State of the Planet

News from the Columbia Climate School

Building the Team

The Ice pod team in Kangerlussuaq, Greenland including science, engineering and NYANG members.
The Icepod team in Kangerlussuaq, Greenland including science, engineering and New York Air National Guard members.

The Lamont IcePod team is a blended mix of engineers and scientists learning from each other through the design and testing of this new instrument. With a range of talents and backgrounds, the project mixes seasoned field workers with those new to field work; experienced instrument developers with those newly learning this end of engineering; and scientists with countless hours spent pouring over Greenland ice sheet data with those exploring the ice sheet for the first time. It is the opportunity for mentoring and development that comes from this mix of early career with experienced personnel that has made the IcePod Instrument Development Project a good fit for its American Recovery and Reinvestment Act funding.

Chris Bertinato trained as an aerospace engineer before coming to Icepod.
Engineer Chris Bertinato communicates with the flight crew while he monitors the Lidar at the equipment rack during calibration flights. Photo: R. Bell
The Lidar track of flight elevation collected during the GPS calibration.  The different colors represent changes in the surface elevation. The small black 'bites' in the track are where water blocks the return.
The Lidar track collected during the instrument calibration. The different colors represent changes in the reflectance which when matched to the GPS provide surface elevation. The small black “bites” in the track are where water blocks the return. The airstrip is the rectangular patch in the center.

So who makes up the IcePod engineering and science team?  As we work through data and examine the products collected in the first part of our field season there is an opportunity to introduce members of the team and the data and instruments they operate.

Chris Bertinato trained as an aerospace engineer before joining the IcePod team. In the air he is the team’s connection to the flight decisions made by the crew.  Like the members of the flight crew he dons a headset as soon as aircraft begins its warm up. The headsets are connected into the plane electronics through lengthy cabling that trails behind each set. The cabling necessitates a threading and weaving between the crew as they move about the aircraft, testing and checking equipment and switches. Watching them work one can imagine a class devoted to practicing safe maneuvering about the plane while tethered to the electronics system – something like a Maypole dance!

A graphic demonstrates  pitch, roll and yaw on an aircraft. (from Media Commons)
A graphic demonstrates pitch, roll and yaw on an aircraft. Image: Media Commons

Chris is a main operator of the equipment rack and has responsibility for the Laser Imaging Detection And Ranging (LIDAR) system part of the optical package in the pod taking constant  measurements to find the surface elevation, and the inertial navigation system (INS) used to locate or “georeference” the data. The INS is a critical navigation aid that employs several accelerometers (motion sensors) and gyroscopes (rotations sensors) to continuously calculate the position, orientation, direction and speed of the plane as it moves through space.  INS were first developed for rockets,  but have become essential instruments for collecting referenced data in an aircraft, since the pitch, roll and yaw of the plane (see drawing) as it moves through the air can make it difficult to correctly locate and orient the data for processing. For those of us used to flying on commercial airliners, movies and music can provide enough of a distraction that we don’t notice the regular rolling of the aircraft as it responds to buffeting by the air around it.

The INS sits atop the cylindrical laser set up.
The INS is the square box sitting atop the  laser set up. Photo: R. Bell

The cylindrical housing for the laser sits snugly in one of the pod bays with the INS sitting atop in the small grey box.  The laser focuses down through a clear panel, and scans back and forth in a swath that at 3000 ft. of altitude swings approximately 3000 ft. wide collecting elevation information. The data is then fed through a processor that turns it into elevation data.

Lidar image over the airstrip.
Lidar reflectance image collected over the airstrip. IcePod data

The image above shows a swath of laser data over the airbase, and can be used to help explain the instrument.  The color in the image shows the reflectance of different surfaces to the laser. You will see three of the LC130 aircraft lined up across the front of the airfield, cleaned from snow and clearly outlined in the data.  There are two additional aircraft positioned in the middle of the image that are still surrounded by snow and therefore remain somewhat obscured. Trees, roads and other features in the adjacent area are clearly imaged.

Lidar image of a Greenland meltwater channel shown etched through the landscape. (Icepod image)
Lidar image of a refrozen Greenland meltwater channel shown etched through the landscape. IcePod image

In Greenland Lidar will be used to assist with locating features of interest in the ice sheet. The image above of meltwater channels in Greenland will be important to track during the summer season as these channels can reactivate seasonally, becoming a blue stripe on the otherwise white landscape. These darkened blue sections will absorb more heat energy from the sun due to their altered reflectivity (albedo) encouraging additional surface melt.  In an upcoming post we will discuss how the infrared camera carried in the pod will allow us to track the heat energy in the channel both in its current state, and as it begins to melt later in the season.

Meltwater Channels on the surface of the Greenland Ice Sheet show how the color can darken absorbing heat energy. (Image P. Spector)
Meltwater Channels on the surface of the Greenland ice sheet show how the color can darken absorbing heat energy. Photo: P. Spector

Lidar will also be used to detect openings in the ice sheet (crevasses). Many of the crevasses are deep yet not wide, making them difficult to detect without the assistance of instruments. Detecting crevasses is important as they pose danger for pilots attempting to land and deliver support to ground crews, can be deadly for overland traverses that are carry scientists and support staff across the ice,  and can provide us with critical information on changes in the ice sheet. Lidar data collected in our IcePod flights can be used to help in all of these situations.

For more on the IcePod project: http://www.ldeo.columbia.edu/icepod

Science for the Planet: In these short video explainers, discover how scientists and scholars across the Columbia Climate School are working to understand the effects of climate change and help solve the crisis.
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