Trees in the Tundra

Earthwatch scientists search for evidence of climate change in one of the most extraordinary places on the planet.

By Alix Morris


Welcome to Churchill, Manitoba.

At the southern edge of the Arctic, in Canada’s Hudson Bay lowlands, lies Churchill, Manitoba—a small town that sits at the convergence of tundra, forest, freshwater, and marine ecosystems. Churchill is perhaps best known for the roughly 1,000 polar bears that migrate to the region each year, earning it the nickname of “polar bear capital of the world.” These massive predators gather as they wait for the sea ice to freeze along the shores of the Hudson Bay before they begin their hunt for seals.

In the summer months, thousands of migrating beluga whales enter the Bay, just after breeding season. They stay in the river estuaries and along the coast throughout the summer to feed on capelin and give birth to their young before migrating back out into Hudson Strait and the North Atlantic. Churchill is also a bird lover’s paradise—more than 250 species of birds nest or fly through during their annual migrations.

For humans, however, the small town of Churchill is not for the faint of heart. In the winter months, the wind chill can drop to -50 degrees Fahrenheit. The cold is so severe that it threatens to seal eyelashes shut and freeze exposed skin. It can turn water to ice before it’s poured.

Why would anyone live in such a harsh, unforgiving climate? For Earthwatch researchers LeeAnn Fishback and Steve Mamet, the question is—why not?


Polar Bears in Churchill

Polar bears gather in Churchill as they wait for sea ice to freeze.



Arctic Fever

Earthwatch Scientists Steve Mamet and LeeAnn FishbackEarthwatch Scientist Dr. LeeAnn Fishback grew up on a dairy farm in Southern Ontario. Unlike most children her age who longed for the summer months, LeeAnn looked forward to the winter. Some of her earliest memories as a child involved racing after her Newfoundland dog as he bounded through the snow, carving a path for her to follow. Her parents, who had more time to spend with their children during the winter months, taught her to skate and toboggan. She quickly grew to love winter and the cold.

Years later, LeeAnn, who is now the Scientific Coordinator at the Churchill Northern Studies Centre, looked for opportunities to travel even further north—to experience the true Arctic. When the opportunity arose to spend a summer in the High Arctic of Canada, she jumped at it. She had no idea just how significant an experience it would be.

During her second year of fieldwork, in 1993, LeeAnn experienced one of the warmest years in the High Arctic. She and her research team set up their camp on the glacier where they would spend the summer studying snow and ice melt.

On a glacier, there’s typically an “accumulation zone” at higher elevations where the snow is building up and doesn’t melt. The warmer “ablation zone” is at lower elevations—this is where melting occurs. LeeAnn and her team had set up their camp in the accumulation zone, expecting that they would be able to live in the snow for the whole summer. But by early July it became apparent that the entire glacier was turning into an ablation zone. There was melting everywhere, and nothing they could do to prevent it.

"We moved our camp off the glacier and continued to work on that study looking at glacier melt and ablation over the course of the summer," said LeeAnn. "But that's when I really started to think a lot more about climate change in the Arctic and how relevant it would be to the rest of my life."


I think that was when climate change really hit home for me— when I was living on a piece of ice that was melting away and it shouldn't have been."

— LeeAnn Fishback





An Expert Warning

In 1989, Earthwatch Chief Scientist Dr. Bill Moomaw attended the first meeting of the United Nations Intergovernmental Panel on Climate Change (IPCC)—the international group responsible for assessing the science related to climate change. The meeting took place at the State Department in Washington, D.C. During the year that followed, several hundred scientists, economists, political scientists, and other experts convened to draft the first IPCC report. Their conclusion, tentative at the time: the climate might be changing, and humans could be the ones causing it. Bill became one of the lead authors for five succeeding IPCC reports, each of which provided stronger and more definitive evidence that the climate is changing and is a result of human influence.

For years, the media presented a “he said, she said” approach to the issue—presenting climate change as a theory or a topic up for debate. Deniers were given the same weight as those who marshaled evidence. Today, however, the majority of media reports focus on the effects of climate change—no longer giving the same credit to those who question its existence.

For the past few months, newspapers have been featuring numerous reports on climate change, and for good reason. 2014 was the warmest year on record. What’s more, the IPCC recently issued their starkest warning yet: the human influence on the climate is clear. Our emissions of carbon dioxide and other greenhouse gases have raised atmospheric concentrations to their highest levels by far than at any time in the past 800,000 years. Thousands of observations find that the atmosphere, land, and oceans have warmed. The amount of snow and ice has diminished, and the sea level has risen.

Based on today’s assessment, the question of whether humans have influenced the climate has been answered. The challenge now is to better understand these changes so we can mitigate their effects as responsibly as possible.

Back in the small town of Churchill, scientists and volunteers have been collecting some of the most significant evidence of climate change. Their data serve as a powerful indication of what’s to come.



What Happens in the Arctic Doesn't Stay in the Arctic

The Arctic and subarctic regions are critical to understanding the effects of climate change. But why are these regions so important? In part, it’s because changes in climate are amplified at the poles, and these regions are warming faster than elsewhere on the planet.

Churchill is located at the Arctic treeline, and is extremely sensitive to small environmental changes that have a huge impact on ecosystems. Warming temperatures have led to shrinking areas of polar sea ice, freshwater wetlands that are drying up, and less extensive winter snowpack that melts earlier.

One area of research scientists have been studying is the effect of warming temperatures on permafrost—a frozen layer of earth that starts within a meter of the surface. Permafrost, which covers 24% of the landmass in the northern hemisphere, is made up of dead plant matter that hold virtually all of the carbon stored by individual plants during their lives. Some of these deposits are more than 40,000 years old. If the permafrost begins to thaw, it could release carbon in the form of carbon dioxide and methane—two of the most dangerous greenhouse gases.

In Churchill, LeeAnn and Steve have focused their research on the biological evidence of warming, specifically wetland dynamics and a shifting treeline.

Shallow wetlands make up approximately 40% of the tundra landscape in the region. Warming temperatures lead to more evaporation, which can alter these ecosystems that are susceptible to drying over the course of the summer. This has the potential to adversely affect some of the species that depend on the wetlands for reproduction or food.

Warming also carries with it the possibility of an advancing treeline. Moving north towards the poles, the temperature drops. The point at which it becomes too cold for trees to grow is referred to as the treeline. With warming temperatures, trees advance into the tundra. Tree movement changes the entire ecosystem—everything from insects to small mammals to predators—the lemmings, the arctic fox, the snowy owl.

An advancing treeline could also lead to additional warming (dark trees absorb more sunlight) and release of additional greenhouse gases (more trees means more water vapor in the air). In Churchill today, islands of trees are emerging in a sea of tundra—islands that researchers believe may serve as a nucleus for further treeline expansion in the future.

In this subarctic climate, LeeAnn and Steve are working with Earthwatch volunteers and students to study these important research areas. Evidence collected in Churchill provides scientists with a first indication of climate change, and offers critical clues as to what the future might have in store for the environment. It’s a canary in the coal mine—a first warning of a large-scale challenge.

Earthwatch volunteers measuring snow pack (Credit: Elaine Spence)

Volunteers measuring snow pack (Credit: Elaine Spence).

A volunteer collecting data on the Arctic's soil

A volunteer collecting data on the Arctic's soil (Credit: Chris Parkinson)



In the Arctic, change is happening more rapidly, so it’s easier to follow and to monitor. The temperature change is two, three and, in a few places, four times faster than the earth as a whole. The Arctic is covered with ice and snow—in many places year round, but that is changing. As ice and snow melt, a surface that reflects 90% of sunlight is replaced with a surface that absorbs 90% of sunlight…Since the Arctic is shifting most dramatically from a reflecting body to an absorbing body, it’s heating up faster than the rest of the earth. And that’s changing the dynamic of weather over the whole earth.

— Bill Moomaw, Earthwatch Chief Scientist 



A Little History

Back in 1999, Dr. Peter Scott, then the Scientific Coordinator at the Churchill Northern Studies Centre, reached out to staff at Earthwatch to see whether they would be interested in partnering with the Centre to study the impact of climate change. Earthwatch agreed—launching one of the organization’s first studies directly focused on climate change.   

Peter then contacted Dr. Peter Kershaw, a professor at the University of Alberta, and asked if he’d be willing to help lead the Earthwatch expeditions. Peter went on to lead Earthwatch teams for more than a decade. Earthwatch volunteers, and citizen science more broadly, contributed a great deal of value to the climate change research.


Citizen scientists know a hell of a lot more than you do on many things. In some cases, they’re senior people, or they’re really young people and eager to learn.

— Pete Kershaw


When Pete retired in 2013, he handed over the project reins to his former PhD student—Steve Mamet, who is now a Postdoctoral Fellow at the University of Saskatchewan, and the current Scientific Coordinator at the Centre who had replaced Peter Scott in 2002, LeeAnn Fishback. Both LeeAnn and Steve had been working with Earthwatch teams during Peter’s tenure and were therefore well suited to lead the research.

Today, climate change is one of Earthwatch’s key research focus areas. But it doesn’t end there. A changed climate affects everything Earthwatch studies, says Bill Moomaw. Take ocean health, for example. By changing the atmosphere in a fundamental way, carbon dioxide is dissolving into the ocean, making it more acidic. More acidic oceans can dissolve coral reefs and the shells of animals such as clams or oysters.

Climate change isn’t a vague concept, says Bill. These fundamental changes that take place affect biodiversity, ocean health, terrestrial ecosystems, agriculture, human wellbeing, water, and water distribution—environmental challenges that lie at the core of Earthwatch’s mission.



The "So What?" Factor

LeeAnn and Steve would love to say that their research directly influences policy decisions. But it’s not quite as simple as that. Climate change is a political and economic minefield, and policy decisions are based on more than just science. 


We're actually out there, we're on the ground, we're observing any changes that are occurring and we're collecting data on them...The models are very important but the field data is there to make sure we're on the right track.

— Steve Mamet


While the research from the Churchill project often feeds into policy assessments such as the IPCC reports, it doesn’t always result in direct or immediate policy or action. The timeline from data analysis to actual policy change can take many years. Science has been documenting a changing climate for 30 years.

So what drives these scientists in the meantime?

Steve believes field science is critical to understanding the effects of climate change. A lot of what we know about climate change is based on sophisticated computer models—models that make assumptions where data don’t exist. For Steve, field data are critical.

For LeeAnn, one incredibly important contribution they can make is training Earthwatch volunteers. As researchers and educators, LeeAnn and Steve aim to reach out to as many people as they can—to give them the opportunity to ask questions, to better understand climate change. These volunteers can then return home and better inform their own communities. Through education and awareness, she believes they can have a tangible impact.

Volunteers not only support their data collection, they provide meaning and purpose for their work. In Churchill, volunteers have enabled scientists to paint one of the clearest pictures of climate change in the Arctic, so we can better understand the changes that will eventually take place in our own backyard. It’s evidence of the power of connecting citizens to science.



It's not just about participating in science or having a really great vacation in Churchill. It's about leaving our project with a meaningful experience and sense of place. They not only see how important the Arctic is but they have a better understanding of what climate change really is.

— LeeAnn Fishback



Why Do Scientists Do It? Careers and Caterpillars

Dr. Steve Mamet didn’t always want to be a scientist. When he was young, his career goals ranged from wanting to do special effects for movies to being a fireman. But he was constantly pulled back to science by his innate love of nature.

Steve’s parents like to tell the story of a time when young Steve became intensely curious about a caterpillar he found in the yard. For an entire afternoon, he followed the caterpillar around and mapped its trail with sand. All over the yard was a long, meandering line of sand where the caterpillar had traveled during the day.

“At the time, I think my parents thought that counseling would have been a solid option,” said Steve. “But it turns out the answer was scientific endeavors.”

For Steve, who is infatuated with murder mysteries, Churchill offers the perfect landscape for crime-solving.


Earthwatch volunteers digging in the snow (Credit: Shawn Brown)

Volunteers digging in the snow (Credit: Shawn Brown).


I always want to find out 'whodunit.' With observational science in the field, you make some initial observations and then you formulate a hypothesis—and then see if the evidence you're collecting in the field supports that hypothesis. You're after those satisfying Eureka moments.

— Steve Mamet



A Citizen Scientist in Action

Mark Stratton, a reporter who covered this Earthwatch expedition recently for National Geographic, found his experience unforgettable. Here's what he had to say: "Never turn a man away if he comes to your door naked, as there will always be a polar bear behind him."

This local saying isn’t suggesting climate has ameliorated in Canada’s frozen north to an extent that naturism is in vogue. It’s more a reflection of Churchill’s wild frontier spirit that makes it such a special backdrop to experience Earthwatch’s Climate Change at the Arctic Edge expedition.

I joined my fellow Earthwatchers in the Hudson Bay tundra at Churchill’s research facility. Yet while I arrived with an outline understanding of the issues surrounding climate change I wasn’t exactly cognizant of the science driving global warming.

Steve Mamet was instantly reassuring. “We don’t want you to just believe in climate change we also want you to understand it,” he said.

As a non-practicing citizen scientist, I soon learned climate change research requires bundles of hard work and dedication to produce rigorous data.

Thus our days in the field were long and passed as quickly as the cook’s crispy bacon was devoured at breakfast. On the tundra by 8am, tasks ranged from vegetation sampling to ascertain whether coniferous seedlings were marching northwards as temperatures rise to probing permafrost depths. We remained in the field after lunch before returning to the field station for labwork, typically seed analysis, which continued after a hearty dinner.

If data collection occasionally felt inconsequential during times when cold Arctic winds were strafing us on the tundra, our science team of Steve and LeeAnn Fishback warmed our spirits by making us feel appreciated.

Steve provided a humorous laidback presence leading us out onto the tundra daily. “Anybody bend one of my permafrost borers and I’ll bore your brains out,” was among his repertoire of offbeat humor. This was balanced by heartfelt flattery. “These are long days guys, I really appreciate the effort you’re putting in for the greater good,” he said more than once.

Meanwhile the research center's director, LeeAnn, delivered several big picture evening lectures putting our efforts into context. I had no idea before arriving of the harmful effects of sulphur hexafluoride or the influence of Milankovitch Cycles on climate. But now I’d learned something to dazzle my friends at dinner parties during those inevitable pseudo-intellectual debates.

But it was also my fellow volunteers who helped turn this into such an unforgettable experience as I gained a healthy respect and bonding with them. Take Christy from the Philippines, who had only ever once left the tropics. She bore the sometimes freezing rain and winds with remarkable good-natured stoicism. What a star.


What did I get out of this experience? A love of the tundra's stark beauty, great camaraderie, and a better informed perspective to take away and argue more effectively this complex issue.

— Mark Stratton


My fellow volunteers made life inside the research facility convivial and fun. And hey, yes, even the most mundane tasks can be a blast. During long evenings counting microscopic seeds using tweezers the group’s chatter, Steve’s slightly dubious music choices, and the odd glass of vino, kept us cheery.

What did I get out of this experience? A love of the tundra’s stark beauty, great camaraderie, and a better informed perspective to take away and argue more effectively this complex issue.

As Steve noted before we left, almost certainly paraphrasing Bob Dylan. “These times they are a changing … but they sure are variable.”



Get Involved with Earthwatch

Help Steve and LeeAnn to conserve and study this magnificent landscape by signing up for the expedition Climate Change at the Arctic's Edge expedition and help us to protect this iconic species.

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