Icepod Plus Potential Field: An Integrated Approach For Understanding Ice Shelf Processes

Abstract:

Warm water flowing beneath the large floating ice shelves in Antarctica will play an important role in how fast sea level rises. The lack of detailed bathymetry beneath the large ice shelves and lack of understanding of their internal structure inherently limits our knowledge of how ice shelves will thin and collapse. Understanding the bathymetry beneath the remaining ice shelves is critical to understanding how ice shelves will thin in the future and how that will impact the flux of ice into the global ocean. The Ross Ice Shelf, the largest ice shelf remaining on our planet, buttresses the West Antarctic Ice Sheet. The bathymetry beneath the Ross Ice Shelf is the least explored piece of ocean floor on our planet.

The IcePod is a compact integrated ice imaging system developed for use on any C-130 aircraft developed with NSF support. The initial development program was targeted towards investigating glacial and ice-sheet processes. In this program, deep and shallow ice radars were developed. Optical instruments, including a scanning laser, Infra-red camera and visible wave camera were integrated into the pod. We have expanded the IcePod instrument suite to include the potential field measurements of magnetic and gravity anomalies with support from the Moore Foundation. During the development, a total field cesium sensor magnetometer and 3-axis fluxgate from previously funded work were also incorporated into the pod. Their behavioral response to being located close to high-frequency electronics, power supplies and metallic objects were studied. We describe in part some of that development process and the positive findings that resulted. The Icepod group is also actively pursuing the development, modification and incorporation of a new gravimeter into the suite of instruments available to the program and is investigating reduction in size of this that may eventually lead to incorporating the gravimeter into the pod itself. As part of this program we are also recording and analyzing data in parallel to this from on-board IMUs that has the capacity of leading to the development of a ‘strap down’ gravimeter. This IcePod plus Potential Fields instrumentation suite will be deployed in Antarctica in 2015 and 2016 to study the Ross Ice Shelf, producing new high resolution imaging of the bathymetry and the ice shelf structure.