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Success

November 22, 2010

Ted writes:

Clear weather finally prevailed on the morning of November 18, and after one last check of satellite imagery, we bolted at noon in our 1970s-vintage DeHavilland Twin Otter (with brand-new instruments and engines) off the runway at Rothera, headed for the Larsen Ice Shelf. Aboard were myself, Martin, and Jenn, BAS pilot Doug Cochran, and a BAS staffer named Andy “Boat” Wilson – known as Boat because he is a diver and a boatman for the base, and a sturdy guy to have along.

A few puffs of grey cloud passed by on our way upward, but then gave way to one of the most glorious spectacles in glaciology: the Larsen Ice Shelves and the eastern coast of the Antarctic Peninsula. Spilling ice from the ridge, which sits in the southern storm track building snow, flows down like marshmallow cream through black, jagged peaks, and then spreads out to an impossibly flat, broad sheet of ice. Only the subtlest of rolls and ridges mark the history of the bending that the ice endured to reach the sea.

What we saw confirmed what we’ve learned from the data streaming in from the AMIGOS and other stations. While the west side of the Peninsula has experienced unusual snowfall, the east side, where our stations are, has been bone-dry and very warm all winter. Already there are melt ponds slowly filling, and the dry warm wind has scrubbed the surface down, exposing every crack and ridge.

Our first rendezvous was at the Scar Inlet AMIGOS site. Although the station is still functioning, two of the most important measuring devices have gone silent or intermittent over the winter: weather and ice motion. The camera is still working well for now. But as we circled the site, we realized that the landing last year was something of a miracle: the site is surrounded by dozens of narrow (2-foot wide)
cracks and slots. The pilot circled several times, determined to give us a landing if there was any chance; but the risk of bending a ski on the airplane was too great. We did manage to get several pictures of the site, and in some ways the news is good. The station is still standing, and with the anchors still firmly in place.

We then flew up the first major glacier feeding the Scar Inlet Shelf, Flask Glacier. A second AMIGOS there is working very well, but needed new software and a new snow reflectivity sensor. We use the snow reflectivity to gauge when melting occurs: the snow darkens quite a bit when it is wet. The landing went perfectly; right on the tracks from last year, and Doug pulled the plane right up to the station. The wind was brisk, but warm, right about at freezing. The station has about 70 centimeters of snow around it, but it is an oddity–everywhere around it is evidence of windswept snow surface.

While we were standing there, the camera came to life! It moved to the six set shots that Terry had programmed in months ago. I tried to remember the sequence, and started leaping around in the snow, trying to get in every picture. But the camera was too fast. So, in every one of those pictures, one second later, I’m standing right there smiling. Martin, Mr. Smarty-pants, let the camera come to him, by standing still, and Jenn just shrugged and kept working. Jenn and I opened the station and changed the software chip, while Martin removed the old snow sensor and installed the new one. A quick call to Terry confirmed it was all working again. We took off.

Martin’s main goal was to repair the GPS station on Leppard, and that was our next stop. Here again, the dryness and warmth of the winter and spring amazed us. There were crevasses and even melt ponds all over the glacier. We found the station, and as we had guessed, the solar panels had blown over during the winter. We had expected a major digging effort, but in fact the panels were just below the surface. It required about two hours to excavate them, stand them up again, and re-secure them. On the sat-phone again, the UNAVCO office confirmed we had a working station. Next!

It was getting late, now, the sun definitely lower as we rounded a cape on the ocean and approached the rusty-looking outcrop at Cape Framnes. Here Doug really had a challenge. None of us had seen this site before, and it was steep, icy, and loaded with narrow cracks. The outcrop was perfect for helicopters, deadly for an aircraft. We made three different low approaches, each one ending with some new Scottish swearing (Doug is from Glasgow), and a proper decision not to touch down. We eventually found a site 2.5 miles and 400 meters above our outcrop. Martin, Andy, and I hopped out, grabbed ice axes and the new satellite modem, and started hiking.

It was beautiful now, light winds, cool and refreshing, and we were walking downhill towards a stunning seascape. Walking and walking. The last 400 yards before the rock was a windswept blue ice surface, slick enough so that footing was tricky, but then we made it onto the rock.

The outcrop had a blasted appearance, shattered fragments covering a primeval surface of lakes, sand, gravel, boulders nestled between blue ocean, turquoise sunset sky, and pale blue ice. Truly: an end of the earth, and a spectacular place to be. The fix went quickly, and we paused to take in the surroundings before the hike back to the waiting plane.

***

I want to take this opportunity to thank the people at Rothera and British Antarctic Survey. At every step they have been generous, helpful, responsible, and eager to see us get our work done. I especially want to thank Doug Cochran, who did an outstanding job of piloting, and made the right decision on every single landing and attempt (IMHO). He pushed for our success, but never lost sight of the far more important safety decision. Andy “Boat” was a ready, cheerful helper for whatever we had to do (and he practically dragged my lifeless body up the hill after Cape Framnes, after a very tiring, hugely successful day.) And, when we finally flew into to the Rothera hangar, at 20 minutes to midnight, both Clem Collins (a veritable institution at Rothera) and Andy Barker were there to help get the plane in and unload our gear. Thanks.

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