Published in the Antarctic Sun
MacOps bills itself as the Voice of Antarctica. The radio operators there talk to people all over the continent and elsewhere around the world on high-frequency and very high-frequency radios.
Thursday, just before lunch, the continent got a sore throat.
All the HF radios went quiet, broadcasting white noise instead of voices from all over.
“It was pretty eerie,” said Paula Elliott of MacRelay, which also monitors all radio frequencies.
A solar flare had sent a mass of charged particles out from the sun into the Earth’s atmosphere. Those charged particles had disrupted the ionosphere, the layer of Earth’s atmosphere that
reflects HF radio waves, preventing transmission of HF waves around the globe.
The radiation, the fourth largest storm of its type since 1976, caused some rearrangement
of communications and transport schedules on the continent.
“Camps were unable to check in,” Elliott said. “People were technically overdue for their
check-ins, though we knew why.”
If camps miss their check-ins under normal circumstances, rescue missions are launched. This
time, though, radio operators waited and worked around the situation.
They had lost contact with South Pole Station, Byrd Surface Camp, Siple Dome, Byrd Glacier, as well as the Olympus Range and Lake Vida, which are in VHF “dead spots” in the Dry Valleys.
Communications with the Pole were possible on the Internet during the Pole’s satellite window. The people at Vida had to climb a hill to hit a VHF repeater.
“We didn’t expect it to be as big as it was,” said MacOps coordinator Shelly DeNike.
The camp at Icestream C was put in during the communications blackout.
Normally, an airplane can’t leave a camp put-in until the camp radios MacOps on HF. This time, though, the camp was only able to talk to the plane on the ground. The solar flare’s energy prevented them from talking farther away.
Other than that small glitch, everything was fine.
“We’ve been pretty much prepared for this to happen,” DeNike said.
The larger field camps have emergency beacons they can set off if all else fails, just like if an aircraft crashes or a boat is in distress at sea. Had anything truly disastrous happened, they could have activated the beacon.
After two days without contact from Byrd Surface Camp, an airplane went out of its way to fly over it to make contact. Pilots helped by contacting camps along their flight routes.
“When they would fly in the vicinity of field camps they would call them,” DeNike
said.
Camp managers knew this might be a problem. Before going into the field, they had been briefed that HF problems might occur in this year of high solar activity.
In terms of air traffic control, everything also went smoothly with what air traffic manager Dusty Barrett called “a little bit of creative scheduling.”
Before planes left McMurdo, controllers gave pilots instructions for flying both to and from the Pole; normally they clear flights for only one direction at a time. MacCenter, the hub of air traffic control at McMurdo was only able to talk to the planes while they were within line-of-sight.
In a contingency set up last year, they had two controllers in Christchurch, New Zealand.
The controllers in McMurdo talked over the phone to Christchurch, which relayed messages over a satellite communication link to the planes.
“Once the HF went down we had to be a little bit creative,” Barrett said.
They also used Iridium satellite phones, Barrett said. Pilots continued to use HF, sending their position reports “in the blind,” without knowing if they were received, in the hope that MacCenter could hear them.
“Sometimes you can receive but you can’t transmit,” Barrett said.
This is the second full blackout since Winfly, but there have been partial blackouts where only lower frequencies were cut off.
This type of event has happened in the past, but only for 24 to 48 hours, Elliott said. This time it was Saturday evening before things came back, a shutdown of nearly 60 hours.
“We’ve seen a lot more activity than we had last year,” Elliott said.
It may have to do with a peak in the 11-year cycle of solar activity. Sometimes these effects from flares are predictable, and this time there was some warning. But the loss of HF communications was rapid.
“It happened right away,” DeNike said.
Things are back to normal now, Elliott said, but it could happen again anytime, and without a lot of warning.
“They hit without much notice,” she said.
Sunday, November 19, 2000
Exploring the plateau
Published in the Antarctic Sun
The U.S. segment of the International Trans-Antarctic Scientific Expedition left Thursday for Byrd Surface Camp to begin this season’s traverse of the West Antarctic ice sheet.
The project is a multi-national effort in which the U.S. component this year involves 10 research institutions and five areas of study: meteorology, surface glaciology, geophysics, remote sensing and ice coring.
“It’s five coordinated disciplines,” said Paul Mayewski, coordinator of the U.S. traverse group.
Last year was the first of this four-year project that will end at the Pole in 2003. The information the team collected last year is already helping improve scientists’ understanding of the world’s climate.
The data is specific to the region of West Antarctica where the traverse will occur, but it shows effects of regional and even global weather and climate systems.
“What we’re looking for isn’t just an understanding of Antarctica,” Mayewski said.
By looking at snow layers in Antarctica ice sheets revealing the last 200 to 500 years of the Earth’s climatic history, ITASE groups across the continent have already learned about the
relationship of certain Antarctic weather patterns to large-scale climate phenomena like El Niño.
“We already have seen some very interesting results,” Mayewski said.
The team is also comparing the results from their work in the Antarctic to similar work in the North Atlantic, another powerful element in the engine of Earth’s weather. While small changes are localized, Mayewski said, larger alterations are visible in ice cores from both ends of the globe.
This field season, the traverse team will cover 1,200 kilometers in a triangular path starting and ending at Byrd Surface Camp. During the drive, they will use downward-looking radar to map the strata in the ice beneath the route. They will also have a shorter range crevasse detector radar unit operating to keep the vehicles and researchers safe out on the plateau.
At roughly 100-kilometer intervals, they will stop for a few days to drill a 200-meter ice core. The core itself and the hole it leaves show the chemical and physical properties of the layers of
snow.
They will identify specific layers in the cores that can be cross-referenced to the radar data, allowing them to follow snow layers for hundreds of miles.
“It’s almost like a three-dimensional ice core,” Mayewski said.
The data they get from the cores and from the radar shows indicators of the extent of the sea ice, activity of marine life and duration of polar stratospheric clouds in recent centuries, Mayewski said.
This year the team will be able to haul more equipment and better shelters, because they have a Challenger instead of one of the two Tucker Sno-Cats they used last year. The other Sno-Cat will
continue the journey this season.
As the project progresses, Mayewski said, the setup and takedown at either end of the traverse will become more streamlined, as vehicles and supplies are left to spend the winter on the plateau.
“We should be able to go in with a very small amount of C-130 support,” Mayewski said. This is a big efficiency advantage, he said, as compared with individual field camps.
“There are 10 institutions that can potentially be served by two to three flights in and two to three flights out,” Mayewski said, adding that fuel airdrops will also be part of the support of
the field traverses. This year they expect to use seven flights in and four flights out.
To choose its exact route, the team uses satellite photos to avoid crevassed areas and other potentially problematic sites. But they also confirm satellite pictures by reporting on surface conditions and comparing that information to the pictures taken from space.
In addition to their own work and contributions to wider projects like the International Geosphere and Biosphere Project, one of this year’s shallow cores is at a possible deep-core site like the one at Siple Dome.
“This is a return of the 1960s style of science in this region, with 21st century technology,” Mayewski said.
The U.S. segment of the International Trans-Antarctic Scientific Expedition left Thursday for Byrd Surface Camp to begin this season’s traverse of the West Antarctic ice sheet.
The project is a multi-national effort in which the U.S. component this year involves 10 research institutions and five areas of study: meteorology, surface glaciology, geophysics, remote sensing and ice coring.
“It’s five coordinated disciplines,” said Paul Mayewski, coordinator of the U.S. traverse group.
Last year was the first of this four-year project that will end at the Pole in 2003. The information the team collected last year is already helping improve scientists’ understanding of the world’s climate.
The data is specific to the region of West Antarctica where the traverse will occur, but it shows effects of regional and even global weather and climate systems.
“What we’re looking for isn’t just an understanding of Antarctica,” Mayewski said.
By looking at snow layers in Antarctica ice sheets revealing the last 200 to 500 years of the Earth’s climatic history, ITASE groups across the continent have already learned about the
relationship of certain Antarctic weather patterns to large-scale climate phenomena like El Niño.
“We already have seen some very interesting results,” Mayewski said.
The team is also comparing the results from their work in the Antarctic to similar work in the North Atlantic, another powerful element in the engine of Earth’s weather. While small changes are localized, Mayewski said, larger alterations are visible in ice cores from both ends of the globe.
This field season, the traverse team will cover 1,200 kilometers in a triangular path starting and ending at Byrd Surface Camp. During the drive, they will use downward-looking radar to map the strata in the ice beneath the route. They will also have a shorter range crevasse detector radar unit operating to keep the vehicles and researchers safe out on the plateau.
At roughly 100-kilometer intervals, they will stop for a few days to drill a 200-meter ice core. The core itself and the hole it leaves show the chemical and physical properties of the layers of
snow.
They will identify specific layers in the cores that can be cross-referenced to the radar data, allowing them to follow snow layers for hundreds of miles.
“It’s almost like a three-dimensional ice core,” Mayewski said.
The data they get from the cores and from the radar shows indicators of the extent of the sea ice, activity of marine life and duration of polar stratospheric clouds in recent centuries, Mayewski said.
This year the team will be able to haul more equipment and better shelters, because they have a Challenger instead of one of the two Tucker Sno-Cats they used last year. The other Sno-Cat will
continue the journey this season.
As the project progresses, Mayewski said, the setup and takedown at either end of the traverse will become more streamlined, as vehicles and supplies are left to spend the winter on the plateau.
“We should be able to go in with a very small amount of C-130 support,” Mayewski said. This is a big efficiency advantage, he said, as compared with individual field camps.
“There are 10 institutions that can potentially be served by two to three flights in and two to three flights out,” Mayewski said, adding that fuel airdrops will also be part of the support of
the field traverses. This year they expect to use seven flights in and four flights out.
To choose its exact route, the team uses satellite photos to avoid crevassed areas and other potentially problematic sites. But they also confirm satellite pictures by reporting on surface conditions and comparing that information to the pictures taken from space.
In addition to their own work and contributions to wider projects like the International Geosphere and Biosphere Project, one of this year’s shallow cores is at a possible deep-core site like the one at Siple Dome.
“This is a return of the 1960s style of science in this region, with 21st century technology,” Mayewski said.
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