Saturday, August 23, 2014

12. Flight to Marie Byrd Land

Excerpt from chapter 12

Luyendyk takes photos from ramp of Hercules in Marie Byrd Land
Luyendyk taking photos from ramp of Hercules in flight over
northern Ford Ranges, Marie Byrd Land, Antarctica. 
Photo © Steve Tucker

[Scene. Bruce and Team are on a reconnaissance flight – Recce – to the Fosdick Mountains in Marie Byrd Land. In a few days they will be dropped off here. On this flight barrels of fuel will be dropped by parachute ahead of time. They will take photographs to select camp locations and routes of safe travel.]

December 6, 1989
The next day we took off to the east. Three hours later our mountains came into sight. The pilot dropped the Hercules in altitude and decreased its speed. He lined up with the Chester snowfield and started the pass for the airdrop. Four 55-gallon drums of fuel sat strapped together on an aluminum palette – gas for our snowmobiles. The palette lay on rollers that ran along the length of the deck in the plane’s hold. Parachutes were rigged onto the barrels.

Three crewmen in harnesses approached the rear of the hold and hooked themselves to safety straps attached to the plane. One of them let down the tailgate ramp, parallel to the deck of the plane. This opened the rear - bright sky and mountains came into view. The sound level inside changed from the hum of the engines to the rush of the air passing by the open rear of the Herc at almost 200 miles an hour. I became alert, in awe.

The crew hooked the ripcord of the parachutes to the deck and pushed the bundle of barrels towards the rear almost to the edge of the tailgate ramp. They turned to look at a bank of signal lights inside the plane, red, yellow, green with the yellow one lit up. The green light came on and the crew slid the barrels out of the plane. In an instant I saw three parachutes burst open, then they disappeared.  Our team looked at each other with big grins and thumbs up; …how great was that?  

Just when I thought this was the coolest thing I’d seen in a long while, a crewman approached me and shouted into my earplugs, “Captain says you can go out on the tail ramp to take photos”. Wow! I unbuckled, got up and made my way towards the back. I looked at the wide-open rear of the plane and the blue-white empty air outside. It appeared like a gigantic TV screen in a dark room. A couple of crew stood by the opening silhouetted in the light. I felt hesitation - it came then went.

 They slipped me into a harness. I clipped into the safety line and sat down on the tailgate at the edge of the plane and the air that rushed by. Is this a good idea? The violence of the air that sped by and the peace of the blue sky and white snow, seemed dream-like. I was tempted to inch close to the edge and dangle my feet, get a photo of my boots in mid air. It frightened me that I had this thought. I knew I would be ripped out of the plane if I did that. So, with caution and exhilaration I prepared to shoot photos of the ground to develop and study later in McMurdo.

I looked over the edge and saw the shadow of our Herc slide over the snow, ice and rock only a couple of hundred feet below us. I began to snap away, at pace with my rapid heartbeat.

Fields of blue ice lay along the base of the ranges. How would we travel across these, be safe? I saw immense and deep snow pits, large enough to hold a two-story house, on the upwind sides of cliffs. Could we go down into these and get out? I saw fields of crevasses, not open, but covered in snow bridges. They lay in wait for us.

We will travel on the surface through the crevasse fields, not fly over them. They will be hard to see, hidden. How could we find them, not fall in not be killed? I was struck by this realization. My gut seized.

Saturday, August 2, 2014

Antarctic sea ice cover is increasing. Is Global Warming over?

sea ice Ross Sea. Photo © Bruce Luyendyk
Sea ice, Ross Sea, Antarctica, 1996. Photo © Bruce Luyendyk

Recent news items have drawn attention to Antarctic sea ice, the floating ice a meter or so thick that forms from freezing of the oceans surrounding Antarctica. Sea ice coverage is seasonal, more in the austral winter (June-September) and less in the summer (December-March), a difference of six-fold. A way to think of the scale is that the maximum extent of the sea ice about doubles the area of ice (land and sea) at the bottom of our planet. The story is that a glitch has been discovered in the estimate of the rate of change (change year over year) in the area of sea ice around Antarctica1,2.

Underlying the news of the glitch is the prior observation that the amount of sea ice has been increasing year over year. This is opposite the observation for the Arctic Ocean where famously, sea ice area has been shrinking year over year3.

First about the glitch; this is due to a difference in the methods used in computing Antarctic sea ice cover from satellite imagery. The method was changed in 1991.