Tag: glacier

A One-Day Tour of the Antarctic Cryosphere

 

From: Michael Studinger, Lamont-Doherty Earth Observatory, co-principal investigator on gravimeter team

 

PUNTA ARENAS, Chile – The weather forecast for our survey area yesterday, Nov. 16, over the Larsen C Ice Shelf predicted excellent conditions. Given the difficult weather situation over the past couple of days, this was a welcome change. After carefully studying satellite images and computer models and talking to the meteorologist at the Punta Arenas airport, we decided to fly NASA’s DC-8 over Antarctica again.

 

The flight took us through an almost complete tour of the Antarctic cryosphere. We followed the flow of ice from the interior all the way to the ocean where it ends up as icebergs and eventually melts. We began our tour by flying over small ice caps on the Antarctic Peninsula. The snow and ice that forms these ice caps eventually flows downhill through steep valleys that are occupied by glaciers or ice streams.

 

 

Glaciers flowing down steep valleys transport ice from the interior of Antarctica to the Larsen Ice Shelf near the coast.

 

 

At one point during the flight I took the seat in the cockpit behind our two pilots to get a better view of the spectacular scenery. We descended into a steep valley that was filled with ice flowing into the remnants of the former Larsen B Ice Shelf that broke apart a few years ago. The ice that’s flowing down through the valleys is pushing the ice in the ice shelves away and eventually huge chunks of ice break off and form icebergs. On the ice shelf the ice goes afloat and forms huge flat surfaces that seem to be endless. Beneath the ice is ocean water. We are here to study how the warm ocean water melts the ice shelf from beneath.

 

 

 

Small caps of stagnant ice cover the summits while the ice in the valley is moving relatively fast towards the coast.

 

 

Our next survey line takes us all the way to the edge of the ice shelf where we can see several of these gigantic icebergs floating in the far distance surrounded by sea ice and pockets of open water. After crisscrossing the part of the Larsen C Ice Shelf that is still intact, we head back up to the crest of the Antarctic Peninsula and repeat our mini-tour through the Antarctic cryosphere on a different survey line.

 

Every time I look out of the window and soak in the spectacular scenery I see an incredibly beautiful but fragile landscape.

 

We fly over the flat and mostly featureless Larsen Ice Shelf. You can see the steep mountains and glaciers in the background.

 

 

We complete our tour of the Antarctic cryosphere at the edge of the Larsen C Ice Shelf where we reach open water and sea ice.

 

 

All photos: Michael Studinger

 

A Splendid Day for Flying Glaciers

 

From: Kathryn Hansen, Science Writer, NASA Goddard Space Flight Center

 

A last-minute change in flight plans made for another great science flight on Nov. 4. Initial plans were to make a high-altitude flight, according to program director Jim Yungel of NASA’s Wallops Flight Facility.  But a forecaster in the Punta Arenas airport weather office advised crew of the potential for weather to interfere with the high-altitude measurements for the mission’s LVIS instrument.

 

With a new flight plan in place, NASA’s DC-8 took off just a few minutes after the scheduled 11 a.m. departure time. The new plan called for low-altitude flights over the Antarctic Peninsula.

 

“The forecaster was completely correct,” Yungel wrote to colleagues after the flight. “We flew into sunny conditions with occasional very light high cirrus over flight lines, resulting in an outstanding data set over the Larsen Ice Shelf and many impressive glaciers.”

 

Instruments that collect data at lower altitudes, including the Airborne Topographic Mapper, had a successful 11.3-hour flight.

 

“Much of this flight surveyed a grid over the Larsen C Ice Shelf,” Yungel wrote. “Later in the flight we surveyed several significant glaciers in the central Peninsula area, including the Atlee, Flask, Crane, Hektoria, and Drygalski glaciers. It was a splendid day for flying glaciers!”

 

Despite the busy flight, Yungel managed to capture these images of the landscape from the aircraft window …

 

 

 

A Challenging Glacier Flight

 

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.

 

YouTube Brings You to Chile

 

From: Steve Cole, Public Affairs Specialist, NASA Headquarters

 

PUNTA ARENAS, Chile — Did you know we are posting behind-the-scenes videos of Operation Ice Bridge on NASA Television’s YouTube channel? There are 4 “webisodes” online now in the Ice Bridge collection, with more to come.  It’s a great chance to see for yourself how science is done in the field (and in the air).

 

https://www.youtube.com/NASATelevision

 

 

The View Over Pine Island Glacier

 

From:  Steve Cole, Public Affairs Specialist, NASA Headquarters

PUNTA ARENAS, Chile — Here are some views from inside NASA’s DC-8 research aircraft during the mission’s Oct. 20 flight to Pine Island Glacier.

 

Monitors allowed everyone onboard to see where the DC-8 was during the nearly 11-hour roundtrip flight over Antarctica.  (NASA/Steve Cole)

 

Icebergs breaking off of the glacier in Pine Island Bay as the DC-8 completes one of its mapping runs over Pine Island Glacier.  (NASA/Steve Cole)

 

The DC-8 makes a turn over Pine Island Bay as it heads back up the glacier for another mapping run.  (NASA/Jane Peterson, NSERC)

 

Operation Ice Bridge project scientist Seelye Martin from the University of Washington during the flight.  (NASA/Jane Peterson, NSERC)