Published in the Antarctic Sun
It’s early morning. Most folks are struggling to get to work with coffee in hand. But several brighteyed, low-paid men and women are bouncing off the walls in the GA shack next to the carpenters’ shop at McMurdo.
Led by former general assistant Sally Lyon, this season’s operations GAs are ready to work. Lyon doles out the day’s tasks.
"Heather, you’ll go to waste. Lynn, you’ll go to the galley, but it’s just for the morning," Lyon says. She also sends two GAs in a Spryte to replenish the Penguin Ranch fuel supply. The remaining two head out to Williams Field to re-flag a route on the ice shelf.
These operations GAs are not the only ones in town. But the work of several other GA's assigned is with designated departments in town, such as facilities maintenance and fuels department, is bit more specialized.
The nine operation GAs are the ones out shoveling snow, moving boxes, entering data and generally helping out all around McMurdo Station.
It doesn’t take a lot of training to be a GA, though they do go to happy camper and sea ice schools early in the season. But it does take a certain type of person.
Lyon picks her crew carefully from a pool of applicants that by far outnumbers the number of positions available. They're all seeking a job with adventure. "The variety is what attracts most people," Lyon said.
Most of the people she picks, Lyon said, are flexible and have a sense of humor as well as
a broad range of life experiences. This year’s GAs include a former Peace Corps volunteer,
a former tour director with the Ringling Bros. and Barnum & Bailey Circus, and a person
who worked with delinquent youth.
But there is one characteristic that pervades all else in the application process, Lyon said: "Somehow they’ve made it clear that they will do anything to get here."
This means Lyons doesn't have to sell the job; she even tries to discourage applicants. She starts an interview by telling them about the worst parts of the job. If they still sound positive, she tells them the good parts.
As the season progresses, work varies a bit, but not always enough. Sometimes GAs end up doing the same thing for several days. Though from the beginning they were told that this would almost certainly happen, it is still sometimes difficult.
When the job does change every day, on the other hand, there’s different challenge. "You don’t see the big picture," said GA Lynn Keating. A day-long task for a GA may be part of a month’s worth of effort for everyone else; having a sense of closure about a project is rare.
Lyons tries to mix up the tasks among the group a bit, to keep them interested in what’s going on, and to keep them learning about how the station operates. "My goal is that they’re as excited to work on January 20 as October 20," Lyon said.
She reminds them to be aware of where they are and how amazing it is. "When you’re shoveling, don’t forget to look up," Lyon said.
In addition to becoming well-rounded in operations, being a GA is a good way to make a good impression on people who will be hiring for next season. "It’s a great springboard," Lyon said.
All of last year’s McMurdo GAs came back for another season, whether for winter at Palmer or in town this season. Many more ex-GAs work all over town and throughout the Antarctic program.
"Everywhere you go, there’s former GAs," said GA Heather Reider.
From those former GAs and the quality of work of each year’s crew, the word is spreading
that GA labor is valuable, Lyon said. "People are starting to recognize that there’s an incredible amount of talent in this group," Lyon said.
Lyon’s combination of practicality and motivation works out well for her and for the GAs. Most of them are active most days, and they are able to work without much supervision. "They exceed my expectations," Lyon said.
And even outside of work the GAs stick together as a team. "A roomful of strangers become the best of friends in four months," Lyon said. In the morning, they trade jokes and stories,
as well as tips and thoughts about previous work or that day’s upcoming projects. At lunch, they rally around each other, asking, "How’s your day going?" and exchanging reports of how life and work are in different departments.
The bottom line for most of the GAs is that they’re here on the Ice and experiencing a range of ways to work and live. "If you’re going to work your butt off for not very much money, why not do it here?" Lyon said.
Sunday, December 24, 2000
Sunday, November 26, 2000
Pinpoint precision: Geographic locators are accurate to within tenths of an inch
Published in the Antarctic Sun
Several scientists in the U.S. Antarctic Program use specific measurements and locations on the surface of the Earth as key elements in their research. They watch many processes, including
the movement of glaciers, growth or shrink rates of ice sheets and rock layers and the melting of patches of snow in the Dry Valleys.
These researchers use the Global Positioning System, originally created for combat use by the U.S. Defense Department, to locate themselves and their study areas very specifically. At McMurdo Station each summer are GPS experts who provide equipment and training for about 20 science groups on the continent.
“We’re supporting grantees who are using GPS for their field research,” said project leader Bjorn Johns, of the University NAVSTAR Consortium (UNAVCO), a group of 100 academic institutions, including the National Science Foundation, promoting the use of high-accuracy GPS for scientific research.
Many people on the Ice and in the U.S. have their own handheld GPS units, which cost around $200. “It’s become a national utility,” Johns said.
Commercial handhelds provide accuracy to within about fifteen feet of an actual location, Johns said. By contrast, the equipment Johns and his colleague Chuck Kurnik issue are accurate to within tenths of an inch, cost around $15,000 and involve a plattersize antenna and laptop computer-size receiving box.
GPS is based on a group of satellites orbiting Earth and several ground stations monitoring them. The satellites broadcast their position in space and the exact time from an on-board atomic
clock. By receiving the signals from several satellites, a GPS unit on the ground can calculate its location.
But that can be difficult at high latitudes because the satellites don’t pass directly overhead, which would give the best possible readings. “They’re all low on the horizon in the polar regions,” Johns said.
All of the positions calculated are relative to other, fixed, known locations. To be precise, measurements need to be compared very carefully with the exact trajectories of the satellites at the time of the reading.
“That typically means collecting and post-processing data,” Johns said. That process can take a couple of days, he said. Some groups need Johns and Kurnik to do GPS portion of their work, while other researchers need technical assistance or data-processing help.
Johns and Kurnik also install both permanent and temporary stationary GPS stations to monitor ongoing geologic processes and to improve accuracy of nearby readings.
This season, they put a station on Mount Erebus to watch how underground activity changes the volcano’s surface. “If there’s any inflation or deflation of the volcano relative to McMurdo we’ll see that,” Johns said. If anything significant happened on Erebus, or anywhere else with a permanent GPS monitoring station, the data would be valuable for scientists.
“When an event occurs, you’ve captured it, with pre- and post-event data,” Johns said.
Another important element is fixing the exact antenna position to the ground. If a measurement is accurate within fractions of an inch, a human error in antenna placement for observation could
appear to be a large fluctuation in surface movement.
To provide a stable platform, Johns and Kurnik sink a metal rod into the rock or ice and affix a leveling platform to the rod. The antenna screws onto the platform.
Each reading, then, is taken from the same location relative to the rod. If a location change is measured, it means the rod has moved, and therefore the rock or ice surrounding the rod has moved.
This type of measurement is possible around the world using base stations and satellite readings anywhere on the surface of the Earth. But Johns said Antarctica is where GPS gets used most heavily. He and Kurnik may support five science projects during the rest of the year, and more than 20 during the summer field season on the Ice.
The GPS work helps influence future research, Johns said. This season at Icestream C, a group wanted to drill an ice core in an area where the glacier isn’t moving very quickly. Because of GPS
surveying last year, they knew where one was.
GPS is also used to map the atmosphere. Since GPS uses radio waves, which behave differently as atmospheric conditions change, GPS readings at known locations can show variations in
the ionosphere and troposphere through changes in radio waves along different paths.
Johns and Kurnik don’t directly interact with the atmospheric mapping projects, which are not based in Antarctica, but help people use GPS in all kinds of ways. “Everyone has something they want measured,” Johns said.
Several scientists in the U.S. Antarctic Program use specific measurements and locations on the surface of the Earth as key elements in their research. They watch many processes, including
the movement of glaciers, growth or shrink rates of ice sheets and rock layers and the melting of patches of snow in the Dry Valleys.
These researchers use the Global Positioning System, originally created for combat use by the U.S. Defense Department, to locate themselves and their study areas very specifically. At McMurdo Station each summer are GPS experts who provide equipment and training for about 20 science groups on the continent.
“We’re supporting grantees who are using GPS for their field research,” said project leader Bjorn Johns, of the University NAVSTAR Consortium (UNAVCO), a group of 100 academic institutions, including the National Science Foundation, promoting the use of high-accuracy GPS for scientific research.
Many people on the Ice and in the U.S. have their own handheld GPS units, which cost around $200. “It’s become a national utility,” Johns said.
Commercial handhelds provide accuracy to within about fifteen feet of an actual location, Johns said. By contrast, the equipment Johns and his colleague Chuck Kurnik issue are accurate to within tenths of an inch, cost around $15,000 and involve a plattersize antenna and laptop computer-size receiving box.
GPS is based on a group of satellites orbiting Earth and several ground stations monitoring them. The satellites broadcast their position in space and the exact time from an on-board atomic
clock. By receiving the signals from several satellites, a GPS unit on the ground can calculate its location.
But that can be difficult at high latitudes because the satellites don’t pass directly overhead, which would give the best possible readings. “They’re all low on the horizon in the polar regions,” Johns said.
All of the positions calculated are relative to other, fixed, known locations. To be precise, measurements need to be compared very carefully with the exact trajectories of the satellites at the time of the reading.
“That typically means collecting and post-processing data,” Johns said. That process can take a couple of days, he said. Some groups need Johns and Kurnik to do GPS portion of their work, while other researchers need technical assistance or data-processing help.
Johns and Kurnik also install both permanent and temporary stationary GPS stations to monitor ongoing geologic processes and to improve accuracy of nearby readings.
This season, they put a station on Mount Erebus to watch how underground activity changes the volcano’s surface. “If there’s any inflation or deflation of the volcano relative to McMurdo we’ll see that,” Johns said. If anything significant happened on Erebus, or anywhere else with a permanent GPS monitoring station, the data would be valuable for scientists.
“When an event occurs, you’ve captured it, with pre- and post-event data,” Johns said.
Another important element is fixing the exact antenna position to the ground. If a measurement is accurate within fractions of an inch, a human error in antenna placement for observation could
appear to be a large fluctuation in surface movement.
To provide a stable platform, Johns and Kurnik sink a metal rod into the rock or ice and affix a leveling platform to the rod. The antenna screws onto the platform.
Each reading, then, is taken from the same location relative to the rod. If a location change is measured, it means the rod has moved, and therefore the rock or ice surrounding the rod has moved.
This type of measurement is possible around the world using base stations and satellite readings anywhere on the surface of the Earth. But Johns said Antarctica is where GPS gets used most heavily. He and Kurnik may support five science projects during the rest of the year, and more than 20 during the summer field season on the Ice.
The GPS work helps influence future research, Johns said. This season at Icestream C, a group wanted to drill an ice core in an area where the glacier isn’t moving very quickly. Because of GPS
surveying last year, they knew where one was.
GPS is also used to map the atmosphere. Since GPS uses radio waves, which behave differently as atmospheric conditions change, GPS readings at known locations can show variations in
the ionosphere and troposphere through changes in radio waves along different paths.
Johns and Kurnik don’t directly interact with the atmospheric mapping projects, which are not based in Antarctica, but help people use GPS in all kinds of ways. “Everyone has something they want measured,” Johns said.
Swedish Polar Ambassador visits Ross Island
Published in the Antarctic Sun
The New Zealand Antarctic Program played host to the Swedish polar ambassador, Eva Kettis, last week.
She had been in Hobart, Tasmania, Australia, for a meeting of the Commission for the Conservation of Antarctic Marine Living Resources and was invited to be a guest at Scott Base.
After several days on weather hold in Christchurch, Kettis arrived on the Ice for her second visit. Her first visit was to a site on the Antarctic Peninsula where a hut was built by an early Swedish Antarctic explorer, Otto Nordenskjold, in 1901.
Sweden, which signed the Antarctic Treaty in 1984, maintains two small summer-only camps in Queen Maud Land and cooperates with Finland and Norway in areas of logistics and operations.
“We have subscribed totally to the Antarctic Treaty goals,” Kettis said.
While she is the ambassador for both polar regions, Kettis said she concentrates most of her
effort on the Arctic. “That’s perhaps nearer to our heart,” Kettis said.
She works with the Arctic Council, a group that includes the eight countries that border the Arctic and several groups of Arctic indigenous people. “That is quite unusual for intergovernmental cooperation,” Kettis said.
The political issues, she said, are very different in the north and south polar regions. For example, since the Arctic is largely ocean, no country can make territorial claims. Research,
on the other hand, is similar in the two areas.
“The science has a clear bipolar aspect,” Kettis said. “I think it has not only polar aspects but global aspects.”
On her trip to the Ice, she visited Ross Island’s historic huts, various field camp locations around the Ross Sea and in the Dry Valleys, and visited McMurdo, where she was particularly
impressed by the mawsonii in the old aquarium.
“I never thought I would see a big toothfish,” Kettis said.
As well, she toured Scott Base and liked what she saw. “They are very well equipped and it
works very well,” Kettis said.
She was unable to leave on schedule because of the weather, which frustrated her a bit, but Kettis said she was glad to be able to see this part of “this huge and beautiful continent.”
The New Zealand Antarctic Program played host to the Swedish polar ambassador, Eva Kettis, last week.
She had been in Hobart, Tasmania, Australia, for a meeting of the Commission for the Conservation of Antarctic Marine Living Resources and was invited to be a guest at Scott Base.
After several days on weather hold in Christchurch, Kettis arrived on the Ice for her second visit. Her first visit was to a site on the Antarctic Peninsula where a hut was built by an early Swedish Antarctic explorer, Otto Nordenskjold, in 1901.
Sweden, which signed the Antarctic Treaty in 1984, maintains two small summer-only camps in Queen Maud Land and cooperates with Finland and Norway in areas of logistics and operations.
“We have subscribed totally to the Antarctic Treaty goals,” Kettis said.
While she is the ambassador for both polar regions, Kettis said she concentrates most of her
effort on the Arctic. “That’s perhaps nearer to our heart,” Kettis said.
She works with the Arctic Council, a group that includes the eight countries that border the Arctic and several groups of Arctic indigenous people. “That is quite unusual for intergovernmental cooperation,” Kettis said.
The political issues, she said, are very different in the north and south polar regions. For example, since the Arctic is largely ocean, no country can make territorial claims. Research,
on the other hand, is similar in the two areas.
“The science has a clear bipolar aspect,” Kettis said. “I think it has not only polar aspects but global aspects.”
On her trip to the Ice, she visited Ross Island’s historic huts, various field camp locations around the Ross Sea and in the Dry Valleys, and visited McMurdo, where she was particularly
impressed by the mawsonii in the old aquarium.
“I never thought I would see a big toothfish,” Kettis said.
As well, she toured Scott Base and liked what she saw. “They are very well equipped and it
works very well,” Kettis said.
She was unable to leave on schedule because of the weather, which frustrated her a bit, but Kettis said she was glad to be able to see this part of “this huge and beautiful continent.”
Sunday, November 19, 2000
Mind is in Maine
Published in the Antarctic Sun
On the windowsill above Ted Dettmar’s desk sits a picture of him taken five years ago. He looks every bit an old-time Down-East farmer of Maine. His ballcap is pulled down over unruly hair, his long red beard hanging over a canvas jacket. His feet are sunk deep into a pair of rubber Wellington gumboots, and he sits atop a piece of farm machinery that has seen better days.
In the picture, Dettmar has one horse reined in very tightly and the other let all the way loose. That’s how he handles his world, letting things go along their own way and then taking charge at specific moments that make all the difference.
Dettmar, 36, grew up in suburban Arlington, Virginia, the youngest of six children in a military family. His family lived all over the world while they were growing up and have all settled near the home their parents retired to, the one in which Dettmar grew up.
It’s Ted who is now wandering the globe, with this picture and a very specific goal.
“I want to live as close to the land as possible,” Dettmar said, “to get to know every tree, every bush, the soil types, the rock types.”
Here in Antarctica, that may seem a very easy dream: No trees, no bushes, no soil. And there’s not all that much rock, either. But he’s talking about New England, and a vividly simple life on a
farm.
Dettmar knows it’s a long way from the Ice, where everything is imported by cargo plane or container ship from the rest of the world, where the landscape can and will kill.
“The irony is not lost on me,” he said.
Now known as one of McMurdo’s eminent historians of the Heroic Age of Antarctic exploration, Dettmar didn’t know much about Antarctica until just a few years ago.
The first thing he read about the Ice was Apsley Cherry-Garrard’s book, The Worst Journey in the World.
“That’s the typical first book,” Dettmar said. Just as he finished that, he came across another book.
“Somebody handed me a copy of Endurance and it had the crew list,” he said. One of the names on that list was Thomas Crean, a name he recognized as having been part of Scott’s Terra Nova
expedition from 1910 to 1913.
“I found out there were these guys who were just indestructible, just made of stone,” Dettmar said. They just kept coming back to Antarctica on expeditions.
When he got to McMurdo as a GA in 1994, he took a tour of the Discovery hut, given by someone who didn’t know what he was talking about.
“The tour guide was abysmal. The guy knew nothing,” Dettmar said. A history major in college, Dettmar bristled.
“People deserve to know more. These are interesting stories,” Dettmar said. “I thought, ‘We need people who can bring these places alive.’ I said, ‘That’s going to be me.’”
After working in waste management and now for the Field Safety Training Program, Dettmar now shares with people not only the history but also the practical lessons learned by polar explorers.
Even so, he doesn’t claim to be following in the footsteps of early explorers like Scott and Amundsen.
“There’s no comparison,” Dettmar said. "Amundsen’s story is the story of what people can accomplish," he said, likening it to the construction of the George Washington Bridge over the
Hudson River.
“Scott’s and Shackleton’s stories are the story of what humans can endure,” he said. “Everything they did was a close call.”
That’s not how Dettmar likes to do things, though some might disagree.
“I do not consider myself to be adventurous in the least,” he said.
He has been doing search-and-rescue since his junior year in college, recovering light aircraft crashed in the Shenandoah Mountains of Virginia, and lived for five winters in the Harvard Cabin in Huntington Ravine on New Hampshire’s Mount Washington.
With that experience, Dettmar got out into the deep field quite a bit as a GA, and was a rare first-year selection for the secondary SAR team. He’s been on the primary SAR team since his second year.
Now he’s the lead field safety instructor, in training his coworkers to do their jobs as best they can. He still takes the lead in sea ice training, which is his specialty, and keeps watch while
the rest of the instructors teach and learn and do.
“I think I can do it as long as I’ve got people underneath me who are more qualified than I am,” Dettmar said.
As much as the job, he really likes being here and being part of history.
When he leaves for the last time, he said, he expects he’ll be bawling. “I’m always ready to come back down here.”
On the windowsill above Ted Dettmar’s desk sits a picture of him taken five years ago. He looks every bit an old-time Down-East farmer of Maine. His ballcap is pulled down over unruly hair, his long red beard hanging over a canvas jacket. His feet are sunk deep into a pair of rubber Wellington gumboots, and he sits atop a piece of farm machinery that has seen better days.
In the picture, Dettmar has one horse reined in very tightly and the other let all the way loose. That’s how he handles his world, letting things go along their own way and then taking charge at specific moments that make all the difference.
Dettmar, 36, grew up in suburban Arlington, Virginia, the youngest of six children in a military family. His family lived all over the world while they were growing up and have all settled near the home their parents retired to, the one in which Dettmar grew up.
It’s Ted who is now wandering the globe, with this picture and a very specific goal.
“I want to live as close to the land as possible,” Dettmar said, “to get to know every tree, every bush, the soil types, the rock types.”
Here in Antarctica, that may seem a very easy dream: No trees, no bushes, no soil. And there’s not all that much rock, either. But he’s talking about New England, and a vividly simple life on a
farm.
Dettmar knows it’s a long way from the Ice, where everything is imported by cargo plane or container ship from the rest of the world, where the landscape can and will kill.
“The irony is not lost on me,” he said.
Now known as one of McMurdo’s eminent historians of the Heroic Age of Antarctic exploration, Dettmar didn’t know much about Antarctica until just a few years ago.
The first thing he read about the Ice was Apsley Cherry-Garrard’s book, The Worst Journey in the World.
“That’s the typical first book,” Dettmar said. Just as he finished that, he came across another book.
“Somebody handed me a copy of Endurance and it had the crew list,” he said. One of the names on that list was Thomas Crean, a name he recognized as having been part of Scott’s Terra Nova
expedition from 1910 to 1913.
“I found out there were these guys who were just indestructible, just made of stone,” Dettmar said. They just kept coming back to Antarctica on expeditions.
When he got to McMurdo as a GA in 1994, he took a tour of the Discovery hut, given by someone who didn’t know what he was talking about.
“The tour guide was abysmal. The guy knew nothing,” Dettmar said. A history major in college, Dettmar bristled.
“People deserve to know more. These are interesting stories,” Dettmar said. “I thought, ‘We need people who can bring these places alive.’ I said, ‘That’s going to be me.’”
After working in waste management and now for the Field Safety Training Program, Dettmar now shares with people not only the history but also the practical lessons learned by polar explorers.
Even so, he doesn’t claim to be following in the footsteps of early explorers like Scott and Amundsen.
“There’s no comparison,” Dettmar said. "Amundsen’s story is the story of what people can accomplish," he said, likening it to the construction of the George Washington Bridge over the
Hudson River.
“Scott’s and Shackleton’s stories are the story of what humans can endure,” he said. “Everything they did was a close call.”
That’s not how Dettmar likes to do things, though some might disagree.
“I do not consider myself to be adventurous in the least,” he said.
He has been doing search-and-rescue since his junior year in college, recovering light aircraft crashed in the Shenandoah Mountains of Virginia, and lived for five winters in the Harvard Cabin in Huntington Ravine on New Hampshire’s Mount Washington.
With that experience, Dettmar got out into the deep field quite a bit as a GA, and was a rare first-year selection for the secondary SAR team. He’s been on the primary SAR team since his second year.
Now he’s the lead field safety instructor, in training his coworkers to do their jobs as best they can. He still takes the lead in sea ice training, which is his specialty, and keeps watch while
the rest of the instructors teach and learn and do.
“I think I can do it as long as I’ve got people underneath me who are more qualified than I am,” Dettmar said.
As much as the job, he really likes being here and being part of history.
When he leaves for the last time, he said, he expects he’ll be bawling. “I’m always ready to come back down here.”
Diving for science
Published in the Antarctic Sun
Most scientists in the U.S. Antarctic Program study things on or above the ground. Some even explore the sky or faraway galaxies. But a select few regularly descend into Antarctic waters to collect material and information for their research.
On average, 20 divers make 600 dives a year in McMurdo Sound, the Dry Valleys, near Palmer Station and based from the program’s two research vessels, said scientific diving coordinator Rob Robbins.
The highest number of dives recorded in any one year was 908 in 1984, Robbins said. The average dive lasts 40 minutes, though some have gone longer than 90 minutes. The water in McMurdo Sound is 28.5 F (-2C), and near Palmer it’s only slightly warmer, at
30 F (-1C).
This summer season, six research groups, five based at McMurdo and one at Palmer, will include16 divers. The GLOBEC survey of the Southern Ocean ecosystem, based on the Laurence M. Gould and Nathaniel B. Palmer research vessels, will have two groups diving in March.
Less commonly, Robbins will dive to support specific projects that don’t have their own divers.
“Most groups bring down whatever dive labor they require,” Robbins said.
Scientists dive for many reasons, including photographing marine life, collecting specimens for lab work and maintaining underwater equipment.
“The facilities here are fabulous for diving,” said John Heine, the U.S. Antarctic Program’s advisor for research diving. “The diving conditions are really great. The support from Rob is really what makes it happen.”
One reason to dive in McMurdo Sound is that the low water temperature attracts deepsea wildlife to shallow water with little light filtering through the sea ice.
“The sound is fairly interesting,” Robbins said. “You see animals in the sound you would normally see in deep water, but at diveable depths.”
The depth at which wildlife are observable is important, because diving deeper than 130 feet and for extended periods is not allowed for scientific research. Deep diving is more complex and dangerous, even in warmer waters. In Antarctica, the margin of error is slimmer, so divers take more precautions.
“ We don’t allow decompression diving,” Robbins said.
That’s when a diver needs to pause on the way back up to the surface to adjust to the difference
in pressure.
McMurdo Station has a recompression chamber, originally installed in 1984 to comply with federal safety regulations for construction diving. After the construction finished, Robbins
said, station management decided to keep the chamber in case of dive accidents.
Since then, nine people have needed treatment. Four were aviators who had decompression
problems after accidents in which their airplanes depressurized at altitude. The other five patients were divers.
“Every one was a complete resolution,” Robbins said.
Robbins runs the recompression chamber with a volunteer crew of six, as well as a doctor
and a medical technician from the medical department on station.
Palmer Station has no chamber, though there is one at the nearby British base, Rothera, as well as in Punta Arenas, Chile.
Robbins works hard, though, to avoid accidents, and gives each dive group a firstaid kit and an oxygen kit.
“ We provide a lot of safety equipment,” he said.
He also ensures that science divers know how to move around underwater while wearing a dry suit, which keeps them warmer than a wetsuit would.
“It’s really the dry suit that’s different from most diving,” Robbins said.
A dry suit traps a lot more air than a standard buoyancy control device. Therefore, as
the divers change depth, their buoyancy changes rapidly.
Each season, each diver has to do a refresher or orientation dive to qualify for Antarctic diving, because some of the things are different here. For example, most underice diving courses teach divers to use tethers.
But here, the water is so clear, Robbins said, that they don’t need tethers if they appropriately
mark the holes.
“Here the visibility’s good. When visibility drops we use the tethers,” Robbins said.
There are two ways to breathe under water. If divers use scuba tanks, at least two divers must be in the water, to help each other in the event of an accident.
When a diver is breathing from a surface supply of air, the system not only permits twoway
communication between the diver and someone on the surface, but a rescuer can follow the air hose from the surface to a diver in distress. So a standby diver is still present, suited up and ready to swim, but is on the surface.
With only one diver using air at a time, they can take turns diving and being the standby diver for each other, accomplishing more in one outing.
“ You can do a lot more work,” Robbins said.
Also with surface supply, a diver is more comfortable in the water, Robbins said.
“It’s quite a bit warmer,” he said. “Your face is covered.”
Robbins said he would like to be doing more commercial construction diving, but he’s pretty happy with the science support end of things as well.
“This is a lot more scenic,” he said. “I’ve potentially got the best job in the program.”
Most scientists in the U.S. Antarctic Program study things on or above the ground. Some even explore the sky or faraway galaxies. But a select few regularly descend into Antarctic waters to collect material and information for their research.
On average, 20 divers make 600 dives a year in McMurdo Sound, the Dry Valleys, near Palmer Station and based from the program’s two research vessels, said scientific diving coordinator Rob Robbins.
The highest number of dives recorded in any one year was 908 in 1984, Robbins said. The average dive lasts 40 minutes, though some have gone longer than 90 minutes. The water in McMurdo Sound is 28.5 F (-2C), and near Palmer it’s only slightly warmer, at
30 F (-1C).
This summer season, six research groups, five based at McMurdo and one at Palmer, will include16 divers. The GLOBEC survey of the Southern Ocean ecosystem, based on the Laurence M. Gould and Nathaniel B. Palmer research vessels, will have two groups diving in March.
Less commonly, Robbins will dive to support specific projects that don’t have their own divers.
“Most groups bring down whatever dive labor they require,” Robbins said.
Scientists dive for many reasons, including photographing marine life, collecting specimens for lab work and maintaining underwater equipment.
“The facilities here are fabulous for diving,” said John Heine, the U.S. Antarctic Program’s advisor for research diving. “The diving conditions are really great. The support from Rob is really what makes it happen.”
One reason to dive in McMurdo Sound is that the low water temperature attracts deepsea wildlife to shallow water with little light filtering through the sea ice.
“The sound is fairly interesting,” Robbins said. “You see animals in the sound you would normally see in deep water, but at diveable depths.”
The depth at which wildlife are observable is important, because diving deeper than 130 feet and for extended periods is not allowed for scientific research. Deep diving is more complex and dangerous, even in warmer waters. In Antarctica, the margin of error is slimmer, so divers take more precautions.
“ We don’t allow decompression diving,” Robbins said.
That’s when a diver needs to pause on the way back up to the surface to adjust to the difference
in pressure.
McMurdo Station has a recompression chamber, originally installed in 1984 to comply with federal safety regulations for construction diving. After the construction finished, Robbins
said, station management decided to keep the chamber in case of dive accidents.
Since then, nine people have needed treatment. Four were aviators who had decompression
problems after accidents in which their airplanes depressurized at altitude. The other five patients were divers.
“Every one was a complete resolution,” Robbins said.
Robbins runs the recompression chamber with a volunteer crew of six, as well as a doctor
and a medical technician from the medical department on station.
Palmer Station has no chamber, though there is one at the nearby British base, Rothera, as well as in Punta Arenas, Chile.
Robbins works hard, though, to avoid accidents, and gives each dive group a firstaid kit and an oxygen kit.
“ We provide a lot of safety equipment,” he said.
He also ensures that science divers know how to move around underwater while wearing a dry suit, which keeps them warmer than a wetsuit would.
“It’s really the dry suit that’s different from most diving,” Robbins said.
A dry suit traps a lot more air than a standard buoyancy control device. Therefore, as
the divers change depth, their buoyancy changes rapidly.
Each season, each diver has to do a refresher or orientation dive to qualify for Antarctic diving, because some of the things are different here. For example, most underice diving courses teach divers to use tethers.
But here, the water is so clear, Robbins said, that they don’t need tethers if they appropriately
mark the holes.
“Here the visibility’s good. When visibility drops we use the tethers,” Robbins said.
There are two ways to breathe under water. If divers use scuba tanks, at least two divers must be in the water, to help each other in the event of an accident.
When a diver is breathing from a surface supply of air, the system not only permits twoway
communication between the diver and someone on the surface, but a rescuer can follow the air hose from the surface to a diver in distress. So a standby diver is still present, suited up and ready to swim, but is on the surface.
With only one diver using air at a time, they can take turns diving and being the standby diver for each other, accomplishing more in one outing.
“ You can do a lot more work,” Robbins said.
Also with surface supply, a diver is more comfortable in the water, Robbins said.
“It’s quite a bit warmer,” he said. “Your face is covered.”
Robbins said he would like to be doing more commercial construction diving, but he’s pretty happy with the science support end of things as well.
“This is a lot more scenic,” he said. “I’ve potentially got the best job in the program.”
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