21 November, 2016 by Staff Reporter
The ROSETTA-Ice research program has returned to Antarctica for a second field season of aerial- and ocean-based surveys of the Ross Ice Shelf, and this year they’ll be conducting surveys at a higher density than the previous season in 2015.
Scientists have observed that polar ice sheets and glaciers are changing much more quickly than anticipated, and have been looking for new ways to collect the data they need to understand these changes, and the processes driving them.
The Ross Ice Shelf, a massive apron of ice approximately the same size as France, is particularly crucial to understanding the impacts of increased sea temperatures on the global climate system.
The ROSETTA-Ice research program is designed to provide high value data on how the fragile ice shelf is reacting to increasing ocean temperatures, and the reasons such changes are occurring.
ROSETTA-Ice is shorthand for “Uncovering the Ross Ocean and ice Shelf Environment and Tectonic setting Through Aerogeophysical surveys and modelling of the Ross ICE Shelf”, and the name draws parallels between the project and the race to solve the secrets of the enigmatic Rosetta Stone.
The ROSETTA research program aims to conduct a detailed survey of the Ross Ice Shelf, primarily through flying back and forth over the ice shelf in a LC-130 aircraft to create a grid of the information collected. The LC-130 is equipped with an “IcePod”, which contains various scientific instruments to collect aerial measurements and create a detailed map of both the ice shelf and the sea bed below it.
The IcePod collects a range of information, including ice surface elevation (using LiDAR), ice thickness (using radar), and the shape and materials of the ocean floor beneath the ice shelf (using gravity and magnetic measurements).
As well as aerial surveying, the ROSETTA researchers also use six “Alamo drifters”, floating units deployed into the ocean in order to collect data on ocean circulation along the front of the ice shelf. Matching this circulation data with the grid map created by aerial surveying will help to improve scientific models of how increasing sea temperatures can lead to additional melting of the ice shelf.
Season one in 2015 flights were planned at 20 km grid spacing to put together the framework for the 2016 season.
The density of the survey grid has been doubled for the 2016 program, and will be flown at a 10 km spacing, providing a much more complete picture of the ice shelf itself.
The IcePods used by the aircraft in the ROSETTA program employ a type of remote sensing technique called LiDar (Light Detection and Ranging), which uses light to develop an image of the surface of the Earth. LiDAR uses a series of light pulses to illuminate the area below, and the reflected light is measured to create three dimensional images of the land surface with a high degree of accuracy.