Delivering Boardwalk

May 10, 2010

PFSers Larry Gullingsrud and Annelisa Neely deliver boardwalk to Mike Weintraub's tundra plots at Imnavait Creek. Researchers will use the dark material in the background to artificially warm some of the tundra plots. Photo: Jason Neely

University of Toledo’s Mike Weintraub returned to Imnavait Creek near Toolik Field Station last week for the first full season of tundra plot studies supported by his recent NSF grant.  The project is one of a group of new research to be fielded at/near Toolik this year to study changing seasonality in the Arctic (CSAS).  Specifically, Weintraub’s team is looking at how altered timing of seasonal events—earlier spring thaw and later fall freeze, for example—may affect nitrogen cycling in the soil, and how that in turn impacts tundra plant and microbe growth.

Polar Field Services staff returned to Toolik in late April for spring science support and station facilities projects. Among the larger science efforts, Jason Neely’s team placed about 3000 linear feet of boardwalk out on Imnavait Creek tundra manipulation plots for Weintraub’s CSAS soil nutrient experiment.   The boardwalk protects the fragile, slow-growing tundra from the many footsteps of researchers visiting the plots to collect plants, data and/or to manipulate the conditions.  The Weintraub team will continue working on the CSAS project for the length of the summer season at Toolik Field Station, departing in late August.

Weintraub heads an interdisciplinary collaboration composed of four other PIs:  Paddy Sullivan (U Alaska), Josh Schimel (U California), Edward Rastetter (Marine Biological Laboratory), and Heidi Steltzer (Colorado State U).

Researchers will manipulate the timing of seasonally driven processes in tussock tundra ecosystems by advancing the timing of snowmelt with radiation-absorbing fabric placed over the snowpack in the late spring and by using open-top warming chambers in concert with advanced snowmelt. They will follow how seasonally driven plant and soil dynamics are affected by changes in the timing of snowmelt and warming.


When the ground collapses like a soufflé: Studying the effect of thermokarst on the Arctic

December 28, 2009

By Emily Stone 

This is the thermokarst failure on a stream leading into the Toolik River on the day Breck Bowden and Michael Gooseff discovered it in 2003. (Courtesy of Michael Gooseff)

Scientists Breck Bowden and Michael Gooseff were flying in a helicopter near Toolik Field Station in 2003, scouting for good field sites for river research when they spotted something peculiar. 

Unlike the crystal clear Kuparuk River nearby, the Toolik River was a muddy brown, an unusual site in the Arctic where tundra streams don’t pick up much sediment because the ground is usually frozen. The men had the helicopter fly upstream to investigate. After 40 kilometers they saw the culprit: a small stream leading into the river had a huge, narrow crater on its shore that was dumping sediment into the river. 

“It was a severe gash on what was otherwise a nondescript hillside,” said Gooseff, an assistant professor of civil and environmental engineering at Pennsylvania State University. 

The feature is what’s known as a thermokarst failure. Thermokarst occurs when ice in the usually solid permafrost melts and the land gives way like a soufflé. When this happens on flat ground, the melted water pools into a thermokarst lake. When it happens on a slope, as was the case along the Toolik, the water rushes downhill and usually into a nearby body of water and the ground slumps after it, causing what’s called a thermokarst failure. 

The helicopter landed by the gash. Bowden, a professor of watershed science and planning at the University of Vermont who is over six feet tall, was engulfed in it when he stood at the bottom. He guesses that it had formed within a few days of their arrival. 

Standing there, he remembers looking around at all the other tiny streams that led into the region’s big rivers and thinking, “It wouldn’t take many of these on the landscape to have a fairly big impact.” 

Bowden is now leading a project that includes Gooseff and 15 other principal investigators to discover what exactly these thermokarst features are doing to the landscape and river networks, and how they form in the first place. They’ve already established that there are many more of them than there were 25 years ago, the likely result of rising temperatures in the Arctic. As more thermokarst failures develop, researchers want to know how the additional nutrients dumped into rivers will affect aquatic ecosystems, how they’ll impact the plant communities that grow back after a thermokarst landslide, and how they’ll change the amount of carbon dioxide and methane being released into the atmosphere — all crucial questions in the study of climate change. 

Breck Bowden explores the thermokarst failure on a stream leading into the Toolik River on the day he and Michael Gooseff discovered it in 2003. (Courtesy of Michael Gooseff)

Downstream of the same thermokarst feature as it looked this summer when the group of researchers began their multi-disciplinary study of the phenomenon. Photo: Emily Stone

The group, which includes another couple dozen graduate students and technicians, is in the first year of a four-year, $5-million grant from the NSF’s Arctic System Science Program. They spent their first field season at Toolik this past summer picking their research sites and setting up equipment to monitor the changes happening in and near the thermokarst failures. 

Previous research by Bowden, Gooseff and some of the other collaborators established that, at least in the area around the field station, there are many more thermokarst failures than there were in the early 1980s. The group did an aerial survey of 600 square kilometers around the station and compared their observations to an aerial survey that was done in the same area around 1980. They found 34 thermokarst, two-thirds of which were new. This data doesn’t necessarily correspond to the rest of the Arctic since different soil conditions, slope and climate affect thermokarst formation, but it does suggest that the features are growing in at least one large swath of Alaska. 

The concern is that these features can have an outsized impact on the environment. 

Bowden is interested in the nutrients that are usually held frozen in permafrost — what he describes as “brown concrete” — that are released into rivers when that permafrost melts. The addition of ammonium, nitrate and phosphate means that aquatic microbes and plants have much more to eat and can flourish in areas where their populations were previously limited by a lack of food. This can dramatically alter a river’s ecosystem. 

He has set up water monitoring stations on rivers above and below thermokarst failures to compare the sediment and nutrients in the water before and after the thermokarst soil reaches it. Earlier research showed that the Toolik River thermokarst failure delivered more sediment to the river than was dumped into the Kuparuk River over the course of 18 years from a 132-square-kilometer section of watershed. 

Other researchers in the group are looking at how plants react to thermokarst failures. “We have a suspicion that what they evolve into is a shrubby community,” Bowden said, instead of the low tundra grasses that dominate the region. 

This is important because shrubs hold on to more sunlight than grasses, which warms the soil below. This can in turn release more stored carbon out of the warming soil. Additionally, warmer soil releases more nutrients for microbes to use as fuel. Microbes then release more methane into the atmosphere, which is a powerful greenhouse gas. Scientists in the thermokarst group are measuring this CO2 and methane release. 

Other researchers are looking at remote sensing and computer modeling, as well as interviewing Native Alaskan communities nearby to learn about their memories of where thermokarst have occurred in the past. 

Gooseff is taking a step back to try to figure out what causes the thermokarst failures in the first place. He has placed water and temperature sensors at various depths in and near several thermokarst features, as well as instruments above ground that measure rain, snow, sun and wind. His post doc, Dr. Sarah Godsey, set up cameras to take pictures of the thermokarsts every hour. Their goal is to be able to correlate the weather and soil data with physical changes in the permafrost and landscape. 

Bowden notes that thermokarst are not a new occurrence. Scientists have been aware of them for years, and engineers have long studied them in the context of building roads, homes and pipelines. 

“It is a natural phenomenon, but it appears to be one that is accelerating,” he said.

Emily Stone is a freelance writer from Chicago, Illinois. She spent a week at Toolik Field Station in 2009 as an MBL journalism fellow.


In the Media

October 7, 2009

Spotlight on Toolik Field Station Research

Toolik Field Station

Toolik Field Station

Science journalist Leslie Dodson has released some videos recorded at Toolik in 2008 for the Video Journalism Movement. The VJ Movement facilitates collaborations between a global network of freelance video journalists, editorial cartoonists and the public. Participating in the Wood’s Hole Marine Biological Lab Science Journalism Fellowship, Dodson trailed Toolik LTER scientists and others two summers ago to get the footage.  The following short Dodson videos featuring CPS-supported scientists are an engaging watch.

Searching for Plankton in Toolik: http://vjmovement.com/truth/66

The 2007 Anaktuvak Fire: http://vjmovement.com/truth/185

Enjoy!


All in the Family

September 25, 2009

A Toolik scientist brings her children to the field

By Emily Stone 

Sally MacIntyre and her son, Johnny Melack, on Toolik Lake in 2003 when Johnny came to help his mom with her research.

Sally MacIntyre and her son, Johnny Melack, on Toolik Lake in 2003 when Johnny came to help his mom with her research. Photos courtesy Sally MacIntyre

Sally MacIntyre’s research studying the physics and biology of lakes has taken her to some amazing research sites, including Toolik Field Station. But over the years it also meant leaving home — and her two children — for up to a month at a time.

“That’s one of the challenges of being a mom,” she said. “You don’t really ever want to be away from your kids.”

In the back of her mind on these trips, she always thought that it would be great if she could bring her kids with her. She eventually did just that. Her 20-year-old daughter, Megan Melack, spent 10 days this summer working with her at Toolik, just as her son, Johnny Melack, did as an 18-year-old in 2003.

Megan Melack spent 10 days at Toolik Field Station this summer helping her mother, Sally MacIntyre, deploy instruments that measure temperature and turbulence in Toolik Lake below the surface.

Megan Melack spent 10 days at Toolik Field Station this summer helping her mother, Sally MacIntyre, deploy instruments that measure temperature and turbulence in Toolik Lake below the surface.

MacIntyre, a professor at the University of California, Santa Barbara, said it was important that she wait until her children were old enough to appreciate Toolik, both the stunning physical beauty of the place and the community of smart, engaged scientists. She wanted Megan and Johnny to have a social life independent from her, “so it becomes their place too, not just that they’re hanging out with mom.”

The strategy clearly worked.

“I can’t even explain how happy I am that I went there,” said Megan, who is a junior at the University of California, Santa Cruz. “I tell people that my soul was revived.”

Megan had been skeptical of the trip, which her mom had been urging her to make for a few years. She worried that as a self-described “girly” Californian, the giant mosquitoes and primitive living arrangements — outhouses and limited showers — wouldn’t suit her. But she quickly learned to deflect the mosquitoes and got used to the camp’s amenities, or lack thereof, and turned her attention to the people and science around her.

The highlight of the trip was a midnight hike with a small group the night before she left. “I can’t imagine doing that anywhere else in the world with such awesome people,” she said.

The science became real to her, too.

“There’s no way you ever truly understand scientific research unless you go out and do it,” she said. And she suddenly understood what her mom had been doing all those years when she headed off into the field.

Megan Melack helps her mother, Sally MacIntyre, deploy instruments in Toolik Lake that read the temperature and turbulence of the water below the surface.

Megan Melack helps her mother, Sally MacIntyre, deploy instruments in Toolik Lake that read the temperature and turbulence of the water below the surface.

“It made me very proud to see all the things she does out there,” Megan said.

MacIntyre studies the turbulence below the surface of Toolik Lake. Arctic lakes are much more turbulent than similarly sized and, in some cases, much larger temperate lakes. That means that more nutrients are mixed from the bottom into the water column above where there is light to support the growth of tiny phytoplankton. The mixing rates are so high because the difference in water temperature from the top of the lake to the bottom isn’t that great. But if the climate were to warm significantly, that difference would increase and it could cut off the underwater churning. Megan and Johnny helped their mom deploy instruments that read the lake’s temperature and turbulence from the top to the bottom as part of MacIntyre’s ongoing research.

Johnny, who was about to start school at the University of California, Davis, the summer he was at Toolik, had always been interested in science. He now works as a mechanical engineer for a company making hydrogen fuel cells in Davis. During a summer break in college he spent part of his time working with the company that builds MacIntyre’s instruments, and he helped build one of hers. He inscribed “To Mom from Johnny” on it.

“It’s totally wonderful,” MacIntyre said. 

Sally MacIntyre studies the turbulence below the surface of Toolik Lake. She's been able to bring both her children to the camp as young adults to help her with her research.

Sally MacIntyre studies the turbulence below the surface of Toolik Lake. She's been able to bring both her children to the camp as young adults to help her with her research.

Megan, who is majoring in psychology, had been thinking about studying a hard science as well, and said her time at Toolik convinced her that she should. She’s planning to add either an environmental studies or biology minor and is thinking about science journalism or environmental policy lobbying as a career. She’d also like to figure out a way to go back to Toolik, perhaps with a project of her own someday.

They worked hard while at Toolik, so it’s no surprise that Johnny and Megan both enjoyed their time off, too.

Johnny spent much of his free time filming a documentary video about the place, hiking, and playing soccer and basketball under the midnight sun. Megan was an ebullient presence at the camp, chatting easily with people at meals and social activities. She and MacIntyre were both enthusiastic participants in the station’s re-enactment of Michael Jackson’s “Thriller” dance shortly after his death.

MacIntyre said she was grateful for the warmth both old-timers and newcomers at the camp showed Johnny and Megan.

“The fact that people at Toolik reached out to my children made their experiences so positive,” she said.

MacIntyre’s research at Toolik is part of the Arctic LTER program, which is funded by the National Science Foundation.

Emily Stone is a freelance writer. She spent a week at Toolik Field Station last summer as an MBL journalism fellow.


Postcards from Toolik

June 22, 2009

Emily Stone is a Chicago-based freelance writer. She’s on a 16-day science journalism fellowship at Toolik Lake through the Marine Biological Lab (MBL).  

Linda Deegan, a senior scientist at MBL who studies an arctic fish called the grayling, doesn’t need to see temperature stats to know that the climate around Lake Toolik is changing. She just has to check her travel calendar.

Lisa Jarvis, a writer at Chemical & Engineering News, and David Gallagher, MBL Web Editor, take insect samples from the Kuparuk River Sunday as part of MBL's science journalism fellowship. Story and photo: Emily Stone

Lisa Jarvis, a writer at Chemical & Engineering News, and David Gallagher, MBL Web Editor, take insect samples from the Kuparuk River Sunday as part of MBL's science journalism fellowship.

When Deegan started coming to Toolik in the 1980s, scientists like herself who are interested in water didn’t get to station until late June or early July. In recent years the ice out date has gotten earlier and earlier and she now arrives earlier and earlier to do her science. We spent the day with her on the Kuparuk River today, testing the water for nutrients and insects.

Deegan has noticed a dramatic difference in the grayling population on the Kuparuk. In the mid-90s, when she strung a net across the river for two weeks, she’d collect 2,000 to 3,000 fish. When she did the same test a few years ago, she only caught 700.

“The biology is telling us that the system is changing,” she said.

She believes the culprit is a number of dry years that are causing the rivers to dry out in spots. Grayling, like all arctic fish, must get out of the rivers during the winters because they freeze solid. Some fish, like salmon, head to the oceans. Others, including the grayling, swim to deep lakes that retain open water below an icy surface. But if the rivers don’t run straight through to the lakes the grayling can’t reach their winter homes and they die.

The overall population of grayling in the Arctic is healthy, Deegan said. But she’s worried that if the Kuparuk population gets hit with many more drought years, they may fall below sustainable levels.

Deegan is also interested in what the earlier ice out dates will mean for trout, which prey on the grayling in their winter lakes. Trout need light to feed, so the start date for their hunting is fixed. (Global warming doesn’t change the cycle of daylight, of course.) So if the rivers warm up sooner and sooner and the grayling take off into the rivers sooner and sooner, the trout will have fewer days in which to eat.

The MBL science journalism program (funded by the National Science Foundation) gives journalists an overview of the climate science happening at the field camp. It’s also designed to give the reporters a sense of the painstaking process of conducting research by having them go out in the field and collect samples and then analyze and interpret the data.  Emily Stone will be writing about what she’s learning and seeing during her stay.


Follow

Get every new post delivered to your Inbox.

Join 95 other followers