Grass, Shrub, Grass… Tree! Measuring Regrowth in a Burned Forest

A black spruce sapling growing among grass in an area of taiga forest that burned in 2015. Credits: NASA/Maria-José Viñas


“Oh, and here’s a black spruce!” exclaimed Charlotte Weinstein, an assistant research scientist at Michigan Tech Research Institute (MTRI), while pointing at a delicate sapling barely the height of a thumb that was almost hidden among the tall grass.

Weinstein and her colleague Shannon Rose, a research fellow at University of Massachusetts-Amherst (UM-A), were painstakingly counting and cataloguing each plant growing in a one-by-one-meter square plot set up in a taiga forest in a remote corner of Canada’s Northwest Territories. The forest burned in 2015, and the wildfire left behind an austere landscape of blackened thin trunks sticking out from the ground, interspersed with patches of exposed limestone rock that had previously been covered by a thick mat of organic soil that burned during the fire.

Four years after the event, vegetation is growing again. But how different will it be from the original taiga forest? Will the new shrubs and trees and the reforming organic soil layer be able to store a similar amount of carbon? Will the changes in plant composition and soil moisture also affect the animal species dependent on the forest?

Charlotte Weinstein (right) and Shannon Rose catalogue all growing in a one-by-one-meter square plot. Credits: NASA/Maria-José Viñas

To answer those questions and more, groups of researchers from all over the United States and Canada are flocking to the Northwest Territories in summer 2019 to carry field work under the umbrella of NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE), a comprehensive field campaign that probes the resilience of Arctic and boreal  ecosystems and societies to environmental change – including wildfires.

Weinstein and Rose worked together with Mike Battaglia (MTRI) and Paul Siqueira (UM-A), who took measurements of soil moisture and active layer depth (the top layer of soil that thaws during the summer and freezes in autumn) while the women counted plants. The researchers had all been doing field work for days when a small team of NASA communicators, including this writer, visited them in the field on Aug. 17; they still had about a dozen field sites to explore in the upcoming days. After sampling the burned area, the group moved on to a nearby swath of intact forest – in there, under the canopy of the intact trees, the carbon-rich soil was incredibly squishy and would sink under one’s steps, enveloping my hiking boots in bright green moss.

The active layer and soil moisture measurements were repeated in the unburned forest, but this time the researchers were also gauging plant biomass. Weinstein and Rose started measuring the diameter and height of all trees within a 10-by-10-meter square, while Battaglia dug a pit and extracted a large cube of dark soil to measure and take samples of the organic layers. Because the soil is frozen most of the year in the Arctic and boreal regions, the organic matter within doesn’t decompose. As a result, soils in those parts of the world often sequester more carbon than the trees and shrubs growing on them.

Mike Battaglia holds up a block of carbon-rich soil extracted from an unburned forest near Kakisa, Northwest Territories, Canada. Credits: NASA/Maria-José Viñas

After their field campaign, the team’s measurements of plant composition, biomass, soil moisture and active layer will become part of ABoVE’s  wealth of publicly-shared data.

“Our end game is to incorporate all field and remote sensing measurements into computer models to understand the long-term change of the land,” Battaglia said.

Students Traverse Land, Air, and Water in Canada with NASA’s ABoVE

Joanne Speakman helps scientists map wetlands near the city of Yellowknife in the Northwest Territories, Canada. Credits: Paul Siqueira


My name is Joanne Speakman and I’m from the Northwest Territories (NT) in Canada. I’m indigenous to the Sahtu Region and grew up in Délįne, a beautiful town of about 500 on Great Bear Lake. Now I live in Yellowknife, NT, and study environmental sciences at the University of Alberta. I was a summer student this year with the Sahtu Secretariat Incorporated (SSI), an awesome organization in the NT that acts as a bridge between land corporations in the Sahtu. My supervisor, Cindy Gilday, helped organize a once-in-a-lifetime opportunity for me and a fellow student from Délįne, Mandy Bayha, to fly with NASA. It was a dream come true.

One of NASA’s projects is called the Arctic-Boreal Vulnerability Experiment (ABoVE), which is studying climate change in the northern parts of the world. People from the circumpolar regions have seen firsthand how drastically the environment has changed in such a short period of time, especially those of us who still spend time out on the land. Weather has become more unpredictable and ice has been melting sooner, making it more difficult to fish in the spring. Climate change has also contributed to the decline in caribou, crucial to Dene people in the north, both spiritually and for sustenance.

Studies like ABoVE can help explain why and how these changes are happening. Along with traditional knowledge gained from northern communities, information collected by ABoVE can go a long way in helping to protect the environment for our people and future generations.

Wednesday, August 22, 2018:

Joanne Speakman sits behind the pilots during takeoff. Credits: Mandy Bayha

It was exciting to meet the ABoVE project manager, Peter Griffith, and the flight crew because it’s amazing what they do, and to fly with them was an incredible opportunity to learn from one another. Although we were from different parts of the world, at the end of the day we are all people who care about taking care of the environment. We flew on a Gulfstream III jet to survey the land using remote sensing technology. We flew from Yellowknife to Kakisa, Fort Providence, Fort Simpson and then back to Yellowknife.

During the flight, crew ran the remote sensing system and they explained to us how it works. It got complicated pretty quickly, but from what I understood, a remote sensor is attached to the bottom of the plane and sends radio waves to the ground and bounce back, providing information about the land below and how it is changing from year to year.

The pilots, Terry Luallen (left) and Troy Asher, make flying look easy. It was remarkable to see them work and to listen to them over the headset, says Speakman. Credits:
At work in the Gulfstream III jet are flight engineer and navigator Sam Choi from NASA’s Armstrong Flight Research Center and radar operator Tim Miller from NASA’s Jet Propulsion Laboratory. Credits: Joanne Speakman
From left: NASA pilot Terry Luallen, Mandy Bayha, NASA ABoVE Chief Support Scientist Peter Griffith, Joanne Speakman, NASA pilot Troy Asher.

August 24, 2018

NASA’s also working on building a satellite called the NASA-ISRO Synthetic Aperture Radar, or NISAR, which will help study the effects of thawing permafrost. Two of the lead scientists working on NISAR are Paul Siqueira and Bruce Chapman. While they were in Yellowknife, Mandy and I got invited to join them for a day to help collect field data.

Rock climbing isn’t the easiest in rubber boots, but Joanne Speakman and Paul Siqueira make it safe and sound. Credits: Mandy Bayha

We met with Paul and Bruce early in the morning and then drove out on the Ingraham Trail until we reached a small, marshy lake. We got out and walked along the lake’s edge, making measurements of the amount of marshy vegetation from the shore

Joanne Speakman admires a stunning view after the climb. The Northwest Territories has so many hidden gems, she says. Credits: Paul Siqueira

to the open water, an area that I learned is called inundation. We used our own estimations and also a cool device that uses a laser to tell you exactly how far away an object is. Paul and Bruce will use the information we collected that day to figure out the best way to map wetlands, which will help the ABoVE project study permafrost thaw and help with development of the NISAR satellite by comparing our results to satellite images of the area.

Mandy Bayha and Joanne Speakman use their canoeing skills. With them is NASA scientist and engineer Bruce Chapman, who Joanne is excited to learn has spent time studying the surface of Venus. Credits: Joanne Speakman
University of Massachusetts Amherst scientist Paul Siqueira enjoys the last canoe ride of the day with Joanne Speakman and Mandy Bayha. Credits: NASA/Bruce Chapman

In the afternoon, we surveyed a second lake, this time using a canoe. The sun came out and we saw ducks, a juvenile eagle, and many minnows swimming around. Nothing’s perfect, but this day was close to it and we learned a lot along the way.

Meeting and spending time with the NASA team, especially Bruce, Paul, and Peter, was the highlight of the two days. They’re incredibly kind and thoughtful and took the time to share their knowledge with us. ABoVE is a 10-year program and I hope there will be many more opportunities for northern youth to participate in such an exciting, inspiring project. There is so much potential out there. Thanks again for an amazingly fun learning experience!

In Arctic Tundra, It’s Getting Easy Being Green

A view of tundra and native spruce trees in the valley. Credit: NASA/Katy Mersmann


As I walk up the Alpine Trail in Denali National Park, I can see the vegetation changing before my eyes. Deciduous plants, like willows and smaller shrubs, start huge, as tall as my head and shoulders. But as the trail leads up, and as the altitude grows, the vegetation shrinks.

Over the course of the roughly 1,300-foot elevation gain, the plant life gets shorter and shorter until suddenly it’s almost gone—we’ve reached the tundra. By climbing up the side of this hill, we’ve mimicked traveling north into the colder parts of the Arctic, reaching the tundra much faster.

Tundra is like the Arctic’s desert: an expanse of treeless land with little available water. Most water in the tundra is below the ground in a layer of continuously frozen soil known as permafrost. Between the tundra’s low temperatures and the permafrost, it’s not a hospitable location for much plant life.

In some places, the trail bisects the hill, with large deciduous plant life on one side and tundra on the other. Credit: NASA/Katy Mersmann

On the tundra, Peter Griffith, project manager for the Arctic Boreal Vulnerability Experiment (ABoVE), points out the same shrubs we encountered lower down, although here, instead of towering over our heads, they’re only a few inches above the ground.

But that could be changing. It’s one element of the ABoVE team’s research: understanding how native Arctic vegetation responds to a warming climate.

Griffith describes the shrubs as “ready and waiting to march up the mountain.” They’re opportunistic plants, and all it takes is a little warmth and thawed ground for them to dig in and start growing larger, a process known as “shrubification” and one of the causes of the greening trends seen from long-term satellite records.

Shrubs that grow as tall as a person further down the hill carpet parts of the tundra, waiting to take advantage of slightly warmer temperatures and more available water. Credit: NASA/Katy Mersmann

As greenhouse gases change Earth’s climate, the Arctic is warming much faster than the rest of the world. And the changes are staggering. Permafrost is thawing, and the shrubs aren’t the only ones taking advantage. Within the soil, bacteria are growing and beginning to metabolize organic matter that’s been frozen in permafrost for thousands of years.

As they feast, bacteria release carbon dioxide and methane, which are released into the air. Plants like shrubs use carbon dioxide to grow even faster. In some ways, it seems like a race.

Will the bacteria respire more carbon dioxide than the growing plants can absorb? At some sites, that already seems to be the case. How this race plays out across the Arctic is another question the ABoVE team is investigating.

Using measurements of carbon dioxide and methane taken from flux towers sitting directly on the tundra, to instruments mounted on airplanes and satellites in low Earth orbit, NASA scientists are finding out how the land ecosystem influences the atmosphere in a greening Arctic, and what the consequences are for not only the Arctic but also the world.

Taking in Some Arctic Air

As the DC-8 spirals closer to Inuvik, Canada, a view emerges of the huge Mackenzie River and the standing water that flanks it. Credit: NASA/Katy Mersmann


The Arctic Boreal and Vulnerability Experiment (ABoVE) covers 2.5 million square miles of tundra, forests, permafrost and lakes in Alaska and Northwestern Canada. ABoVE scientists are using satellites and aircraft to study this formidable terrain as it changes in a warming climate.

In some ways, NASA’s DC-8 feels like a commercial airplane, with its blue leather seats and tiny bathrooms in the back. But once the plane starts to spiral down over Arctic towns, I remember I’m riding on a flying laboratory studying the amount and distribution of carbon dioxide and methane in the atmosphere.

Over the course of these big, looping spirals, the plane descends from a cruising altitude of about 30,000 feet down to just about 100 feet above the ground. The pilots fly us over the runway, as though we’re about to land, before pulling up at the last minute and returning to the sky, a maneuver known as a “missed approach.”

The DC-8 crew take turns flying out from Fairbanks, Alaska. Credit: NASA/Katy Mersmann

The whole process of spiraling down is a little scary the first few times we do it, but it’s necessary as an accuracy check for our science instruments, and by the third or fourth spiral down, it’s become a somewhat routine experience for me.

From the windows, I get a good look at the varied Arctic landscapes—twisting, braided rivers, carpets of spruce trees, and broad expanses of flat tundra all spread out underneath us. Each of those landscapes offers interesting scientific insights into how carbon emissions are changing as the climate warms.

As the DC-8 flies low over McGrath, Alaska, a tableau appears of spruce trees lining the Kuskokwim River. Spruce trees are native to the Arctic forest regions, but after frequent wildfires, some have been replaced by deciduous plants. Credit: NASA/Katy Mersmann

The plane is carrying five instruments designed to measure the spatial distribution of carbon dioxide from the air. They’re placed along the plane in place of some the seats and are operated by scientists monitoring screens mounted on their sides.

Someday, a descendent of these instruments will fly on the Active Sensing of Carbon dioxide Emissions over Nights, Days and Seasons, or ASCENDS, satellite, and the spiraling helps the researchers verify their measurements by flying right through the columns of air they’re studying from far above.

Jim Abshire is the project lead for the ASCENDS campaign. He sits near the front of the plane, plugged into the communications system and periodically checking with each instrument’s operators, making sure everything is running smoothly and requesting the occasional altitude change from the plane’s navigators.

He describes the spiral down maneuvers as a check on the lidar measurement systems, specifically ensuring that the instruments are sensitive enough to make precise measurements from space.

As Earth’s climate continues to warm, the Arctic warms much faster, and the subsequent changes in the Arctic regions are resulting in some soils releasing more carbon. More carbon in the atmosphere traps heat, causing more warming, which in turn causes the Arctic soils to release even more carbon, a process called the carbon-climate feedback.

Understanding this vicious cycle is one of the primary goals of the Arctic Boreal Vulnerability Experiment (ABoVE), a NASA campaign that includes the ASCENDS flights, as well as many other experiments, all designed to better understand how the rapid environmental change in the Arctic regions of the world impact ecosystems and society.

Mapping Methane in a Bubbling Arctic Lake

by Kate Ramsayer / FAIRBANKS, ALASKA /

At first glance, it looks like a typical, picture-perfect lake. But scan the reeds along the shore of this pool on the outskirts of Fairbanks, or glance at the spruce trees lining the banks, and you notice something different is going on.

Methane bubbles pop on the surface of a lake near Fairbanks, Alaska. Thawing permafrost in the lakebed soils releases old carbon, which microbes eat up and turn into methane. Credit: NASA/Kate Ramsayer

Bubbles. There are bubbles popping up among the reeds, like bubbles from a fish tank aerator. A couple clusters, steady streams of small half-circles, vent near the shore. Then another group appears in deeper water.

And the trees. Some of them are not growing in the directions trees normally do. They stick out drunkenly over the lake, then take a turn upwards at the top.

A lake near Fairbanks shows signs of thawing permafrost below the surface – including "drunken trees" that tip over as the soil shifts around its roots. Credit: NASA/Kate Ramsayer
A lake near Fairbanks shows signs of thawing permafrost below the surface – including “drunken trees” that tip over as the soil shifts around its roots. Credit: NASA/Kate Ramsayer

The explanation for both of these features is in the soil. Permafrost—soil that remains frozen year-round—lies underneath the moss, needles and topsoil of the site. As that permafrost thaws, the ground above it can sink, knocking trees askew and forming pools of water called thermokarst lakes.

“The carbon locked in permafrost for thousands of years is released to the lake bottom,” said Prajna Lindgren, a postdoctoral researcher at the University of Alaska, Fairbanks, Geophysical Institute.

These lake beds, she explained, provide a perfect environment for microbes to eat up the carbon released from the thawing permafrost. This produces methane—a potent greenhouse gas that is released in bubble seeps. As part of the NASA-funded Arctic Boreal Vulnerability Experiment, or ABoVE, Lindgren and her colleagues are studying these seeps and mapping how thawing permafrost is affecting the changing lake edges.

Methane bubbles in a lake.
A methane seep releases bubbles in the grasses close to the shore of a lake near Fairbanks, the site of thawing permafrost. Credit: NASA/Kate Ramsayer

“We’re trying to establish the amount of methane that’s released from these lakes,” she said.

To do that, the scientists are combining old aerial photos with satellite images and new surveys of lakes across Alaska. They’re looking at how the shapes and sizes of lakes are changing over time, which is an indication of where permafrost thaw is altering the landscape. Then, they examine how changing landscapes are associated with the methane seeps. In the fall, as soon as the lakes freeze over, the bubble-measuring fieldwork begins.

“If there’s no snow on the lake and its just black ice, when you walk out you see distinct bubbles in the lake ice,” Lindgren said. The methane bubbles get trapped in the ice, fusing together in pancake shapes, that the researchers can plot and measure.

“We see a lot of these seeps clustered where the lakes are changing,” she said. The next steps will be to estimate methane release based on the extent of lake changes. And for lakes beyond the researchers’ reach, such as those in remote areas of Alaska and northwestern Canada, the goal is to estimate methane release based on how the lakes are changing, as seen in satellite images.

A new study, funded in part by ABoVE, compared old aerial photos from the 1950s with recent satellite images to measure changes in lake outlines, for example. Using this information, methane measurements, radiocarbon dating and other techniques, the scientists calculated how much old carbon, stored for thousands of years in the permafrost, has been released over the past 60 years.

Burrowing into the Arctic’s Carbon Past and Future

The Permafrost Tunnel provides a look back in time, allowing for research into the frozen ground of interior Alaska. Credit: NASA/Kate Ramsayer
The Permafrost Tunnel provides a look back in time, allowing for research into the frozen ground of interior Alaska. Credit: NASA/Kate Ramsayer

by Kate Ramsayer / FAIRBANKS, ALASKA /

“What we’re going to do is walk back in time,” said Matthew Sturm, standing in front of a doorway that led into a hillside north of Fairbanks, Alaska.

Through the doors was a tunnel that provides access to the Alaska of 40,000 years ago, when bison and mammoths foraged in grassy valleys. Now, however, the grasses and the animal bones are frozen in the ground in the Permafrost Tunnel.

The tunnel, run by the U.S. Army’s Cold Regions Research and Engineering Laboratory, was dug in the 1960s and is the site of much research into permafrost—ground that stays frozen throughout the year, for multiple years. Sturm, a professor and snow researcher at the University of Alaska, recently led a group with NASA’s Arctic Boreal Vulnerability Experiment (ABoVE) to the site. The walls of the tunnel expose the silt, ice, and carbon-rich plant and animal matter that has been frozen for tens of thousands of years.

“It’s a legacy of the Ice Age,” Sturm said. Roots of long-buried grasses hang from the ceiling, in a few places bones of Pleistocene mammals are embedded in the wall.

Scientist in a permafrost tunnel
Matthew Sturm points to some grasses and sticks that were buried during the Ice Age and frozen in the ground and now exposed in the ceiling of the permafrost tunnel. Credit: NASA/Kate Ramsayer

What will happen to the carbon contained in permafrost in the Alaska interior and elsewhere in the northern latitudes is a major question for NASA’s ABoVE campaign, which is studying the impacts of climate change on Alaska and northwestern Canada. Temperatures are rising in the Arctic region, which means permafrost is thawing at faster rates—and when it thaws, it releases carbon dioxide or methane into the atmosphere.

One ABoVE project is taking steps to monitor the temperatures of the permafrost across Alaska to see how far below the surface it is frozen and whether the temperatures of the soil layers are changing.

“We’ll get temperature data across large territories to supplement the existing data,” said Dmitry Nicolsky, with the University of Alaska, Fairbanks. Most of the existing data is along easy-to-access roads—but there aren’t many roads in Alaska. Nicolsky and his colleagues are working with researchers at USArray, which is establishing earthquake-monitoring stations across the state. Those crews are also drilling about 20 boreholes for thermometers this year, with more planned.

Man working outside
Dmitry Nicolsky demonstrates how sensors are inserted into a borehole to measure the temperatures of layers of soil and permafrost at different depths. Credit: NASA/Kate Ramsayer

Nicolsky has been getting the instruments ready for deployment. Crews will install lines that have six temperature sensors at six different depths, from just below the top mossy layer to more than 6.5 feet below the surface. They’ll take readings several times a day for three to five years to help the scientists get a more complete picture of how temperatures in Arctic soil are changing.  

Taking Measure of a Remote Slice of Alaskan Forest

Kate Legner points out the next tree in the survey site as other crew members measure key information about the vegetation in a 53-foot diamter plot. Credit: NASA/Kate Ramsayer
Kate Legner points out the next tree in the survey site as other crew members measure key information about the vegetation in a 53-foot diamter plot. Credit: NASA/Kate Ramsayer

by Kate Ramsayer / SALCHA, ALASKA /

In a birch forest in interior Alaska’s Tanana Valley, there’s a stake with pink plastic tape attached. More than three decades ago, a plane flew over it to take stereoscopic pictures of the surrounding plot, and scientists trekked out to survey the trees and vegetation. Now, scientists are re-flying and re-surveying the site, using advanced airborne instruments and satellite images to track changes in interior Alaska.

“This is going to be 10.3,” called out Sean Cahoon, a scientist with the University of Alaska, Anchorage. He was standing at the end of a tape measure radiating out from the stake, using another tape measure to check the diameter of the base of a birch tree.

Birch trees, numbered in yellow, have been measured as part of the site survey. Credit: NASA/Kate Ramsayer
Birch trees, numbered in yellow, have been measured as part of the site survey. Credit: NASA/Kate Ramsayer

Kate Legner, with the University of Washington in Seattle, recorded the number as well as the diameter at breast height, the distance from the stake, and the azimuth (angle from due north) of the tree’s location.

“That’s all you need to recreate this whole area,” Legner said. The area in question is a circle with a 53-foot radius out from the stake. Mostly birch, with a few aspen and white spruce trees, just sparse enough to let some sun filter through to shrubs, seedlings, moss and lichens thick on the ground.

ABoVE scientists measure a field site in interior Alaska's Tanana Valley, which has been monitored from the ground, airborne instruments and satellites to track changing ecosystems. Credit: NASA/Kate Ramsayer
ABoVE scientists measure a field site in interior Alaska’s Tanana Valley, which has been monitored from the ground, airborne instruments and satellites to track changing ecosystems. Credit: NASA/Kate Ramsayer

The recreation of this and other plots in the Tanana Valley is a key part of the NASA-funded Arctic Boreal Vulnerability Experiment, or ABoVE. Scientists will compare ground surveys to surveys from 35 years ago, along with aerial photos from similar time periods. They’ll also incorporate data from NASA Goddard’s Lidar, Hyperspectral, and Thermal (G-LiHT) airborne imager, which provides vegetation heights and composition information along sample strips throughout the valley.  The times between these ground and airborne observations are filled by periodic image data from Landsat satellites. Landsat provides a more continuous record of change, but the coarse resolution of the data does not capture tree-scale information.   

“Our overall objective is to make use of a really rich historical inventory dataset that we have available,” said Hans Andersen, an ecologist with the U.S. Forest Service and co-investigator on the project. “We’ll be interested in changes in the vegetation cover that could be due to climate change over that period of time.”

The different sources of data complement each other, he said. Ground surveys allow researchers to identify and count individual trees, while aerial photos can cover more ground. The strips of G-LiHT data, covering the valley and collected by NASA Goddard’s Bruce Cook, who is leading the project, provide high-resolution data of tree heights, species composition and moisture conditions of the site.

Every time a Landsat satellite passes overhead and captures a cloud-free image, the team adds that to the data record as well. It’s not a coincidence that the 53-foot-radius plot matches up with a single Landsat pixel, Andersen said.

And it’s not just tree composition that the crew is interested in. As Legner and Cahoon were measuring and marking trees, Andersen and the fourth member of the survey crew were nearby digging a hole, collecting soil samples in plastic zippered bags.  

“The soil samples are all about the carbon,” said Robert Pattison, with the U.S. Forest Service’s Anchorage Forestry Sciences Laboratory. “For interior Alaska, it’s really the biggest story.”

One new element to the survey protocol: taking soil samples at different depths to check carbon content. Credit: NASA/Kate Ramsayer
One new element to the survey protocol: taking soil samples at different depths to check carbon content. Credit: NASA/Kate Ramsayer

This summer, the crew is refining their field sampling protocols and investigating “road-accessible” sites. The birch site was a half-mile scramble up a hillside covered in prickly bushes and thick shrubs, with fallen trees and branches providing additional obstacles.

Next year, the crew will use helicopters to get to even more inaccessible sites across the Tanana Valley. They’ll survey about two dozen representative sites, measuring trees, soils and other sources of carbon, with the goal of making computer models to relate those findings to sites across the valley.

“The end product is essentially an estimate of carbon in various places across the entire Tanana,” Andersen said.

Living Off the Land in a Changing Arctic Climate

Moose are one of the main resources for subsistence hunters in Alaska. Areas that are recovering from a low-severity wildfire can attract the ungulates. “If we didn’t have fires ripping through, we would have fewer moose walking through here and fewer full freezers,” said Todd Brinkman, an assistant professor at the University of Alaska, Fairbanks. Credit: NASA/Kate Ramsayer

by Kate Ramsayer / FAIRBANKS, ALASKA /

Scrambling up the bank of the Tanana River south of Fairbanks, Theresa Hollingsworth was looking for examples of how the forest recovers after a wildfire. She found an unexpected sweet surprise.

“Blueberries!” she yelled from the banks.

Gathering handfuls, she instantly planned a return trip later in the week to go picking. “You fill your freezer with as many berries as you can.”

It’s a way of life for many Alaskans, said Hollingsworth, a research ecologist with the U.S. Forest Service’s Pacific Northwest Laboratory. People have favorite—often secret—berry spots they go back to year after year. They also hunt and fish, stocking freezers with moose and salmon and other game.

For many Alaskans, summer is time to stock freezers with blueberries. Credit: NASA/Kate Ramsayer
For many Alaskans, summer is time to stock freezers with blueberries.
Credit: NASA/Kate Ramsayer

Many of the rural villages in this giant state—more than twice the size of Texas—aren’t connected with roads, said Todd Brinkman, an assistant professor at the University of Alaska, Fairbanks.

“The road network for a lot of these rural communities is on the rivers, or trail networks through the woods,” he said. “That’s their access to the grocery stores—grocery stores being the forests around them.”

But many residents are reporting that the changing environment is creating obstacles to how they reach these resources. So Brinkman and Hollingsworth are working on a research project with the NASA-funded Arctic Boreal Vulnerability Experiment, or ABoVE, to investigate how access to game, berries, and neighboring villages is changing in a warming climate.

In March, Brinkman gave camera-equipped GPS units to subsistence hunters in eight or so villages across Alaska. Over the next year, the residents will document anything that blocks or hinders their travel, whether it’s an early thaw of river ice, a wildfire, a trail sunk by thawing permafrost or something the researchers haven’t yet thought of.

“We’re letting the subsistence users really drive the research,” Hollingsworth said.

In one area, for example, women were wary of collecting blueberries in their traditional spot, since a wildfire had torn through and left dead trees in danger of toppling over. Wildfires can also change the types of plants that grow back, which in turn could impact the wildlife as well as the people living nearby.

Scientist looks at plants.
Theresa Hollingsworth examines the moss and lichens on a forest floor. Credit: NASA/Kate Ramsayer

Rural residents have also noted changes to the rivers, Brinkman said. People boat along rivers in summer and use them as a snowmachine trail in winter, but the in-between periods while the ice is breaking up or forming make travel incredibly difficult. If a warming climate means early ice break-up, it’s significant to people who depend on that river, he said.

The character of some rivers is also changing. Residents are noting that the permafrost in the banks is thawing, leading to erosion. More erosion means wider rivers, which also means shallower rivers.

“Where the permafrost is exposed, it’s challenging navigating on a lot of these river systems,” Brinkman said.

A river.
The Tanana River south of Fairbanks, Alaska. For many rural residents, rivers are an important transportation route.
Credit: NASA/Kate Ramsayer
A riverbank.
Brinkman looks at a riverbank of thawing permafrost, which is dripping water and sending clumps of soil into the river. Credit: NASA/Kate Ramsayer

After a year’s worth of these disturbances are recorded, Hollingsworth and others will examine the sites. They’ll analyze remote sensing images, including those from Landsat satellites, for before-and-after comparisons. They’ll visit the site, inventory the ground cover and trees and take soil samples and other measurements to get a sense of what is happening with the ecosystem. The researchers can also use remote sensing images to relate changes to access in one place to changes that could be happening in similar ecosystems.

And they’ll talk with the residents about how these changes are impacting their everyday lives, Brinkman said. “We’ll start to understand the types of disturbances we should dig into.”

Tower Power: Measuring Carbon in the Last Frontier

Alaska boreal forest
The boreal spruce forests of interior Alaska are visible from the top of a tower that measures greenhouse gasses for the ABoVE project. Credit: NASA/ Kate Ramsayer

On a clear day from atop a 100-foot tower on a peak north of Fairbanks, you can see 100 miles in every direction. The rolling hillsides are covered in black spruce, white spruce, some birch, with shrubs and moss beneath them.

For Chip Miller, deputy science lead for NASA’s Arctic Boreal Vulnerability Experiment, or ABoVE, it’s an unmatched view of the region’s carbon.

“You see the boreal forest of interior Alaska and all of the above-ground carbon that’s stored there,” he said. “And it’s carbon dioxide that’s been sucked out of the atmosphere by all of those trees and all of those plants.”

The ABoVE field campaign is studying how Alaska and northwest Canada are changing in a rapidly warming climate. On the hot Wednesday morning of July 13, Miller checked in on the tower that has played a key role in tracking the changes in greenhouse gases since 2011.

“There are such massive amounts of carbon dioxide exchanged between terrestrial biospheres and the atmosphere, and they vary quite a bit from year to year, and even month to month, week to week or day to day, depending on climate conditions,” said Miller, a researcher with NASA’s Jet Propulsion Laboratory. “We make these measurements here at the tower, 24/7, 365 days a year, to give us that continuous record of what’s going on with the carbon cycling.”

Instruments on the tower, which is operated by the National Oceanic and Atmospheric Administration, measure the amount of carbon dioxide, carbon monoxide and methane in the air. The tower measures gases that drift in from as far away as Canada and the Brooks Range in northern Alaska.

The tower has instruments along its scaffolding to take measurements of the air above interior Alaska. Credit: NASA/Kate Ramsayer
The tower has instruments along its scaffolding to take measurements of the air above interior Alaska. Credit: NASA/Kate Ramsayer

Carbon dioxide is the most important greenhouse gas that’s exchanged between the atmosphere and the vegetation on the ground, Mlller said. Methane is a potent greenhouse gas that is released from wetter ecosystems. Carbon monoxide is a key product of wildfires and so helps scientists detect when a burn is releasing the carbon stored in forests into the atmosphere, he said.

While 2016 has so far not been a big fire year for interior Alaska, last year about 5 million acres burned, he said, noting that large fires could send smoke billowing across the landscape.

“The acrid quality of the air would make a heavy pollution day in Los Angeles or Beijing look like nothing,” he said.

The tower has instruments along its scaffolding to take measurements of the air above interior Alaska. Credit: NASA/Kate Ramsayer
The tower has instruments along its scaffolding to take measurements of the air above interior Alaska. Credit: NASA/Kate Ramsayer

Since the tower started collecting measurements, Miller and his colleagues have been analyzing the data. They can identify individual fire plumes that drift toward the tower. And when they compare measurements year to year, they’ve found that there’s a lot of variability year to year in carbon dioxide—but not necessarily of the methane.

“We’re still trying to understand why the methane is not varying as much as we think it might,” Miller said. “That’s part of the ongoing scientific investigation.”

Keeping Scientists in the Arctic Safe and Supplied


by Kate Ramsayer / FAIRBANKS, ALASKA /

With more than three dozen research groups scattered across 2.5 million square miles of Alaska and northwest Canada, somebody’s bound to need some last-minute chicken wire.

When one group with NASA’s Arctic Boreal Vulnerability Experiment, or ABoVE, discovered that Arctic hares were nibbling into their experiments, Sarah Sackett, the Fairbanks ABOVE logistics coordinator, made sure they got the protective equipment they needed.

Sackett’s role in ABoVE starts early on in a team’s field season. She provides safety and logistical support to researchers, works with them to identify what kinds of hazards they might run into and what specific training they need, from bear safety to proper handling of an off-road vehicle to the need for hydration even in the cold.

ABoVE Fairbanks logistics coordinator Sarah Sackett not only provides safety and logistics support to researchers in the field, she ventures out to collect data for scientists as well. Here, she demonstrates how to measure photosynthesis in spruce needles. Credit: NASA/Kate Ramsayer
ABoVE Fairbanks logistics coordinator Sarah Sackett not only provides safety and logistics support to researchers in the field, she ventures out to collect data for scientists as well. Here, she demonstrates how to measure photosynthesis in spruce needles. Credit: NASA/Kate Ramsayer

“We start training with the very basics, because we might have graduate students from New York, brand new to the field, all the way to people who have been out in the Arctic field for years,” said Sackett, a Fairbanks native.

At ABoVE’s new office in Fairbanks, Sackett and the logistics team is building a lending library of equipment: tents, satellite phones, cooking equipment, tarps, rain boots, mosquito nets, even high-tech GPS units that can locate a remote spot to a fraction of an inch. ABoVE is a decade-long field campaign, and having stocked shelves of equipment for researchers to check out as needed will be convenient and cost-effective for the effort.

In addition to providing needed hardware to researchers, Sackett helps with logistics, from flight arrangements to truck rentals. She works closely with Dan Hodkinson and Leanne Kendig back at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who are key to the effort, Sackett said.

“The little details are where it counts, so we start as early as we can,” she said. “I like putting all the little pieces together to make the big picture work.”

ABoVE staff scientist Peter Griffith, of NASA’s Goddard Space Flight Center, practices deploying bear spray. "Wait until it’s closer than you’re comfortable with," advises Sarah Sackett, who provides safety training for scientists heading out into the field. Credit: NASA/Kate Ramsayer
ABoVE staff scientist Peter Griffith, of NASA’s Goddard Space Flight Center, practices deploying bear spray. “Wait until it’s closer than you’re comfortable with,” advises Sarah Sackett, who provides safety training for scientists heading out into the field. Credit: NASA/Kate Ramsayer

And as she’s handling the planning and organizational side of the job, she’s learning how to do the science as well. One researcher trained her how to use a device to take measurements of needles of a spruce tree. Now she will go up monthly to collect and download the data, saving the out-of-state researchers a long trip.

“I was hoping that’d be part of the job,” Sackett said, noting that she won’t look at trees the same way again. While she’s excited to help with more of the field experiments in the future, she also loves working with the teams to solve problems and ensure they can do their work in often-difficult terrain and harsh conditions.

“It’s pretty much the best job ever,” Sackett said. “My boss is like, ’figure this out,’ and I’m like, ’OK!'”