’d been looking for a tenure-track position for a while, and when this particular position opened up, I was very excited because it was exactly the type of research I wanted to do. So, I thought maybe now the stars are aligned and this will work out for me. And so it did. My husband and I moved from Brazil to Canada five years ago, and we have loved living here, no matter in which city. And once we came to Winnipeg and got to know a bit of the city, we already liked it. So, all ended up very well for me.

What would be your superpower?

I think I’d like to be as fast as Flash, just so I could visit my family in Brazil for a weekend and come back really quickly. That would be useful.

What’s your favourite place in the world?

That’s an interesting question. I’ve visited several beautiful places, but I would say my favourite place is my home, especially my bedroom. I love that moment at the end of the day when I can finally sit down on my bed and gather some thoughts and read a book or watch something to relax.

Who do you follow on social media?

Mostly my family and friends, just to keep them updated on our life in Canada. I also follow some funny pages like “Pet Portraits by Hercule” or Nathan W. Pyle – super recommend if you are not familiar with them, and some science-, animal-, parenting-related pages. But honestly, nowadays I barely have time to check out social media.

What would people be surprised to learn about you?

I don’t know if this is surprising or just embarrassing. But I have a pretty hard time spelling out loud. If I have to spell something, I have to write it down first. It’s not that I don’t know the correct spelling of things, but my brain just stops working when I have to say the individual letters out loud. I don’t know if I am a tad dyslexic, but this certainly puts me in some awkward situation sometimes.

What is your main research focus?

My main research focus is studying the polar oceans – the interactions between ocean and ice and climate. I’m especially interested in how warming and increasing freshwater, especially coming from melting glaciers, ice caps, and ice sheets, in the oceans. They are affecting physical processes like ocean circulation and other biogeochemical processes, such as primary productivity and carbon sequestration. And the main tools that I use to study the polar oceans are numerical models. I’m also quite interested in icebergs – their drift patterns, their physical and ecological impacts on the ocean, how these will change in the future, and how they will affect socioeconomic activities that are affected by them.

Is there a story behind what attracted you to your research area?

I decided to be an oceanographer when I was 12. That’s when I took an intensive, three-day marine biology course. I just fell in love with it and decided I wanted to study anything related to the ocean.

What is the most difficult thing you’ve ever done?

Ah, I think becoming a mom. Not necessarily labour, although that’s pretty difficult, but becoming a parent. I am an anxiety-driven person who likes their routine and having things under control. When a child comes into your life, all that is out of the window. Also, all the high-level math courses I’ve done were just insanely difficult because they were taught by geniuses. That’s why one of my life’s missions, to explain hard things in simple ways so everyone can understand them.

What is one experience that changed your life?

I don’t think there was this one thing that made everything change. I think every major change in my life came from a process, usually involving the search for who I am and what is my purpose in life. This long-term type of reflection really makes you focus on what is important and changes the way you see everything around you.

What is your greatest indulgence?

Ice cream? Yeah, that’s one thing that I just can’t live without.

What is your favorite movie or book?

I have several favourites, but one book that comes to mind is I Know Why the Caged Bird Sings, from Maya Angelou. It’s one of her autobiographies, and it’s just beautifully written. It shows what this woman had to overcome during her life and how she became an incredible person nevertheless. It’s truly inspiring. I’ve even named my daughter after Maya Angelou, and I hope she is strong as her namesake.

How do you like to relax?

Binge-watching TV shows, playing video games or reading when I have time to myself. Otherwise, playing with my daughter and petting my dog are things that help a lot to de-stress.

What are you reading or watching right now?

I’m reading a book called Erebus [by Michael Palin] which recounts the ship’s voyages and its final demise in the Northwest Passage. It’s quite interesting getting to know the people whose names were used to name straits, channels, and sounds in the Canadian Arctic.

What is your greatest fear?

Maybe one fear is dying without doing something meaningful for other people. The other one is regarding the safety of my daughter. That’s a normal maternal fear, I guess.

If you’re singing karaoke, what would your song be?

Ah, probably a nursery rhyme since those are high up on my playlist right now! Five little ducks?

What is your most treasured possession?

My computer – it was the first one I built and it has everything I wanted in terms of configuration, so I can use it both for work and for gaming.

What personal trait are you most grateful for having?

I’m patient. I’m very patient. I’m really grateful for that, especially now with the pandemic when we have to spend all day at home with family.

What three people would join you for your dream dinner party?

Oh, wow. I would say my three grandparents who have passed away. I barely knew my grandfather on my father’s side when he passed. So that would be a great opportunity to know him better. But I grew up with both my grandparents on my mother’s side, and I just miss them so much.

What would you say is your best quality?  And what would you say is your worst?

My best quality is that I’m very organized with my work stuff. All my notes are very neat, and I usually have all my ducks in a row work-wise. My worst quality is that I’m not super organized with my personal stuff. I leave things in places they don’t belong – I function well in a kind of organized mess, if you will. But my husband is a neat-freak, so he gets a bit cranky with me sometimes.

If you did not take this career path, what would you have chosen?

I’d have chosen music if not oceanography by the time I finished high school. I played the clarinet for a long, long time and I loved it very much. But if you asked me what other path I’d choose today, I’d say computer science or astrophysics.

In November 2020, NASA and the University of Manitoba highlighted a few compelling features around the Thomsen River estuary on Banks Island, including lines of sea ice tracing the shoreline and the braided pattern of the river. But there’s so much more to explore across this remote lowland tundra and river valley. 

January 27th, 2021 by Kathryn Hansen/NASA Earth Observatory, and Robie Macdonald/University of Manitoba/Dept. of Fisheries and Oceans

Robie Macdonald, a scientist at the Centre for Earth Observation Science at the University of Manitoba, shared some photos that he shot while doing fieldwork in the region between 2014 and 2016. The purpose of that project was to collect geochemical measurements from small rivers across the Canadian Arctic Archipelago. 

“I really do love working in these places,” Macdonald said. “Once the aircraft has landed, one is bathed in a tremendous silence broken only by waves breaking on shingle. Then you have this incredible tundra spreading out toward the hills that define the river floodplain.” 

Here are ten of Macdonald’s favorite photographs.  

1. Ponds and Oxbows

“Numerous ponds of all sizes populate the drainage basins of Banks Island, and you can see several clusters of them in the satellite image (top), especially along the small river to the west of the Thomsen. This photograph provides a closer look at one such pond cluster. In the image, you can also see textbook oxbows, which have become the setting for more ponds.”

2. Permafrost Polygons

“During breeding season, it seems like almost every pond on Banks Island has its own population of snow geese (visible in this photo). You can also see old permafrost polygons that are now submerged within the pond. Polygons are widespread features of the permafrost in soil-rich locations and are produced over time by freeze-thaw cycles of the surface active layer. Permafrost thaw is widely impacting these regions, leading to feedbacks in the carbon system (CO2, CH4).”

3. Vibrant Vegetation

“Perhaps the most surprising characteristic of the valley bottoms in this ‘Arctic desert’ is the vibrant color of the vegetation: yellows, greens, and reds mark a dense ground cover that can be seen on the satellite image as areas with a yellowish-brownish cast.” Robie Macdonald/University of Manitoba

4. Sediment Ripples

“As a result of the strong sediment supply, the large embayment at the Thomsen River mouth has been practically filled with sediment. The shallow water reveals itself in the satellite image by the lighter-greenish tone compared to water out in the channel north of Banks Island. More evidence of the ample sediment supply can be seen in beautiful displays of sand/silt ripples in the lower river between the islands. In the satellite image (top), the ripples are almost visible as grey zones between the islands before the river enters the open bay.”

5. Ice Shoves

“When walking on these islands near the river mouth, you can see evidence of bank erosion and ‘ice shoves.’ These are produced when wind forces newly formed ice to ride up over the river bank and gouge out the top layer of the silty material that makes up these islands. Unfortunately, ice shoves are too small to show on the satellite image.”

6. Vulnerable Permafrost

“Global warming and the extensive loss of sea-ice cover in late summer have helped accelerate coastal erosion and permafrost slumping. This image shows a section of coastline just to the east of the Thomsen River mouth that consists of a lot of frozen ice. This sort of permafrost is especially vulnerable to the changing temperature regime.”

7. Erosion and Slumping

“Thaw slumps are also a sign of the permafrost warming. These can be seen just barely in the satellite image as small dark regions along cliff faces–both facing the ocean and within the river drainage basins. Erosion and slumping expose ancient organic carbon to the air and the hydrosphere, thus providing an extensive positive feedback to climate warming.” Photo by Robie Macdonald/University of Manitoba

8. Bergy Bits

“Lines of bergy bits has collected along a thin shore margin at the point where the sea bottom rapidly deepens below ice keel depths, likely at approximately 2-4 meters. Although the grounded ice bits are continually melting, they are resupplied by more ice chunks shed from the permanent pack out in the channel. Two turbid plumes supplied by a river to the west of the Thomsen easily pass through the necklace of ice.”

9. Sampling Amid an Icy Barrier

“When we were sampling the water in this region, we found this ice barrier to be a bit more of a problem to navigate in our small inflatable boats, but ice along the shore did make it simple to sample sea ice. This image shows Greg Lehn preparing to launch our boat.”

10. A Suitable Landing Spot

Sampling in the Thomson River itself was somewhat simpler, once we had found a suitable place to land the plane. This image shows Greg Lehn scoping out the shore of the Thomsen River near its mouth.”

See the article as originally published by NASA Earth Observatory here.

Recognizing the significance of this collection, Dr. Shelley Sweeney, recently retired Head of the University of Manitoba Libraries, Archives & Special Collections, collaborated with Gabriel Gély, his wife Dorothy Myhal Gély, and private collectors Kathyrn Knowles and Susan Howe to facilitate its acquisition by the University of Manitoba.

Following the end of World War II, Gély’s love affair with the Canadian Arctic was sparked by a chance viewing of an Inuit artifact display that was mounted in the windows of the Libraire Sainte Beuve, in Paris. The young ex-soldier and resistance fighter decided to use his savings to travel to Canada in 1952.

By 1953 he found employment as a cook with the Department of Transport (DOT) Canada at several weather stations located at Clyde River (Kanngiqtugaapik), Baffin Island, Ennadai Lake and at Sachs Harbour (Ikaahuk) on Banks Island.

While at Ennadai Lake, he attempted to alleviate the plight of starving families by feeding them from the supplies located in the downstairs area of his workplace. In recognition of his generosity, Gély was given the name Taraami, translated loosely as “Downstairs,” a reference to the location of the DOT supplies.

From 1956 until the late 1980s, Gély held major positions with the federal government as an administrator and arts and crafts advisor for the Arctic region. He also was a self-employed  contractor with the Federal and Territorial governments.

Valued for their subject-matter and artistic appeal, Gély sold some of his photographs to publications such as The Beaver magazine (now Canada’s History magazine). In addition, he raised funds and received a grant for the “Return to Ennadai Lake” project, which documented a visit by Arviat families to their Ennadai Lake homeland. [According to the CBC, “approximately 80 Ahiarmiut families were packed on airplanes and taken from their home near Ennadai Lake”; the Canadian government issued an long-awaited apology in early 2019.]

Gély’s large collection of images span the years 1954 to 1987 and consists of photographs primarily of people and scenes in the following communities from various periods of time: 

• Arctic Bay (Ikpiarjuk)
• Arviat, Baker Lake (Qamani)
• Clyde River (Kangiqtugaapik)
• Ennadai Lake
• Gjoa Haven (Uqsuqtuuq)
• Grise Ford (Ausuittuq)
• Hall Beach (Sanirajak)
• Lake Harbour (Kimmirut)
• Pangnirtung
• Pond Inlet (Mittimatalik)
• Rankin Inlet (Kangiqliniq)
• Repulse Bay Repulse Bay (Naujaat)
• Sachs Harbour (Ikaahuk)
• Spence Bay (Talurjuaq)

In total, there are 671 slides, approximately 2125 negatives, 125 proofs and 597 photographs in black and white and colour.

The Archives is presently closed due to COVID restrictions. The Gabriel Gély collection is currently not available online, but the Archives is developing a digitization plan for our return to campus. Please contact the archives for further information on this collection.

Photo references:

• Gabriel Gély photographed in his  studio.
  Courtesy of Gabriel Gély and Dorothy Myhal Gély©.
• Gabriel Gély, Mrs. Annie Sewoee (Alikaswa), Mrs. Atasluk and Mr. Yaha, Arviat, 1967.
  Gabriel Gély fonds, A2018-025, Box 1, File 3.
• Gabriel Gély posed with his camera and hunting guide, Noah. Clyde River (Kanngiqtugaapik), Baffin Island, 1954.
  Gabriel Gély fonds, A2018-025, Box 1, File 12. 
• Pangullaq (right) with wife Ulujak, Ennadai Lake, 1954. Photographed by Gabriel Gély.
  Gabriel Gély fonds, A2018-025, Box 1, File 2.  
• Gabriel Gély used his photographs as references for the subjects of his paintings. Ikalujuak carving at Clyde River, 1980. Photographed by Gabriel Gély.
  Gabriel Gély fonds, A2018-025, Box 1, File 9. 
• Gély’s oil painting of Ikalujuak, 1984.
  Image courtesy of Gabriel Gély.
• Ekalujuak’s son (left) with Kabloonaq, Clyde River (Kanngiqtugaapik), Baffin Island, 1953 or 1954. Photographed by Gabriel Gély.
  Gabriel Gély fonds, A2018-025, Box 1, File 14. 
• Atasluk with unidentified child, Arviat, 1977. Photographed by Gabriel Gély.
  Gabriel Gély fonds, A2018-025, Box 1, File 10.

Arctic sea ice has been in steep decline over the last two decades. Meanwhile, tundra shrub abundance has been increasing in many regions of the Arctic. A new study published in the Proceedings of the National Academy of Sciences of the United States of America reveals that declining Arctic sea ice extent has been associated with increasing shrub growth in some regions of the Arctic and decreasing growth in other, generally drier, regions.

An international team from eight countries led by Dr. Agata Buchwal from Adam Mickiewicz University in Poznan, Poland gathered 23 existing shrub-ring chronologies and investigated their relationship to changes in sea ice extent, air temperature and precipitation.

One of the study’s lead co-authors is Dr. Julienne Stroeve, Senior Canada-150 Research Chair in Climate Forcing of Sea Ice at the Centre for Earth Observation Science at the University of Manitoba.

“Previous studies have suggested an increase in vegetation from sea ice loss as a result of enhanced warming, but this study shows that shrub growth responses are varied and the reasons seems to be a result of dry vs. wet conditions,” says Stroeve.

The project’s data set included birches and willows from Alaska, the Canadian Arctic, Greenland, Svalbard and Siberia.

“Our synthesis represents a major collaborative effort to disentangle one of the most complex issues in climate change research: heterogeneity of tundra shrub dynamics across the Arctic” says Buchwal.

While Arctic tundra greening and browning have received increasing attention over the past decade, one comparatively under-studied area is the ultimate role of sea ice dynamics and decline as drivers of terrestrial vegetation change. Sea ice decline is emerging as a powerful driver of warming and associated precipitation changes across the Arctic, and tundra shrubs are recognized as climatically sensitive proxies of Arctic environmental change. However, sea ice – shrub interactions had not been studied at the Pan-Arctic scale. “The comprehensive assessment reported in our synthesis not only addresses that knowledge gap, but also, more importantly, documents contrasting influences of declining sea ice on summer climate and shrub growth at the biome scale”, says Buchwal.

While the majority of shrubs take advantage of warming induced by sea ice decline and increase their growth, there is a remarkable group of shrubs that have progressively decreased their growth during the period of sea ice decline. What drives these divergent shrub growth responses to declining sea ice extent? Buchwal and team have shown that regional changes in sea ice extent are highly coupled with changes in local temperature and moisture availability. Specifically, sites with shrubs that grew less with the declining sea ice extent were characterized by increasingly drier conditions that hampered their growth.

Why we should care about the tundra shrubs? The implications of increasing heterogeneity in shrub growth responses to sea ice-induced changes in climate might be widespread, with local to global consequences, including carbon uptake potential and albedo effects. While tundra areas dominated by increasers have the potential to take up and store more carbon from the atmosphere, areas dominated by decreasers might be areas of increasing carbon loss to the atmosphere.

“Tundra shrubs will not announce the effects of climate change in the Arctic. Instead they patiently record their responses to change in their growth rings. And it is our task to learn from their records,” says Buchwal. 

This new addition to our understanding of tundra shrubs can potentially improve the models used to forecast climate change. “I hope that this research can go into new parameterizations for climate models to better predict tundra responses,” says Stroeve.

Media Contact:

Sam Swanson
Communications and Outreach Coordinator
Centre for Earth Observation Science
University of Manitoba
Phone: +1 (204) 590-8591
E-Mail: samuel.swanson@umanitoba.ca

Phytoplankton are free-floating microscopic organisms, most of which are single-celled algae. Like terrestrial plants, they use photosynthesis to turn light into chemical energy by consuming carbon dioxide (CO2) and nutrients in the water. Phytoplankton are the basis of the marine food web and play a vital role in the carbon cycle by absorbing CO2 from the atmosphere.

Until roughly a decade ago, most scientists assumed that phytoplankton remained in a sort of stasis throughout the winter and spring until sea ice break-up. Now there is a growing body of evidence that suggests under-ice blooms (UIBs) of phytoplankton can occur in low-light environments below sea ice.

“Up to about a decade ago, most Arctic phytoplankton research focused on open water and ice-edge conditions as there was a long-running assumption that not enough light reached under the sea ice cover to allow for a bloom to occur,” explained CJ Mundy, co-author of the study and Associate Professor at the University of Manitoba’s Centre for Earth Observation Science (CEOS).

“However, this assumption was flawed in that under-ice phytoplankton blooms can and do occur during the melt period, and sometimes before melt if the ice and snow cover are thin enough.”

Associate Professor CJ Mundy onboard the R/V William Kennedy

The prior belief was that phytoplankton blooming in low-light environments below sea ice was uncommon.

“There was a long-standing assumption that what was happening under the sea ice in the water column was almost ‘on pause’ during the polar night and before seasonal sea ice retreat, which is apparently not the case,” said lead author Mathieu Ardyna, a postdoctoral fellow at Stanford University.

The revelation means that phytoplankton production in some regions of the Arctic Ocean may be an order of magnitude greater than originally predicted. That’s important for climate modellers who want to know how much atmospheric carbon is being absorbed by these algae.

Few places on Earth are transforming as rapidly as the Arctic due to climate change. Over the past 30 years, the Arctic has warmed at roughly twice the rate as the global average. One of the most visible signs of that change has been in the decline of the sea ice that floats on the ocean surface, with this year’s ice cover shrinking to the second lowest extent on record.

“It was fascinating to discover that so many regions of the Arctic Ocean provide a favorable habitat for these little algae to flourish when the sea ice cover is still present in late spring. It shows once more how vibrant the Arctic ecosystem is,” said Lisa Matthes, a PhD candidate at CEOS and co-author of the study. “But it also highlights that environmental changes induced by global warming affect all levels of the marine food web, from phytoplankton to polar bears,” she added.

It’s no surprise that the thinning ice cover has enabled phytoplankton, which require light for photosynthesis, to flourish. What was surprising to the researchers is that the phenomenon of UIBs occurred well before climate change affected Arctic sea ice.

“Digging up research that occurred from the ’50s and prior demonstrates that blooms, albeit not very large, were occurring under thick ice in the central Arctic,” he explained. “I think this fact surprised many of us, as models had suggested this was not the case.”

The historical observations included a pair of studies during the International Geophysical Year, a global campaign that ushered in the modern scientific era. The authors noted, “The end result of this work was nothing less than an incredible first glimpse of UIBs occurring in the central Arctic.”

The paper goes on to describe the variability among UIB events across the Arctic Ocean in terms of occurrence, magnitude, and even the type of organisms present. Some of those findings are based on scientific programs and expeditions dedicated to studying UIBs specifically. In many cases, observations relied on autonomous floats, robotic gliders and even remotely operated vehicles that can swim under the sea ice.

Ardyna said further observations to feed new computer models will be key to more accurately predict how the Arctic carbon cycle will change in the future.