Antarctic workout
Thu 4th Jun 2009
Newcastle University, the largest geodesy group in the UK and a UNAVCO* associate member has just taken delivery of 10 NetRS Trimble Receivers from UK Trimble distributor, KOREC.
These receivers will be used in the Antarctic on a new monitoring project, a collaboration between Newcastle University, Durham University and British Antarctic Survey along with other overseas partners.
Newcastle's Matt King, a Reader in Polar Geodesy explains, "The project involves measuring the motion of the Earth's crust in Antarctica due to a process called glacial isostatic adjustment or postglacial rebound. Ice sitting on the Earth's crust depresses the crust in that location. When the ice mass is reduced, as it has done since the last glacial maximum, the crust rebounds. By using our NetRS receivers to measure this three dimensional rebound, we can get a good understanding of how much ice was there."
Newcastle University has the benefit of learning from UNAVCO's vast experience in polar GPS deployment as well as their own experiences to draw upon when it came to selecting the GPS for this project. Matt continues, "We were convinced that the Trimble NetRS's would deliver the robust permanent operation with low power consumption that we required. The NetRS provides easy setup, handles continuous data well and also allows us to directly log meteorological data in the receiver."
Trimble's NetRS features extremely rugged construction, low power consumption and dual power ports with intelligent switching. Its advanced communications control makes it easy to operate the receiver and manage data from a convenient location removing the need for a local computer. Following problems such as power loss, the NetRS receiver can reload its last known configuration settings eliminating the need to visit remote locations to manually reset the receiver.
The large internal memory of the receivers enables them to be deployed as permanent reference stations in the Antarctic where they will be monumented on the bedrock over a network spanning several hundred km. Recording parameters can be set up in advance on a computer and data will be downloaded once per year. When 2-3 years worth of data has been collected, it will then be analysed in scientific-level GPS processing software and ultimately used to produce maps of present-day ice mass change.
Matt concludes, "We've been impressed by the high level of support from KOREC and also from Trimble through UNAVCO, but ultimately on a project like this, the greatest challenges are deploying the instruments in cold environments, - especially given that we are trying to measure with a precision and accuracy of much less than 1mm/yr - and powering them. Indeed, the power systems we are deploying in the Antarctic cost more than the GPS!"
*UNAVCO is a non-profit membership-governed consortium, facilitates geoscience research and education using geodesy
ENDS
Image1: Trimble GPS antenna shrouded in a radome to protect against the build up of snow. Below is the yellow Trimble box containing the receiver and battery.
