|Posted on Nov 03, 2009 03:30:57 PM | Ice Bridge | 7 Comments ||
From: Seelye Martin, Chief Scientist, Operation Ice Bridge
PUNTA ARENAS, Chile -- Using the first potentially clear day on the Antarctic Peninsula since we began flights in mid-October, we decided to fly on to targets there on Saturday, Oct. 31.
The DC-8 flight path took us over ice elevation lines surveyed by the ATM laser instrument in October 2008. The path included tracks over the Fleming Glacier, one to the George V ice shelf and a parallel one over Palmer Land, plus a single pass down Crane Glacier. The purpose of these flights will be to study the glacier response to the collapse of the adjacent ice shelves. There was also a long grounding line flown around the inside of the Larson-C Ice Shelf. This was a challenging flight, with large elevation changes.
This map of our actual flight lines (in red) shows that at the most southern point or our flight plan we turned early to get out of the clouds.
About three and a half hours into the flight we flew the survey line down the Fleming Glacier followed by a descent over the Clifford Glacier. We had a beautiful run down Clifford glacier, which was about our steepest descent in the mission. We then headed north over the southern edge of the Larsen-C shelf.
Eight hours into the flight we descended over Crane Glacier into Exasperation Inlet, which is next to Cape Disappointment. The DC-8 pilots say we have a little extra time, so we are going to do a run up Atlee Glacier.
One of the scientists onboard came by with the observation that the remnant of Larsen-B in Carr Inlet was showing signs of breaking loose. This does appear to be the one part of the continent where climate change is actually visible, particularly in the northern ice shelves and glaciers. The removal of the buttressing effect of the Larsen-B has led to a speedup of the surrounding glaciers. We repeated Atlee Glacier, then overflew Palmer Station. With that we climbed up in altitude and headed back to Punta Arenas.
Although we lost the southern end of our flight lines due to clouds, we got all of our northern track. We also took 300 kilometers of track along the grounding line of the Larsen C, covering most of the shelf.
This is my last flight report from Antarctica. I’m rotating out and William Krabill of NASA Wallops Flight Facility will continue as Ice Bridge project scientist for the remainder of our Antarctica 2009 mission.
A nunatak sticking through cloud deck at the southern end of our traverse.
The foot of Crane Glacier, with glacier ice mixed with sea ice to the left, and the glacier to the right. If you look at the rock wall, there is a suggestion of the former height of the glacier and adjacent Larsen B ice shelf. The glacier surface height drop of about 100 meters has been confirmed by repeated laser observations.
Mountains during maneuvering on the Peninsula plateau.
Tags : Antarctica, Martin, aircraft, glacier, ice shelf, science