Climate Change at the Arctic's Edge

Expedition Briefing


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The Research

At the Arctic’s edge we can measure the evidence of climate change: shrinking areas of polar sea ice, retreating glaciers, and less extensive winter snowpack that also melts earlier (ACIA, 2004; IPCC, 2013; SWIPA, 2017). Biological evidence of warming is also mounting. For example, more trees have begun to grow at the northern treeline and different plant communities are appearing. Northern ecosystems are changing (Bonan et al., 1992, Chapin III et al., 2005, Harsch et al., 2009). Over the next few decades, scientists expect to observe the greatest effects of global warming at high latitudes. Global warming estimates go as high as a 6°C (10.8°F) increase in average air temperature by 2100 relative to the 1986–2005 mean (Diffenbaugh and Field, 2013), and are predicted to increase by as much as 10°C (18.0°F) in the Arctic (IPCC, 2014). Churchill, on Canada’s Hudson Bay, has warmed approximately 2°C (3.6°F) since record keeping began in the 1880s, though about 75% of that warming occurred since 1980.

On a global scale, the position of the circumboreal treeline is determined by temperature. However, local treeline positions are modified by frost damage, winter desiccation, and a host of other factors. It is necessary to assess the effects of site- specific variables, which could confound the influence of increasing temperatures.

Permafrost—ground that remains below freezing for more than a year—holds crucial clues to what global warming might entail. It underlies 24% of the surface of the earth, including vast areas of Russia, Canada, China, and Alaska. An estimated 50% of the world’s terrestrial carbon is locked up in permafrost (Tarnocai et al., 2009).

Research Aims

At the Churchill Northern Studies Centre (CNSC), our main research goal has been to establish an environmental monitoring program to collect baseline quantitative data on climate-related changes in northern ecosystems. Along with the long-term monitoring of environmental conditions, we also conduct experiments to more closely examine the processes occurring in these subarctic conditions. You help obtain large numbers of samples over a short time period and are vital to the success of the monitoring and experimental programs. People depend on the health and integrity of the natural world for food, income, and other resources, so collecting such data is vitally important. Locally, many of the residents of Churchill, our nearest neighbors, depend on ecotourism for their livelihood, and our research can inform better policy for preserving the ecosystem that supports them in addition to its global resonance.

This project focuses on three of the global warming related changes scientists have observed: thawing permafrost, shift of the treeline to the north, and wetland dynamics. We have established 11 long-term environmental monitoring sites along a line extending from the boreal forest into the arctic tundra to measure a set of key ecosystem components. These include components of the environment like snow conditions, ground temperature, depth of thawing, soil carbon as well the biological components of the ecosystem like trees, shrubs, frogs and fish. At our monitoring sites, automated microclimate stations— which monitor the state of permafrost and active layer—operate year round. We also monitor permafrost and the active layer as part of our fieldwork, through repeated probing and coring. We sample and analyze the snowpack in mid-winter. And in the lab, we analyze needle desiccation to determine the amount of damage to the cuticles on the needles during the harsh subarctic winter.

Monitoring the treeline by recording the presence of seedlings, saplings, and trees is another big component of this project. We focus on the treeline because minor changes in the environment can have big ecological impacts on it. For example, warmer growing seasons can lead to more viable tree seeds and higher germination success, which means that more trees grow further into the tundra—thus changing where the treeline lies. Within the forest-tundra zone, buds and leaves are exposed to colder temperatures and higher amounts of wind-blown snow abrasion. Wind-blown snow can thin or remove the waxy cuticle covering needles resulting in excessive water loss and needle mortality, which can reduce the plants’ photosynthetic capability during the following growing season. Furthermore, insufficient maturation of the cuticle in the summer can lead to excessive winter moisture loss. Depending on the intensity, duration, and variability, cold and windy conditions impair vital functions and can set the distributional limits of plant species, though conflicting results from other studies warrant further research.

The research also focuses on isolated wetlands—bodies of water that have highly variable biological and hydrological characteristics and make up about 40% of the surface area in landscape of the Hudson Bay Lowlands (HBL). Because of the temporary character of some of these wetlands, the aquatic organisms differ from those of larger and deeper permanent bodies of water. One important difference is that they usually lack predators such as larger fish and invertebrates, which are a significant predatory component in aquatic systems. As a result, many organisms have developed specific life histories to take advantage of the characteristics of the wetland, and as the climate changes, so too does the character, chemistry and species habitat within these wetlands.

How You Will Help

You’ll get the chance to help with both field and lab research. The amount of time you will spend at each will vary with the season; however, you should expect to spend about 50% of your time at the research sites and the remainder in the lab. You will help set up and monitor equipment and collect data on features of the snowpack, permafrost, and soil; the occurrence of vascular plants, lichens, and mosses; wetland water quality; amphibian tadpole metamorphosis; fish behavior and annual growth rings of trees.


For this research you will focus on the physical and biological characteristics of the environment. You’ll study 1) growth, sexual reproduction, and survivorship of treeline trees and 2) winter injury of evergreen needles. In addition to ongoing monitoring of natural seedling establishment and survival in the field, seeding experiments will be conducted as part of the Global Treeline Range Expansion Experiment (G- TREE). G-TREE is a globally distributed collaborative project aimed at testing the generality of mechanisms driving boundaries of tree distribution at the treeline ( Soil sampling, permafrost coring, thaw depth measurements, and vegetation sampling could be on the task list of a given team. Equipment for air and ground temperature measurements will be maintained, and cover values for shrubs and trees will be estimated. On fall teams, the depth of thaw will be probed and the standard soil characteristics, including organic matter, moisture content, and pH may be determined. The teams could also be involved in sampling the total above-ground biomass from plots within each site.


Summer and fall teams will study the impact of stand-replacing fires near treeline. Seedlings were planted within the burned areas during 2000 to assess recruitment and survival in disturbed and undisturbed habitats. You will help monitor establishment and recruitment of seedlings by assessing plant species cover and measuring seedling height and number of branches.


These teams will focus on the diverse wetland environments that make up 40% of the land cover in this region. The importance of hydroperiod in the wetlands to species compositions during the summer months has been highlighted by the continued long-term monitoring. The recent inclusion of experimental approaches to the wetland component of the research program has allowed for examination of processes that will assist in explaining the natural variation occurring on the landscape. You’ll don waist-high neoprene waders to collect data on species and water quality from natural shallow tundra ponds and wetlands as well as participate in our mesocosm experiments in outdoor stock tanks. The project will provide the neoprene waders and gloves for the duration of the project.


Assignments for the winter team will include snowpack descriptions, snow sampling, and lab processing of samples. Outdoor activities will depend on light and weather conditions; winter can be extremely physically demanding. CNSC can rent gear to participants, including parkas, pants, mitts, and boots, but participants will be required to bring their own liner gloves and headgear. Trips in the qamutiks (sleds pulled behind snowmobiles) can be rough, cold, and uncomfortable but the winter landscape will leave you breathless.


Life in the Field

You’ll get plenty of learning opportunities on this expedition: you may hear talks on local permafrost landforms, the ecology of polar bears, whales, species migration, wetland diversity, the significance of the project to the community, and climate change monitoring in general.

Depending on your team’s particular tasks, you’ll also hear practical talks on snow pit measurements, plant species identification, wetland structure, sampling techniques, and monitoring and census techniques. You will also learn about the concepts behind the sampling methodology, and the use of various kinds of equipment.

While you’ll spend most of your time on research tasks, you’ll always have the chance to ask questions, enjoy the scenery, and take in the majesty of the northern treeline. In this pristine environment, there are endless opportunities to view rarely seen wildlife and plants. CNSC was established in 1976 to facilitate research, and you will have the opportunity to interact with many other scientists conducting research in the area. It is not uncommon for participants to sit at a cafeteria table with scientists and have a conversation directly with them about their studies. These researchers are also likely to give informal lectures during which in-depth discussions can carry on for hours. You will be in the midst of an intellectual environment unique to a center like CNSC.

Weather and research needs can lead to changes in the daily schedule. We appreciate your cooperation and understanding.

  • Day 1: Introduction and orientation, getting off to a gradual start to enable participants to recover from travel. A meeting will be conducted to outline the objectives and methods of the team and guidelines for safety, and to provide a preliminary schedule. After this, the team will normally take a brief walk to become familiar with the site and test outdoor gear.
  • Day 2: Demonstrations of equipment and training. If this is completed in the morning, the team will practice field methods in the afternoon.
  • Days 3–10: Each day will begin with a briefing to outline the day’s activities. At least half of each day will be spent at the research sites collecting data, while the remainder of the day will be used for sample processing and data entry. Depending on the tasks, we might make an evening trip to catch the sunset or take other excursions. There will normally be an evening briefing to review the day’s activities followed by a lecture or lab or data entry work. On the last evening we’ll have a wrap-up seminar with an overview of the data, comments, recommendations, and discussion about the significance of your contributions to the overall research picture.
  • Day 11: Travel day
Recreational Time

Usually, on the fifth or sixth day of the expedition, the team will have a recreational day (the exact day will depend on weather and research activities). The summer teams will have the opportunity to visit the town of Churchill, where you can participate in a number of organized activities, including whale watching (approx. $120-190CAD, depending on the boat and number of people); a tour of Fort Prince of Wales, a national historic site (approx. $115CAD, including the boat trip across the Churchill River); river kayaking ($190CAD); browsing through the Eskimo Museum ($10CAD donation); a regional natural history tour (approx. $110CAD); or simply souvenir shopping. The winter teams will also have the opportunity to visit the town of Churchill and participate in an authentic dogsledding adventure tour (approx. $100 CAD). All activities are seasonal and weather dependent and staff at the CNSC will help to coordinate these activities with the local operators.


Accommodations and Food

The Churchill region is polar bear country, and significant safety issues exist whenever we are out of doors. The CNSC is 23 kilometers (14 miles) east of the town of Churchill, and consequently, participants must be accompanied by a CNSC staff member or the scientist, who will carry bear deterrents, before being allowed to go out of doors during free time. When you arrive on-site you will sign the Churchill Northern Studies Centre’s Polar Bear Information Acknowledgement Form. CNSC is a non-smoking facility.


* Please note that not every expedition has couples’ or single's accommodations available. Please call or email Earthwatch to check for availability prior to reserving your space(s) on the team.

You’ll stay in dormitory rooms that house up to four people in bunk beds. Normally, rooms will be single gender. Depending on the bookings, it might be possible to arrange for single accommodations—contact your Earthwatch representative about this option. Single/couple rooms cannot be guaranteed.

* Earthwatch will honor each person’s assertion of gender identity, respectfully and without judgement. For both teen and adult teams, where logistics dictate single-sex accommodations or other facilities, participant placements will be made in accordance with the gender identity the participant specified on their Earthwatch Participant form and/or preferences indicated in discussions with Earthwatch.


Teams 8 and 9 Only: The optional activity of building igloos requires cutting, lifting, and placing 20- to 30- kilogram (45- to 65-pound) blocks of snow that should not be dropped, and at 70 x 50 x 15 centimeters (28 x 20 x 6 inches), each block can be awkward to maneuver. This task requires a lot of energy. Fortunately, there are usually enough people participating to share the heavier tasks. Sleeping bags and pads can be rented from the Centre if you want to stay overnight in your newly constructed snow shelter subject to environmental conditions.


The CNSC water is trucked to the facility, so we practice water- saving measures, including composting toilets and encouraging all visitors to take short showers. There is running water throughout the facility, which includes flush toilets and individual shower rooms. Laundry is available for a fee of $6 CAD per load (washing detergent is included; coin operated).


The CNSC has reliable electricity (outlet types A or B, 120 volts, 60 hertz). You should bring along any necessary converters and adapters.


There is a cell phone booster located in the atrium of the CNSC for calls but it is best not to rely on there being cell coverage throughout the building or at field sites. There is wireless internet throughout CNSC available at no additional charge and Wi-Fi calling is a possibility with some cell phones. There will be a computer available for participants to use in free time but it is recommended to bring a computer or tablet for personal use if possible.


All research sites are within 40 minutes of the CNSC. Transport is by van or SUV, except in winter, when participants are transported in qamutiks (sleds pulled behind snowmobiles).


The kitchen is run by accredited cooks who prepare all the meals. Food is served cafeteria style, and all users of CNSC share the dining area. Participants will assist with after meal cleanup. Meals are varied and usually include a choice of salads, desserts, and a vegetarian dish. We also have fresh bread and evening snacks.

The following are examples of foods you may find in the field. Variety depends on availability. We appreciate your flexibility.

  • Breakfast: Eggs, bacon, toast, porridge, pancakes, French toast, sausages, fresh/dried fruit, yogurt, muffins, cold cereals, toast
  • Lunch: Soup, sandwiches, macaroni and cheese, grilled cheese sandwiches, burgers, French fries, fruit
  • Dinner: Meatloaf, spaghetti, roast beef, turkey, lasagna, fish, potatoes, pork chops, pizza, chicken, salads, Jell-O, cake, pie, fresh fruit, cooked vegetables, stew
  • Snacks: Leftovers, fruit, cookies, cereal, popcorn
  • Beverages: Coffee, tea, hot chocolate, water
  • Water: All water is drinkable. Cold, fresh water is available for free in the cafeteria at all times.

Please alert Earthwatch to any special dietary requirements (e.g., diabetes, lactose intolerance, nut or other food allergies, vegetarian or vegan diets) as soon as possible, and note them in the space provided on your participant forms.

Accommodating special diets is not guaranteed. Vegetarian, lactose intolerance, gluten intolerance, and other allergies can generally be accommodated with prior notification.

Project Conditions

The information that follows is as accurate as possible, but please keep in mind that conditions may change.

The majority of the sites are gravel, peat over sand, or peat over permafrost. In general, the area ranges from flat to hummocky. The wetlands have standing surface water for the most part, and some have mucky bottom sediments. On average, temperatures at Churchill over the summer period range from -5 to 28°C (23°F to 82°F). There is very little humidity, except during periods of fog when the wind comes off the Bay, and rainfall during the summer is usually around 2.5 inches (6 cm) per month. Spring begins in June with the end of snowfall and melt, while late August is the beginning of autumn and brings cooler temperatures. The average temperature, however, is often misleading since it can feel like autumn in the morning and the height of summer in the afternoon following a shift in the wind.

The winter (when Team 8 & 9 will be in the field) is long and dominated by extremely cold arctic air masses, often with strong winds. In mid-winter, temperature becomes irrelevant (it’s usually just -40°C/-40°F) and wind chill values are used. In February the wind chill often exceeds -45°C (-50°F) and exposed skin will freeze in seconds. The upside is that at this time of year there are no insect pests, and the long nights provide an amazing opportunity to view the northern lights.


For weather and region-specific information, please visit and search for your project location.

Essential Eligibility Requirements

All participants must be able to:

  • Take an active role in your own safety by recognizing and avoiding hazards if and when they arise (including, but not limited to, those described in Earthwatch materials and safety briefings). Comply with project staff instructions and recommended safety measures at all times.
  • Be able to effectively communicate to the staff if you are experiencing distress or need assistance.
  • Be comfortable being surrounded by a language and/or culture that is different from your own.
  • Be able to get along with a variety of people from different backgrounds and ages, often in close proximity, for the duration of your team.
  • Follow verbal and/or visual instructions independently or with the assistance of a companion.
  • Wear all protective equipment recommended or required by industry standards; especially important for the winter team. If you bring gear that the staff feels is inappropriate, you may have to rent gear at your own expense. Please read the section for winter team in the Expedition Packing Checklist.
  • Enjoy being outdoors all day in all types of weather, in the potential presence of wild animals and insects.
  • Tolerate temperatures as high as 28°C (82°F) and as low as -55°C (-67°F) in winter.
  • Carry personal daily supplies, such as lunch, water, and some small field equipment, of up to nine kilograms (20 pounds).
  • Repeatedly get low enough to undertake ground-level activities such as soil sampling, permafrost coring, frost probing, vegetation sampling, and fish and amphibian trapping, up to 12 hours per day.
  • Traverse varying terrain from level hard surfaces to undulating, hummocky ground. Total time hiking is up to four hours per day.
  • Promptly alert project staff about any injuries or discomfort (bruising, difficulty breathing, etc.) as soon as it occurs.
  • Winter Team Only: Travel in a seated, upright position within a qamutik sled during transit, which can sometimes be bumpy. This can be uncomfortable for individuals with back problems.
  • Winter Team Only: Maintain a high enough calorie intake to keep up with increased energy demands of working in frigid temperatures and deep snow.

Health and Safety


Field staff members carry handheld radios to communicate with CNSC, from where someone would call the hospital for guidance in an emergency. There is always a vehicle available in the field, and a number of first aid kits are maintained at CNSC. Anyone with a medical emergency will be evacuated directly to the hospital in Churchill. If the situation is severe, a helicopter can be used to transport the injured person. In the event of a dangerous encounter with a polar bear, the animal will be deterred using standard procedures, and the team will leave the area and report the incident to CNSC.

Earthwatch has a 24-hour, 7-day-a-week emergency hotline number. Someone is always on call to respond to messages that come into our live answering service.


Please be sure your routine immunizations are up-to-date (for example: diphtheria, pertussis, tetanus, polio, measles, mumps, rubella and varicella) and you have the appropriate vaccinations for your travel destination. Medical decisions are the responsibility of each volunteer and his or her doctor. Visit the Center for Disease Control and Prevention or the World Health Organization for guidance on immunizations.

If traveling from countries or region where yellow fever is endemic, you must have a certificate of vaccination.

Project Risks and Precautions


The road is gravel and its condition varies depending on the weather. In winter (Team 8 & 9), whiteouts and icy roads make driving conditions more difficult. The winter team will be transported into the field on qamutiks (sleds pulled behind snowmobiles). There are no safety belts on these sleds. The snow is quite hard, and the qamutiks offer no cushioning. You may wish to bring your own padding for travel while in the qamutiks (see the section for winter team in the Expedition Packing Checklist). All drivers hold licenses required by the Canadian government and vehicles meet provincial safety standards with the addition of shortwave radios to talk to the base


Hiking along the trails to the research sites varies from unstable ground with tall shrubs, to open hard ground. Trail sections can also be very wet with deep holes (at times the depth exceeds the height of participants’ rubber boots). Teams working in wetlands will be wading in standing water that may be up to 75 cm in depth using neoprene waders. Waders and rubber boots are provided on site.


All participants will be hiking in the field, and there is risk of strains, sprains, and breaks due to falls. Trails are well marked and the participants will be traveling as a group, but the footing can be slippery, especially with frost or light snow or rain. You must have rubber boots due to sections of wetlands at several sites and the tall shrubs that can restrict movement at some sites.


The Churchill region has a large concentration of polar bears. Consequently, the teams will have to be near a vehicle equipped with a radio and armed with suitable deterrents at all times. Project staff will have a number of polar bear deterrents, ranging from noisemakers to firearms. CNSC has thorough safety standards in place for the use and management of firearms. For safety considerations, it will not be possible to avoid being in the presence of firearms. Participants will not handle or use the firearms. The Earthwatch scientist and other field staff (NOT participants) will carry deterrents.


Mosquito and blackfly populations are very dense in July and August. They are present in June and September as well, but less intense. At this time, there is no evidence of West Nile virus in the Churchill region, although it is present in southern Manitoba. Take precautions to prevent mosquito bites by using insect repellent and wearing long-sleeved shirts and bug jackets or head nets while in the field. Black flies bite and inject an anticoagulant and are generally very irritating. If you suspect you might have an allergic reaction to their bites, bring an antihistamine.


During fall and winter (Teams 7, 8 & 9), there are risks of hypothermia, frostnip, frostbite, extreme chapping and cracking of lips and hands, and other cold-related injuries, as well as cold-caused damage to personal gear. The risk of cold-related injury is increased in those with heart and lung disease and any other conditions that reduce or impair circulation to the skin and extremities. Certain medications can exacerbate risks of cold-related injury.

In all seasons, the sun can be quite intense. Even on an overcast day, you are at risk of sunburn; bring plenty of good-quality sun block and lip sun and wind block. Also, the environment is dry year round, so drink plenty of water to avoid dehydration.

Distance from Medical Care

The nearest hospital is 23 kilometers (15 miles) away from the project site, and it may take up to an hour to arrange transport and reach the hospital. If you have a chronic condition which could require immediate medical care (e.g., heart conditions, kidney problems, severe asthma, etc.), or if you are pregnant, please discuss your participation on this expedition with your physician.


Traveler’s diarrhea affects many international travelers. Please see the U.S. Centers for Disease Control and Prevention ( or the World Health Organization ( websites for more information on this condition and how to avoid it.

A note on vaccinations and treatment:

West Nile Virus: West Nile is a mosquito-transmitted virus. Several cases of West Nile virus are reported each year from southern Manitoba; however, as of the printing of this expedition briefing, no cases have been reported in northern Manitoba, where the Churchill teams take place.

Travel Planning


Churchill Airport or train station, Manitoba, Canada

Additional information will be provided by Earthwatch to meet your team. Please do not book travel arrangements such as flights until you have received additional information from Earthwatch.


Earthwatch strongly recommends that travelers investigate their destination prior to departure. Familiarity with the destination’s entry/exit requirements, visas, local laws, and customs can go a long way to ensuring smooth travel. The U.S. Department of State's Traveler’s Checklist and Destination Guides are helpful resources. For LGBTI travelers, the U.S. Department of State's LGBTI Travelers page contains many useful tips and links.


Entry visa requirements differ by country of origin, layover, and destination, and do change unexpectedly. For this reason, please confirm your visa requirements at the time of booking and, again, 90 days prior to travel. Please apply early for your visa (we recommend starting 6 months prior to the start of your expedition). Refunds will not be made for volunteers cancelling due to not obtaining their visa in time to meet the team at the rendezvous. You can find up to date visa requirements at the following website:

If a visa is required, participants should apply for a TOURIST visa. Please note that obtaining a visa can take weeks or even months. We strongly recommend using a visa agency, which can both expedite and simplify the process.

Generally, passports must be valid for at least six months from the date of entry and a return ticket is required.


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