Posts Tagged ‘Palmer’

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Palmer to Palmer

February 24, 2010

Ted writes:

The LARISSA Glaciology Team made its way back to the RV Nathaniel B. Palmer, in two unusual leaps.

After getting picked up from Scar Inlet, we landed in Rothera Station, in the southern end of the Peninsula. We knew that if we wanted to get anything further done, we needed to get back aboard the ship. We had installed everything we had brought on Flask Glacier and Scar Inlet. We still needed to fix the SCAR inlet Web cam, and install a seismic listening station for glacier calving, and the ridge-top high-resolution AMIGOS camera. And time was running out: it was now February 17, and the Palmer would head north no later than the 26th.

The team saw these crabeater seals during a boat ride near Rothera Station.

As usual, the staff at Rothera were amazingly generous, taking us on an evening boat tour of some nearby islands while we waited for good weather for the next step. The boat ride was spectacular. Every shoal and beach teemed with wildlife.

The next day was February 18, my birthday. Not a birthday present in sight, but I thought if we could get back to the ship, well, I’d take it as a sign from The Big Guy that I was doing okay by him (or her). That morning, the Twin Otter pilot gave us some cause for hope. His plan was to fly us to Palmer Station, the U.S. base, and have us wait there for a helo pick-up from the ship. The only trick was the runway at Palmer, set on a small ice cap behind the base. The ice has been badly eroded by the warming climate in recent years. It has rarely been used since 1990, and in fact the only landing in years was a medical evacuation in 2009. I was thinking how ironic it would be if I were the first casualty of Antarctic global warming.

We flew between the bases (song: “The Blue Danube“) over the icebound landscape. Though every glance out the window was a masterpiece of landscape art, we at this point were able to read or nap as the dramatic sculpted architecture of the continent rolled beneath us.

And then we saw the “runway.” It was the most rutted, cracked-up, slush-pit of a glacier I’d ever seen. It was sloped, with the end of it as steep as a ski run, leading straight to a boulder field. The line of runway marker flags looked like some kind of practical joke. Even more humorous, the flags were numbered, in descending order, like a countdown in some movie thriller, “Four-hundred meters to self-destruct.”

A crowd from the station had gathered, taking bets no doubt on whether or not we would survive. But they picked the wrong pilot to mess with. Richie circled once, and then slapped the plane down on the uppermost third of the bobsled run—I mean runway—and then threw the prop into reverse (Amazing fact: on a taxi-way, Twin Otters can actually back up under their own power). We bounced to a stop, not quite crossing the “6” on the doom countdown.

The Palmer people (total population 38) were really welcoming. But I was shocked when Ronald pointed out a “Happy Birthday” banner in the galley. As it happened, February 18 was also the birthday for the Palmer Station chef, Staci, and the back-up chef, Diane, had gone all out for a celebration dinner and cake. All I had to do was shout “and Ted!” at the right moment in the birthday song. We had a fun night at the Palmer bar and hot tub.

The team caught a ride from Palmer Station back to the the N.B. Palmer aboard the research vessel Lawrence M. Gould.

At Palmer Station, we noticed a large orange ship parked in front of the base. This was the RV Lawrence M. Gould, the other major U.S. polar research vessel, used mostly for oceanography around the continent. We learned that the ship was basically on stand-by for an entire month with little to do. We hatched a plan.

We pulled away from the pier on the afternoon of February 20th, with a thousand pounds of gear strapped to the deck of our new water-taxi, the Gould. Officially, the Gould was out to replenish its water tanks (it desalinates the sea-water) and pick up some devices for sediment studies from the Palmer. But for the five us, it was one fine ride.

This was my third birthday in Antarctica. So I guess I’m 3 in Antarctica years. Looking at the photo on our way out of Palmer, Martin informed me that Antarctica years seem to be a bit more taxing than even dog years. But as the two ships met up, at sunset in a coastal fjord, it seemed as if things were proceeding nicely for this toddler.

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Radar survey of Röhss Glacier

January 14, 2010

Martin Truffer, of the University of Alaska, tows a radar sled across Rohss Glacier.

Ted writes:

On January 11, two of the glaciology team aboard the N.B.Palmer, Erin Pettit and Martin Truffer of University of Alaska, flew to nearby Röhss Glacier to conduct a radar survey and test the science equipment. Although not part of the original LARISSA mission, the Röhss Glacier is similar to the glaciers of the Larsen B embayment in that it is rapidly retreating and thinning in the aftermath of ice shelf disintegration, in this case, the disintegration of the Prince Gustav Ice Shelf in January 1995. The Röhss has retreated nearly 25 kilometers (16 miles) in that time.

The survey tested the deep radar system that we plan to use on the Larsen B glaciers, which measures ice thickness. We also measured the glacier flow rate at the site using precision GPS systems. Early results show that the glacier is roughly just 200 meters (700 feet) thick at this point, and flowing at about 200 meters (700 feet) per year.

Erin writes:

Ted has been studying this glacier’s retreat through satellite imagery, so he was pretty happy to have Martin and I get some ground data to supplement his satellite work. It was, of course, a glorious flight over with Chris. We stopped on a bedrock knob next to the glacier to set up a quick GPS base station. It’s all volcanic rock over there, with lots of crumbly pumice.

Ted had given us approximate coordinates based on his satellite images for landing on the glacier. The entire lower part of the glacier is broken up with crevasses due to its fast retreat, so the point Ted gave us was in the middle of a crevasse field. But as it was the most interesting part of the glacier for the data we wanted, we chose a broad, flat icy area between two large rifts. The flat area was probably 200 or 300 meters (700 to 1000 feet) long and 30 meters (100 feet) wide. It was snow-free, with dirty ice showing through, so we new it was safe to land and work.

We put a GPS on the glacier to measure its motion. Martin’s processing of those data this morning show that it’s moving about 60 centimeters (24 inches) per day. We also strung out our radar system (two 20-meter antennas, which spread out quite a ways on our little ice ledge). We profiled as much terrain with the radar system as we could safely between crevasses,  about 200 meters. We had fun navigating around snow patches, which can hide crevasses. We also jumped over a few tiny crevasses in the ice, where we could see what was solid and what was not.

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