Tag: science

Satellite Laser Fires Up for Campaign

 

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

 

On Wednesday, Sept. 30, engineers, scientists and mission operations personnel gathered around a single computer monitor tucked away in a corner of a building at NASA Goddard Space Flight Center in Greenbelt, Md. They were waiting for an indication that communication was established between the satellite ground station in Boulder, Colo., and NASA’s Ice, Cloud, and land Elevation Satellite (ICESat) in orbit. Once a connection was made, scientists can “command on” one of the satellite’s lasers and resume the collection of critical ice elevation data.

ICESat has been collecting elevation information of Arctic and Antarctic ice sheets and sea ice since 2003, but it’s uncertain how much longer the satellite’s last of three lasers will operate. So, scientists this fall are using ICESat to calibrate similar measurements from aircraft flights over targets in Antarctica during Operation Ice Bridge. The aircraft campaign will help bridge the data gap until ICESat-II is launched.

As the satellite made a first pass over Antarctica at about 4:15 p.m. EDT, a glitch in communications foiled the first contact. The satellite’s next pass over Antarctica gave ground station managers at University of Colorado’s Laboratory for Atmospheric and Space Physics in Boulder, Colo., enough time to fix the glitch.

At 5:50 p.m., station connection with the satellite was a success and “all commanding was executed as planned,” said David Hancock of Wallops Flight Facility in Wallops Island, Va., instrument manager for the satellite’s GLAS instrument that houses the lasers.

“We now have two ‘laser on’ campaigns per year,” said Shelley Thessen, of ICESat mission operations at Goddard. “It’s a common occurrence, but I still get a lump in my throat every time.”

Subsequent passes over Antarctica were also successful. Scientists have started analyzing the science data returned from the first pass, seen in the figure above as a blue line across central Antarctica.

“On this first pass, there was a small amount of thick cloud cover over the ice sheet,” said Jay Zwally, ICESat project scientist at Goddard. “Accurate measurements of the surface elevation were obtained from 93 percent of the 23,297 laser pulses over the ice sheet.”

 

Flying the Antarctic: The Trouble with Weather

 

From: Seelye Martin, Chief Scientist, Operation Ice Bridge

 

 

The issue of forecasting weather conditions over Antarctica presents a serious challenge to the Operation Ice Bridge DC-8 flights that get underway in just two weeks.

In the Southern Hemisphere, the Antarctic Ocean is unique in that the Antarctic Peninsula (the focus of many of our flights) is the only north-south oriented land barrier. Within this region, five or six weather systems accompanied by clouds and strong winds, rotate rapidly around the continent from west to east. The clouds from these systems extend from the ocean to the ice sheet, and are associated with strong winds. These systems are partially blocked by the mountains on the Peninsula that rise to approximately 10,000 feet (3,000 meters). Between these weather systems, periods of clear sky occur.

(See for yourself. Here is a link to one Antarctic forecast tool I’ve been using: http://www.mmm.ucar.edu/rt/wrf/amps.  After opening the first page, click on “animations” at the top left; in the next frame select “cloud base” under the first pull-down menu on the left. The image above is a sample of what you’ll see.)

The challenge in planning the flights is that we require clear weather over the target area to operate the lasers. For aircraft safety, we also need to avoid severe storms.

 

We will obtain our forecasts by working with the Chilean weather service, with polar scientists from the Centro de Estudios Cientificos (Center for Scientific Studies), by examination of satellite imagery downloaded at the airfield, and by use of web-based forecasts.

 

Another mission challenge is that as it proceeds, our ability to obtain a cloud-free flight decreases. This occurs because at the beginning of the flight series, we have a variety of geographically dispersed targets, such as the sea ice in the Weddell and Amundsen seas, the Peninsula glaciers, and the ice sheet in the vicinity of Pine Island and Thwaites glaciers. This gives us geographic flexibility and the ability to choose a cloud-free region from many different sites. As the flights proceed, the number of our target sites decrease, and finding cloud-free conditions over the target will become more difficult.

 

Communicating 'Wondrous' Research Efforts

 

From: Jill Hummels, Public Information Officer, University of Kansas School of Engineering

In August, my boss sent me an email with the subject line of “FYI.” I know what he really meant to type was “Great Opportunity.” In the email he asked if I would be willing to travel to the southern tip of Chile to report on the activities of a University of Kansas research team.

My response: “I carry my passport with me at all times … Yes.”

As a public information officer for the KU School of Engineering, I work with people who do truly wondrous things that few others outside the school or the field know much about. My job is to ensure more people know the wondrous, seemingly magical, research efforts of our faculty.

This time I’m following the adventures of KU researchers who’ve developed radars and computer models that can tell the world a lot about what’s happening to our polar ice. Not a bad gig. The KU team, housed at the Center for Remote Sensing of Ice Sheets and led by Professor Chris Allen, was selected by NASA to provide much of the instrumentation for Operation Ice Bridge. Also, not a bad gig.

I’ve traveled to most states and visited many Canadian provinces and a few Mexican states, but this is my first trip outside North America. I’m pretty excited about the opportunity to travel to Punta Arenas, so much so that a 29-hour flight itinerary seems like a pretty cool endurance test. I guess it’s good that I like to fly. That finely honed skill will come in handy if I’m able to sit in on a flight over Antarctica in NASA’s DC-8.

My family is pretty pumped about my Chile excursion, too, although we haven’t broken the news to the dog, yet. We think she might be jealous.

 

Thinking on Your Feet on the Ice

 

From: Nick Frearson, Gravimeter Instrument Team, Lamont-Doherty Earth Observatory

 

Hi there! I’m senior engineer at Columbia University’s Lamont Doherty Earth Observatory in New York, and my role in Operation Ice Bridge is to work with the gravimeter. This instrument can see beneath ice sheets into the water and bedrock below to reveal the hidden shape of this part of the ice sheet – critical information for predicting how ice sheets will change as the climate warms.

 

I see the importance of the poles as an indicator of change. There you can see how sensitive the environment is and how easy it is to upset its delicate balance. Changes to the ice sheets at the poles will change sea levels and climate around the world.

 

I have traveled to both poles and like the wildlife, solitude and shear expansiveness of these amazing places that remind me constantly of how fragile life is. I enjoy thinking on my feet and solving problems with limited resources — so different from our normal civilized lives.

 

On my last trip to Antarctica, we mapped a huge and remote ice-covered mountain range in the middle of the continent, trying to understand how and when the ice sheets formed. Inside my tent I could hear the constant whispering of the wind over the snow, mixed with the music of Radiohead, Coldplay, Snow Patrol, Imogen Heap, among many others.

 

I miss my friends when I’m away. Two summers ago, I went to Canada’s Ellesmere Island with my good colleague, Michael Studinger, to test gravity instruments near the North Pole. The island is stunning with windswept hillsides leading down to frozen fjords. I walked for miles across the island, observing Musk Ox and wolves go about their lives. Back at camp, I enjoyed listening to other scientists talk about their travels.

 

I hope that you enjoy reading about our exploits flying over Antarctica as much as I’ll enjoy taking part in them.

 

 

Nick Frearson from the Lamont-Doherty Earth Observatory

“at home in his snow hole near Mount Erebus,

Antarctica, Christmas 2008.”

 

A New Way to Experience Antarctica


 

From: Michael Studinger, Instrument Co-Principal Investigator, Lamont-Doherty Earth Observatory 

 

The scale and style of Operation Ice Bridge will be a new experience for me. I’ve been involved in airborne research for more than a decade using ice-penetrating radar systems, airborne laser scanning, gravity and magnetics to learn more about the polar ice caps and how they behave.

 

In previous airborne campaigns we have used small instrumented Twin Otter aircraft and operated out of remote field camps deep in the interior of Antarctica and at high elevations and extreme temperatures. This means living and working in tents for months at temperatures around -20 to -40°F and flying in unpressurized aircraft at high altitude. There are no showers and only limited communications with the outside world in these remote field camps.

 

The Ice Bridge campaign will be very different from that. We’ll be flying non-stop roundtrips on the large NASA DC-8 from Punta Arenas, Chile. It feels a bit strange to be flying over Antarctica without actually setting foot on the continent and experiencing firsthand the icy cold and breathtaking beauty of the polar landscape. During Ice Bridge we will have to enjoy the fascination of the polar environment from a heated and pressurized aircraft cabin.

 

I am a research scientist at Columbia University’s Lamont-Doherty Earth Observatory in New York. My background is airborne geophysics which I use to study the ice caps and the Earth’s crust in polar regions. For Ice Bridge, I’ll be involved in measuring the Earth’s gravity field to estimate how deep the water is beneath floating glaciers along the Antarctic Peninsula.

 

I’m looking forward to a relaxed airborne campaign, where you leave from Punta Arenas in the morning and return to civilization in the evening.

 

The Road to Antarctic Science

 

Welcome to the Operation Ice Bridge blog.

 

This new NASA mission is the largest airborne survey of polar ice ever flown.  It is also the most sophisticated, using the latest scientific instruments to give an unprecedented three-dimensional view of the ice sheets, floating ice shelves, and sea ice of both the Arctic and Antarctic.

 

In this blog you’ll hear from a wide range of people involved in Ice Bridge as the mission begins its new expedition: flying over western Antarctica in NASA’s DC-8 starting in October. The base of operations is Punta Arenas, Chile, at the very southern end of South America.

 

– Steve Cole, NASA Office of Public Affairs, Washington, D.C.

 

 

From: Seelye Martin, Chief Scientist, Operation Ice Bridge

 

 

Seelye Martin, University of Washington, in Thule, Greenland this May. Mt. Dundas is in the background. Credit: Sinead Farell

 

I first got involved in polar studies in 1970, when I was hired as an assistant professor at the University of Washington in Seattle. At the university, I did a variety of cold room experiments on sea ice, then took part in a large number of sea ice studies in the Beaufort and Chukchi Seas using land-based helicopters.

 

Later, working from the NOAA ship Surveyor and Coast Guard icebreaker Westwind, I participated in several cruises studying the sea ice of the Bering Sea, serving as chief scientist on two of these cruises. I also worked in the field and laboratory on the mechanics of how spilled oil interacts with sea ice, and made use of satellite data to study the large-scale sea ice behavior. This research led to my coming to work at NASA Headquarters in Washington, D.C., in 2006 as Cryospheric Program Manager and then to my current role as chief scientist of the Ice Bridge campaign.

 

One reason that I took the position at NASA and am continuing with the Ice Bridge work is my concern over the diminishing Arctic sea ice cover and the recent accelerating losses from the Greenland and Antarctic ice sheets. The excitement for me in helping to plan and run this campaign is to participate in the design of experiments to replace the observations made by the aging NASA ICESat satellite, and to focus airborne observations on the rapidly changing regions of the Greenland and Antarctic ice sheets.

 

For the Antarctic flights, we have a comprehensive suite of instruments: lasers for the ice surface elevation, ice-penetrating radar for the bedrock topography, snow radar for snow thickness on sea ice, a gravimeter to measure the shape of seawater-filled cavity beneath the ice tongues, a digital mapping camera to measure three-dimensional relief, and a variety of precision navigation tools to determine where we are and to allow us to follow the ICESat tracks.

 

This instrument suite should lead to a unique set of ice sheet and sea ice observations. And by comparing the measured ice elevations with previous ICESat tracks, we’ll be able to determine the rates at which the critical glaciers are losing volume.

 

Four Times Around the World in 40 Days

 

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

 

SANTIAGO, Chile — For the first time in more than 40 days, the nose of the NASA DC-8 pointed north on Nov. 23 after taking off from Punta Arenas airport. We have completed our Antarctic survey flights and are heading back home to Palmdale, Calif. Before we start climbing to cruising altitude we fly at 300 feet above the Strait of Magellan just outside Punta Arenas to collect atmospheric chemistry data. After two passes over the strait, we head north towards Santiago and enjoy the spectacular view of the Patagonian Ice Fields and the Torres del Paine from 35,000 feet.

 

 

 

The Patagonian ice fields seen from 35,000 feet during the DC-8 flight from Punta Arenas to Santiago, Chile on Nov. 23. Photo by Michael Studinger.

 

 

Over the past five weeks, the Ice Bridge teams have collected a landmark data set over Antarctica. We had originally planned to fly 17 missions but actually accomplished 21. We have flown more than 155,000 kilometers or almost 100,000 miles. This is almost four times around the world in 40 days.

 

During this time, we collected high-precision measurements of the ice surface elevation of many glaciers and ice shelves in Antarctica. We have also mapped the thickness of the glacier ice and snow cover, have measured the freeboards and snow thicknesses of the sea ice in the Weddell and Ross seas, and have collected gravity measurements that will allow us to estimate how deep the water is beneath the floating glacier tongues.

 

We have collected an enormous amount of data and are keen to analyze the data together with our colleagues when we are back in our labs. From the analysis of this data we will gain a much more detailed understanding of how the glaciers, ice sheets, and sea ice respond to changes in the climate system.

 

A project of this size is only possible with the support of many people. We could not have done this without the help and support of our Chilean friends and colleagues in Punta Arenas and Valdivia, the airport and hotel staff, and the many NASA and university people back home who have worked long hours to make this project happen. We thank the National Science Foundation for giving us access to their forecasts. And we appreciate the help and assistance of the forecaster at the British Rothera Base (thanks Tony). For planning our flights, we also acknowledge our use of and dependence on the UCAR/NCAR NSF-supported Antarctic Mesoscale Prediction System. We had terrific aircraft crews both in the air and on the ground as well as excellent science teams.

 

We all had a great time in Punta Arenas and are looking forward to come back next year for another Ice Bridge campaign over Antarctica.

 

 

Map shows all the flight lines flown during the Operation Ice Bridge 2009 Antarctic campaign. Created by Michael Studinger.

 

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.

 

On Headset: Communication is Key

 

From: Jill Hummels, Public Information Officer, University of Kansas School of Engineering

 

PUNTA ARENAS, Chile, Oct. 21 — Every flight in NASA’s Operation Ice Bridge mission begins and ends with a briefing. Today’s pilot Dick Ewers calls the disparate group to order and starts the morning with a roll call of the flight manifest. Every person on the flight must be accounted for with either a self-announced “Here!” or another passenger providing an accounting of their whereabouts as “on the plane.” Today’s total: 31.

 

The project scientist Seelye Martin then gives an overview of the day’s science objective, which instruments will be onboard that day, and which will play the lead role.

 

The flight crew provides a brief review of issues that need monitoring by all passengers and crew. At the top of the list: making sure lavatory faucets aren’t left running and ensuring everyone knows that “equipment and hot food have priority in the aisles.” The navigator announces some of the parameters for the day’s flight, such as altitude and duration.  Other crew members reiterate safety awareness and the day’s schedule. “On the plane by 9. Doors close at 9:30. In the air by 10.”

 

Before taking off, all people on board must be on communication headsets. “Mission” (the flight crew) performs an audible check of all research instrument teams on board, and a representative from each team provides a status update.

 

Once airborne, researchers can choose to take off the headsets, but they are the best tool for communicating changing needs, problems, wishes, hopes and dreams with flight crew and the mission’s project science. Discussions, though not constant, are frequent.

 

About an hour into the flight, Mission announces impending pitch and roll maneuvers needed to calibrate some of the instruments.

 

Throughout the flight, everyone is free to move about the cabin, mingle, take pictures and talk shop.

  

Several instrument stations are outfitted with touch-screen monitors that provide real-time data, including satellite weather images, “webcams” of what’s directly in front of the plane and below it (below), and a Google Earth application that maps the current location of the DC-8.

 

 

Near the end of today’s roundtrip flight, the headsets are back on and everyone is back in their seats. Mission calls out each research team for a quick review of the day’s highlights, and any special landing procedures needed for data acquisition or instrument calibration.

 

On the ground, researchers quickly gather their personal belongings and any necessary portable equipment and haul it to the cramped mission offices at the airport. Within a half hour of the plane’s doors swinging open, all flight crew and researchers gather for a post-flight briefing on the day’s mission.

 

The day ends with a quick review of the next flight mission and schedule: “Briefing at 7. Power on at 7:30. Doors open by 8. Doors close by 8:30. In the air by 9.”

 

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