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Hi Again from the Scar Inlet Camp

February 23, 2016

Ted Scambos writes:

In the first two weeks out here, we’ve set up an array of measurement instruments to observe how the ocean ice (‘fast’ ice near the coast) and the much thicker ice shelf ice behave at the end of the summer. In past years, this has been the time of year when major changes, and even ice shelf collapse, have occurred. The weather has turned cooler, and it is unlikely the ice will break out this year, but the instrumentation we have brought, and the long steady data acquisition we’ve had since we set up the instruments, has yielded some interesting results.

One of the main instruments we set out are time-lapse cameras. The idea here is of course to detect changes in the ice fracture patterns, and any movement of the icebergs that are the breaking away from the ice shelf. We have set out six camera systems, as two stereo pairs (for 3-D data) and as ‘eagle eye’ systems looking at the most active features. The pre-installed AMIGOS-6 system has been watching the area 4 times a day for the past 4 years, but we’ve set up much faster systems now to catch a movie-like view of the changes, with 2-minute repeats of each scene. Sure enough, during some wind-storms we’ve seen the fast ice fractures move a bit, straining as many square miles of rough ocean ice surface are pushed by the wind. Satellite pictures tell us that the biggest wind-storm (gusts to ~40 kts, or around 20 m/sec) pushed the loose sea ice to the east of us about 3 kilometers… but the fast ice here held.
pippas_point_cameras

Time-lapse cameras watch the fast ice, icebergs, and ice shelf junction area from the outcrop we call ‘Pippa’s Point’. The cameras have been taking pictures every two minutes for ~15 days.

We have a more sensitive way of looking at ice motion: a radar system. This radar array (the Gamma Portable Radar Interferometer, or GPRI) collects data sets that can be very sensitively differenced from one another, to detect even millimeters of movement. This is the instrument we anticipate will tell us the most about the state of the ice in this area, and may provide clues as to how much the fast ice is buttressing the ice shelf and inhibiting its break-up (or ‘calving’ in glaciology terms). We may see a tidal signal of ice movement and fracture, and it appears that we’ve captured smaller versions of the ice shelf collapse process in some of the icebergs close to the system. The team has worked extremely hard to keep this high-tech instrument going in the conditions of a deep field tent camp, but it has paid off in several terabytes of data. Early processing here in the field shows that we’ve captured the movement of the ice well, and have data extending out to about 8 km.

amigos_point_gpri

Chris Carr and ‘Chucky’ Stevens assemble the radar interferometer at ‘AMIGOS Point’.

radar_array

Chris adjusts the data cable for the radar array.

A much simpler ‘radar’ system, really more of a radio-echo sounder, was used to map the ice thickness over the cape. It looks like our cape is actually an island: the neck of ice that extends out from the main coastline appears to rest on rock that is below sea level. If the area were to melt away completely, this would change the local currents.
radio_echo_sounder

The radio-echo-sounder measured a profile of the the ice thickness at Cape Disappointment.

Other sensors aim to use sound and vibration as an indicator of processes going on in the area. We set up an array of special very-low-frequency microphones (an ‘infra-sound array’) on one outcrop of rock to listen to the deep sounds of cracking and grinding going on in the ice – like the deeper notes of thunder, these can travel many miles. The network of microphones allows us to locate the source of the sounds. The majority will come from the shifting sea ice blocks, but a few will likely come from the large ice shelf bergs. We’ve also paired this through-the-air vibration measurement system with three wide-spectrum seismometers to record the larger vibrations as they travel through the earth.
infrasound_array

Dr. Erin Pettit adjusts the the infrasound array. Thin orange cables go out to several microphones located 10 to 100 meters away. The orange box on the left is a seismometer.

We are even listening to the water. After some careful scouting, our field guide found a path where we could safely approach the water’s edge several hundred feet below our field camp and install a hydrophone. This required a technical climb down a steep crumbling slope (which we’ve dubbed ‘Chucky’s Challenge’ after our intrepid BAS field guide). But this too paid off with several 2-minute data ‘takes’ of the ocean sonic environment. Erin put some of the data on a small speaker one evening after our dinner. It was haunting – booms and bangs and strange squeaks, and a constant background hum of tiny bubbles popping as the ice slowly melts.

chuckys_challenge

Christina Carr (blue jacket) helps with the ropes as Chucky Stevens lowers himself to the ice-covered water. A small crack near the shoreline allowed us to place a hydrophone into the ocean.

We brought one more instrument with us that was intended to be used if a truly spectacular break-up were in progress – a camera system mounted onto a tethered helium-filled balloon (or ‘aerostat’). With a set of tiny cameras looking in all directions, the balloon can provide a continuous panorama of events in the ice for up to 24 hours. We decided to test the system for just a few hours one evening, and learn more about how to manage it for other projects.

balloon_deployment

Set-up for the balloon deployment. Left, Erin indicates the expected direction of the flight. Right,Ted completes the set-up of the camera system just before deployment.

balloon_images

Images from Camera 1 on the balloon system. A hand-held GPS is mounted to the payload to record time and elevation during the flight (and records the latitude and longitude internally). Top left, image from ~25 feet above the surface (1013 feet above sea level), showing Erin and Ted, with Chucky at the balloon winch. Top right, image of our camp from approximately 180 feet above. Lower left, a picture of ‘Pippa’s Point (left outcrop) and ‘AMIGOS Point’ (right outcrop) from an elevation of 1000 feet above camp. Lower right, an image of some of the outcrops north of our camp from an altitude of 4674 feet above sea level.

Our work now is mostly managing our instruments, making sure the data acquired are good, and creating back-up copies of what we collect. Soon we will begin to pack up the gear and begin our return to Rothera and then South America. We are now the very last science team still out in the field in the British Antarctic Survey network… and it is getting dark every night. It is time to leave, before the Antarctic winter takes hold.

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Rothera to Cape Disappointment

February 13, 2016

Ted Scambos writes:
On February 3rd, we departed Rothera on a BAS Twin Otter and flew 250 miles northeast to our field site at Cape Disappointment – a near-perfect vantage point to watch how this region might evolve during this warmer-than-average late summer period. The camp is set near the summit of a small dome of rock and ice (about 2 miles across and 1000 feet elevation) set at the end of a narrow low peninsula jutting out into the Larsen B embayment. To the north is a vast flat frozen ocean where the Larsen B ice shelf used to be – now filled with 4-year-old thick ocean ice and tiny iceberg fragments from the collapsing glaciers that formerly fed a 700-foot-thick ice shelf. To the south we can see the smaller remnant ice shelf filling Scar Inlet – among the northernmost remaining ice shelves on the continent, and poised now to collapse or break apart sometime in the next few austral summers. Perhaps this one.

As I write this, we’ve been here for 6 days now, with weather alternating between intense burning sunshine and blinding windstorms. Both conditions are key parts of setting the stage for a breakout of  the frozen ocean or collapse of the ice shelf. During our good weather windows, we set up camp and installed 7 instrument sites — a radar, several stereo camera pairs, seismometers, and  a listening device called an ‘infrasound array’.

scar_melange

A view of the frozen ocean surface and the Scar Inlet ice shelf surface in the distance. Blue patches on the ocean ice are meltwater. Tracking the evolution of the several cracks seen in the middle foreground is a key part of our study.
cape_dis_summit_tent

One of our tents at the summit of Cape Disappointment. Looking north, we can see a nearly flooded ocean ice surface and some distant islands.

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Punta Arenas to Rothera

February 13, 2016

Ted Scambos writes:

The Scar Inlet team spent 3 days in Punta Arenas, Chile completing some packing and checking of items, and then departed for Rothera Station (at the southern tip of Adelaide Island just off the west coast of the Antarctic Peninsula) early on Jan 26th, aboard the British Antarctic Survey Dash-7. The plane is configured as a half passenger, half cargo aircraft, and our hand-carry science gear flew in the front half of the cabin strapped to the floor. With us on the flight were some VIPs visiting the British base – Dr. Jane Francis, director of BAS, Sir Mark Walport, the chief science advisor to the UK government, Tim Stockings, the chief of operations of BAS, and Nick Folland, advisor to NERC (the UK’s environmental research funding agency). We chatted with them about our project and BAS’s role in it – and our great appreciation of BAS’s efficiency and support.

dash-7

The BAS Dash-7, used for transporting passengers and light cargo to Rothera, and for staging of large field projects on smooth ice runway areas on the continent.

The flight was fantastic, a trip over rarely visited parts of the southernmost tip of South America and then out over the Drake Passage and the roughest ocean in the world. Four hours later we caught our first glimpse of the Antarctic Peninsula – a jagged land of black rocks struggling to emerge from a thick mass of ice. Stark but eternally beautiful, and almost always wreathed in clouds or blowing snow.

Our visit to the base was all about preparation: repacking, re-wiring, and testing sensors; and planning and organizing cargo into prioritized loads for the smaller field plane, the Twin Otter. These planes are truly amazing, able to land or take off in as little as 100 yards of smooth snow. We also went to ‘school’ – or in BAS terms, ‘Field Modules 1 to 4’: field camping, ropes and crevasse rescue, motorized snow transport, and field medical training.
tucker_snow_cat

The Rothera ‘Tucker Snow Cat’ vehicle during our ride back from the field camp training area. Rothera Station is just over and below the rocky ridge on the left.

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The Current Team

February 13, 2016

Ted Scambos writes:

Meet the field team for the Scar Inlet survey project: Dr.Erin Pettit is the Principal Investigator,an associate professor from University of Alaska, Fairbanks (UAF); her graduate student, also from UAF, is Christina Carr. Dr. Ted Scambos is the Lead Scientist at National Snow and Ice Data Center (NSIDC) at the University of Colorado at Boulder, and is the Co-PI for this project. In Antarctica we met our fourth team member, Phil ‘Chucky’ Stevens, a British Antarctic Survey (BAS) mountaineering expert and Field Guide.

current_team
Scar Inlet field team – clockwise from upper left: Dr. Erin Pettit aboard the Dash-7; Dr. Ted Scambos at camp on Cape Disappointment, reading texts on the Denver Bronco’s Super Bowl win; Chucky Stevens digging into a bag of re-hydrated ‘man food’ (now for women, too!) – seen with Dr. Pippa Whitehouse of Durham University (visiting our camp for another project) and Erin; Christina Carr arriving at Rothera Station, and jumping onto the boot wash pad, a pad of sterilizing fluid to limit the number of non-Antarctic species brought to the continent.

 

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We’re back!

January 28, 2016

Ted Scambos writes:

The OTI research team has two projects for the 2016 season: a return to the Antarctic Peninsula where a large plate of ice is on the brink of collapse, and testing of a new instrument on a frozen Minnesota lake. The instrument (an ‘AMIGOS-II’, upgraded from the devices already operating in Antarctica) is designed to make combined measurements of weather, ice conditions, and ocean currents and temperature from atop an ice shelf or sea ice. The Antarctic field work is first, and then we’ll shift over to track the instrument expedition in February.

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El Día de Sardinas

February 24, 2014

Rob writers:

Cape Marsh, Robinson Island, Antarctic Peninsula… the last place I’d imagine we’d be eating a can of sardines… Yet here we are, hunkered down in the breeze, having a Sunday Brunch of sardines and biscuits.

Our day started with the usual – obsessively checking the weather via the Antarctic Mesoscale Prediction System (AMPS) and looking at imagery and data from the three AMIGOS towers located to the south of us. Scheduled to be on the helo ramp at 0830, we finally lift off at 0925 – a total of sixteen crew and passengers bound for Cape Marsh and Matienzo station.

On the Helo Pad Waiting for Our rRde

Ted and Terry on the Helo Pad Waiting for Their Ride

Terry on Board the  Helo 94

Terry on Board the Helo 94

Rob and the Base Commander, Gabriel, on Board Helo 94

Rob and the Base Commander, Gabriel, on Board Helo 94

Ted Enjoys the Inflight Beverage Service

Ted Enjoys the Inflight Beverage Service

The flight south from Base Marambio takes about an hour – we circle to land on a rocky spot above the GPS station – touch down and out the door we go – three Norte Americanos and their five boxes of tools, parts, rations and survival gear. Though we’re only planning to be here for an hour and a half, we are prepared to stay at least five days should the weather change or helicopter issues arise.

The helo chatters off with thirteen souls bound for Matienzo Station – the Base Commander at Marambio has chosen a few people among his staff to fly to Matienzo and check on how the station faired through the long winter.

Helo Departing after Dropping Us Off at Cape Marsh

Helo Departing after Dropping Us Off at Cape Marsh

Since we’re on a tight schedule, we get right to work, photographing the GPS installation and documenting any wear and tear by the relentless wind and snow. Ted’s on the satellite phone checking in with Thomas back in Boulder, while Terry and I start digging a trench for the new antenna cable. Time flies as we work to bring the ailing station back to life. One last call to Thomas and UNAVCO confirms that we have a fully operating system – time to pack our gear and get ready for the helo arrival.

The GPS Antenna at Cape Marsh, Robertson Island

The GPS Antenna at Cape Marsh, Robertson Island

“We need to eat these sardines now!” Ted proclaims as we’re closing up our cargo boxes. These damn sardines have been an obsession with him and he will not be denied. We each gulp down an oily sardine, knowing that we’ll have to live with the aftertaste for the next hour’s helo flight. Mission accomplished and we head for home base.

Our Ride Home

Our Ride Home

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Cable Guys – Foyn Point

February 20, 2014

Ted writes:

February 17 dawned clear and warm — an incredible third day in a row of good flying weather, and we were up next. We rolled out of our bunks at 6 am, checked the weather from the AMIGOS stations we installed to the south of our target at Foyn Point — the camera system at Cape Disappointment.  It too was clear, with a few high clouds. Lift-off was set for 8, and we actually left the ground at 8:05.

The helicopters, Russian-built Mi-17 ‘Hip’ models are big, although slightly less big than I initially thought – about the same as the Argentine Navy (Armada) Sea King helicopters. But they are far easier to work with. A large loading ramp opens in the back and the interior is big and boxy. In our case, there was a bit less space because two large interior fuel tanks had been moved inside — with these, the range radius of the Mi-17 is truly incredible, over 200 miles. We were traveling about 140 miles from Marambio. In addition to the three of us (Ted, Terry, and Rob) there were six others in the aircraft. It was still mostly empty. Properly configured for a shorter flight, I think it could hold 20 people.

Helo at Marambio Base

Helo at Marambio Base

Inside Mi-17

Inside Mi-17

We lifted slowly and moved west over the barren dirt of Seymour Island and across a berg- and sea ice dotted ocean towards James Ross Island. I think of this island as the ‘ice cream island’ – a mesa of brown rock topped by a soft white ice cap that is flowing over the edge. Beautiful and you really sense the nature of ice and its ability to flow — but at the same time you realize that the flow takes centuries. We zoom low past a dozen ice cream fountains along the south edge of the island.

Ice Cream on James Ross Island

Ice Cream on James Ross Island

For many miles we cross sea ice – huge flat plates of broken ice only now cracking up in the Larsen A embayment. This year has been a very extensive ice year throughout Antarctica setting a record (nsidc.org/sea_ice_news). In the Peninsula and Weddell Sea (the ocean to the east of us), there is still heavy ice even though it is mid-February – usually the ice-free time of year for the northern Peninsula.

Sea Ice in Larsen A Embayment

Sea Ice in Larsen A Embayment

As we head toward Foyn, we fly past a much smaller Argentine base sometimes occupied in summer, although not this year. The base is Matienzo, designed to hold 8-12 people and support over-ice traverses and helicopters for exploring the glaciers of the Larsen area. Built in the 1960s, Matienzo is a bit weather-beaten since it is now rarely used; but we hope to make use of it more in the coming years.

Right next to Matienzo is a section of remnant ice shelf that is now the most northerly ice shelf in Antarcitca — the Seal Nunataks Ice Shelf — or at least, that is our working name for it. Technically it is a remnant of the Larsen Ice Shelf, stuck between the Larsen A and Larsen B embayments.

Matienzo Overflight

Matienzo Overflight

Seal Nunataks Ice Shelf

Seal Nunataks Ice Shelf

After about 90 minutes, we are there — Foyn Point, a large rock outcropping emerging from the ice cap, and the cape that marks the north side of Crane Glacier. We can see our two stations through the large porthole windows on the helo. After a few quick passes for a closer look, the pilot moves in and lands — so gently that touchdown was undetectable inside,  and we are off and working. The helo went back to Matienzo to wait, engine idling.

Foyn Point

Foyn Point

Helo on Foyn Point Unloading

Helo on Foyn Point Unloading

Helo Departs Foyn Point

Helo Departs Foyn Point

We got right to it, photographing the stations and assembling our gear for the surgery. The stations were in remarkably good shape, corrosion-free despite being next to an ocean. This may be a result of the near-continuous ice cover for the past few years — a string of cool summers since about 2008 have slowed the pace of ice evolution, and kept sea ice on the Larsen B embayment for the past four summers now. Unlike the Larsen A bay, the Larsen B shows no real signs of breaking out this year.

We first repaired the seismic sensor, attaching cables and re-booting – after all, we are the Cable Guys. The seismic sensor is intended to monitor large iceberg calving events on the nearby Hektoria and Crane Glaciers, and any continental seismicity that may be present. The sensor is located beneath a mound of rocks next to the power and communications box. A key step in the repair is the Jump Test — do we see a signal from the sensor reaching the box? ‘I got this!’ Rob says. And indeed, this is the job he was born to do. A thunderous leap and impact threatened to crack off the entire cliff we were standing on…. but when the dust had cleared, there it was: a clear spike in the data, practically spelling the word ‘Rob’ — or perhaps ‘Help!’.

The Instruments at Foyn Point

The Instruments at Foyn Point

Terry and Ted Look Inside the GPS

Terry and Ted Look Inside the GPS

The Jump Test

The Jump Test

We then repaired the GPS sensor, and called the groups managing the data reception on our Iridium phone. Success, and proven success, because the data was seen to be arriving back in the U.S.  We celebrated with a lunch extracted from our massive box of ‘snacks’ (just under 50 lbs).

On our return, we had a brief ground visit to Matienzo, to take some pictures and get a quick evaluation of how it would be useful to a larger group as a logistical base. It looks perfect, but in need of a little sprucing up.

Terry Matienzo

Terry Matienzo

We are now waiting on weather again for one possible opportunity to go to the second site – Cape Marsh, but we are prepared to depart at the next opportunity to go north. Looks like that may be February 26, a bit later than we’d hoped.

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